diff --git a/llvm/docs/CommandGuide/llvm-objcopy.rst b/llvm/docs/CommandGuide/llvm-objcopy.rst index 8dc1357635e1b..b90a5a4ddb0b5 100644 --- a/llvm/docs/CommandGuide/llvm-objcopy.rst +++ b/llvm/docs/CommandGuide/llvm-objcopy.rst @@ -178,6 +178,10 @@ multiple file formats. specified ```` values. Can be specified multiple times to update multiple sections. +.. option:: --verbose + + List all object files modified. + Supported flag names are `alloc`, `load`, `noload`, `readonly`, `exclude`, `debug`, `code`, `data`, `rom`, `share`, `contents`, `merge`, `strings`, and `large`. Not all flags are meaningful for all object file formats or target diff --git a/llvm/include/llvm/ObjCopy/CommonConfig.h b/llvm/include/llvm/ObjCopy/CommonConfig.h index aea9cd6f9a9c7..83ad4590d9c72 100644 --- a/llvm/include/llvm/ObjCopy/CommonConfig.h +++ b/llvm/include/llvm/ObjCopy/CommonConfig.h @@ -274,6 +274,7 @@ struct CommonConfig { bool StripNonAlloc = false; bool StripSections = false; bool StripUnneeded = false; + bool Verbose = false; bool Weaken = false; bool DecompressDebugSections = false; diff --git a/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp b/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp index 5aa0079f3fbc7..6cf42ea0e0303 100644 --- a/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp +++ b/llvm/lib/ObjCopy/ELF/ELFObjcopy.cpp @@ -546,7 +546,7 @@ static Error replaceAndRemoveSections(const CommonConfig &Config, }; } - if (Error E = Obj.removeSections(ELFConfig.AllowBrokenLinks, RemovePred)) + if (Error E = Obj.removeSections(ELFConfig.AllowBrokenLinks, RemovePred, Config.Verbose)) return E; if (Error E = Obj.compressOrDecompressSections(Config)) @@ -782,6 +782,7 @@ static Error verifyNoteSection(StringRef Name, endianness Endianness, // system. The only priority is that keeps/copies overrule removes. static Error handleArgs(const CommonConfig &Config, const ELFConfig &ELFConfig, ElfType OutputElfType, Object &Obj) { + Obj.VerboseOutput = Config.Verbose; if (Config.OutputArch) { Obj.Machine = Config.OutputArch->EMachine; Obj.OSABI = Config.OutputArch->OSABI; @@ -790,7 +791,7 @@ static Error handleArgs(const CommonConfig &Config, const ELFConfig &ELFConfig, if (!Config.SplitDWO.empty() && Config.ExtractDWO) { return Obj.removeSections( ELFConfig.AllowBrokenLinks, - [&Obj](const SectionBase &Sec) { return onlyKeepDWOPred(Obj, Sec); }); + [&Obj](const SectionBase &Sec) { return onlyKeepDWOPred(Obj, Sec); }, Config.Verbose); } // Dump sections before add/remove for compatibility with GNU objcopy. diff --git a/llvm/lib/ObjCopy/ELF/ELFObject.cpp b/llvm/lib/ObjCopy/ELF/ELFObject.cpp index 45c7ea49b5d93..8976612d5e67e 100644 --- a/llvm/lib/ObjCopy/ELF/ELFObject.cpp +++ b/llvm/lib/ObjCopy/ELF/ELFObject.cpp @@ -766,14 +766,20 @@ Error SymbolTableSection::removeSymbols( function_ref ToRemove) { Symbols.erase( std::remove_if(std::begin(Symbols) + 1, std::end(Symbols), - [ToRemove](const SymPtr &Sym) { return ToRemove(*Sym); }), - std::end(Symbols)); + [&](const SymPtr &Sym) { + if (ToRemove(*Sym)) { + if(VerboseOutput) + outs() << "Symbols Removed:" << Sym->Name<< "\n"; + return true; + } + return false; + })); + auto PrevSize = Size; Size = Symbols.size() * EntrySize; if (Size < PrevSize) IndicesChanged = true; assignIndices(); - return Error::success(); } void SymbolTableSection::replaceSectionReferences( @@ -2195,7 +2201,7 @@ Error Object::updateSectionData(SectionBase &S, ArrayRef Data) { } Error Object::removeSections( - bool AllowBrokenLinks, std::function ToRemove) { + bool AllowBrokenLinks, std::function ToRemove, bool VerboseOutput) { auto Iter = std::stable_partition( std::begin(Sections), std::end(Sections), [=](const SecPtr &Sec) { @@ -2230,6 +2236,9 @@ Error Object::removeSections( for (auto &RemoveSec : make_range(Iter, std::end(Sections))) { for (auto &Segment : Segments) Segment->removeSection(RemoveSec.get()); + if (VerboseOutput) { + outs() << "removed section: " << (RemoveSec.get()->Name); + } RemoveSec->onRemove(); RemoveSections.insert(RemoveSec.get()); } @@ -2273,17 +2282,20 @@ Error Object::replaceSections( if (Error E = removeSections( /*AllowBrokenLinks=*/false, - [=](const SectionBase &Sec) { return FromTo.count(&Sec) > 0; })) + [=](const SectionBase &Sec) { return FromTo.count(&Sec) > 0; }, false)) return E; llvm::sort(Sections, SectionIndexLess); return Error::success(); } Error Object::removeSymbols(function_ref ToRemove) { - if (SymbolTable) - for (const SecPtr &Sec : Sections) + if (SymbolTable){ + for (const SecPtr &Sec : Sections){ if (Error E = Sec->removeSymbols(ToRemove)) return E; + outs() << "removed symbols:" << Sec->Name; + } + } return Error::success(); } @@ -2570,7 +2582,7 @@ static Error removeUnneededSections(Object &Obj) { : Obj.SymbolTable->getStrTab(); return Obj.removeSections(false, [&](const SectionBase &Sec) { return &Sec == Obj.SymbolTable || &Sec == StrTab; - }); + }, false); } template Error ELFWriter::finalize() { @@ -2624,7 +2636,7 @@ template Error ELFWriter::finalize() { if (Error E = Obj.removeSections(false /*AllowBrokenLinks*/, [this](const SectionBase &Sec) { return &Sec == Obj.SectionIndexTable; - })) + }, false)) return E; } } diff --git a/llvm/lib/ObjCopy/ELF/ELFObject.h b/llvm/lib/ObjCopy/ELF/ELFObject.h index d8f79a4b1a3cc..bcda100343813 100644 --- a/llvm/lib/ObjCopy/ELF/ELFObject.h +++ b/llvm/lib/ObjCopy/ELF/ELFObject.h @@ -814,6 +814,8 @@ class SymbolTableSection : public SectionBase { void setStrTab(StringTableSection *StrTab) { SymbolNames = StrTab; } void assignIndices(); +private: + bool VerboseOutput; protected: std::vector> Symbols; StringTableSection *SymbolNames = nullptr; @@ -856,6 +858,7 @@ class SymbolTableSection : public SectionBase { static bool classof(const SectionBase *S) { return S->OriginalType == ELF::SHT_SYMTAB; } + bool getVerboseOutput() { return VerboseOutput; } }; struct Relocation { @@ -1195,6 +1198,7 @@ class Object { uint32_t Flags; bool HadShdrs = true; + bool VerboseOutput; bool MustBeRelocatable = false; StringTableSection *SectionNames = nullptr; SymbolTableSection *SymbolTable = nullptr; @@ -1224,7 +1228,7 @@ class Object { ConstRange segments() const { return make_pointee_range(Segments); } Error removeSections(bool AllowBrokenLinks, - std::function ToRemove); + std::function ToRemove, bool VerboseOutput); Error compressOrDecompressSections(const CommonConfig &Config); Error replaceSections(const DenseMap &FromTo); Error removeSymbols(function_ref ToRemove); diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp deleted file mode 100644 index ca8a20b4b7312..0000000000000 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ /dev/null @@ -1,4997 +0,0 @@ -//===- InstCombineAndOrXor.cpp --------------------------------------------===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// -// -// This file implements the visitAnd, visitOr, and visitXor functions. -// -//===----------------------------------------------------------------------===// - -#include "InstCombineInternal.h" -#include "llvm/Analysis/CmpInstAnalysis.h" -#include "llvm/Analysis/InstructionSimplify.h" -#include "llvm/IR/ConstantRange.h" -#include "llvm/IR/Intrinsics.h" -#include "llvm/IR/PatternMatch.h" -#include "llvm/Transforms/InstCombine/InstCombiner.h" -#include "llvm/Transforms/Utils/Local.h" - -using namespace llvm; -using namespace PatternMatch; - -#define DEBUG_TYPE "instcombine" - -/// This is the complement of getICmpCode, which turns an opcode and two -/// operands into either a constant true or false, or a brand new ICmp -/// instruction. The sign is passed in to determine which kind of predicate to -/// use in the new icmp instruction. -static Value *getNewICmpValue(unsigned Code, bool Sign, Value *LHS, Value *RHS, - InstCombiner::BuilderTy &Builder) { - ICmpInst::Predicate NewPred; - if (Constant *TorF = getPredForICmpCode(Code, Sign, LHS->getType(), NewPred)) - return TorF; - return Builder.CreateICmp(NewPred, LHS, RHS); -} - -/// This is the complement of getFCmpCode, which turns an opcode and two -/// operands into either a FCmp instruction, or a true/false constant. -static Value *getFCmpValue(unsigned Code, Value *LHS, Value *RHS, - InstCombiner::BuilderTy &Builder, FMFSource FMF) { - FCmpInst::Predicate NewPred; - if (Constant *TorF = getPredForFCmpCode(Code, LHS->getType(), NewPred)) - return TorF; - return Builder.CreateFCmpFMF(NewPred, LHS, RHS, FMF); -} - -/// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise -/// (V < Lo || V >= Hi). This method expects that Lo < Hi. IsSigned indicates -/// whether to treat V, Lo, and Hi as signed or not. -Value *InstCombinerImpl::insertRangeTest(Value *V, const APInt &Lo, - const APInt &Hi, bool isSigned, - bool Inside) { - assert((isSigned ? Lo.slt(Hi) : Lo.ult(Hi)) && - "Lo is not < Hi in range emission code!"); - - Type *Ty = V->getType(); - - // V >= Min && V < Hi --> V < Hi - // V < Min || V >= Hi --> V >= Hi - ICmpInst::Predicate Pred = Inside ? ICmpInst::ICMP_ULT : ICmpInst::ICMP_UGE; - if (isSigned ? Lo.isMinSignedValue() : Lo.isMinValue()) { - Pred = isSigned ? ICmpInst::getSignedPredicate(Pred) : Pred; - return Builder.CreateICmp(Pred, V, ConstantInt::get(Ty, Hi)); - } - - // V >= Lo && V < Hi --> V - Lo u< Hi - Lo - // V < Lo || V >= Hi --> V - Lo u>= Hi - Lo - Value *VMinusLo = - Builder.CreateSub(V, ConstantInt::get(Ty, Lo), V->getName() + ".off"); - Constant *HiMinusLo = ConstantInt::get(Ty, Hi - Lo); - return Builder.CreateICmp(Pred, VMinusLo, HiMinusLo); -} - -/// Classify (icmp eq (A & B), C) and (icmp ne (A & B), C) as matching patterns -/// that can be simplified. -/// One of A and B is considered the mask. The other is the value. This is -/// described as the "AMask" or "BMask" part of the enum. If the enum contains -/// only "Mask", then both A and B can be considered masks. If A is the mask, -/// then it was proven that (A & C) == C. This is trivial if C == A or C == 0. -/// If both A and C are constants, this proof is also easy. -/// For the following explanations, we assume that A is the mask. -/// -/// "AllOnes" declares that the comparison is true only if (A & B) == A or all -/// bits of A are set in B. -/// Example: (icmp eq (A & 3), 3) -> AMask_AllOnes -/// -/// "AllZeros" declares that the comparison is true only if (A & B) == 0 or all -/// bits of A are cleared in B. -/// Example: (icmp eq (A & 3), 0) -> Mask_AllZeroes -/// -/// "Mixed" declares that (A & B) == C and C might or might not contain any -/// number of one bits and zero bits. -/// Example: (icmp eq (A & 3), 1) -> AMask_Mixed -/// -/// "Not" means that in above descriptions "==" should be replaced by "!=". -/// Example: (icmp ne (A & 3), 3) -> AMask_NotAllOnes -/// -/// If the mask A contains a single bit, then the following is equivalent: -/// (icmp eq (A & B), A) equals (icmp ne (A & B), 0) -/// (icmp ne (A & B), A) equals (icmp eq (A & B), 0) -enum MaskedICmpType { - AMask_AllOnes = 1, - AMask_NotAllOnes = 2, - BMask_AllOnes = 4, - BMask_NotAllOnes = 8, - Mask_AllZeros = 16, - Mask_NotAllZeros = 32, - AMask_Mixed = 64, - AMask_NotMixed = 128, - BMask_Mixed = 256, - BMask_NotMixed = 512 -}; - -/// Return the set of patterns (from MaskedICmpType) that (icmp SCC (A & B), C) -/// satisfies. -static unsigned getMaskedICmpType(Value *A, Value *B, Value *C, - ICmpInst::Predicate Pred) { - const APInt *ConstA = nullptr, *ConstB = nullptr, *ConstC = nullptr; - match(A, m_APInt(ConstA)); - match(B, m_APInt(ConstB)); - match(C, m_APInt(ConstC)); - bool IsEq = (Pred == ICmpInst::ICMP_EQ); - bool IsAPow2 = ConstA && ConstA->isPowerOf2(); - bool IsBPow2 = ConstB && ConstB->isPowerOf2(); - unsigned MaskVal = 0; - if (ConstC && ConstC->isZero()) { - // if C is zero, then both A and B qualify as mask - MaskVal |= (IsEq ? (Mask_AllZeros | AMask_Mixed | BMask_Mixed) - : (Mask_NotAllZeros | AMask_NotMixed | BMask_NotMixed)); - if (IsAPow2) - MaskVal |= (IsEq ? (AMask_NotAllOnes | AMask_NotMixed) - : (AMask_AllOnes | AMask_Mixed)); - if (IsBPow2) - MaskVal |= (IsEq ? (BMask_NotAllOnes | BMask_NotMixed) - : (BMask_AllOnes | BMask_Mixed)); - return MaskVal; - } - - if (A == C) { - MaskVal |= (IsEq ? (AMask_AllOnes | AMask_Mixed) - : (AMask_NotAllOnes | AMask_NotMixed)); - if (IsAPow2) - MaskVal |= (IsEq ? (Mask_NotAllZeros | AMask_NotMixed) - : (Mask_AllZeros | AMask_Mixed)); - } else if (ConstA && ConstC && ConstC->isSubsetOf(*ConstA)) { - MaskVal |= (IsEq ? AMask_Mixed : AMask_NotMixed); - } - - if (B == C) { - MaskVal |= (IsEq ? (BMask_AllOnes | BMask_Mixed) - : (BMask_NotAllOnes | BMask_NotMixed)); - if (IsBPow2) - MaskVal |= (IsEq ? (Mask_NotAllZeros | BMask_NotMixed) - : (Mask_AllZeros | BMask_Mixed)); - } else if (ConstB && ConstC && ConstC->isSubsetOf(*ConstB)) { - MaskVal |= (IsEq ? BMask_Mixed : BMask_NotMixed); - } - - return MaskVal; -} - -/// Convert an analysis of a masked ICmp into its equivalent if all boolean -/// operations had the opposite sense. Since each "NotXXX" flag (recording !=) -/// is adjacent to the corresponding normal flag (recording ==), this just -/// involves swapping those bits over. -static unsigned conjugateICmpMask(unsigned Mask) { - unsigned NewMask; - NewMask = (Mask & (AMask_AllOnes | BMask_AllOnes | Mask_AllZeros | - AMask_Mixed | BMask_Mixed)) - << 1; - - NewMask |= (Mask & (AMask_NotAllOnes | BMask_NotAllOnes | Mask_NotAllZeros | - AMask_NotMixed | BMask_NotMixed)) - >> 1; - - return NewMask; -} - -// Adapts the external decomposeBitTestICmp for local use. -static bool decomposeBitTestICmp(Value *Cond, CmpInst::Predicate &Pred, - Value *&X, Value *&Y, Value *&Z) { - auto Res = llvm::decomposeBitTest(Cond, /*LookThroughTrunc=*/true, - /*AllowNonZeroC=*/true); - if (!Res) - return false; - - Pred = Res->Pred; - X = Res->X; - Y = ConstantInt::get(X->getType(), Res->Mask); - Z = ConstantInt::get(X->getType(), Res->C); - return true; -} - -/// Handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E). -/// Return the pattern classes (from MaskedICmpType) for the left hand side and -/// the right hand side as a pair. -/// LHS and RHS are the left hand side and the right hand side ICmps and PredL -/// and PredR are their predicates, respectively. -static std::optional> -getMaskedTypeForICmpPair(Value *&A, Value *&B, Value *&C, Value *&D, Value *&E, - Value *LHS, Value *RHS, ICmpInst::Predicate &PredL, - ICmpInst::Predicate &PredR) { - - // Here comes the tricky part: - // LHS might be of the form L11 & L12 == X, X == L21 & L22, - // and L11 & L12 == L21 & L22. The same goes for RHS. - // Now we must find those components L** and R**, that are equal, so - // that we can extract the parameters A, B, C, D, and E for the canonical - // above. - - // Check whether the icmp can be decomposed into a bit test. - Value *L1, *L11, *L12, *L2, *L21, *L22; - if (decomposeBitTestICmp(LHS, PredL, L11, L12, L2)) { - L21 = L22 = L1 = nullptr; - } else { - auto *LHSCMP = dyn_cast(LHS); - if (!LHSCMP) - return std::nullopt; - - // Don't allow pointers. Splat vectors are fine. - if (!LHSCMP->getOperand(0)->getType()->isIntOrIntVectorTy()) - return std::nullopt; - - PredL = LHSCMP->getPredicate(); - L1 = LHSCMP->getOperand(0); - L2 = LHSCMP->getOperand(1); - // Look for ANDs in the LHS icmp. - if (!match(L1, m_And(m_Value(L11), m_Value(L12)))) { - // Any icmp can be viewed as being trivially masked; if it allows us to - // remove one, it's worth it. - L11 = L1; - L12 = Constant::getAllOnesValue(L1->getType()); - } - - if (!match(L2, m_And(m_Value(L21), m_Value(L22)))) { - L21 = L2; - L22 = Constant::getAllOnesValue(L2->getType()); - } - } - - // Bail if LHS was a icmp that can't be decomposed into an equality. - if (!ICmpInst::isEquality(PredL)) - return std::nullopt; - - Value *R11, *R12, *R2; - if (decomposeBitTestICmp(RHS, PredR, R11, R12, R2)) { - if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) { - A = R11; - D = R12; - } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) { - A = R12; - D = R11; - } else { - return std::nullopt; - } - E = R2; - } else { - auto *RHSCMP = dyn_cast(RHS); - if (!RHSCMP) - return std::nullopt; - // Don't allow pointers. Splat vectors are fine. - if (!RHSCMP->getOperand(0)->getType()->isIntOrIntVectorTy()) - return std::nullopt; - - PredR = RHSCMP->getPredicate(); - - Value *R1 = RHSCMP->getOperand(0); - R2 = RHSCMP->getOperand(1); - bool Ok = false; - if (!match(R1, m_And(m_Value(R11), m_Value(R12)))) { - // As before, model no mask as a trivial mask if it'll let us do an - // optimization. - R11 = R1; - R12 = Constant::getAllOnesValue(R1->getType()); - } - - if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) { - A = R11; - D = R12; - E = R2; - Ok = true; - } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) { - A = R12; - D = R11; - E = R2; - Ok = true; - } - - // Avoid matching against the -1 value we created for unmasked operand. - if (Ok && match(A, m_AllOnes())) - Ok = false; - - // Look for ANDs on the right side of the RHS icmp. - if (!Ok) { - if (!match(R2, m_And(m_Value(R11), m_Value(R12)))) { - R11 = R2; - R12 = Constant::getAllOnesValue(R2->getType()); - } - - if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) { - A = R11; - D = R12; - E = R1; - } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) { - A = R12; - D = R11; - E = R1; - } else { - return std::nullopt; - } - } - } - - // Bail if RHS was a icmp that can't be decomposed into an equality. - if (!ICmpInst::isEquality(PredR)) - return std::nullopt; - - if (L11 == A) { - B = L12; - C = L2; - } else if (L12 == A) { - B = L11; - C = L2; - } else if (L21 == A) { - B = L22; - C = L1; - } else if (L22 == A) { - B = L21; - C = L1; - } - - unsigned LeftType = getMaskedICmpType(A, B, C, PredL); - unsigned RightType = getMaskedICmpType(A, D, E, PredR); - return std::optional>( - std::make_pair(LeftType, RightType)); -} - -/// Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) into a single -/// (icmp(A & X) ==/!= Y), where the left-hand side is of type Mask_NotAllZeros -/// and the right hand side is of type BMask_Mixed. For example, -/// (icmp (A & 12) != 0) & (icmp (A & 15) == 8) -> (icmp (A & 15) == 8). -/// Also used for logical and/or, must be poison safe. -static Value *foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed( - Value *LHS, Value *RHS, bool IsAnd, Value *A, Value *B, Value *D, Value *E, - ICmpInst::Predicate PredL, ICmpInst::Predicate PredR, - InstCombiner::BuilderTy &Builder) { - // We are given the canonical form: - // (icmp ne (A & B), 0) & (icmp eq (A & D), E). - // where D & E == E. - // - // If IsAnd is false, we get it in negated form: - // (icmp eq (A & B), 0) | (icmp ne (A & D), E) -> - // !((icmp ne (A & B), 0) & (icmp eq (A & D), E)). - // - // We currently handle the case of B, C, D, E are constant. - // - const APInt *BCst, *DCst, *OrigECst; - if (!match(B, m_APInt(BCst)) || !match(D, m_APInt(DCst)) || - !match(E, m_APInt(OrigECst))) - return nullptr; - - ICmpInst::Predicate NewCC = IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE; - - // Update E to the canonical form when D is a power of two and RHS is - // canonicalized as, - // (icmp ne (A & D), 0) -> (icmp eq (A & D), D) or - // (icmp ne (A & D), D) -> (icmp eq (A & D), 0). - APInt ECst = *OrigECst; - if (PredR != NewCC) - ECst ^= *DCst; - - // If B or D is zero, skip because if LHS or RHS can be trivially folded by - // other folding rules and this pattern won't apply any more. - if (*BCst == 0 || *DCst == 0) - return nullptr; - - // If B and D don't intersect, ie. (B & D) == 0, try to fold isNaN idiom: - // (icmp ne (A & FractionBits), 0) & (icmp eq (A & ExpBits), ExpBits) - // -> isNaN(A) - // Otherwise, we cannot deduce anything from it. - if (!BCst->intersects(*DCst)) { - Value *Src; - if (*DCst == ECst && match(A, m_ElementWiseBitCast(m_Value(Src))) && - !Builder.GetInsertBlock()->getParent()->hasFnAttribute( - Attribute::StrictFP)) { - Type *Ty = Src->getType()->getScalarType(); - if (!Ty->isIEEELikeFPTy()) - return nullptr; - - APInt ExpBits = APFloat::getInf(Ty->getFltSemantics()).bitcastToAPInt(); - if (ECst != ExpBits) - return nullptr; - APInt FractionBits = ~ExpBits; - FractionBits.clearSignBit(); - if (*BCst != FractionBits) - return nullptr; - - return Builder.CreateFCmp(IsAnd ? FCmpInst::FCMP_UNO : FCmpInst::FCMP_ORD, - Src, ConstantFP::getZero(Src->getType())); - } - return nullptr; - } - - // If the following two conditions are met: - // - // 1. mask B covers only a single bit that's not covered by mask D, that is, - // (B & (B ^ D)) is a power of 2 (in other words, B minus the intersection of - // B and D has only one bit set) and, - // - // 2. RHS (and E) indicates that the rest of B's bits are zero (in other - // words, the intersection of B and D is zero), that is, ((B & D) & E) == 0 - // - // then that single bit in B must be one and thus the whole expression can be - // folded to - // (A & (B | D)) == (B & (B ^ D)) | E. - // - // For example, - // (icmp ne (A & 12), 0) & (icmp eq (A & 7), 1) -> (icmp eq (A & 15), 9) - // (icmp ne (A & 15), 0) & (icmp eq (A & 7), 0) -> (icmp eq (A & 15), 8) - if ((((*BCst & *DCst) & ECst) == 0) && - (*BCst & (*BCst ^ *DCst)).isPowerOf2()) { - APInt BorD = *BCst | *DCst; - APInt BandBxorDorE = (*BCst & (*BCst ^ *DCst)) | ECst; - Value *NewMask = ConstantInt::get(A->getType(), BorD); - Value *NewMaskedValue = ConstantInt::get(A->getType(), BandBxorDorE); - Value *NewAnd = Builder.CreateAnd(A, NewMask); - return Builder.CreateICmp(NewCC, NewAnd, NewMaskedValue); - } - - auto IsSubSetOrEqual = [](const APInt *C1, const APInt *C2) { - return (*C1 & *C2) == *C1; - }; - auto IsSuperSetOrEqual = [](const APInt *C1, const APInt *C2) { - return (*C1 & *C2) == *C2; - }; - - // In the following, we consider only the cases where B is a superset of D, B - // is a subset of D, or B == D because otherwise there's at least one bit - // covered by B but not D, in which case we can't deduce much from it, so - // no folding (aside from the single must-be-one bit case right above.) - // For example, - // (icmp ne (A & 14), 0) & (icmp eq (A & 3), 1) -> no folding. - if (!IsSubSetOrEqual(BCst, DCst) && !IsSuperSetOrEqual(BCst, DCst)) - return nullptr; - - // At this point, either B is a superset of D, B is a subset of D or B == D. - - // If E is zero, if B is a subset of (or equal to) D, LHS and RHS contradict - // and the whole expression becomes false (or true if negated), otherwise, no - // folding. - // For example, - // (icmp ne (A & 3), 0) & (icmp eq (A & 7), 0) -> false. - // (icmp ne (A & 15), 0) & (icmp eq (A & 3), 0) -> no folding. - if (ECst.isZero()) { - if (IsSubSetOrEqual(BCst, DCst)) - return ConstantInt::get(LHS->getType(), !IsAnd); - return nullptr; - } - - // At this point, B, D, E aren't zero and (B & D) == B, (B & D) == D or B == - // D. If B is a superset of (or equal to) D, since E is not zero, LHS is - // subsumed by RHS (RHS implies LHS.) So the whole expression becomes - // RHS. For example, - // (icmp ne (A & 255), 0) & (icmp eq (A & 15), 8) -> (icmp eq (A & 15), 8). - // (icmp ne (A & 15), 0) & (icmp eq (A & 15), 8) -> (icmp eq (A & 15), 8). - if (IsSuperSetOrEqual(BCst, DCst)) { - // We can't guarantee that samesign hold after this fold. - if (auto *ICmp = dyn_cast(RHS)) - ICmp->setSameSign(false); - return RHS; - } - // Otherwise, B is a subset of D. If B and E have a common bit set, - // ie. (B & E) != 0, then LHS is subsumed by RHS. For example. - // (icmp ne (A & 12), 0) & (icmp eq (A & 15), 8) -> (icmp eq (A & 15), 8). - assert(IsSubSetOrEqual(BCst, DCst) && "Precondition due to above code"); - if ((*BCst & ECst) != 0) { - // We can't guarantee that samesign hold after this fold. - if (auto *ICmp = dyn_cast(RHS)) - ICmp->setSameSign(false); - return RHS; - } - // Otherwise, LHS and RHS contradict and the whole expression becomes false - // (or true if negated.) For example, - // (icmp ne (A & 7), 0) & (icmp eq (A & 15), 8) -> false. - // (icmp ne (A & 6), 0) & (icmp eq (A & 15), 8) -> false. - return ConstantInt::get(LHS->getType(), !IsAnd); -} - -/// Try to fold (icmp(A & B) ==/!= 0) &/| (icmp(A & D) ==/!= E) into a single -/// (icmp(A & X) ==/!= Y), where the left-hand side and the right hand side -/// aren't of the common mask pattern type. -/// Also used for logical and/or, must be poison safe. -static Value *foldLogOpOfMaskedICmpsAsymmetric( - Value *LHS, Value *RHS, bool IsAnd, Value *A, Value *B, Value *C, Value *D, - Value *E, ICmpInst::Predicate PredL, ICmpInst::Predicate PredR, - unsigned LHSMask, unsigned RHSMask, InstCombiner::BuilderTy &Builder) { - assert(ICmpInst::isEquality(PredL) && ICmpInst::isEquality(PredR) && - "Expected equality predicates for masked type of icmps."); - // Handle Mask_NotAllZeros-BMask_Mixed cases. - // (icmp ne/eq (A & B), C) &/| (icmp eq/ne (A & D), E), or - // (icmp eq/ne (A & B), C) &/| (icmp ne/eq (A & D), E) - // which gets swapped to - // (icmp ne/eq (A & D), E) &/| (icmp eq/ne (A & B), C). - if (!IsAnd) { - LHSMask = conjugateICmpMask(LHSMask); - RHSMask = conjugateICmpMask(RHSMask); - } - if ((LHSMask & Mask_NotAllZeros) && (RHSMask & BMask_Mixed)) { - if (Value *V = foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed( - LHS, RHS, IsAnd, A, B, D, E, PredL, PredR, Builder)) { - return V; - } - } else if ((LHSMask & BMask_Mixed) && (RHSMask & Mask_NotAllZeros)) { - if (Value *V = foldLogOpOfMaskedICmps_NotAllZeros_BMask_Mixed( - RHS, LHS, IsAnd, A, D, B, C, PredR, PredL, Builder)) { - return V; - } - } - return nullptr; -} - -/// Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E) -/// into a single (icmp(A & X) ==/!= Y). -static Value *foldLogOpOfMaskedICmps(Value *LHS, Value *RHS, bool IsAnd, - bool IsLogical, - InstCombiner::BuilderTy &Builder, - const SimplifyQuery &Q) { - Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr; - ICmpInst::Predicate PredL, PredR; - std::optional> MaskPair = - getMaskedTypeForICmpPair(A, B, C, D, E, LHS, RHS, PredL, PredR); - if (!MaskPair) - return nullptr; - assert(ICmpInst::isEquality(PredL) && ICmpInst::isEquality(PredR) && - "Expected equality predicates for masked type of icmps."); - unsigned LHSMask = MaskPair->first; - unsigned RHSMask = MaskPair->second; - unsigned Mask = LHSMask & RHSMask; - if (Mask == 0) { - // Even if the two sides don't share a common pattern, check if folding can - // still happen. - if (Value *V = foldLogOpOfMaskedICmpsAsymmetric( - LHS, RHS, IsAnd, A, B, C, D, E, PredL, PredR, LHSMask, RHSMask, - Builder)) - return V; - return nullptr; - } - - // In full generality: - // (icmp (A & B) Op C) | (icmp (A & D) Op E) - // == ![ (icmp (A & B) !Op C) & (icmp (A & D) !Op E) ] - // - // If the latter can be converted into (icmp (A & X) Op Y) then the former is - // equivalent to (icmp (A & X) !Op Y). - // - // Therefore, we can pretend for the rest of this function that we're dealing - // with the conjunction, provided we flip the sense of any comparisons (both - // input and output). - - // In most cases we're going to produce an EQ for the "&&" case. - ICmpInst::Predicate NewCC = IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE; - if (!IsAnd) { - // Convert the masking analysis into its equivalent with negated - // comparisons. - Mask = conjugateICmpMask(Mask); - } - - if (Mask & Mask_AllZeros) { - // (icmp eq (A & B), 0) & (icmp eq (A & D), 0) - // -> (icmp eq (A & (B|D)), 0) - if (IsLogical && !isGuaranteedNotToBeUndefOrPoison(D)) - return nullptr; // TODO: Use freeze? - Value *NewOr = Builder.CreateOr(B, D); - Value *NewAnd = Builder.CreateAnd(A, NewOr); - // We can't use C as zero because we might actually handle - // (icmp ne (A & B), B) & (icmp ne (A & D), D) - // with B and D, having a single bit set. - Value *Zero = Constant::getNullValue(A->getType()); - return Builder.CreateICmp(NewCC, NewAnd, Zero); - } - if (Mask & BMask_AllOnes) { - // (icmp eq (A & B), B) & (icmp eq (A & D), D) - // -> (icmp eq (A & (B|D)), (B|D)) - if (IsLogical && !isGuaranteedNotToBeUndefOrPoison(D)) - return nullptr; // TODO: Use freeze? - Value *NewOr = Builder.CreateOr(B, D); - Value *NewAnd = Builder.CreateAnd(A, NewOr); - return Builder.CreateICmp(NewCC, NewAnd, NewOr); - } - if (Mask & AMask_AllOnes) { - // (icmp eq (A & B), A) & (icmp eq (A & D), A) - // -> (icmp eq (A & (B&D)), A) - if (IsLogical && !isGuaranteedNotToBeUndefOrPoison(D)) - return nullptr; // TODO: Use freeze? - Value *NewAnd1 = Builder.CreateAnd(B, D); - Value *NewAnd2 = Builder.CreateAnd(A, NewAnd1); - return Builder.CreateICmp(NewCC, NewAnd2, A); - } - - const APInt *ConstB, *ConstD; - if (match(B, m_APInt(ConstB)) && match(D, m_APInt(ConstD))) { - if (Mask & (Mask_NotAllZeros | BMask_NotAllOnes)) { - // (icmp ne (A & B), 0) & (icmp ne (A & D), 0) and - // (icmp ne (A & B), B) & (icmp ne (A & D), D) - // -> (icmp ne (A & B), 0) or (icmp ne (A & D), 0) - // Only valid if one of the masks is a superset of the other (check "B&D" - // is the same as either B or D). - APInt NewMask = *ConstB & *ConstD; - if (NewMask == *ConstB) - return LHS; - if (NewMask == *ConstD) - return RHS; - } - - if (Mask & AMask_NotAllOnes) { - // (icmp ne (A & B), B) & (icmp ne (A & D), D) - // -> (icmp ne (A & B), A) or (icmp ne (A & D), A) - // Only valid if one of the masks is a superset of the other (check "B|D" - // is the same as either B or D). - APInt NewMask = *ConstB | *ConstD; - if (NewMask == *ConstB) - return LHS; - if (NewMask == *ConstD) - return RHS; - } - - if (Mask & (BMask_Mixed | BMask_NotMixed)) { - // Mixed: - // (icmp eq (A & B), C) & (icmp eq (A & D), E) - // We already know that B & C == C && D & E == E. - // If we can prove that (B & D) & (C ^ E) == 0, that is, the bits of - // C and E, which are shared by both the mask B and the mask D, don't - // contradict, then we can transform to - // -> (icmp eq (A & (B|D)), (C|E)) - // Currently, we only handle the case of B, C, D, and E being constant. - // We can't simply use C and E because we might actually handle - // (icmp ne (A & B), B) & (icmp eq (A & D), D) - // with B and D, having a single bit set. - - // NotMixed: - // (icmp ne (A & B), C) & (icmp ne (A & D), E) - // -> (icmp ne (A & (B & D)), (C & E)) - // Check the intersection (B & D) for inequality. - // Assume that (B & D) == B || (B & D) == D, i.e B/D is a subset of D/B - // and (B & D) & (C ^ E) == 0, bits of C and E, which are shared by both - // the B and the D, don't contradict. Note that we can assume (~B & C) == - // 0 && (~D & E) == 0, previous operation should delete these icmps if it - // hadn't been met. - - const APInt *OldConstC, *OldConstE; - if (!match(C, m_APInt(OldConstC)) || !match(E, m_APInt(OldConstE))) - return nullptr; - - auto FoldBMixed = [&](ICmpInst::Predicate CC, bool IsNot) -> Value * { - CC = IsNot ? CmpInst::getInversePredicate(CC) : CC; - const APInt ConstC = PredL != CC ? *ConstB ^ *OldConstC : *OldConstC; - const APInt ConstE = PredR != CC ? *ConstD ^ *OldConstE : *OldConstE; - - if (((*ConstB & *ConstD) & (ConstC ^ ConstE)).getBoolValue()) - return IsNot ? nullptr : ConstantInt::get(LHS->getType(), !IsAnd); - - if (IsNot && !ConstB->isSubsetOf(*ConstD) && - !ConstD->isSubsetOf(*ConstB)) - return nullptr; - - APInt BD, CE; - if (IsNot) { - BD = *ConstB & *ConstD; - CE = ConstC & ConstE; - } else { - BD = *ConstB | *ConstD; - CE = ConstC | ConstE; - } - Value *NewAnd = Builder.CreateAnd(A, BD); - Value *CEVal = ConstantInt::get(A->getType(), CE); - return Builder.CreateICmp(CC, CEVal, NewAnd); - }; - - if (Mask & BMask_Mixed) - return FoldBMixed(NewCC, false); - if (Mask & BMask_NotMixed) // can be else also - return FoldBMixed(NewCC, true); - } - } - - // (icmp eq (A & B), 0) | (icmp eq (A & D), 0) - // -> (icmp ne (A & (B|D)), (B|D)) - // (icmp ne (A & B), 0) & (icmp ne (A & D), 0) - // -> (icmp eq (A & (B|D)), (B|D)) - // iff B and D is known to be a power of two - if (Mask & Mask_NotAllZeros && - isKnownToBeAPowerOfTwo(B, /*OrZero=*/false, /*Depth=*/0, Q) && - isKnownToBeAPowerOfTwo(D, /*OrZero=*/false, /*Depth=*/0, Q)) { - // If this is a logical and/or, then we must prevent propagation of a - // poison value from the RHS by inserting freeze. - if (IsLogical) - D = Builder.CreateFreeze(D); - Value *Mask = Builder.CreateOr(B, D); - Value *Masked = Builder.CreateAnd(A, Mask); - return Builder.CreateICmp(NewCC, Masked, Mask); - } - return nullptr; -} - -/// Try to fold a signed range checked with lower bound 0 to an unsigned icmp. -/// Example: (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n -/// If \p Inverted is true then the check is for the inverted range, e.g. -/// (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n -Value *InstCombinerImpl::simplifyRangeCheck(ICmpInst *Cmp0, ICmpInst *Cmp1, - bool Inverted) { - // Check the lower range comparison, e.g. x >= 0 - // InstCombine already ensured that if there is a constant it's on the RHS. - ConstantInt *RangeStart = dyn_cast(Cmp0->getOperand(1)); - if (!RangeStart) - return nullptr; - - ICmpInst::Predicate Pred0 = (Inverted ? Cmp0->getInversePredicate() : - Cmp0->getPredicate()); - - // Accept x > -1 or x >= 0 (after potentially inverting the predicate). - if (!((Pred0 == ICmpInst::ICMP_SGT && RangeStart->isMinusOne()) || - (Pred0 == ICmpInst::ICMP_SGE && RangeStart->isZero()))) - return nullptr; - - ICmpInst::Predicate Pred1 = (Inverted ? Cmp1->getInversePredicate() : - Cmp1->getPredicate()); - - Value *Input = Cmp0->getOperand(0); - Value *Cmp1Op0 = Cmp1->getOperand(0); - Value *Cmp1Op1 = Cmp1->getOperand(1); - Value *RangeEnd; - if (match(Cmp1Op0, m_SExtOrSelf(m_Specific(Input)))) { - // For the upper range compare we have: icmp x, n - Input = Cmp1Op0; - RangeEnd = Cmp1Op1; - } else if (match(Cmp1Op1, m_SExtOrSelf(m_Specific(Input)))) { - // For the upper range compare we have: icmp n, x - Input = Cmp1Op1; - RangeEnd = Cmp1Op0; - Pred1 = ICmpInst::getSwappedPredicate(Pred1); - } else { - return nullptr; - } - - // Check the upper range comparison, e.g. x < n - ICmpInst::Predicate NewPred; - switch (Pred1) { - case ICmpInst::ICMP_SLT: NewPred = ICmpInst::ICMP_ULT; break; - case ICmpInst::ICMP_SLE: NewPred = ICmpInst::ICMP_ULE; break; - default: return nullptr; - } - - // This simplification is only valid if the upper range is not negative. - KnownBits Known = computeKnownBits(RangeEnd, /*Depth=*/0, Cmp1); - if (!Known.isNonNegative()) - return nullptr; - - if (Inverted) - NewPred = ICmpInst::getInversePredicate(NewPred); - - return Builder.CreateICmp(NewPred, Input, RangeEnd); -} - -// (or (icmp eq X, 0), (icmp eq X, Pow2OrZero)) -// -> (icmp eq (and X, Pow2OrZero), X) -// (and (icmp ne X, 0), (icmp ne X, Pow2OrZero)) -// -> (icmp ne (and X, Pow2OrZero), X) -static Value * -foldAndOrOfICmpsWithPow2AndWithZero(InstCombiner::BuilderTy &Builder, - ICmpInst *LHS, ICmpInst *RHS, bool IsAnd, - const SimplifyQuery &Q) { - CmpPredicate Pred = IsAnd ? CmpInst::ICMP_NE : CmpInst::ICMP_EQ; - // Make sure we have right compares for our op. - if (LHS->getPredicate() != Pred || RHS->getPredicate() != Pred) - return nullptr; - - // Make it so we can match LHS against the (icmp eq/ne X, 0) just for - // simplicity. - if (match(RHS->getOperand(1), m_Zero())) - std::swap(LHS, RHS); - - Value *Pow2, *Op; - // Match the desired pattern: - // LHS: (icmp eq/ne X, 0) - // RHS: (icmp eq/ne X, Pow2OrZero) - // Skip if Pow2OrZero is 1. Either way it gets folded to (icmp ugt X, 1) but - // this form ends up slightly less canonical. - // We could potentially be more sophisticated than requiring LHS/RHS - // be one-use. We don't create additional instructions if only one - // of them is one-use. So cases where one is one-use and the other - // is two-use might be profitable. - if (!match(LHS, m_OneUse(m_ICmp(Pred, m_Value(Op), m_Zero()))) || - !match(RHS, m_OneUse(m_c_ICmp(Pred, m_Specific(Op), m_Value(Pow2)))) || - match(Pow2, m_One()) || - !isKnownToBeAPowerOfTwo(Pow2, Q.DL, /*OrZero=*/true, /*Depth=*/0, Q.AC, - Q.CxtI, Q.DT)) - return nullptr; - - Value *And = Builder.CreateAnd(Op, Pow2); - return Builder.CreateICmp(Pred, And, Op); -} - -/// General pattern: -/// X & Y -/// -/// Where Y is checking that all the high bits (covered by a mask 4294967168) -/// are uniform, i.e. %arg & 4294967168 can be either 4294967168 or 0 -/// Pattern can be one of: -/// %t = add i32 %arg, 128 -/// %r = icmp ult i32 %t, 256 -/// Or -/// %t0 = shl i32 %arg, 24 -/// %t1 = ashr i32 %t0, 24 -/// %r = icmp eq i32 %t1, %arg -/// Or -/// %t0 = trunc i32 %arg to i8 -/// %t1 = sext i8 %t0 to i32 -/// %r = icmp eq i32 %t1, %arg -/// This pattern is a signed truncation check. -/// -/// And X is checking that some bit in that same mask is zero. -/// I.e. can be one of: -/// %r = icmp sgt i32 %arg, -1 -/// Or -/// %t = and i32 %arg, 2147483648 -/// %r = icmp eq i32 %t, 0 -/// -/// Since we are checking that all the bits in that mask are the same, -/// and a particular bit is zero, what we are really checking is that all the -/// masked bits are zero. -/// So this should be transformed to: -/// %r = icmp ult i32 %arg, 128 -static Value *foldSignedTruncationCheck(ICmpInst *ICmp0, ICmpInst *ICmp1, - Instruction &CxtI, - InstCombiner::BuilderTy &Builder) { - assert(CxtI.getOpcode() == Instruction::And); - - // Match icmp ult (add %arg, C01), C1 (C1 == C01 << 1; powers of two) - auto tryToMatchSignedTruncationCheck = [](ICmpInst *ICmp, Value *&X, - APInt &SignBitMask) -> bool { - const APInt *I01, *I1; // powers of two; I1 == I01 << 1 - if (!(match(ICmp, m_SpecificICmp(ICmpInst::ICMP_ULT, - m_Add(m_Value(X), m_Power2(I01)), - m_Power2(I1))) && - I1->ugt(*I01) && I01->shl(1) == *I1)) - return false; - // Which bit is the new sign bit as per the 'signed truncation' pattern? - SignBitMask = *I01; - return true; - }; - - // One icmp needs to be 'signed truncation check'. - // We need to match this first, else we will mismatch commutative cases. - Value *X1; - APInt HighestBit; - ICmpInst *OtherICmp; - if (tryToMatchSignedTruncationCheck(ICmp1, X1, HighestBit)) - OtherICmp = ICmp0; - else if (tryToMatchSignedTruncationCheck(ICmp0, X1, HighestBit)) - OtherICmp = ICmp1; - else - return nullptr; - - assert(HighestBit.isPowerOf2() && "expected to be power of two (non-zero)"); - - // Try to match/decompose into: icmp eq (X & Mask), 0 - auto tryToDecompose = [](ICmpInst *ICmp, Value *&X, - APInt &UnsetBitsMask) -> bool { - CmpPredicate Pred = ICmp->getPredicate(); - // Can it be decomposed into icmp eq (X & Mask), 0 ? - auto Res = - llvm::decomposeBitTestICmp(ICmp->getOperand(0), ICmp->getOperand(1), - Pred, /*LookThroughTrunc=*/false); - if (Res && Res->Pred == ICmpInst::ICMP_EQ) { - X = Res->X; - UnsetBitsMask = Res->Mask; - return true; - } - - // Is it icmp eq (X & Mask), 0 already? - const APInt *Mask; - if (match(ICmp, m_ICmp(Pred, m_And(m_Value(X), m_APInt(Mask)), m_Zero())) && - Pred == ICmpInst::ICMP_EQ) { - UnsetBitsMask = *Mask; - return true; - } - return false; - }; - - // And the other icmp needs to be decomposable into a bit test. - Value *X0; - APInt UnsetBitsMask; - if (!tryToDecompose(OtherICmp, X0, UnsetBitsMask)) - return nullptr; - - assert(!UnsetBitsMask.isZero() && "empty mask makes no sense."); - - // Are they working on the same value? - Value *X; - if (X1 == X0) { - // Ok as is. - X = X1; - } else if (match(X0, m_Trunc(m_Specific(X1)))) { - UnsetBitsMask = UnsetBitsMask.zext(X1->getType()->getScalarSizeInBits()); - X = X1; - } else - return nullptr; - - // So which bits should be uniform as per the 'signed truncation check'? - // (all the bits starting with (i.e. including) HighestBit) - APInt SignBitsMask = ~(HighestBit - 1U); - - // UnsetBitsMask must have some common bits with SignBitsMask, - if (!UnsetBitsMask.intersects(SignBitsMask)) - return nullptr; - - // Does UnsetBitsMask contain any bits outside of SignBitsMask? - if (!UnsetBitsMask.isSubsetOf(SignBitsMask)) { - APInt OtherHighestBit = (~UnsetBitsMask) + 1U; - if (!OtherHighestBit.isPowerOf2()) - return nullptr; - HighestBit = APIntOps::umin(HighestBit, OtherHighestBit); - } - // Else, if it does not, then all is ok as-is. - - // %r = icmp ult %X, SignBit - return Builder.CreateICmpULT(X, ConstantInt::get(X->getType(), HighestBit), - CxtI.getName() + ".simplified"); -} - -/// Fold (icmp eq ctpop(X) 1) | (icmp eq X 0) into (icmp ult ctpop(X) 2) and -/// fold (icmp ne ctpop(X) 1) & (icmp ne X 0) into (icmp ugt ctpop(X) 1). -/// Also used for logical and/or, must be poison safe if range attributes are -/// dropped. -static Value *foldIsPowerOf2OrZero(ICmpInst *Cmp0, ICmpInst *Cmp1, bool IsAnd, - InstCombiner::BuilderTy &Builder, - InstCombinerImpl &IC) { - CmpPredicate Pred0, Pred1; - Value *X; - if (!match(Cmp0, m_ICmp(Pred0, m_Intrinsic(m_Value(X)), - m_SpecificInt(1))) || - !match(Cmp1, m_ICmp(Pred1, m_Specific(X), m_ZeroInt()))) - return nullptr; - - auto *CtPop = cast(Cmp0->getOperand(0)); - if (IsAnd && Pred0 == ICmpInst::ICMP_NE && Pred1 == ICmpInst::ICMP_NE) { - // Drop range attributes and re-infer them in the next iteration. - CtPop->dropPoisonGeneratingAnnotations(); - IC.addToWorklist(CtPop); - return Builder.CreateICmpUGT(CtPop, ConstantInt::get(CtPop->getType(), 1)); - } - if (!IsAnd && Pred0 == ICmpInst::ICMP_EQ && Pred1 == ICmpInst::ICMP_EQ) { - // Drop range attributes and re-infer them in the next iteration. - CtPop->dropPoisonGeneratingAnnotations(); - IC.addToWorklist(CtPop); - return Builder.CreateICmpULT(CtPop, ConstantInt::get(CtPop->getType(), 2)); - } - - return nullptr; -} - -/// Reduce a pair of compares that check if a value has exactly 1 bit set. -/// Also used for logical and/or, must be poison safe if range attributes are -/// dropped. -static Value *foldIsPowerOf2(ICmpInst *Cmp0, ICmpInst *Cmp1, bool JoinedByAnd, - InstCombiner::BuilderTy &Builder, - InstCombinerImpl &IC) { - // Handle 'and' / 'or' commutation: make the equality check the first operand. - if (JoinedByAnd && Cmp1->getPredicate() == ICmpInst::ICMP_NE) - std::swap(Cmp0, Cmp1); - else if (!JoinedByAnd && Cmp1->getPredicate() == ICmpInst::ICMP_EQ) - std::swap(Cmp0, Cmp1); - - // (X != 0) && (ctpop(X) u< 2) --> ctpop(X) == 1 - Value *X; - if (JoinedByAnd && - match(Cmp0, m_SpecificICmp(ICmpInst::ICMP_NE, m_Value(X), m_ZeroInt())) && - match(Cmp1, m_SpecificICmp(ICmpInst::ICMP_ULT, - m_Intrinsic(m_Specific(X)), - m_SpecificInt(2)))) { - auto *CtPop = cast(Cmp1->getOperand(0)); - // Drop range attributes and re-infer them in the next iteration. - CtPop->dropPoisonGeneratingAnnotations(); - IC.addToWorklist(CtPop); - return Builder.CreateICmpEQ(CtPop, ConstantInt::get(CtPop->getType(), 1)); - } - // (X == 0) || (ctpop(X) u> 1) --> ctpop(X) != 1 - if (!JoinedByAnd && - match(Cmp0, m_SpecificICmp(ICmpInst::ICMP_EQ, m_Value(X), m_ZeroInt())) && - match(Cmp1, m_SpecificICmp(ICmpInst::ICMP_UGT, - m_Intrinsic(m_Specific(X)), - m_SpecificInt(1)))) { - auto *CtPop = cast(Cmp1->getOperand(0)); - // Drop range attributes and re-infer them in the next iteration. - CtPop->dropPoisonGeneratingAnnotations(); - IC.addToWorklist(CtPop); - return Builder.CreateICmpNE(CtPop, ConstantInt::get(CtPop->getType(), 1)); - } - return nullptr; -} - -/// Try to fold (icmp(A & B) == 0) & (icmp(A & D) != E) into (icmp A u< D) iff -/// B is a contiguous set of ones starting from the most significant bit -/// (negative power of 2), D and E are equal, and D is a contiguous set of ones -/// starting at the most significant zero bit in B. Parameter B supports masking -/// using undef/poison in either scalar or vector values. -static Value *foldNegativePower2AndShiftedMask( - Value *A, Value *B, Value *D, Value *E, ICmpInst::Predicate PredL, - ICmpInst::Predicate PredR, InstCombiner::BuilderTy &Builder) { - assert(ICmpInst::isEquality(PredL) && ICmpInst::isEquality(PredR) && - "Expected equality predicates for masked type of icmps."); - if (PredL != ICmpInst::ICMP_EQ || PredR != ICmpInst::ICMP_NE) - return nullptr; - - if (!match(B, m_NegatedPower2()) || !match(D, m_ShiftedMask()) || - !match(E, m_ShiftedMask())) - return nullptr; - - // Test scalar arguments for conversion. B has been validated earlier to be a - // negative power of two and thus is guaranteed to have one or more contiguous - // ones starting from the MSB followed by zero or more contiguous zeros. D has - // been validated earlier to be a shifted set of one or more contiguous ones. - // In order to match, B leading ones and D leading zeros should be equal. The - // predicate that B be a negative power of 2 prevents the condition of there - // ever being zero leading ones. Thus 0 == 0 cannot occur. The predicate that - // D always be a shifted mask prevents the condition of D equaling 0. This - // prevents matching the condition where B contains the maximum number of - // leading one bits (-1) and D contains the maximum number of leading zero - // bits (0). - auto isReducible = [](const Value *B, const Value *D, const Value *E) { - const APInt *BCst, *DCst, *ECst; - return match(B, m_APIntAllowPoison(BCst)) && match(D, m_APInt(DCst)) && - match(E, m_APInt(ECst)) && *DCst == *ECst && - (isa(B) || - (BCst->countLeadingOnes() == DCst->countLeadingZeros())); - }; - - // Test vector type arguments for conversion. - if (const auto *BVTy = dyn_cast(B->getType())) { - const auto *BFVTy = dyn_cast(BVTy); - const auto *BConst = dyn_cast(B); - const auto *DConst = dyn_cast(D); - const auto *EConst = dyn_cast(E); - - if (!BFVTy || !BConst || !DConst || !EConst) - return nullptr; - - for (unsigned I = 0; I != BFVTy->getNumElements(); ++I) { - const auto *BElt = BConst->getAggregateElement(I); - const auto *DElt = DConst->getAggregateElement(I); - const auto *EElt = EConst->getAggregateElement(I); - - if (!BElt || !DElt || !EElt) - return nullptr; - if (!isReducible(BElt, DElt, EElt)) - return nullptr; - } - } else { - // Test scalar type arguments for conversion. - if (!isReducible(B, D, E)) - return nullptr; - } - return Builder.CreateICmp(ICmpInst::ICMP_ULT, A, D); -} - -/// Try to fold ((icmp X u< P) & (icmp(X & M) != M)) or ((icmp X s> -1) & -/// (icmp(X & M) != M)) into (icmp X u< M). Where P is a power of 2, M < P, and -/// M is a contiguous shifted mask starting at the right most significant zero -/// bit in P. SGT is supported as when P is the largest representable power of -/// 2, an earlier optimization converts the expression into (icmp X s> -1). -/// Parameter P supports masking using undef/poison in either scalar or vector -/// values. -static Value *foldPowerOf2AndShiftedMask(ICmpInst *Cmp0, ICmpInst *Cmp1, - bool JoinedByAnd, - InstCombiner::BuilderTy &Builder) { - if (!JoinedByAnd) - return nullptr; - Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr; - ICmpInst::Predicate CmpPred0, CmpPred1; - // Assuming P is a 2^n, getMaskedTypeForICmpPair will normalize (icmp X u< - // 2^n) into (icmp (X & ~(2^n-1)) == 0) and (icmp X s> -1) into (icmp (X & - // SignMask) == 0). - std::optional> MaskPair = - getMaskedTypeForICmpPair(A, B, C, D, E, Cmp0, Cmp1, CmpPred0, CmpPred1); - if (!MaskPair) - return nullptr; - - const auto compareBMask = BMask_NotMixed | BMask_NotAllOnes; - unsigned CmpMask0 = MaskPair->first; - unsigned CmpMask1 = MaskPair->second; - if ((CmpMask0 & Mask_AllZeros) && (CmpMask1 == compareBMask)) { - if (Value *V = foldNegativePower2AndShiftedMask(A, B, D, E, CmpPred0, - CmpPred1, Builder)) - return V; - } else if ((CmpMask0 == compareBMask) && (CmpMask1 & Mask_AllZeros)) { - if (Value *V = foldNegativePower2AndShiftedMask(A, D, B, C, CmpPred1, - CmpPred0, Builder)) - return V; - } - return nullptr; -} - -/// Commuted variants are assumed to be handled by calling this function again -/// with the parameters swapped. -static Value *foldUnsignedUnderflowCheck(ICmpInst *ZeroICmp, - ICmpInst *UnsignedICmp, bool IsAnd, - const SimplifyQuery &Q, - InstCombiner::BuilderTy &Builder) { - Value *ZeroCmpOp; - CmpPredicate EqPred; - if (!match(ZeroICmp, m_ICmp(EqPred, m_Value(ZeroCmpOp), m_Zero())) || - !ICmpInst::isEquality(EqPred)) - return nullptr; - - CmpPredicate UnsignedPred; - - Value *A, *B; - if (match(UnsignedICmp, - m_c_ICmp(UnsignedPred, m_Specific(ZeroCmpOp), m_Value(A))) && - match(ZeroCmpOp, m_c_Add(m_Specific(A), m_Value(B))) && - (ZeroICmp->hasOneUse() || UnsignedICmp->hasOneUse())) { - auto GetKnownNonZeroAndOther = [&](Value *&NonZero, Value *&Other) { - if (!isKnownNonZero(NonZero, Q)) - std::swap(NonZero, Other); - return isKnownNonZero(NonZero, Q); - }; - - // Given ZeroCmpOp = (A + B) - // ZeroCmpOp < A && ZeroCmpOp != 0 --> (0-X) < Y iff - // ZeroCmpOp >= A || ZeroCmpOp == 0 --> (0-X) >= Y iff - // with X being the value (A/B) that is known to be non-zero, - // and Y being remaining value. - if (UnsignedPred == ICmpInst::ICMP_ULT && EqPred == ICmpInst::ICMP_NE && - IsAnd && GetKnownNonZeroAndOther(B, A)) - return Builder.CreateICmpULT(Builder.CreateNeg(B), A); - if (UnsignedPred == ICmpInst::ICMP_UGE && EqPred == ICmpInst::ICMP_EQ && - !IsAnd && GetKnownNonZeroAndOther(B, A)) - return Builder.CreateICmpUGE(Builder.CreateNeg(B), A); - } - - return nullptr; -} - -struct IntPart { - Value *From; - unsigned StartBit; - unsigned NumBits; -}; - -/// Match an extraction of bits from an integer. -static std::optional matchIntPart(Value *V) { - Value *X; - if (!match(V, m_OneUse(m_Trunc(m_Value(X))))) - return std::nullopt; - - unsigned NumOriginalBits = X->getType()->getScalarSizeInBits(); - unsigned NumExtractedBits = V->getType()->getScalarSizeInBits(); - Value *Y; - const APInt *Shift; - // For a trunc(lshr Y, Shift) pattern, make sure we're only extracting bits - // from Y, not any shifted-in zeroes. - if (match(X, m_OneUse(m_LShr(m_Value(Y), m_APInt(Shift)))) && - Shift->ule(NumOriginalBits - NumExtractedBits)) - return {{Y, (unsigned)Shift->getZExtValue(), NumExtractedBits}}; - return {{X, 0, NumExtractedBits}}; -} - -/// Materialize an extraction of bits from an integer in IR. -static Value *extractIntPart(const IntPart &P, IRBuilderBase &Builder) { - Value *V = P.From; - if (P.StartBit) - V = Builder.CreateLShr(V, P.StartBit); - Type *TruncTy = V->getType()->getWithNewBitWidth(P.NumBits); - if (TruncTy != V->getType()) - V = Builder.CreateTrunc(V, TruncTy); - return V; -} - -/// (icmp eq X0, Y0) & (icmp eq X1, Y1) -> icmp eq X01, Y01 -/// (icmp ne X0, Y0) | (icmp ne X1, Y1) -> icmp ne X01, Y01 -/// where X0, X1 and Y0, Y1 are adjacent parts extracted from an integer. -Value *InstCombinerImpl::foldEqOfParts(Value *Cmp0, Value *Cmp1, bool IsAnd) { - if (!Cmp0->hasOneUse() || !Cmp1->hasOneUse()) - return nullptr; - - CmpInst::Predicate Pred = IsAnd ? CmpInst::ICMP_EQ : CmpInst::ICMP_NE; - auto GetMatchPart = [&](Value *CmpV, - unsigned OpNo) -> std::optional { - assert(CmpV->getType()->isIntOrIntVectorTy(1) && "Must be bool"); - - Value *X, *Y; - // icmp ne (and x, 1), (and y, 1) <=> trunc (xor x, y) to i1 - // icmp eq (and x, 1), (and y, 1) <=> not (trunc (xor x, y) to i1) - if (Pred == CmpInst::ICMP_NE - ? match(CmpV, m_Trunc(m_Xor(m_Value(X), m_Value(Y)))) - : match(CmpV, m_Not(m_Trunc(m_Xor(m_Value(X), m_Value(Y)))))) - return {{OpNo == 0 ? X : Y, 0, 1}}; - - auto *Cmp = dyn_cast(CmpV); - if (!Cmp) - return std::nullopt; - - if (Pred == Cmp->getPredicate()) - return matchIntPart(Cmp->getOperand(OpNo)); - - const APInt *C; - // (icmp eq (lshr x, C), (lshr y, C)) gets optimized to: - // (icmp ult (xor x, y), 1 << C) so also look for that. - if (Pred == CmpInst::ICMP_EQ && Cmp->getPredicate() == CmpInst::ICMP_ULT) { - if (!match(Cmp->getOperand(1), m_Power2(C)) || - !match(Cmp->getOperand(0), m_Xor(m_Value(), m_Value()))) - return std::nullopt; - } - - // (icmp ne (lshr x, C), (lshr y, C)) gets optimized to: - // (icmp ugt (xor x, y), (1 << C) - 1) so also look for that. - else if (Pred == CmpInst::ICMP_NE && - Cmp->getPredicate() == CmpInst::ICMP_UGT) { - if (!match(Cmp->getOperand(1), m_LowBitMask(C)) || - !match(Cmp->getOperand(0), m_Xor(m_Value(), m_Value()))) - return std::nullopt; - } else { - return std::nullopt; - } - - unsigned From = Pred == CmpInst::ICMP_NE ? C->popcount() : C->countr_zero(); - Instruction *I = cast(Cmp->getOperand(0)); - return {{I->getOperand(OpNo), From, C->getBitWidth() - From}}; - }; - - std::optional L0 = GetMatchPart(Cmp0, 0); - std::optional R0 = GetMatchPart(Cmp0, 1); - std::optional L1 = GetMatchPart(Cmp1, 0); - std::optional R1 = GetMatchPart(Cmp1, 1); - if (!L0 || !R0 || !L1 || !R1) - return nullptr; - - // Make sure the LHS/RHS compare a part of the same value, possibly after - // an operand swap. - if (L0->From != L1->From || R0->From != R1->From) { - if (L0->From != R1->From || R0->From != L1->From) - return nullptr; - std::swap(L1, R1); - } - - // Make sure the extracted parts are adjacent, canonicalizing to L0/R0 being - // the low part and L1/R1 being the high part. - if (L0->StartBit + L0->NumBits != L1->StartBit || - R0->StartBit + R0->NumBits != R1->StartBit) { - if (L1->StartBit + L1->NumBits != L0->StartBit || - R1->StartBit + R1->NumBits != R0->StartBit) - return nullptr; - std::swap(L0, L1); - std::swap(R0, R1); - } - - // We can simplify to a comparison of these larger parts of the integers. - IntPart L = {L0->From, L0->StartBit, L0->NumBits + L1->NumBits}; - IntPart R = {R0->From, R0->StartBit, R0->NumBits + R1->NumBits}; - Value *LValue = extractIntPart(L, Builder); - Value *RValue = extractIntPart(R, Builder); - return Builder.CreateICmp(Pred, LValue, RValue); -} - -/// Reduce logic-of-compares with equality to a constant by substituting a -/// common operand with the constant. Callers are expected to call this with -/// Cmp0/Cmp1 switched to handle logic op commutativity. -static Value *foldAndOrOfICmpsWithConstEq(ICmpInst *Cmp0, ICmpInst *Cmp1, - bool IsAnd, bool IsLogical, - InstCombiner::BuilderTy &Builder, - const SimplifyQuery &Q) { - // Match an equality compare with a non-poison constant as Cmp0. - // Also, give up if the compare can be constant-folded to avoid looping. - CmpPredicate Pred0; - Value *X; - Constant *C; - if (!match(Cmp0, m_ICmp(Pred0, m_Value(X), m_Constant(C))) || - !isGuaranteedNotToBeUndefOrPoison(C) || isa(X)) - return nullptr; - if ((IsAnd && Pred0 != ICmpInst::ICMP_EQ) || - (!IsAnd && Pred0 != ICmpInst::ICMP_NE)) - return nullptr; - - // The other compare must include a common operand (X). Canonicalize the - // common operand as operand 1 (Pred1 is swapped if the common operand was - // operand 0). - Value *Y; - CmpPredicate Pred1; - if (!match(Cmp1, m_c_ICmp(Pred1, m_Value(Y), m_Specific(X)))) - return nullptr; - - // Replace variable with constant value equivalence to remove a variable use: - // (X == C) && (Y Pred1 X) --> (X == C) && (Y Pred1 C) - // (X != C) || (Y Pred1 X) --> (X != C) || (Y Pred1 C) - // Can think of the 'or' substitution with the 'and' bool equivalent: - // A || B --> A || (!A && B) - Value *SubstituteCmp = simplifyICmpInst(Pred1, Y, C, Q); - if (!SubstituteCmp) { - // If we need to create a new instruction, require that the old compare can - // be removed. - if (!Cmp1->hasOneUse()) - return nullptr; - SubstituteCmp = Builder.CreateICmp(Pred1, Y, C); - } - if (IsLogical) - return IsAnd ? Builder.CreateLogicalAnd(Cmp0, SubstituteCmp) - : Builder.CreateLogicalOr(Cmp0, SubstituteCmp); - return Builder.CreateBinOp(IsAnd ? Instruction::And : Instruction::Or, Cmp0, - SubstituteCmp); -} - -/// Fold (icmp Pred1 V1, C1) & (icmp Pred2 V2, C2) -/// or (icmp Pred1 V1, C1) | (icmp Pred2 V2, C2) -/// into a single comparison using range-based reasoning. -/// NOTE: This is also used for logical and/or, must be poison-safe! -Value *InstCombinerImpl::foldAndOrOfICmpsUsingRanges(ICmpInst *ICmp1, - ICmpInst *ICmp2, - bool IsAnd) { - CmpPredicate Pred1, Pred2; - Value *V1, *V2; - const APInt *C1, *C2; - if (!match(ICmp1, m_ICmp(Pred1, m_Value(V1), m_APInt(C1))) || - !match(ICmp2, m_ICmp(Pred2, m_Value(V2), m_APInt(C2)))) - return nullptr; - - // Look through add of a constant offset on V1, V2, or both operands. This - // allows us to interpret the V + C' < C'' range idiom into a proper range. - const APInt *Offset1 = nullptr, *Offset2 = nullptr; - if (V1 != V2) { - Value *X; - if (match(V1, m_Add(m_Value(X), m_APInt(Offset1)))) - V1 = X; - if (match(V2, m_Add(m_Value(X), m_APInt(Offset2)))) - V2 = X; - } - - if (V1 != V2) - return nullptr; - - ConstantRange CR1 = ConstantRange::makeExactICmpRegion( - IsAnd ? ICmpInst::getInverseCmpPredicate(Pred1) : Pred1, *C1); - if (Offset1) - CR1 = CR1.subtract(*Offset1); - - ConstantRange CR2 = ConstantRange::makeExactICmpRegion( - IsAnd ? ICmpInst::getInverseCmpPredicate(Pred2) : Pred2, *C2); - if (Offset2) - CR2 = CR2.subtract(*Offset2); - - Type *Ty = V1->getType(); - Value *NewV = V1; - std::optional CR = CR1.exactUnionWith(CR2); - if (!CR) { - if (!(ICmp1->hasOneUse() && ICmp2->hasOneUse()) || CR1.isWrappedSet() || - CR2.isWrappedSet()) - return nullptr; - - // Check whether we have equal-size ranges that only differ by one bit. - // In that case we can apply a mask to map one range onto the other. - APInt LowerDiff = CR1.getLower() ^ CR2.getLower(); - APInt UpperDiff = (CR1.getUpper() - 1) ^ (CR2.getUpper() - 1); - APInt CR1Size = CR1.getUpper() - CR1.getLower(); - if (!LowerDiff.isPowerOf2() || LowerDiff != UpperDiff || - CR1Size != CR2.getUpper() - CR2.getLower()) - return nullptr; - - CR = CR1.getLower().ult(CR2.getLower()) ? CR1 : CR2; - NewV = Builder.CreateAnd(NewV, ConstantInt::get(Ty, ~LowerDiff)); - } - - if (IsAnd) - CR = CR->inverse(); - - CmpInst::Predicate NewPred; - APInt NewC, Offset; - CR->getEquivalentICmp(NewPred, NewC, Offset); - - if (Offset != 0) - NewV = Builder.CreateAdd(NewV, ConstantInt::get(Ty, Offset)); - return Builder.CreateICmp(NewPred, NewV, ConstantInt::get(Ty, NewC)); -} - -/// Ignore all operations which only change the sign of a value, returning the -/// underlying magnitude value. -static Value *stripSignOnlyFPOps(Value *Val) { - match(Val, m_FNeg(m_Value(Val))); - match(Val, m_FAbs(m_Value(Val))); - match(Val, m_CopySign(m_Value(Val), m_Value())); - return Val; -} - -/// Matches canonical form of isnan, fcmp ord x, 0 -static bool matchIsNotNaN(FCmpInst::Predicate P, Value *LHS, Value *RHS) { - return P == FCmpInst::FCMP_ORD && match(RHS, m_AnyZeroFP()); -} - -/// Matches fcmp u__ x, +/-inf -static bool matchUnorderedInfCompare(FCmpInst::Predicate P, Value *LHS, - Value *RHS) { - return FCmpInst::isUnordered(P) && match(RHS, m_Inf()); -} - -/// and (fcmp ord x, 0), (fcmp u* x, inf) -> fcmp o* x, inf -/// -/// Clang emits this pattern for doing an isfinite check in __builtin_isnormal. -static Value *matchIsFiniteTest(InstCombiner::BuilderTy &Builder, FCmpInst *LHS, - FCmpInst *RHS) { - Value *LHS0 = LHS->getOperand(0), *LHS1 = LHS->getOperand(1); - Value *RHS0 = RHS->getOperand(0), *RHS1 = RHS->getOperand(1); - FCmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate(); - - if (!matchIsNotNaN(PredL, LHS0, LHS1) || - !matchUnorderedInfCompare(PredR, RHS0, RHS1)) - return nullptr; - - return Builder.CreateFCmpFMF(FCmpInst::getOrderedPredicate(PredR), RHS0, RHS1, - FMFSource::intersect(LHS, RHS)); -} - -Value *InstCombinerImpl::foldLogicOfFCmps(FCmpInst *LHS, FCmpInst *RHS, - bool IsAnd, bool IsLogicalSelect) { - Value *LHS0 = LHS->getOperand(0), *LHS1 = LHS->getOperand(1); - Value *RHS0 = RHS->getOperand(0), *RHS1 = RHS->getOperand(1); - FCmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate(); - - if (LHS0 == RHS1 && RHS0 == LHS1) { - // Swap RHS operands to match LHS. - PredR = FCmpInst::getSwappedPredicate(PredR); - std::swap(RHS0, RHS1); - } - - // Simplify (fcmp cc0 x, y) & (fcmp cc1 x, y). - // Suppose the relation between x and y is R, where R is one of - // U(1000), L(0100), G(0010) or E(0001), and CC0 and CC1 are the bitmasks for - // testing the desired relations. - // - // Since (R & CC0) and (R & CC1) are either R or 0, we actually have this: - // bool(R & CC0) && bool(R & CC1) - // = bool((R & CC0) & (R & CC1)) - // = bool(R & (CC0 & CC1)) <= by re-association, commutation, and idempotency - // - // Since (R & CC0) and (R & CC1) are either R or 0, we actually have this: - // bool(R & CC0) || bool(R & CC1) - // = bool((R & CC0) | (R & CC1)) - // = bool(R & (CC0 | CC1)) <= by reversed distribution (contribution? ;) - if (LHS0 == RHS0 && LHS1 == RHS1) { - unsigned FCmpCodeL = getFCmpCode(PredL); - unsigned FCmpCodeR = getFCmpCode(PredR); - unsigned NewPred = IsAnd ? FCmpCodeL & FCmpCodeR : FCmpCodeL | FCmpCodeR; - - // Intersect the fast math flags. - // TODO: We can union the fast math flags unless this is a logical select. - return getFCmpValue(NewPred, LHS0, LHS1, Builder, - FMFSource::intersect(LHS, RHS)); - } - - // This transform is not valid for a logical select. - if (!IsLogicalSelect && - ((PredL == FCmpInst::FCMP_ORD && PredR == FCmpInst::FCMP_ORD && IsAnd) || - (PredL == FCmpInst::FCMP_UNO && PredR == FCmpInst::FCMP_UNO && - !IsAnd))) { - if (LHS0->getType() != RHS0->getType()) - return nullptr; - - // FCmp canonicalization ensures that (fcmp ord/uno X, X) and - // (fcmp ord/uno X, C) will be transformed to (fcmp X, +0.0). - if (match(LHS1, m_PosZeroFP()) && match(RHS1, m_PosZeroFP())) { - // Ignore the constants because they are obviously not NANs: - // (fcmp ord x, 0.0) & (fcmp ord y, 0.0) -> (fcmp ord x, y) - // (fcmp uno x, 0.0) | (fcmp uno y, 0.0) -> (fcmp uno x, y) - return Builder.CreateFCmpFMF(PredL, LHS0, RHS0, - FMFSource::intersect(LHS, RHS)); - } - } - - if (IsAnd && stripSignOnlyFPOps(LHS0) == stripSignOnlyFPOps(RHS0)) { - // and (fcmp ord x, 0), (fcmp u* x, inf) -> fcmp o* x, inf - // and (fcmp ord x, 0), (fcmp u* fabs(x), inf) -> fcmp o* x, inf - if (Value *Left = matchIsFiniteTest(Builder, LHS, RHS)) - return Left; - if (Value *Right = matchIsFiniteTest(Builder, RHS, LHS)) - return Right; - } - - // Turn at least two fcmps with constants into llvm.is.fpclass. - // - // If we can represent a combined value test with one class call, we can - // potentially eliminate 4-6 instructions. If we can represent a test with a - // single fcmp with fneg and fabs, that's likely a better canonical form. - if (LHS->hasOneUse() && RHS->hasOneUse()) { - auto [ClassValRHS, ClassMaskRHS] = - fcmpToClassTest(PredR, *RHS->getFunction(), RHS0, RHS1); - if (ClassValRHS) { - auto [ClassValLHS, ClassMaskLHS] = - fcmpToClassTest(PredL, *LHS->getFunction(), LHS0, LHS1); - if (ClassValLHS == ClassValRHS) { - unsigned CombinedMask = IsAnd ? (ClassMaskLHS & ClassMaskRHS) - : (ClassMaskLHS | ClassMaskRHS); - return Builder.CreateIntrinsic( - Intrinsic::is_fpclass, {ClassValLHS->getType()}, - {ClassValLHS, Builder.getInt32(CombinedMask)}); - } - } - } - - // Canonicalize the range check idiom: - // and (fcmp olt/ole/ult/ule x, C), (fcmp ogt/oge/ugt/uge x, -C) - // --> fabs(x) olt/ole/ult/ule C - // or (fcmp ogt/oge/ugt/uge x, C), (fcmp olt/ole/ult/ule x, -C) - // --> fabs(x) ogt/oge/ugt/uge C - // TODO: Generalize to handle a negated variable operand? - const APFloat *LHSC, *RHSC; - if (LHS0 == RHS0 && LHS->hasOneUse() && RHS->hasOneUse() && - FCmpInst::getSwappedPredicate(PredL) == PredR && - match(LHS1, m_APFloatAllowPoison(LHSC)) && - match(RHS1, m_APFloatAllowPoison(RHSC)) && - LHSC->bitwiseIsEqual(neg(*RHSC))) { - auto IsLessThanOrLessEqual = [](FCmpInst::Predicate Pred) { - switch (Pred) { - case FCmpInst::FCMP_OLT: - case FCmpInst::FCMP_OLE: - case FCmpInst::FCMP_ULT: - case FCmpInst::FCMP_ULE: - return true; - default: - return false; - } - }; - if (IsLessThanOrLessEqual(IsAnd ? PredR : PredL)) { - std::swap(LHSC, RHSC); - std::swap(PredL, PredR); - } - if (IsLessThanOrLessEqual(IsAnd ? PredL : PredR)) { - FastMathFlags NewFlag = LHS->getFastMathFlags(); - if (!IsLogicalSelect) - NewFlag |= RHS->getFastMathFlags(); - - Value *FAbs = - Builder.CreateUnaryIntrinsic(Intrinsic::fabs, LHS0, NewFlag); - return Builder.CreateFCmpFMF( - PredL, FAbs, ConstantFP::get(LHS0->getType(), *LHSC), NewFlag); - } - } - - return nullptr; -} - -/// Match an fcmp against a special value that performs a test possible by -/// llvm.is.fpclass. -static bool matchIsFPClassLikeFCmp(Value *Op, Value *&ClassVal, - uint64_t &ClassMask) { - auto *FCmp = dyn_cast(Op); - if (!FCmp || !FCmp->hasOneUse()) - return false; - - std::tie(ClassVal, ClassMask) = - fcmpToClassTest(FCmp->getPredicate(), *FCmp->getParent()->getParent(), - FCmp->getOperand(0), FCmp->getOperand(1)); - return ClassVal != nullptr; -} - -/// or (is_fpclass x, mask0), (is_fpclass x, mask1) -/// -> is_fpclass x, (mask0 | mask1) -/// and (is_fpclass x, mask0), (is_fpclass x, mask1) -/// -> is_fpclass x, (mask0 & mask1) -/// xor (is_fpclass x, mask0), (is_fpclass x, mask1) -/// -> is_fpclass x, (mask0 ^ mask1) -Instruction *InstCombinerImpl::foldLogicOfIsFPClass(BinaryOperator &BO, - Value *Op0, Value *Op1) { - Value *ClassVal0 = nullptr; - Value *ClassVal1 = nullptr; - uint64_t ClassMask0, ClassMask1; - - // Restrict to folding one fcmp into one is.fpclass for now, don't introduce a - // new class. - // - // TODO: Support forming is.fpclass out of 2 separate fcmps when codegen is - // better. - - bool IsLHSClass = - match(Op0, m_OneUse(m_Intrinsic( - m_Value(ClassVal0), m_ConstantInt(ClassMask0)))); - bool IsRHSClass = - match(Op1, m_OneUse(m_Intrinsic( - m_Value(ClassVal1), m_ConstantInt(ClassMask1)))); - if ((((IsLHSClass || matchIsFPClassLikeFCmp(Op0, ClassVal0, ClassMask0)) && - (IsRHSClass || matchIsFPClassLikeFCmp(Op1, ClassVal1, ClassMask1)))) && - ClassVal0 == ClassVal1) { - unsigned NewClassMask; - switch (BO.getOpcode()) { - case Instruction::And: - NewClassMask = ClassMask0 & ClassMask1; - break; - case Instruction::Or: - NewClassMask = ClassMask0 | ClassMask1; - break; - case Instruction::Xor: - NewClassMask = ClassMask0 ^ ClassMask1; - break; - default: - llvm_unreachable("not a binary logic operator"); - } - - if (IsLHSClass) { - auto *II = cast(Op0); - II->setArgOperand( - 1, ConstantInt::get(II->getArgOperand(1)->getType(), NewClassMask)); - return replaceInstUsesWith(BO, II); - } - - if (IsRHSClass) { - auto *II = cast(Op1); - II->setArgOperand( - 1, ConstantInt::get(II->getArgOperand(1)->getType(), NewClassMask)); - return replaceInstUsesWith(BO, II); - } - - CallInst *NewClass = - Builder.CreateIntrinsic(Intrinsic::is_fpclass, {ClassVal0->getType()}, - {ClassVal0, Builder.getInt32(NewClassMask)}); - return replaceInstUsesWith(BO, NewClass); - } - - return nullptr; -} - -/// Look for the pattern that conditionally negates a value via math operations: -/// cond.splat = sext i1 cond -/// sub = add cond.splat, x -/// xor = xor sub, cond.splat -/// and rewrite it to do the same, but via logical operations: -/// value.neg = sub 0, value -/// cond = select i1 neg, value.neg, value -Instruction *InstCombinerImpl::canonicalizeConditionalNegationViaMathToSelect( - BinaryOperator &I) { - assert(I.getOpcode() == BinaryOperator::Xor && "Only for xor!"); - Value *Cond, *X; - // As per complexity ordering, `xor` is not commutative here. - if (!match(&I, m_c_BinOp(m_OneUse(m_Value()), m_Value())) || - !match(I.getOperand(1), m_SExt(m_Value(Cond))) || - !Cond->getType()->isIntOrIntVectorTy(1) || - !match(I.getOperand(0), m_c_Add(m_SExt(m_Specific(Cond)), m_Value(X)))) - return nullptr; - return SelectInst::Create(Cond, Builder.CreateNeg(X, X->getName() + ".neg"), - X); -} - -/// This a limited reassociation for a special case (see above) where we are -/// checking if two values are either both NAN (unordered) or not-NAN (ordered). -/// This could be handled more generally in '-reassociation', but it seems like -/// an unlikely pattern for a large number of logic ops and fcmps. -static Instruction *reassociateFCmps(BinaryOperator &BO, - InstCombiner::BuilderTy &Builder) { - Instruction::BinaryOps Opcode = BO.getOpcode(); - assert((Opcode == Instruction::And || Opcode == Instruction::Or) && - "Expecting and/or op for fcmp transform"); - - // There are 4 commuted variants of the pattern. Canonicalize operands of this - // logic op so an fcmp is operand 0 and a matching logic op is operand 1. - Value *Op0 = BO.getOperand(0), *Op1 = BO.getOperand(1), *X; - if (match(Op1, m_FCmp(m_Value(), m_AnyZeroFP()))) - std::swap(Op0, Op1); - - // Match inner binop and the predicate for combining 2 NAN checks into 1. - Value *BO10, *BO11; - FCmpInst::Predicate NanPred = Opcode == Instruction::And ? FCmpInst::FCMP_ORD - : FCmpInst::FCMP_UNO; - if (!match(Op0, m_SpecificFCmp(NanPred, m_Value(X), m_AnyZeroFP())) || - !match(Op1, m_BinOp(Opcode, m_Value(BO10), m_Value(BO11)))) - return nullptr; - - // The inner logic op must have a matching fcmp operand. - Value *Y; - if (!match(BO10, m_SpecificFCmp(NanPred, m_Value(Y), m_AnyZeroFP())) || - X->getType() != Y->getType()) - std::swap(BO10, BO11); - - if (!match(BO10, m_SpecificFCmp(NanPred, m_Value(Y), m_AnyZeroFP())) || - X->getType() != Y->getType()) - return nullptr; - - // and (fcmp ord X, 0), (and (fcmp ord Y, 0), Z) --> and (fcmp ord X, Y), Z - // or (fcmp uno X, 0), (or (fcmp uno Y, 0), Z) --> or (fcmp uno X, Y), Z - // Intersect FMF from the 2 source fcmps. - Value *NewFCmp = - Builder.CreateFCmpFMF(NanPred, X, Y, FMFSource::intersect(Op0, BO10)); - return BinaryOperator::Create(Opcode, NewFCmp, BO11); -} - -/// Match variations of De Morgan's Laws: -/// (~A & ~B) == (~(A | B)) -/// (~A | ~B) == (~(A & B)) -static Instruction *matchDeMorgansLaws(BinaryOperator &I, - InstCombiner &IC) { - const Instruction::BinaryOps Opcode = I.getOpcode(); - assert((Opcode == Instruction::And || Opcode == Instruction::Or) && - "Trying to match De Morgan's Laws with something other than and/or"); - - // Flip the logic operation. - const Instruction::BinaryOps FlippedOpcode = - (Opcode == Instruction::And) ? Instruction::Or : Instruction::And; - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - Value *A, *B; - if (match(Op0, m_OneUse(m_Not(m_Value(A)))) && - match(Op1, m_OneUse(m_Not(m_Value(B)))) && - !IC.isFreeToInvert(A, A->hasOneUse()) && - !IC.isFreeToInvert(B, B->hasOneUse())) { - Value *AndOr = - IC.Builder.CreateBinOp(FlippedOpcode, A, B, I.getName() + ".demorgan"); - return BinaryOperator::CreateNot(AndOr); - } - - // The 'not' ops may require reassociation. - // (A & ~B) & ~C --> A & ~(B | C) - // (~B & A) & ~C --> A & ~(B | C) - // (A | ~B) | ~C --> A | ~(B & C) - // (~B | A) | ~C --> A | ~(B & C) - Value *C; - if (match(Op0, m_OneUse(m_c_BinOp(Opcode, m_Value(A), m_Not(m_Value(B))))) && - match(Op1, m_Not(m_Value(C)))) { - Value *FlippedBO = IC.Builder.CreateBinOp(FlippedOpcode, B, C); - return BinaryOperator::Create(Opcode, A, IC.Builder.CreateNot(FlippedBO)); - } - - return nullptr; -} - -bool InstCombinerImpl::shouldOptimizeCast(CastInst *CI) { - Value *CastSrc = CI->getOperand(0); - - // Noop casts and casts of constants should be eliminated trivially. - if (CI->getSrcTy() == CI->getDestTy() || isa(CastSrc)) - return false; - - // If this cast is paired with another cast that can be eliminated, we prefer - // to have it eliminated. - if (const auto *PrecedingCI = dyn_cast(CastSrc)) - if (isEliminableCastPair(PrecedingCI, CI)) - return false; - - return true; -} - -/// Fold {and,or,xor} (cast X), C. -static Instruction *foldLogicCastConstant(BinaryOperator &Logic, CastInst *Cast, - InstCombinerImpl &IC) { - Constant *C = dyn_cast(Logic.getOperand(1)); - if (!C) - return nullptr; - - auto LogicOpc = Logic.getOpcode(); - Type *DestTy = Logic.getType(); - Type *SrcTy = Cast->getSrcTy(); - - // Move the logic operation ahead of a zext or sext if the constant is - // unchanged in the smaller source type. Performing the logic in a smaller - // type may provide more information to later folds, and the smaller logic - // instruction may be cheaper (particularly in the case of vectors). - Value *X; - if (match(Cast, m_OneUse(m_ZExt(m_Value(X))))) { - if (Constant *TruncC = IC.getLosslessUnsignedTrunc(C, SrcTy)) { - // LogicOpc (zext X), C --> zext (LogicOpc X, C) - Value *NewOp = IC.Builder.CreateBinOp(LogicOpc, X, TruncC); - return new ZExtInst(NewOp, DestTy); - } - } - - if (match(Cast, m_OneUse(m_SExtLike(m_Value(X))))) { - if (Constant *TruncC = IC.getLosslessSignedTrunc(C, SrcTy)) { - // LogicOpc (sext X), C --> sext (LogicOpc X, C) - Value *NewOp = IC.Builder.CreateBinOp(LogicOpc, X, TruncC); - return new SExtInst(NewOp, DestTy); - } - } - - return nullptr; -} - -/// Fold {and,or,xor} (cast X), Y. -Instruction *InstCombinerImpl::foldCastedBitwiseLogic(BinaryOperator &I) { - auto LogicOpc = I.getOpcode(); - assert(I.isBitwiseLogicOp() && "Unexpected opcode for bitwise logic folding"); - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - - // fold bitwise(A >> BW - 1, zext(icmp)) (BW is the scalar bits of the - // type of A) - // -> bitwise(zext(A < 0), zext(icmp)) - // -> zext(bitwise(A < 0, icmp)) - auto FoldBitwiseICmpZeroWithICmp = [&](Value *Op0, - Value *Op1) -> Instruction * { - Value *A; - bool IsMatched = - match(Op0, - m_OneUse(m_LShr( - m_Value(A), - m_SpecificInt(Op0->getType()->getScalarSizeInBits() - 1)))) && - match(Op1, m_OneUse(m_ZExt(m_ICmp(m_Value(), m_Value())))); - - if (!IsMatched) - return nullptr; - - auto *ICmpL = - Builder.CreateICmpSLT(A, Constant::getNullValue(A->getType())); - auto *ICmpR = cast(Op1)->getOperand(0); - auto *BitwiseOp = Builder.CreateBinOp(LogicOpc, ICmpL, ICmpR); - - return new ZExtInst(BitwiseOp, Op0->getType()); - }; - - if (auto *Ret = FoldBitwiseICmpZeroWithICmp(Op0, Op1)) - return Ret; - - if (auto *Ret = FoldBitwiseICmpZeroWithICmp(Op1, Op0)) - return Ret; - - CastInst *Cast0 = dyn_cast(Op0); - if (!Cast0) - return nullptr; - - // This must be a cast from an integer or integer vector source type to allow - // transformation of the logic operation to the source type. - Type *DestTy = I.getType(); - Type *SrcTy = Cast0->getSrcTy(); - if (!SrcTy->isIntOrIntVectorTy()) - return nullptr; - - if (Instruction *Ret = foldLogicCastConstant(I, Cast0, *this)) - return Ret; - - CastInst *Cast1 = dyn_cast(Op1); - if (!Cast1) - return nullptr; - - // Both operands of the logic operation are casts. The casts must be the - // same kind for reduction. - Instruction::CastOps CastOpcode = Cast0->getOpcode(); - if (CastOpcode != Cast1->getOpcode()) - return nullptr; - - // If the source types do not match, but the casts are matching extends, we - // can still narrow the logic op. - if (SrcTy != Cast1->getSrcTy()) { - Value *X, *Y; - if (match(Cast0, m_OneUse(m_ZExtOrSExt(m_Value(X)))) && - match(Cast1, m_OneUse(m_ZExtOrSExt(m_Value(Y))))) { - // Cast the narrower source to the wider source type. - unsigned XNumBits = X->getType()->getScalarSizeInBits(); - unsigned YNumBits = Y->getType()->getScalarSizeInBits(); - if (XNumBits < YNumBits) - X = Builder.CreateCast(CastOpcode, X, Y->getType()); - else - Y = Builder.CreateCast(CastOpcode, Y, X->getType()); - // Do the logic op in the intermediate width, then widen more. - Value *NarrowLogic = Builder.CreateBinOp(LogicOpc, X, Y); - return CastInst::Create(CastOpcode, NarrowLogic, DestTy); - } - - // Give up for other cast opcodes. - return nullptr; - } - - Value *Cast0Src = Cast0->getOperand(0); - Value *Cast1Src = Cast1->getOperand(0); - - // fold logic(cast(A), cast(B)) -> cast(logic(A, B)) - if ((Cast0->hasOneUse() || Cast1->hasOneUse()) && - shouldOptimizeCast(Cast0) && shouldOptimizeCast(Cast1)) { - Value *NewOp = Builder.CreateBinOp(LogicOpc, Cast0Src, Cast1Src, - I.getName()); - return CastInst::Create(CastOpcode, NewOp, DestTy); - } - - return nullptr; -} - -static Instruction *foldAndToXor(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - assert(I.getOpcode() == Instruction::And); - Value *Op0 = I.getOperand(0); - Value *Op1 = I.getOperand(1); - Value *A, *B; - - // Operand complexity canonicalization guarantees that the 'or' is Op0. - // (A | B) & ~(A & B) --> A ^ B - // (A | B) & ~(B & A) --> A ^ B - if (match(&I, m_BinOp(m_Or(m_Value(A), m_Value(B)), - m_Not(m_c_And(m_Deferred(A), m_Deferred(B)))))) - return BinaryOperator::CreateXor(A, B); - - // (A | ~B) & (~A | B) --> ~(A ^ B) - // (A | ~B) & (B | ~A) --> ~(A ^ B) - // (~B | A) & (~A | B) --> ~(A ^ B) - // (~B | A) & (B | ~A) --> ~(A ^ B) - if (Op0->hasOneUse() || Op1->hasOneUse()) - if (match(&I, m_BinOp(m_c_Or(m_Value(A), m_Not(m_Value(B))), - m_c_Or(m_Not(m_Deferred(A)), m_Deferred(B))))) - return BinaryOperator::CreateNot(Builder.CreateXor(A, B)); - - return nullptr; -} - -static Instruction *foldOrToXor(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - assert(I.getOpcode() == Instruction::Or); - Value *Op0 = I.getOperand(0); - Value *Op1 = I.getOperand(1); - Value *A, *B; - - // Operand complexity canonicalization guarantees that the 'and' is Op0. - // (A & B) | ~(A | B) --> ~(A ^ B) - // (A & B) | ~(B | A) --> ~(A ^ B) - if (Op0->hasOneUse() || Op1->hasOneUse()) - if (match(Op0, m_And(m_Value(A), m_Value(B))) && - match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B))))) - return BinaryOperator::CreateNot(Builder.CreateXor(A, B)); - - // Operand complexity canonicalization guarantees that the 'xor' is Op0. - // (A ^ B) | ~(A | B) --> ~(A & B) - // (A ^ B) | ~(B | A) --> ~(A & B) - if (Op0->hasOneUse() || Op1->hasOneUse()) - if (match(Op0, m_Xor(m_Value(A), m_Value(B))) && - match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(A, B)); - - // (A & ~B) | (~A & B) --> A ^ B - // (A & ~B) | (B & ~A) --> A ^ B - // (~B & A) | (~A & B) --> A ^ B - // (~B & A) | (B & ~A) --> A ^ B - if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B)))) && - match(Op1, m_c_And(m_Not(m_Specific(A)), m_Specific(B)))) - return BinaryOperator::CreateXor(A, B); - - return nullptr; -} - -/// Return true if a constant shift amount is always less than the specified -/// bit-width. If not, the shift could create poison in the narrower type. -static bool canNarrowShiftAmt(Constant *C, unsigned BitWidth) { - APInt Threshold(C->getType()->getScalarSizeInBits(), BitWidth); - return match(C, m_SpecificInt_ICMP(ICmpInst::ICMP_ULT, Threshold)); -} - -/// Try to use narrower ops (sink zext ops) for an 'and' with binop operand and -/// a common zext operand: and (binop (zext X), C), (zext X). -Instruction *InstCombinerImpl::narrowMaskedBinOp(BinaryOperator &And) { - // This transform could also apply to {or, and, xor}, but there are better - // folds for those cases, so we don't expect those patterns here. AShr is not - // handled because it should always be transformed to LShr in this sequence. - // The subtract transform is different because it has a constant on the left. - // Add/mul commute the constant to RHS; sub with constant RHS becomes add. - Value *Op0 = And.getOperand(0), *Op1 = And.getOperand(1); - Constant *C; - if (!match(Op0, m_OneUse(m_Add(m_Specific(Op1), m_Constant(C)))) && - !match(Op0, m_OneUse(m_Mul(m_Specific(Op1), m_Constant(C)))) && - !match(Op0, m_OneUse(m_LShr(m_Specific(Op1), m_Constant(C)))) && - !match(Op0, m_OneUse(m_Shl(m_Specific(Op1), m_Constant(C)))) && - !match(Op0, m_OneUse(m_Sub(m_Constant(C), m_Specific(Op1))))) - return nullptr; - - Value *X; - if (!match(Op1, m_ZExt(m_Value(X))) || Op1->hasNUsesOrMore(3)) - return nullptr; - - Type *Ty = And.getType(); - if (!isa(Ty) && !shouldChangeType(Ty, X->getType())) - return nullptr; - - // If we're narrowing a shift, the shift amount must be safe (less than the - // width) in the narrower type. If the shift amount is greater, instsimplify - // usually handles that case, but we can't guarantee/assert it. - Instruction::BinaryOps Opc = cast(Op0)->getOpcode(); - if (Opc == Instruction::LShr || Opc == Instruction::Shl) - if (!canNarrowShiftAmt(C, X->getType()->getScalarSizeInBits())) - return nullptr; - - // and (sub C, (zext X)), (zext X) --> zext (and (sub C', X), X) - // and (binop (zext X), C), (zext X) --> zext (and (binop X, C'), X) - Value *NewC = ConstantExpr::getTrunc(C, X->getType()); - Value *NewBO = Opc == Instruction::Sub ? Builder.CreateBinOp(Opc, NewC, X) - : Builder.CreateBinOp(Opc, X, NewC); - return new ZExtInst(Builder.CreateAnd(NewBO, X), Ty); -} - -/// Try folding relatively complex patterns for both And and Or operations -/// with all And and Or swapped. -static Instruction *foldComplexAndOrPatterns(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - const Instruction::BinaryOps Opcode = I.getOpcode(); - assert(Opcode == Instruction::And || Opcode == Instruction::Or); - - // Flip the logic operation. - const Instruction::BinaryOps FlippedOpcode = - (Opcode == Instruction::And) ? Instruction::Or : Instruction::And; - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - Value *A, *B, *C, *X, *Y, *Dummy; - - // Match following expressions: - // (~(A | B) & C) - // (~(A & B) | C) - // Captures X = ~(A | B) or ~(A & B) - const auto matchNotOrAnd = - [Opcode, FlippedOpcode](Value *Op, auto m_A, auto m_B, auto m_C, - Value *&X, bool CountUses = false) -> bool { - if (CountUses && !Op->hasOneUse()) - return false; - - if (match(Op, m_c_BinOp(FlippedOpcode, - m_CombineAnd(m_Value(X), - m_Not(m_c_BinOp(Opcode, m_A, m_B))), - m_C))) - return !CountUses || X->hasOneUse(); - - return false; - }; - - // (~(A | B) & C) | ... --> ... - // (~(A & B) | C) & ... --> ... - // TODO: One use checks are conservative. We just need to check that a total - // number of multiple used values does not exceed reduction - // in operations. - if (matchNotOrAnd(Op0, m_Value(A), m_Value(B), m_Value(C), X)) { - // (~(A | B) & C) | (~(A | C) & B) --> (B ^ C) & ~A - // (~(A & B) | C) & (~(A & C) | B) --> ~((B ^ C) & A) - if (matchNotOrAnd(Op1, m_Specific(A), m_Specific(C), m_Specific(B), Dummy, - true)) { - Value *Xor = Builder.CreateXor(B, C); - return (Opcode == Instruction::Or) - ? BinaryOperator::CreateAnd(Xor, Builder.CreateNot(A)) - : BinaryOperator::CreateNot(Builder.CreateAnd(Xor, A)); - } - - // (~(A | B) & C) | (~(B | C) & A) --> (A ^ C) & ~B - // (~(A & B) | C) & (~(B & C) | A) --> ~((A ^ C) & B) - if (matchNotOrAnd(Op1, m_Specific(B), m_Specific(C), m_Specific(A), Dummy, - true)) { - Value *Xor = Builder.CreateXor(A, C); - return (Opcode == Instruction::Or) - ? BinaryOperator::CreateAnd(Xor, Builder.CreateNot(B)) - : BinaryOperator::CreateNot(Builder.CreateAnd(Xor, B)); - } - - // (~(A | B) & C) | ~(A | C) --> ~((B & C) | A) - // (~(A & B) | C) & ~(A & C) --> ~((B | C) & A) - if (match(Op1, m_OneUse(m_Not(m_OneUse( - m_c_BinOp(Opcode, m_Specific(A), m_Specific(C))))))) - return BinaryOperator::CreateNot(Builder.CreateBinOp( - Opcode, Builder.CreateBinOp(FlippedOpcode, B, C), A)); - - // (~(A | B) & C) | ~(B | C) --> ~((A & C) | B) - // (~(A & B) | C) & ~(B & C) --> ~((A | C) & B) - if (match(Op1, m_OneUse(m_Not(m_OneUse( - m_c_BinOp(Opcode, m_Specific(B), m_Specific(C))))))) - return BinaryOperator::CreateNot(Builder.CreateBinOp( - Opcode, Builder.CreateBinOp(FlippedOpcode, A, C), B)); - - // (~(A | B) & C) | ~(C | (A ^ B)) --> ~((A | B) & (C | (A ^ B))) - // Note, the pattern with swapped and/or is not handled because the - // result is more undefined than a source: - // (~(A & B) | C) & ~(C & (A ^ B)) --> (A ^ B ^ C) | ~(A | C) is invalid. - if (Opcode == Instruction::Or && Op0->hasOneUse() && - match(Op1, m_OneUse(m_Not(m_CombineAnd( - m_Value(Y), - m_c_BinOp(Opcode, m_Specific(C), - m_c_Xor(m_Specific(A), m_Specific(B)))))))) { - // X = ~(A | B) - // Y = (C | (A ^ B) - Value *Or = cast(X)->getOperand(0); - return BinaryOperator::CreateNot(Builder.CreateAnd(Or, Y)); - } - } - - // (~A & B & C) | ... --> ... - // (~A | B | C) | ... --> ... - // TODO: One use checks are conservative. We just need to check that a total - // number of multiple used values does not exceed reduction - // in operations. - if (match(Op0, - m_OneUse(m_c_BinOp(FlippedOpcode, - m_BinOp(FlippedOpcode, m_Value(B), m_Value(C)), - m_CombineAnd(m_Value(X), m_Not(m_Value(A)))))) || - match(Op0, m_OneUse(m_c_BinOp( - FlippedOpcode, - m_c_BinOp(FlippedOpcode, m_Value(C), - m_CombineAnd(m_Value(X), m_Not(m_Value(A)))), - m_Value(B))))) { - // X = ~A - // (~A & B & C) | ~(A | B | C) --> ~(A | (B ^ C)) - // (~A | B | C) & ~(A & B & C) --> (~A | (B ^ C)) - if (match(Op1, m_OneUse(m_Not(m_c_BinOp( - Opcode, m_c_BinOp(Opcode, m_Specific(A), m_Specific(B)), - m_Specific(C))))) || - match(Op1, m_OneUse(m_Not(m_c_BinOp( - Opcode, m_c_BinOp(Opcode, m_Specific(B), m_Specific(C)), - m_Specific(A))))) || - match(Op1, m_OneUse(m_Not(m_c_BinOp( - Opcode, m_c_BinOp(Opcode, m_Specific(A), m_Specific(C)), - m_Specific(B)))))) { - Value *Xor = Builder.CreateXor(B, C); - return (Opcode == Instruction::Or) - ? BinaryOperator::CreateNot(Builder.CreateOr(Xor, A)) - : BinaryOperator::CreateOr(Xor, X); - } - - // (~A & B & C) | ~(A | B) --> (C | ~B) & ~A - // (~A | B | C) & ~(A & B) --> (C & ~B) | ~A - if (match(Op1, m_OneUse(m_Not(m_OneUse( - m_c_BinOp(Opcode, m_Specific(A), m_Specific(B))))))) - return BinaryOperator::Create( - FlippedOpcode, Builder.CreateBinOp(Opcode, C, Builder.CreateNot(B)), - X); - - // (~A & B & C) | ~(A | C) --> (B | ~C) & ~A - // (~A | B | C) & ~(A & C) --> (B & ~C) | ~A - if (match(Op1, m_OneUse(m_Not(m_OneUse( - m_c_BinOp(Opcode, m_Specific(A), m_Specific(C))))))) - return BinaryOperator::Create( - FlippedOpcode, Builder.CreateBinOp(Opcode, B, Builder.CreateNot(C)), - X); - } - - return nullptr; -} - -/// Try to reassociate a pair of binops so that values with one use only are -/// part of the same instruction. This may enable folds that are limited with -/// multi-use restrictions and makes it more likely to match other patterns that -/// are looking for a common operand. -static Instruction *reassociateForUses(BinaryOperator &BO, - InstCombinerImpl::BuilderTy &Builder) { - Instruction::BinaryOps Opcode = BO.getOpcode(); - Value *X, *Y, *Z; - if (match(&BO, - m_c_BinOp(Opcode, m_OneUse(m_BinOp(Opcode, m_Value(X), m_Value(Y))), - m_OneUse(m_Value(Z))))) { - if (!isa(X) && !isa(Y) && !isa(Z)) { - // (X op Y) op Z --> (Y op Z) op X - if (!X->hasOneUse()) { - Value *YZ = Builder.CreateBinOp(Opcode, Y, Z); - return BinaryOperator::Create(Opcode, YZ, X); - } - // (X op Y) op Z --> (X op Z) op Y - if (!Y->hasOneUse()) { - Value *XZ = Builder.CreateBinOp(Opcode, X, Z); - return BinaryOperator::Create(Opcode, XZ, Y); - } - } - } - - return nullptr; -} - -// Match -// (X + C2) | C -// (X + C2) ^ C -// (X + C2) & C -// and convert to do the bitwise logic first: -// (X | C) + C2 -// (X ^ C) + C2 -// (X & C) + C2 -// iff bits affected by logic op are lower than last bit affected by math op -static Instruction *canonicalizeLogicFirst(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - Type *Ty = I.getType(); - Instruction::BinaryOps OpC = I.getOpcode(); - Value *Op0 = I.getOperand(0); - Value *Op1 = I.getOperand(1); - Value *X; - const APInt *C, *C2; - - if (!(match(Op0, m_OneUse(m_Add(m_Value(X), m_APInt(C2)))) && - match(Op1, m_APInt(C)))) - return nullptr; - - unsigned Width = Ty->getScalarSizeInBits(); - unsigned LastOneMath = Width - C2->countr_zero(); - - switch (OpC) { - case Instruction::And: - if (C->countl_one() < LastOneMath) - return nullptr; - break; - case Instruction::Xor: - case Instruction::Or: - if (C->countl_zero() < LastOneMath) - return nullptr; - break; - default: - llvm_unreachable("Unexpected BinaryOp!"); - } - - Value *NewBinOp = Builder.CreateBinOp(OpC, X, ConstantInt::get(Ty, *C)); - return BinaryOperator::CreateWithCopiedFlags(Instruction::Add, NewBinOp, - ConstantInt::get(Ty, *C2), Op0); -} - -// binop(shift(ShiftedC1, ShAmt), shift(ShiftedC2, add(ShAmt, AddC))) -> -// shift(binop(ShiftedC1, shift(ShiftedC2, AddC)), ShAmt) -// where both shifts are the same and AddC is a valid shift amount. -Instruction *InstCombinerImpl::foldBinOpOfDisplacedShifts(BinaryOperator &I) { - assert((I.isBitwiseLogicOp() || I.getOpcode() == Instruction::Add) && - "Unexpected opcode"); - - Value *ShAmt; - Constant *ShiftedC1, *ShiftedC2, *AddC; - Type *Ty = I.getType(); - unsigned BitWidth = Ty->getScalarSizeInBits(); - if (!match(&I, m_c_BinOp(m_Shift(m_ImmConstant(ShiftedC1), m_Value(ShAmt)), - m_Shift(m_ImmConstant(ShiftedC2), - m_AddLike(m_Deferred(ShAmt), - m_ImmConstant(AddC)))))) - return nullptr; - - // Make sure the add constant is a valid shift amount. - if (!match(AddC, - m_SpecificInt_ICMP(ICmpInst::ICMP_ULT, APInt(BitWidth, BitWidth)))) - return nullptr; - - // Avoid constant expressions. - auto *Op0Inst = dyn_cast(I.getOperand(0)); - auto *Op1Inst = dyn_cast(I.getOperand(1)); - if (!Op0Inst || !Op1Inst) - return nullptr; - - // Both shifts must be the same. - Instruction::BinaryOps ShiftOp = - static_cast(Op0Inst->getOpcode()); - if (ShiftOp != Op1Inst->getOpcode()) - return nullptr; - - // For adds, only left shifts are supported. - if (I.getOpcode() == Instruction::Add && ShiftOp != Instruction::Shl) - return nullptr; - - Value *NewC = Builder.CreateBinOp( - I.getOpcode(), ShiftedC1, Builder.CreateBinOp(ShiftOp, ShiftedC2, AddC)); - return BinaryOperator::Create(ShiftOp, NewC, ShAmt); -} - -// Fold and/or/xor with two equal intrinsic IDs: -// bitwise(fshl (A, B, ShAmt), fshl(C, D, ShAmt)) -// -> fshl(bitwise(A, C), bitwise(B, D), ShAmt) -// bitwise(fshr (A, B, ShAmt), fshr(C, D, ShAmt)) -// -> fshr(bitwise(A, C), bitwise(B, D), ShAmt) -// bitwise(bswap(A), bswap(B)) -> bswap(bitwise(A, B)) -// bitwise(bswap(A), C) -> bswap(bitwise(A, bswap(C))) -// bitwise(bitreverse(A), bitreverse(B)) -> bitreverse(bitwise(A, B)) -// bitwise(bitreverse(A), C) -> bitreverse(bitwise(A, bitreverse(C))) -static Instruction * -foldBitwiseLogicWithIntrinsics(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - assert(I.isBitwiseLogicOp() && "Should and/or/xor"); - if (!I.getOperand(0)->hasOneUse()) - return nullptr; - IntrinsicInst *X = dyn_cast(I.getOperand(0)); - if (!X) - return nullptr; - - IntrinsicInst *Y = dyn_cast(I.getOperand(1)); - if (Y && (!Y->hasOneUse() || X->getIntrinsicID() != Y->getIntrinsicID())) - return nullptr; - - Intrinsic::ID IID = X->getIntrinsicID(); - const APInt *RHSC; - // Try to match constant RHS. - if (!Y && (!(IID == Intrinsic::bswap || IID == Intrinsic::bitreverse) || - !match(I.getOperand(1), m_APInt(RHSC)))) - return nullptr; - - switch (IID) { - case Intrinsic::fshl: - case Intrinsic::fshr: { - if (X->getOperand(2) != Y->getOperand(2)) - return nullptr; - Value *NewOp0 = - Builder.CreateBinOp(I.getOpcode(), X->getOperand(0), Y->getOperand(0)); - Value *NewOp1 = - Builder.CreateBinOp(I.getOpcode(), X->getOperand(1), Y->getOperand(1)); - Function *F = - Intrinsic::getOrInsertDeclaration(I.getModule(), IID, I.getType()); - return CallInst::Create(F, {NewOp0, NewOp1, X->getOperand(2)}); - } - case Intrinsic::bswap: - case Intrinsic::bitreverse: { - Value *NewOp0 = Builder.CreateBinOp( - I.getOpcode(), X->getOperand(0), - Y ? Y->getOperand(0) - : ConstantInt::get(I.getType(), IID == Intrinsic::bswap - ? RHSC->byteSwap() - : RHSC->reverseBits())); - Function *F = - Intrinsic::getOrInsertDeclaration(I.getModule(), IID, I.getType()); - return CallInst::Create(F, {NewOp0}); - } - default: - return nullptr; - } -} - -// Try to simplify V by replacing occurrences of Op with RepOp, but only look -// through bitwise operations. In particular, for X | Y we try to replace Y with -// 0 inside X and for X & Y we try to replace Y with -1 inside X. -// Return the simplified result of X if successful, and nullptr otherwise. -// If SimplifyOnly is true, no new instructions will be created. -static Value *simplifyAndOrWithOpReplaced(Value *V, Value *Op, Value *RepOp, - bool SimplifyOnly, - InstCombinerImpl &IC, - unsigned Depth = 0) { - if (Op == RepOp) - return nullptr; - - if (V == Op) - return RepOp; - - auto *I = dyn_cast(V); - if (!I || !I->isBitwiseLogicOp() || Depth >= 3) - return nullptr; - - if (!I->hasOneUse()) - SimplifyOnly = true; - - Value *NewOp0 = simplifyAndOrWithOpReplaced(I->getOperand(0), Op, RepOp, - SimplifyOnly, IC, Depth + 1); - Value *NewOp1 = simplifyAndOrWithOpReplaced(I->getOperand(1), Op, RepOp, - SimplifyOnly, IC, Depth + 1); - if (!NewOp0 && !NewOp1) - return nullptr; - - if (!NewOp0) - NewOp0 = I->getOperand(0); - if (!NewOp1) - NewOp1 = I->getOperand(1); - - if (Value *Res = simplifyBinOp(I->getOpcode(), NewOp0, NewOp1, - IC.getSimplifyQuery().getWithInstruction(I))) - return Res; - - if (SimplifyOnly) - return nullptr; - return IC.Builder.CreateBinOp(I->getOpcode(), NewOp0, NewOp1); -} - -/// Reassociate and/or expressions to see if we can fold the inner and/or ops. -/// TODO: Make this recursive; it's a little tricky because an arbitrary -/// number of and/or instructions might have to be created. -Value *InstCombinerImpl::reassociateBooleanAndOr(Value *LHS, Value *X, Value *Y, - Instruction &I, bool IsAnd, - bool RHSIsLogical) { - Instruction::BinaryOps Opcode = IsAnd ? Instruction::And : Instruction::Or; - // LHS bop (X lop Y) --> (LHS bop X) lop Y - // LHS bop (X bop Y) --> (LHS bop X) bop Y - if (Value *Res = foldBooleanAndOr(LHS, X, I, IsAnd, /*IsLogical=*/false)) - return RHSIsLogical ? Builder.CreateLogicalOp(Opcode, Res, Y) - : Builder.CreateBinOp(Opcode, Res, Y); - // LHS bop (X bop Y) --> X bop (LHS bop Y) - // LHS bop (X lop Y) --> X lop (LHS bop Y) - if (Value *Res = foldBooleanAndOr(LHS, Y, I, IsAnd, /*IsLogical=*/false)) - return RHSIsLogical ? Builder.CreateLogicalOp(Opcode, X, Res) - : Builder.CreateBinOp(Opcode, X, Res); - return nullptr; -} - -// FIXME: We use commutative matchers (m_c_*) for some, but not all, matches -// here. We should standardize that construct where it is needed or choose some -// other way to ensure that commutated variants of patterns are not missed. -Instruction *InstCombinerImpl::visitAnd(BinaryOperator &I) { - Type *Ty = I.getType(); - - if (Value *V = simplifyAndInst(I.getOperand(0), I.getOperand(1), - SQ.getWithInstruction(&I))) - return replaceInstUsesWith(I, V); - - if (SimplifyAssociativeOrCommutative(I)) - return &I; - - if (Instruction *X = foldVectorBinop(I)) - return X; - - if (Instruction *Phi = foldBinopWithPhiOperands(I)) - return Phi; - - // See if we can simplify any instructions used by the instruction whose sole - // purpose is to compute bits we don't care about. - if (SimplifyDemandedInstructionBits(I)) - return &I; - - // Do this before using distributive laws to catch simple and/or/not patterns. - if (Instruction *Xor = foldAndToXor(I, Builder)) - return Xor; - - if (Instruction *X = foldComplexAndOrPatterns(I, Builder)) - return X; - - // (A|B)&(A|C) -> A|(B&C) etc - if (Value *V = foldUsingDistributiveLaws(I)) - return replaceInstUsesWith(I, V); - - if (Instruction *R = foldBinOpShiftWithShift(I)) - return R; - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - - Value *X, *Y; - const APInt *C; - if ((match(Op0, m_OneUse(m_LogicalShift(m_One(), m_Value(X)))) || - (match(Op0, m_OneUse(m_Shl(m_APInt(C), m_Value(X)))) && (*C)[0])) && - match(Op1, m_One())) { - // (1 >> X) & 1 --> zext(X == 0) - // (C << X) & 1 --> zext(X == 0), when C is odd - Value *IsZero = Builder.CreateICmpEQ(X, ConstantInt::get(Ty, 0)); - return new ZExtInst(IsZero, Ty); - } - - // (-(X & 1)) & Y --> (X & 1) == 0 ? 0 : Y - Value *Neg; - if (match(&I, - m_c_And(m_CombineAnd(m_Value(Neg), - m_OneUse(m_Neg(m_And(m_Value(), m_One())))), - m_Value(Y)))) { - Value *Cmp = Builder.CreateIsNull(Neg); - return SelectInst::Create(Cmp, ConstantInt::getNullValue(Ty), Y); - } - - // Canonicalize: - // (X +/- Y) & Y --> ~X & Y when Y is a power of 2. - if (match(&I, m_c_And(m_Value(Y), m_OneUse(m_CombineOr( - m_c_Add(m_Value(X), m_Deferred(Y)), - m_Sub(m_Value(X), m_Deferred(Y)))))) && - isKnownToBeAPowerOfTwo(Y, /*OrZero*/ true, /*Depth*/ 0, &I)) - return BinaryOperator::CreateAnd(Builder.CreateNot(X), Y); - - if (match(Op1, m_APInt(C))) { - const APInt *XorC; - if (match(Op0, m_OneUse(m_Xor(m_Value(X), m_APInt(XorC))))) { - // (X ^ C1) & C2 --> (X & C2) ^ (C1&C2) - Constant *NewC = ConstantInt::get(Ty, *C & *XorC); - Value *And = Builder.CreateAnd(X, Op1); - And->takeName(Op0); - return BinaryOperator::CreateXor(And, NewC); - } - - const APInt *OrC; - if (match(Op0, m_OneUse(m_Or(m_Value(X), m_APInt(OrC))))) { - // (X | C1) & C2 --> (X & C2^(C1&C2)) | (C1&C2) - // NOTE: This reduces the number of bits set in the & mask, which - // can expose opportunities for store narrowing for scalars. - // NOTE: SimplifyDemandedBits should have already removed bits from C1 - // that aren't set in C2. Meaning we can replace (C1&C2) with C1 in - // above, but this feels safer. - APInt Together = *C & *OrC; - Value *And = Builder.CreateAnd(X, ConstantInt::get(Ty, Together ^ *C)); - And->takeName(Op0); - return BinaryOperator::CreateOr(And, ConstantInt::get(Ty, Together)); - } - - unsigned Width = Ty->getScalarSizeInBits(); - const APInt *ShiftC; - if (match(Op0, m_OneUse(m_SExt(m_AShr(m_Value(X), m_APInt(ShiftC))))) && - ShiftC->ult(Width)) { - if (*C == APInt::getLowBitsSet(Width, Width - ShiftC->getZExtValue())) { - // We are clearing high bits that were potentially set by sext+ashr: - // and (sext (ashr X, ShiftC)), C --> lshr (sext X), ShiftC - Value *Sext = Builder.CreateSExt(X, Ty); - Constant *ShAmtC = ConstantInt::get(Ty, ShiftC->zext(Width)); - return BinaryOperator::CreateLShr(Sext, ShAmtC); - } - } - - // If this 'and' clears the sign-bits added by ashr, replace with lshr: - // and (ashr X, ShiftC), C --> lshr X, ShiftC - if (match(Op0, m_AShr(m_Value(X), m_APInt(ShiftC))) && ShiftC->ult(Width) && - C->isMask(Width - ShiftC->getZExtValue())) - return BinaryOperator::CreateLShr(X, ConstantInt::get(Ty, *ShiftC)); - - const APInt *AddC; - if (match(Op0, m_Add(m_Value(X), m_APInt(AddC)))) { - // If we are masking the result of the add down to exactly one bit and - // the constant we are adding has no bits set below that bit, then the - // add is flipping a single bit. Example: - // (X + 4) & 4 --> (X & 4) ^ 4 - if (Op0->hasOneUse() && C->isPowerOf2() && (*AddC & (*C - 1)) == 0) { - assert((*C & *AddC) != 0 && "Expected common bit"); - Value *NewAnd = Builder.CreateAnd(X, Op1); - return BinaryOperator::CreateXor(NewAnd, Op1); - } - } - - // ((C1 OP zext(X)) & C2) -> zext((C1 OP X) & C2) if C2 fits in the - // bitwidth of X and OP behaves well when given trunc(C1) and X. - auto isNarrowableBinOpcode = [](BinaryOperator *B) { - switch (B->getOpcode()) { - case Instruction::Xor: - case Instruction::Or: - case Instruction::Mul: - case Instruction::Add: - case Instruction::Sub: - return true; - default: - return false; - } - }; - BinaryOperator *BO; - if (match(Op0, m_OneUse(m_BinOp(BO))) && isNarrowableBinOpcode(BO)) { - Instruction::BinaryOps BOpcode = BO->getOpcode(); - Value *X; - const APInt *C1; - // TODO: The one-use restrictions could be relaxed a little if the AND - // is going to be removed. - // Try to narrow the 'and' and a binop with constant operand: - // and (bo (zext X), C1), C --> zext (and (bo X, TruncC1), TruncC) - if (match(BO, m_c_BinOp(m_OneUse(m_ZExt(m_Value(X))), m_APInt(C1))) && - C->isIntN(X->getType()->getScalarSizeInBits())) { - unsigned XWidth = X->getType()->getScalarSizeInBits(); - Constant *TruncC1 = ConstantInt::get(X->getType(), C1->trunc(XWidth)); - Value *BinOp = isa(BO->getOperand(0)) - ? Builder.CreateBinOp(BOpcode, X, TruncC1) - : Builder.CreateBinOp(BOpcode, TruncC1, X); - Constant *TruncC = ConstantInt::get(X->getType(), C->trunc(XWidth)); - Value *And = Builder.CreateAnd(BinOp, TruncC); - return new ZExtInst(And, Ty); - } - - // Similar to above: if the mask matches the zext input width, then the - // 'and' can be eliminated, so we can truncate the other variable op: - // and (bo (zext X), Y), C --> zext (bo X, (trunc Y)) - if (isa(BO->getOperand(0)) && - match(BO->getOperand(0), m_OneUse(m_ZExt(m_Value(X)))) && - C->isMask(X->getType()->getScalarSizeInBits())) { - Y = BO->getOperand(1); - Value *TrY = Builder.CreateTrunc(Y, X->getType(), Y->getName() + ".tr"); - Value *NewBO = - Builder.CreateBinOp(BOpcode, X, TrY, BO->getName() + ".narrow"); - return new ZExtInst(NewBO, Ty); - } - // and (bo Y, (zext X)), C --> zext (bo (trunc Y), X) - if (isa(BO->getOperand(1)) && - match(BO->getOperand(1), m_OneUse(m_ZExt(m_Value(X)))) && - C->isMask(X->getType()->getScalarSizeInBits())) { - Y = BO->getOperand(0); - Value *TrY = Builder.CreateTrunc(Y, X->getType(), Y->getName() + ".tr"); - Value *NewBO = - Builder.CreateBinOp(BOpcode, TrY, X, BO->getName() + ".narrow"); - return new ZExtInst(NewBO, Ty); - } - } - - // This is intentionally placed after the narrowing transforms for - // efficiency (transform directly to the narrow logic op if possible). - // If the mask is only needed on one incoming arm, push the 'and' op up. - if (match(Op0, m_OneUse(m_Xor(m_Value(X), m_Value(Y)))) || - match(Op0, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) { - APInt NotAndMask(~(*C)); - BinaryOperator::BinaryOps BinOp = cast(Op0)->getOpcode(); - if (MaskedValueIsZero(X, NotAndMask, 0, &I)) { - // Not masking anything out for the LHS, move mask to RHS. - // and ({x}or X, Y), C --> {x}or X, (and Y, C) - Value *NewRHS = Builder.CreateAnd(Y, Op1, Y->getName() + ".masked"); - return BinaryOperator::Create(BinOp, X, NewRHS); - } - if (!isa(Y) && MaskedValueIsZero(Y, NotAndMask, 0, &I)) { - // Not masking anything out for the RHS, move mask to LHS. - // and ({x}or X, Y), C --> {x}or (and X, C), Y - Value *NewLHS = Builder.CreateAnd(X, Op1, X->getName() + ".masked"); - return BinaryOperator::Create(BinOp, NewLHS, Y); - } - } - - // When the mask is a power-of-2 constant and op0 is a shifted-power-of-2 - // constant, test if the shift amount equals the offset bit index: - // (ShiftC << X) & C --> X == (log2(C) - log2(ShiftC)) ? C : 0 - // (ShiftC >> X) & C --> X == (log2(ShiftC) - log2(C)) ? C : 0 - if (C->isPowerOf2() && - match(Op0, m_OneUse(m_LogicalShift(m_Power2(ShiftC), m_Value(X))))) { - int Log2ShiftC = ShiftC->exactLogBase2(); - int Log2C = C->exactLogBase2(); - bool IsShiftLeft = - cast(Op0)->getOpcode() == Instruction::Shl; - int BitNum = IsShiftLeft ? Log2C - Log2ShiftC : Log2ShiftC - Log2C; - assert(BitNum >= 0 && "Expected demanded bits to handle impossible mask"); - Value *Cmp = Builder.CreateICmpEQ(X, ConstantInt::get(Ty, BitNum)); - return SelectInst::Create(Cmp, ConstantInt::get(Ty, *C), - ConstantInt::getNullValue(Ty)); - } - - Constant *C1, *C2; - const APInt *C3 = C; - Value *X; - if (C3->isPowerOf2()) { - Constant *Log2C3 = ConstantInt::get(Ty, C3->countr_zero()); - if (match(Op0, m_OneUse(m_LShr(m_Shl(m_ImmConstant(C1), m_Value(X)), - m_ImmConstant(C2)))) && - match(C1, m_Power2())) { - Constant *Log2C1 = ConstantExpr::getExactLogBase2(C1); - Constant *LshrC = ConstantExpr::getAdd(C2, Log2C3); - KnownBits KnownLShrc = computeKnownBits(LshrC, 0, nullptr); - if (KnownLShrc.getMaxValue().ult(Width)) { - // iff C1,C3 is pow2 and C2 + cttz(C3) < BitWidth: - // ((C1 << X) >> C2) & C3 -> X == (cttz(C3)+C2-cttz(C1)) ? C3 : 0 - Constant *CmpC = ConstantExpr::getSub(LshrC, Log2C1); - Value *Cmp = Builder.CreateICmpEQ(X, CmpC); - return SelectInst::Create(Cmp, ConstantInt::get(Ty, *C3), - ConstantInt::getNullValue(Ty)); - } - } - - if (match(Op0, m_OneUse(m_Shl(m_LShr(m_ImmConstant(C1), m_Value(X)), - m_ImmConstant(C2)))) && - match(C1, m_Power2())) { - Constant *Log2C1 = ConstantExpr::getExactLogBase2(C1); - Constant *Cmp = - ConstantFoldCompareInstOperands(ICmpInst::ICMP_ULT, Log2C3, C2, DL); - if (Cmp && Cmp->isZeroValue()) { - // iff C1,C3 is pow2 and Log2(C3) >= C2: - // ((C1 >> X) << C2) & C3 -> X == (cttz(C1)+C2-cttz(C3)) ? C3 : 0 - Constant *ShlC = ConstantExpr::getAdd(C2, Log2C1); - Constant *CmpC = ConstantExpr::getSub(ShlC, Log2C3); - Value *Cmp = Builder.CreateICmpEQ(X, CmpC); - return SelectInst::Create(Cmp, ConstantInt::get(Ty, *C3), - ConstantInt::getNullValue(Ty)); - } - } - } - } - - // If we are clearing the sign bit of a floating-point value, convert this to - // fabs, then cast back to integer. - // - // This is a generous interpretation for noimplicitfloat, this is not a true - // floating-point operation. - // - // Assumes any IEEE-represented type has the sign bit in the high bit. - // TODO: Unify with APInt matcher. This version allows undef unlike m_APInt - Value *CastOp; - if (match(Op0, m_ElementWiseBitCast(m_Value(CastOp))) && - match(Op1, m_MaxSignedValue()) && - !Builder.GetInsertBlock()->getParent()->hasFnAttribute( - Attribute::NoImplicitFloat)) { - Type *EltTy = CastOp->getType()->getScalarType(); - if (EltTy->isFloatingPointTy() && EltTy->isIEEE()) { - Value *FAbs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, CastOp); - return new BitCastInst(FAbs, I.getType()); - } - } - - // and(shl(zext(X), Y), SignMask) -> and(sext(X), SignMask) - // where Y is a valid shift amount. - if (match(&I, m_And(m_OneUse(m_Shl(m_ZExt(m_Value(X)), m_Value(Y))), - m_SignMask())) && - match(Y, m_SpecificInt_ICMP( - ICmpInst::Predicate::ICMP_EQ, - APInt(Ty->getScalarSizeInBits(), - Ty->getScalarSizeInBits() - - X->getType()->getScalarSizeInBits())))) { - auto *SExt = Builder.CreateSExt(X, Ty, X->getName() + ".signext"); - return BinaryOperator::CreateAnd(SExt, Op1); - } - - if (Instruction *Z = narrowMaskedBinOp(I)) - return Z; - - if (I.getType()->isIntOrIntVectorTy(1)) { - if (auto *SI0 = dyn_cast(Op0)) { - if (auto *R = - foldAndOrOfSelectUsingImpliedCond(Op1, *SI0, /* IsAnd */ true)) - return R; - } - if (auto *SI1 = dyn_cast(Op1)) { - if (auto *R = - foldAndOrOfSelectUsingImpliedCond(Op0, *SI1, /* IsAnd */ true)) - return R; - } - } - - if (Instruction *FoldedLogic = foldBinOpIntoSelectOrPhi(I)) - return FoldedLogic; - - if (Instruction *DeMorgan = matchDeMorgansLaws(I, *this)) - return DeMorgan; - - { - Value *A, *B, *C; - // A & ~(A ^ B) --> A & B - if (match(Op1, m_Not(m_c_Xor(m_Specific(Op0), m_Value(B))))) - return BinaryOperator::CreateAnd(Op0, B); - // ~(A ^ B) & A --> A & B - if (match(Op0, m_Not(m_c_Xor(m_Specific(Op1), m_Value(B))))) - return BinaryOperator::CreateAnd(Op1, B); - - // (A ^ B) & ((B ^ C) ^ A) -> (A ^ B) & ~C - if (match(Op0, m_Xor(m_Value(A), m_Value(B))) && - match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A)))) { - Value *NotC = Op1->hasOneUse() - ? Builder.CreateNot(C) - : getFreelyInverted(C, C->hasOneUse(), &Builder); - if (NotC != nullptr) - return BinaryOperator::CreateAnd(Op0, NotC); - } - - // ((A ^ C) ^ B) & (B ^ A) -> (B ^ A) & ~C - if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))) && - match(Op1, m_Xor(m_Specific(B), m_Specific(A)))) { - Value *NotC = Op0->hasOneUse() - ? Builder.CreateNot(C) - : getFreelyInverted(C, C->hasOneUse(), &Builder); - if (NotC != nullptr) - return BinaryOperator::CreateAnd(Op1, Builder.CreateNot(C)); - } - - // (A | B) & (~A ^ B) -> A & B - // (A | B) & (B ^ ~A) -> A & B - // (B | A) & (~A ^ B) -> A & B - // (B | A) & (B ^ ~A) -> A & B - if (match(Op1, m_c_Xor(m_Not(m_Value(A)), m_Value(B))) && - match(Op0, m_c_Or(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateAnd(A, B); - - // (~A ^ B) & (A | B) -> A & B - // (~A ^ B) & (B | A) -> A & B - // (B ^ ~A) & (A | B) -> A & B - // (B ^ ~A) & (B | A) -> A & B - if (match(Op0, m_c_Xor(m_Not(m_Value(A)), m_Value(B))) && - match(Op1, m_c_Or(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateAnd(A, B); - - // (~A | B) & (A ^ B) -> ~A & B - // (~A | B) & (B ^ A) -> ~A & B - // (B | ~A) & (A ^ B) -> ~A & B - // (B | ~A) & (B ^ A) -> ~A & B - if (match(Op0, m_c_Or(m_Not(m_Value(A)), m_Value(B))) && - match(Op1, m_c_Xor(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateAnd(Builder.CreateNot(A), B); - - // (A ^ B) & (~A | B) -> ~A & B - // (B ^ A) & (~A | B) -> ~A & B - // (A ^ B) & (B | ~A) -> ~A & B - // (B ^ A) & (B | ~A) -> ~A & B - if (match(Op1, m_c_Or(m_Not(m_Value(A)), m_Value(B))) && - match(Op0, m_c_Xor(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateAnd(Builder.CreateNot(A), B); - } - - if (Value *Res = - foldBooleanAndOr(Op0, Op1, I, /*IsAnd=*/true, /*IsLogical=*/false)) - return replaceInstUsesWith(I, Res); - - if (match(Op1, m_OneUse(m_LogicalAnd(m_Value(X), m_Value(Y))))) { - bool IsLogical = isa(Op1); - if (auto *V = reassociateBooleanAndOr(Op0, X, Y, I, /*IsAnd=*/true, - /*RHSIsLogical=*/IsLogical)) - return replaceInstUsesWith(I, V); - } - if (match(Op0, m_OneUse(m_LogicalAnd(m_Value(X), m_Value(Y))))) { - bool IsLogical = isa(Op0); - if (auto *V = reassociateBooleanAndOr(Op1, X, Y, I, /*IsAnd=*/true, - /*RHSIsLogical=*/IsLogical)) - return replaceInstUsesWith(I, V); - } - - if (Instruction *FoldedFCmps = reassociateFCmps(I, Builder)) - return FoldedFCmps; - - if (Instruction *CastedAnd = foldCastedBitwiseLogic(I)) - return CastedAnd; - - if (Instruction *Sel = foldBinopOfSextBoolToSelect(I)) - return Sel; - - // and(sext(A), B) / and(B, sext(A)) --> A ? B : 0, where A is i1 or . - // TODO: Move this into foldBinopOfSextBoolToSelect as a more generalized fold - // with binop identity constant. But creating a select with non-constant - // arm may not be reversible due to poison semantics. Is that a good - // canonicalization? - Value *A, *B; - if (match(&I, m_c_And(m_SExt(m_Value(A)), m_Value(B))) && - A->getType()->isIntOrIntVectorTy(1)) - return SelectInst::Create(A, B, Constant::getNullValue(Ty)); - - // Similarly, a 'not' of the bool translates to a swap of the select arms: - // ~sext(A) & B / B & ~sext(A) --> A ? 0 : B - if (match(&I, m_c_And(m_Not(m_SExt(m_Value(A))), m_Value(B))) && - A->getType()->isIntOrIntVectorTy(1)) - return SelectInst::Create(A, Constant::getNullValue(Ty), B); - - // and(zext(A), B) -> A ? (B & 1) : 0 - if (match(&I, m_c_And(m_OneUse(m_ZExt(m_Value(A))), m_Value(B))) && - A->getType()->isIntOrIntVectorTy(1)) - return SelectInst::Create(A, Builder.CreateAnd(B, ConstantInt::get(Ty, 1)), - Constant::getNullValue(Ty)); - - // (-1 + A) & B --> A ? 0 : B where A is 0/1. - if (match(&I, m_c_And(m_OneUse(m_Add(m_ZExtOrSelf(m_Value(A)), m_AllOnes())), - m_Value(B)))) { - if (A->getType()->isIntOrIntVectorTy(1)) - return SelectInst::Create(A, Constant::getNullValue(Ty), B); - if (computeKnownBits(A, /* Depth */ 0, &I).countMaxActiveBits() <= 1) { - return SelectInst::Create( - Builder.CreateICmpEQ(A, Constant::getNullValue(A->getType())), B, - Constant::getNullValue(Ty)); - } - } - - // (iN X s>> (N-1)) & Y --> (X s< 0) ? Y : 0 -- with optional sext - if (match(&I, m_c_And(m_OneUse(m_SExtOrSelf( - m_AShr(m_Value(X), m_APIntAllowPoison(C)))), - m_Value(Y))) && - *C == X->getType()->getScalarSizeInBits() - 1) { - Value *IsNeg = Builder.CreateIsNeg(X, "isneg"); - return SelectInst::Create(IsNeg, Y, ConstantInt::getNullValue(Ty)); - } - // If there's a 'not' of the shifted value, swap the select operands: - // ~(iN X s>> (N-1)) & Y --> (X s< 0) ? 0 : Y -- with optional sext - if (match(&I, m_c_And(m_OneUse(m_SExtOrSelf( - m_Not(m_AShr(m_Value(X), m_APIntAllowPoison(C))))), - m_Value(Y))) && - *C == X->getType()->getScalarSizeInBits() - 1) { - Value *IsNeg = Builder.CreateIsNeg(X, "isneg"); - return SelectInst::Create(IsNeg, ConstantInt::getNullValue(Ty), Y); - } - - // (~x) & y --> ~(x | (~y)) iff that gets rid of inversions - if (sinkNotIntoOtherHandOfLogicalOp(I)) - return &I; - - // An and recurrence w/loop invariant step is equivelent to (and start, step) - PHINode *PN = nullptr; - Value *Start = nullptr, *Step = nullptr; - if (matchSimpleRecurrence(&I, PN, Start, Step) && DT.dominates(Step, PN)) - return replaceInstUsesWith(I, Builder.CreateAnd(Start, Step)); - - if (Instruction *R = reassociateForUses(I, Builder)) - return R; - - if (Instruction *Canonicalized = canonicalizeLogicFirst(I, Builder)) - return Canonicalized; - - if (Instruction *Folded = foldLogicOfIsFPClass(I, Op0, Op1)) - return Folded; - - if (Instruction *Res = foldBinOpOfDisplacedShifts(I)) - return Res; - - if (Instruction *Res = foldBitwiseLogicWithIntrinsics(I, Builder)) - return Res; - - if (Value *V = - simplifyAndOrWithOpReplaced(Op0, Op1, Constant::getAllOnesValue(Ty), - /*SimplifyOnly*/ false, *this)) - return BinaryOperator::CreateAnd(V, Op1); - if (Value *V = - simplifyAndOrWithOpReplaced(Op1, Op0, Constant::getAllOnesValue(Ty), - /*SimplifyOnly*/ false, *this)) - return BinaryOperator::CreateAnd(Op0, V); - - return nullptr; -} - -Instruction *InstCombinerImpl::matchBSwapOrBitReverse(Instruction &I, - bool MatchBSwaps, - bool MatchBitReversals) { - SmallVector Insts; - if (!recognizeBSwapOrBitReverseIdiom(&I, MatchBSwaps, MatchBitReversals, - Insts)) - return nullptr; - Instruction *LastInst = Insts.pop_back_val(); - LastInst->removeFromParent(); - - for (auto *Inst : Insts) { - Inst->setDebugLoc(I.getDebugLoc()); - Worklist.push(Inst); - } - return LastInst; -} - -std::optional>> -InstCombinerImpl::convertOrOfShiftsToFunnelShift(Instruction &Or) { - // TODO: Can we reduce the code duplication between this and the related - // rotate matching code under visitSelect and visitTrunc? - assert(Or.getOpcode() == BinaryOperator::Or && "Expecting or instruction"); - - unsigned Width = Or.getType()->getScalarSizeInBits(); - - Instruction *Or0, *Or1; - if (!match(Or.getOperand(0), m_Instruction(Or0)) || - !match(Or.getOperand(1), m_Instruction(Or1))) - return std::nullopt; - - bool IsFshl = true; // Sub on LSHR. - SmallVector FShiftArgs; - - // First, find an or'd pair of opposite shifts: - // or (lshr ShVal0, ShAmt0), (shl ShVal1, ShAmt1) - if (isa(Or0) && isa(Or1)) { - Value *ShVal0, *ShVal1, *ShAmt0, *ShAmt1; - if (!match(Or0, - m_OneUse(m_LogicalShift(m_Value(ShVal0), m_Value(ShAmt0)))) || - !match(Or1, - m_OneUse(m_LogicalShift(m_Value(ShVal1), m_Value(ShAmt1)))) || - Or0->getOpcode() == Or1->getOpcode()) - return std::nullopt; - - // Canonicalize to or(shl(ShVal0, ShAmt0), lshr(ShVal1, ShAmt1)). - if (Or0->getOpcode() == BinaryOperator::LShr) { - std::swap(Or0, Or1); - std::swap(ShVal0, ShVal1); - std::swap(ShAmt0, ShAmt1); - } - assert(Or0->getOpcode() == BinaryOperator::Shl && - Or1->getOpcode() == BinaryOperator::LShr && - "Illegal or(shift,shift) pair"); - - // Match the shift amount operands for a funnel shift pattern. This always - // matches a subtraction on the R operand. - auto matchShiftAmount = [&](Value *L, Value *R, unsigned Width) -> Value * { - // Check for constant shift amounts that sum to the bitwidth. - const APInt *LI, *RI; - if (match(L, m_APIntAllowPoison(LI)) && match(R, m_APIntAllowPoison(RI))) - if (LI->ult(Width) && RI->ult(Width) && (*LI + *RI) == Width) - return ConstantInt::get(L->getType(), *LI); - - Constant *LC, *RC; - if (match(L, m_Constant(LC)) && match(R, m_Constant(RC)) && - match(L, - m_SpecificInt_ICMP(ICmpInst::ICMP_ULT, APInt(Width, Width))) && - match(R, - m_SpecificInt_ICMP(ICmpInst::ICMP_ULT, APInt(Width, Width))) && - match(ConstantExpr::getAdd(LC, RC), m_SpecificIntAllowPoison(Width))) - return ConstantExpr::mergeUndefsWith(LC, RC); - - // (shl ShVal, X) | (lshr ShVal, (Width - x)) iff X < Width. - // We limit this to X < Width in case the backend re-expands the - // intrinsic, and has to reintroduce a shift modulo operation (InstCombine - // might remove it after this fold). This still doesn't guarantee that the - // final codegen will match this original pattern. - if (match(R, m_OneUse(m_Sub(m_SpecificInt(Width), m_Specific(L))))) { - KnownBits KnownL = computeKnownBits(L, /*Depth*/ 0, &Or); - return KnownL.getMaxValue().ult(Width) ? L : nullptr; - } - - // For non-constant cases, the following patterns currently only work for - // rotation patterns. - // TODO: Add general funnel-shift compatible patterns. - if (ShVal0 != ShVal1) - return nullptr; - - // For non-constant cases we don't support non-pow2 shift masks. - // TODO: Is it worth matching urem as well? - if (!isPowerOf2_32(Width)) - return nullptr; - - // The shift amount may be masked with negation: - // (shl ShVal, (X & (Width - 1))) | (lshr ShVal, ((-X) & (Width - 1))) - Value *X; - unsigned Mask = Width - 1; - if (match(L, m_And(m_Value(X), m_SpecificInt(Mask))) && - match(R, m_And(m_Neg(m_Specific(X)), m_SpecificInt(Mask)))) - return X; - - // (shl ShVal, X) | (lshr ShVal, ((-X) & (Width - 1))) - if (match(R, m_And(m_Neg(m_Specific(L)), m_SpecificInt(Mask)))) - return L; - - // Similar to above, but the shift amount may be extended after masking, - // so return the extended value as the parameter for the intrinsic. - if (match(L, m_ZExt(m_And(m_Value(X), m_SpecificInt(Mask)))) && - match(R, - m_And(m_Neg(m_ZExt(m_And(m_Specific(X), m_SpecificInt(Mask)))), - m_SpecificInt(Mask)))) - return L; - - if (match(L, m_ZExt(m_And(m_Value(X), m_SpecificInt(Mask)))) && - match(R, m_ZExt(m_And(m_Neg(m_Specific(X)), m_SpecificInt(Mask))))) - return L; - - return nullptr; - }; - - Value *ShAmt = matchShiftAmount(ShAmt0, ShAmt1, Width); - if (!ShAmt) { - ShAmt = matchShiftAmount(ShAmt1, ShAmt0, Width); - IsFshl = false; // Sub on SHL. - } - if (!ShAmt) - return std::nullopt; - - FShiftArgs = {ShVal0, ShVal1, ShAmt}; - } else if (isa(Or0) || isa(Or1)) { - // If there are two 'or' instructions concat variables in opposite order: - // - // Slot1 and Slot2 are all zero bits. - // | Slot1 | Low | Slot2 | High | - // LowHigh = or (shl (zext Low), ZextLowShlAmt), (zext High) - // | Slot2 | High | Slot1 | Low | - // HighLow = or (shl (zext High), ZextHighShlAmt), (zext Low) - // - // the latter 'or' can be safely convert to - // -> HighLow = fshl LowHigh, LowHigh, ZextHighShlAmt - // if ZextLowShlAmt + ZextHighShlAmt == Width. - if (!isa(Or1)) - std::swap(Or0, Or1); - - Value *High, *ZextHigh, *Low; - const APInt *ZextHighShlAmt; - if (!match(Or0, - m_OneUse(m_Shl(m_Value(ZextHigh), m_APInt(ZextHighShlAmt))))) - return std::nullopt; - - if (!match(Or1, m_ZExt(m_Value(Low))) || - !match(ZextHigh, m_ZExt(m_Value(High)))) - return std::nullopt; - - unsigned HighSize = High->getType()->getScalarSizeInBits(); - unsigned LowSize = Low->getType()->getScalarSizeInBits(); - // Make sure High does not overlap with Low and most significant bits of - // High aren't shifted out. - if (ZextHighShlAmt->ult(LowSize) || ZextHighShlAmt->ugt(Width - HighSize)) - return std::nullopt; - - for (User *U : ZextHigh->users()) { - Value *X, *Y; - if (!match(U, m_Or(m_Value(X), m_Value(Y)))) - continue; - - if (!isa(Y)) - std::swap(X, Y); - - const APInt *ZextLowShlAmt; - if (!match(X, m_Shl(m_Specific(Or1), m_APInt(ZextLowShlAmt))) || - !match(Y, m_Specific(ZextHigh)) || !DT.dominates(U, &Or)) - continue; - - // HighLow is good concat. If sum of two shifts amount equals to Width, - // LowHigh must also be a good concat. - if (*ZextLowShlAmt + *ZextHighShlAmt != Width) - continue; - - // Low must not overlap with High and most significant bits of Low must - // not be shifted out. - assert(ZextLowShlAmt->uge(HighSize) && - ZextLowShlAmt->ule(Width - LowSize) && "Invalid concat"); - - FShiftArgs = {U, U, ConstantInt::get(Or0->getType(), *ZextHighShlAmt)}; - break; - } - } - - if (FShiftArgs.empty()) - return std::nullopt; - - Intrinsic::ID IID = IsFshl ? Intrinsic::fshl : Intrinsic::fshr; - return std::make_pair(IID, FShiftArgs); -} - -/// Match UB-safe variants of the funnel shift intrinsic. -static Instruction *matchFunnelShift(Instruction &Or, InstCombinerImpl &IC) { - if (auto Opt = IC.convertOrOfShiftsToFunnelShift(Or)) { - auto [IID, FShiftArgs] = *Opt; - Function *F = - Intrinsic::getOrInsertDeclaration(Or.getModule(), IID, Or.getType()); - return CallInst::Create(F, FShiftArgs); - } - - return nullptr; -} - -/// Attempt to combine or(zext(x),shl(zext(y),bw/2) concat packing patterns. -static Instruction *matchOrConcat(Instruction &Or, - InstCombiner::BuilderTy &Builder) { - assert(Or.getOpcode() == Instruction::Or && "bswap requires an 'or'"); - Value *Op0 = Or.getOperand(0), *Op1 = Or.getOperand(1); - Type *Ty = Or.getType(); - - unsigned Width = Ty->getScalarSizeInBits(); - if ((Width & 1) != 0) - return nullptr; - unsigned HalfWidth = Width / 2; - - // Canonicalize zext (lower half) to LHS. - if (!isa(Op0)) - std::swap(Op0, Op1); - - // Find lower/upper half. - Value *LowerSrc, *ShlVal, *UpperSrc; - const APInt *C; - if (!match(Op0, m_OneUse(m_ZExt(m_Value(LowerSrc)))) || - !match(Op1, m_OneUse(m_Shl(m_Value(ShlVal), m_APInt(C)))) || - !match(ShlVal, m_OneUse(m_ZExt(m_Value(UpperSrc))))) - return nullptr; - if (*C != HalfWidth || LowerSrc->getType() != UpperSrc->getType() || - LowerSrc->getType()->getScalarSizeInBits() != HalfWidth) - return nullptr; - - auto ConcatIntrinsicCalls = [&](Intrinsic::ID id, Value *Lo, Value *Hi) { - Value *NewLower = Builder.CreateZExt(Lo, Ty); - Value *NewUpper = Builder.CreateZExt(Hi, Ty); - NewUpper = Builder.CreateShl(NewUpper, HalfWidth); - Value *BinOp = Builder.CreateOr(NewLower, NewUpper); - return Builder.CreateIntrinsic(id, Ty, BinOp); - }; - - // BSWAP: Push the concat down, swapping the lower/upper sources. - // concat(bswap(x),bswap(y)) -> bswap(concat(x,y)) - Value *LowerBSwap, *UpperBSwap; - if (match(LowerSrc, m_BSwap(m_Value(LowerBSwap))) && - match(UpperSrc, m_BSwap(m_Value(UpperBSwap)))) - return ConcatIntrinsicCalls(Intrinsic::bswap, UpperBSwap, LowerBSwap); - - // BITREVERSE: Push the concat down, swapping the lower/upper sources. - // concat(bitreverse(x),bitreverse(y)) -> bitreverse(concat(x,y)) - Value *LowerBRev, *UpperBRev; - if (match(LowerSrc, m_BitReverse(m_Value(LowerBRev))) && - match(UpperSrc, m_BitReverse(m_Value(UpperBRev)))) - return ConcatIntrinsicCalls(Intrinsic::bitreverse, UpperBRev, LowerBRev); - - return nullptr; -} - -/// If all elements of two constant vectors are 0/-1 and inverses, return true. -static bool areInverseVectorBitmasks(Constant *C1, Constant *C2) { - unsigned NumElts = cast(C1->getType())->getNumElements(); - for (unsigned i = 0; i != NumElts; ++i) { - Constant *EltC1 = C1->getAggregateElement(i); - Constant *EltC2 = C2->getAggregateElement(i); - if (!EltC1 || !EltC2) - return false; - - // One element must be all ones, and the other must be all zeros. - if (!((match(EltC1, m_Zero()) && match(EltC2, m_AllOnes())) || - (match(EltC2, m_Zero()) && match(EltC1, m_AllOnes())))) - return false; - } - return true; -} - -/// We have an expression of the form (A & C) | (B & D). If A is a scalar or -/// vector composed of all-zeros or all-ones values and is the bitwise 'not' of -/// B, it can be used as the condition operand of a select instruction. -/// We will detect (A & C) | ~(B | D) when the flag ABIsTheSame enabled. -Value *InstCombinerImpl::getSelectCondition(Value *A, Value *B, - bool ABIsTheSame) { - // We may have peeked through bitcasts in the caller. - // Exit immediately if we don't have (vector) integer types. - Type *Ty = A->getType(); - if (!Ty->isIntOrIntVectorTy() || !B->getType()->isIntOrIntVectorTy()) - return nullptr; - - // If A is the 'not' operand of B and has enough signbits, we have our answer. - if (ABIsTheSame ? (A == B) : match(B, m_Not(m_Specific(A)))) { - // If these are scalars or vectors of i1, A can be used directly. - if (Ty->isIntOrIntVectorTy(1)) - return A; - - // If we look through a vector bitcast, the caller will bitcast the operands - // to match the condition's number of bits (N x i1). - // To make this poison-safe, disallow bitcast from wide element to narrow - // element. That could allow poison in lanes where it was not present in the - // original code. - A = peekThroughBitcast(A); - if (A->getType()->isIntOrIntVectorTy()) { - unsigned NumSignBits = ComputeNumSignBits(A); - if (NumSignBits == A->getType()->getScalarSizeInBits() && - NumSignBits <= Ty->getScalarSizeInBits()) - return Builder.CreateTrunc(A, CmpInst::makeCmpResultType(A->getType())); - } - return nullptr; - } - - // TODO: add support for sext and constant case - if (ABIsTheSame) - return nullptr; - - // If both operands are constants, see if the constants are inverse bitmasks. - Constant *AConst, *BConst; - if (match(A, m_Constant(AConst)) && match(B, m_Constant(BConst))) - if (AConst == ConstantExpr::getNot(BConst) && - ComputeNumSignBits(A) == Ty->getScalarSizeInBits()) - return Builder.CreateZExtOrTrunc(A, CmpInst::makeCmpResultType(Ty)); - - // Look for more complex patterns. The 'not' op may be hidden behind various - // casts. Look through sexts and bitcasts to find the booleans. - Value *Cond; - Value *NotB; - if (match(A, m_SExt(m_Value(Cond))) && - Cond->getType()->isIntOrIntVectorTy(1)) { - // A = sext i1 Cond; B = sext (not (i1 Cond)) - if (match(B, m_SExt(m_Not(m_Specific(Cond))))) - return Cond; - - // A = sext i1 Cond; B = not ({bitcast} (sext (i1 Cond))) - // TODO: The one-use checks are unnecessary or misplaced. If the caller - // checked for uses on logic ops/casts, that should be enough to - // make this transform worthwhile. - if (match(B, m_OneUse(m_Not(m_Value(NotB))))) { - NotB = peekThroughBitcast(NotB, true); - if (match(NotB, m_SExt(m_Specific(Cond)))) - return Cond; - } - } - - // All scalar (and most vector) possibilities should be handled now. - // Try more matches that only apply to non-splat constant vectors. - if (!Ty->isVectorTy()) - return nullptr; - - // If both operands are xor'd with constants using the same sexted boolean - // operand, see if the constants are inverse bitmasks. - // TODO: Use ConstantExpr::getNot()? - if (match(A, (m_Xor(m_SExt(m_Value(Cond)), m_Constant(AConst)))) && - match(B, (m_Xor(m_SExt(m_Specific(Cond)), m_Constant(BConst)))) && - Cond->getType()->isIntOrIntVectorTy(1) && - areInverseVectorBitmasks(AConst, BConst)) { - AConst = ConstantExpr::getTrunc(AConst, CmpInst::makeCmpResultType(Ty)); - return Builder.CreateXor(Cond, AConst); - } - return nullptr; -} - -/// We have an expression of the form (A & B) | (C & D). Try to simplify this -/// to "A' ? B : D", where A' is a boolean or vector of booleans. -/// When InvertFalseVal is set to true, we try to match the pattern -/// where we have peeked through a 'not' op and A and C are the same: -/// (A & B) | ~(A | D) --> (A & B) | (~A & ~D) --> A' ? B : ~D -Value *InstCombinerImpl::matchSelectFromAndOr(Value *A, Value *B, Value *C, - Value *D, bool InvertFalseVal) { - // The potential condition of the select may be bitcasted. In that case, look - // through its bitcast and the corresponding bitcast of the 'not' condition. - Type *OrigType = A->getType(); - A = peekThroughBitcast(A, true); - C = peekThroughBitcast(C, true); - if (Value *Cond = getSelectCondition(A, C, InvertFalseVal)) { - // ((bc Cond) & B) | ((bc ~Cond) & D) --> bc (select Cond, (bc B), (bc D)) - // If this is a vector, we may need to cast to match the condition's length. - // The bitcasts will either all exist or all not exist. The builder will - // not create unnecessary casts if the types already match. - Type *SelTy = A->getType(); - if (auto *VecTy = dyn_cast(Cond->getType())) { - // For a fixed or scalable vector get N from <{vscale x} N x iM> - unsigned Elts = VecTy->getElementCount().getKnownMinValue(); - // For a fixed or scalable vector, get the size in bits of N x iM; for a - // scalar this is just M. - unsigned SelEltSize = SelTy->getPrimitiveSizeInBits().getKnownMinValue(); - Type *EltTy = Builder.getIntNTy(SelEltSize / Elts); - SelTy = VectorType::get(EltTy, VecTy->getElementCount()); - } - Value *BitcastB = Builder.CreateBitCast(B, SelTy); - if (InvertFalseVal) - D = Builder.CreateNot(D); - Value *BitcastD = Builder.CreateBitCast(D, SelTy); - Value *Select = Builder.CreateSelect(Cond, BitcastB, BitcastD); - return Builder.CreateBitCast(Select, OrigType); - } - - return nullptr; -} - -// (icmp eq X, C) | (icmp ult Other, (X - C)) -> (icmp ule Other, (X - (C + 1))) -// (icmp ne X, C) & (icmp uge Other, (X - C)) -> (icmp ugt Other, (X - (C + 1))) -static Value *foldAndOrOfICmpEqConstantAndICmp(ICmpInst *LHS, ICmpInst *RHS, - bool IsAnd, bool IsLogical, - IRBuilderBase &Builder) { - Value *LHS0 = LHS->getOperand(0); - Value *RHS0 = RHS->getOperand(0); - Value *RHS1 = RHS->getOperand(1); - - ICmpInst::Predicate LPred = - IsAnd ? LHS->getInversePredicate() : LHS->getPredicate(); - ICmpInst::Predicate RPred = - IsAnd ? RHS->getInversePredicate() : RHS->getPredicate(); - - const APInt *CInt; - if (LPred != ICmpInst::ICMP_EQ || - !match(LHS->getOperand(1), m_APIntAllowPoison(CInt)) || - !LHS0->getType()->isIntOrIntVectorTy() || - !(LHS->hasOneUse() || RHS->hasOneUse())) - return nullptr; - - auto MatchRHSOp = [LHS0, CInt](const Value *RHSOp) { - return match(RHSOp, - m_Add(m_Specific(LHS0), m_SpecificIntAllowPoison(-*CInt))) || - (CInt->isZero() && RHSOp == LHS0); - }; - - Value *Other; - if (RPred == ICmpInst::ICMP_ULT && MatchRHSOp(RHS1)) - Other = RHS0; - else if (RPred == ICmpInst::ICMP_UGT && MatchRHSOp(RHS0)) - Other = RHS1; - else - return nullptr; - - if (IsLogical) - Other = Builder.CreateFreeze(Other); - - return Builder.CreateICmp( - IsAnd ? ICmpInst::ICMP_ULT : ICmpInst::ICMP_UGE, - Builder.CreateSub(LHS0, ConstantInt::get(LHS0->getType(), *CInt + 1)), - Other); -} - -/// Fold (icmp)&(icmp) or (icmp)|(icmp) if possible. -/// If IsLogical is true, then the and/or is in select form and the transform -/// must be poison-safe. -Value *InstCombinerImpl::foldAndOrOfICmps(ICmpInst *LHS, ICmpInst *RHS, - Instruction &I, bool IsAnd, - bool IsLogical) { - const SimplifyQuery Q = SQ.getWithInstruction(&I); - - ICmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate(); - Value *LHS0 = LHS->getOperand(0), *RHS0 = RHS->getOperand(0); - Value *LHS1 = LHS->getOperand(1), *RHS1 = RHS->getOperand(1); - - const APInt *LHSC = nullptr, *RHSC = nullptr; - match(LHS1, m_APInt(LHSC)); - match(RHS1, m_APInt(RHSC)); - - // (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B) - // (icmp1 A, B) & (icmp2 A, B) --> (icmp3 A, B) - if (predicatesFoldable(PredL, PredR)) { - if (LHS0 == RHS1 && LHS1 == RHS0) { - PredL = ICmpInst::getSwappedPredicate(PredL); - std::swap(LHS0, LHS1); - } - if (LHS0 == RHS0 && LHS1 == RHS1) { - unsigned Code = IsAnd ? getICmpCode(PredL) & getICmpCode(PredR) - : getICmpCode(PredL) | getICmpCode(PredR); - bool IsSigned = LHS->isSigned() || RHS->isSigned(); - return getNewICmpValue(Code, IsSigned, LHS0, LHS1, Builder); - } - } - - // handle (roughly): - // (icmp ne (A & B), C) | (icmp ne (A & D), E) - // (icmp eq (A & B), C) & (icmp eq (A & D), E) - if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, IsAnd, IsLogical, Builder, Q)) - return V; - - if (Value *V = - foldAndOrOfICmpEqConstantAndICmp(LHS, RHS, IsAnd, IsLogical, Builder)) - return V; - // We can treat logical like bitwise here, because both operands are used on - // the LHS, and as such poison from both will propagate. - if (Value *V = foldAndOrOfICmpEqConstantAndICmp(RHS, LHS, IsAnd, - /*IsLogical*/ false, Builder)) - return V; - - if (Value *V = - foldAndOrOfICmpsWithConstEq(LHS, RHS, IsAnd, IsLogical, Builder, Q)) - return V; - // We can convert this case to bitwise and, because both operands are used - // on the LHS, and as such poison from both will propagate. - if (Value *V = foldAndOrOfICmpsWithConstEq(RHS, LHS, IsAnd, - /*IsLogical=*/false, Builder, Q)) { - // If RHS is still used, we should drop samesign flag. - if (IsLogical && RHS->hasSameSign() && !RHS->use_empty()) { - RHS->setSameSign(false); - addToWorklist(RHS); - } - return V; - } - - if (Value *V = foldIsPowerOf2OrZero(LHS, RHS, IsAnd, Builder, *this)) - return V; - if (Value *V = foldIsPowerOf2OrZero(RHS, LHS, IsAnd, Builder, *this)) - return V; - - // TODO: One of these directions is fine with logical and/or, the other could - // be supported by inserting freeze. - if (!IsLogical) { - // E.g. (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n - // E.g. (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n - if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/!IsAnd)) - return V; - - // E.g. (icmp sgt x, n) | (icmp slt x, 0) --> icmp ugt x, n - // E.g. (icmp slt x, n) & (icmp sge x, 0) --> icmp ult x, n - if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/!IsAnd)) - return V; - } - - // TODO: Add conjugated or fold, check whether it is safe for logical and/or. - if (IsAnd && !IsLogical) - if (Value *V = foldSignedTruncationCheck(LHS, RHS, I, Builder)) - return V; - - if (Value *V = foldIsPowerOf2(LHS, RHS, IsAnd, Builder, *this)) - return V; - - if (Value *V = foldPowerOf2AndShiftedMask(LHS, RHS, IsAnd, Builder)) - return V; - - // TODO: Verify whether this is safe for logical and/or. - if (!IsLogical) { - if (Value *X = foldUnsignedUnderflowCheck(LHS, RHS, IsAnd, Q, Builder)) - return X; - if (Value *X = foldUnsignedUnderflowCheck(RHS, LHS, IsAnd, Q, Builder)) - return X; - } - - // (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0) - // (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0) - // TODO: Remove this and below when foldLogOpOfMaskedICmps can handle undefs. - if (PredL == (IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE) && - PredL == PredR && match(LHS1, m_ZeroInt()) && match(RHS1, m_ZeroInt()) && - LHS0->getType() == RHS0->getType() && - (!IsLogical || isGuaranteedNotToBePoison(RHS0))) { - Value *NewOr = Builder.CreateOr(LHS0, RHS0); - return Builder.CreateICmp(PredL, NewOr, - Constant::getNullValue(NewOr->getType())); - } - - // (icmp ne A, -1) | (icmp ne B, -1) --> (icmp ne (A&B), -1) - // (icmp eq A, -1) & (icmp eq B, -1) --> (icmp eq (A&B), -1) - if (PredL == (IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE) && - PredL == PredR && match(LHS1, m_AllOnes()) && match(RHS1, m_AllOnes()) && - LHS0->getType() == RHS0->getType() && - (!IsLogical || isGuaranteedNotToBePoison(RHS0))) { - Value *NewAnd = Builder.CreateAnd(LHS0, RHS0); - return Builder.CreateICmp(PredL, NewAnd, - Constant::getAllOnesValue(LHS0->getType())); - } - - if (!IsLogical) - if (Value *V = - foldAndOrOfICmpsWithPow2AndWithZero(Builder, LHS, RHS, IsAnd, Q)) - return V; - - // This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2). - if (!LHSC || !RHSC) - return nullptr; - - // (trunc x) == C1 & (and x, CA) == C2 -> (and x, CA|CMAX) == C1|C2 - // (trunc x) != C1 | (and x, CA) != C2 -> (and x, CA|CMAX) != C1|C2 - // where CMAX is the all ones value for the truncated type, - // iff the lower bits of C2 and CA are zero. - if (PredL == (IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE) && - PredL == PredR && LHS->hasOneUse() && RHS->hasOneUse()) { - Value *V; - const APInt *AndC, *SmallC = nullptr, *BigC = nullptr; - - // (trunc x) == C1 & (and x, CA) == C2 - // (and x, CA) == C2 & (trunc x) == C1 - if (match(RHS0, m_Trunc(m_Value(V))) && - match(LHS0, m_And(m_Specific(V), m_APInt(AndC)))) { - SmallC = RHSC; - BigC = LHSC; - } else if (match(LHS0, m_Trunc(m_Value(V))) && - match(RHS0, m_And(m_Specific(V), m_APInt(AndC)))) { - SmallC = LHSC; - BigC = RHSC; - } - - if (SmallC && BigC) { - unsigned BigBitSize = BigC->getBitWidth(); - unsigned SmallBitSize = SmallC->getBitWidth(); - - // Check that the low bits are zero. - APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize); - if ((Low & *AndC).isZero() && (Low & *BigC).isZero()) { - Value *NewAnd = Builder.CreateAnd(V, Low | *AndC); - APInt N = SmallC->zext(BigBitSize) | *BigC; - Value *NewVal = ConstantInt::get(NewAnd->getType(), N); - return Builder.CreateICmp(PredL, NewAnd, NewVal); - } - } - } - - // Match naive pattern (and its inverted form) for checking if two values - // share same sign. An example of the pattern: - // (icmp slt (X & Y), 0) | (icmp sgt (X | Y), -1) -> (icmp sgt (X ^ Y), -1) - // Inverted form (example): - // (icmp slt (X | Y), 0) & (icmp sgt (X & Y), -1) -> (icmp slt (X ^ Y), 0) - bool TrueIfSignedL, TrueIfSignedR; - if (isSignBitCheck(PredL, *LHSC, TrueIfSignedL) && - isSignBitCheck(PredR, *RHSC, TrueIfSignedR) && - (RHS->hasOneUse() || LHS->hasOneUse())) { - Value *X, *Y; - if (IsAnd) { - if ((TrueIfSignedL && !TrueIfSignedR && - match(LHS0, m_Or(m_Value(X), m_Value(Y))) && - match(RHS0, m_c_And(m_Specific(X), m_Specific(Y)))) || - (!TrueIfSignedL && TrueIfSignedR && - match(LHS0, m_And(m_Value(X), m_Value(Y))) && - match(RHS0, m_c_Or(m_Specific(X), m_Specific(Y))))) { - Value *NewXor = Builder.CreateXor(X, Y); - return Builder.CreateIsNeg(NewXor); - } - } else { - if ((TrueIfSignedL && !TrueIfSignedR && - match(LHS0, m_And(m_Value(X), m_Value(Y))) && - match(RHS0, m_c_Or(m_Specific(X), m_Specific(Y)))) || - (!TrueIfSignedL && TrueIfSignedR && - match(LHS0, m_Or(m_Value(X), m_Value(Y))) && - match(RHS0, m_c_And(m_Specific(X), m_Specific(Y))))) { - Value *NewXor = Builder.CreateXor(X, Y); - return Builder.CreateIsNotNeg(NewXor); - } - } - } - - return foldAndOrOfICmpsUsingRanges(LHS, RHS, IsAnd); -} - -/// If IsLogical is true, then the and/or is in select form and the transform -/// must be poison-safe. -Value *InstCombinerImpl::foldBooleanAndOr(Value *LHS, Value *RHS, - Instruction &I, bool IsAnd, - bool IsLogical) { - if (!LHS->getType()->isIntOrIntVectorTy(1)) - return nullptr; - - if (auto *LHSCmp = dyn_cast(LHS)) - if (auto *RHSCmp = dyn_cast(RHS)) - if (Value *Res = foldAndOrOfICmps(LHSCmp, RHSCmp, I, IsAnd, IsLogical)) - return Res; - - if (auto *LHSCmp = dyn_cast(LHS)) - if (auto *RHSCmp = dyn_cast(RHS)) - if (Value *Res = foldLogicOfFCmps(LHSCmp, RHSCmp, IsAnd, IsLogical)) - return Res; - - if (Value *Res = foldEqOfParts(LHS, RHS, IsAnd)) - return Res; - - return nullptr; -} - -static Value *foldOrOfInversions(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - assert(I.getOpcode() == Instruction::Or && - "Simplification only supports or at the moment."); - - Value *Cmp1, *Cmp2, *Cmp3, *Cmp4; - if (!match(I.getOperand(0), m_And(m_Value(Cmp1), m_Value(Cmp2))) || - !match(I.getOperand(1), m_And(m_Value(Cmp3), m_Value(Cmp4)))) - return nullptr; - - // Check if any two pairs of the and operations are inversions of each other. - if (isKnownInversion(Cmp1, Cmp3) && isKnownInversion(Cmp2, Cmp4)) - return Builder.CreateXor(Cmp1, Cmp4); - if (isKnownInversion(Cmp1, Cmp4) && isKnownInversion(Cmp2, Cmp3)) - return Builder.CreateXor(Cmp1, Cmp3); - - return nullptr; -} - -// FIXME: We use commutative matchers (m_c_*) for some, but not all, matches -// here. We should standardize that construct where it is needed or choose some -// other way to ensure that commutated variants of patterns are not missed. -Instruction *InstCombinerImpl::visitOr(BinaryOperator &I) { - if (Value *V = simplifyOrInst(I.getOperand(0), I.getOperand(1), - SQ.getWithInstruction(&I))) - return replaceInstUsesWith(I, V); - - if (SimplifyAssociativeOrCommutative(I)) - return &I; - - if (Instruction *X = foldVectorBinop(I)) - return X; - - if (Instruction *Phi = foldBinopWithPhiOperands(I)) - return Phi; - - // See if we can simplify any instructions used by the instruction whose sole - // purpose is to compute bits we don't care about. - if (SimplifyDemandedInstructionBits(I)) - return &I; - - // Do this before using distributive laws to catch simple and/or/not patterns. - if (Instruction *Xor = foldOrToXor(I, Builder)) - return Xor; - - if (Instruction *X = foldComplexAndOrPatterns(I, Builder)) - return X; - - // (A & B) | (C & D) -> A ^ D where A == ~C && B == ~D - // (A & B) | (C & D) -> A ^ C where A == ~D && B == ~C - if (Value *V = foldOrOfInversions(I, Builder)) - return replaceInstUsesWith(I, V); - - // (A&B)|(A&C) -> A&(B|C) etc - if (Value *V = foldUsingDistributiveLaws(I)) - return replaceInstUsesWith(I, V); - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - Type *Ty = I.getType(); - if (Ty->isIntOrIntVectorTy(1)) { - if (auto *SI0 = dyn_cast(Op0)) { - if (auto *R = - foldAndOrOfSelectUsingImpliedCond(Op1, *SI0, /* IsAnd */ false)) - return R; - } - if (auto *SI1 = dyn_cast(Op1)) { - if (auto *R = - foldAndOrOfSelectUsingImpliedCond(Op0, *SI1, /* IsAnd */ false)) - return R; - } - } - - if (Instruction *FoldedLogic = foldBinOpIntoSelectOrPhi(I)) - return FoldedLogic; - - if (Instruction *BitOp = matchBSwapOrBitReverse(I, /*MatchBSwaps*/ true, - /*MatchBitReversals*/ true)) - return BitOp; - - if (Instruction *Funnel = matchFunnelShift(I, *this)) - return Funnel; - - if (Instruction *Concat = matchOrConcat(I, Builder)) - return replaceInstUsesWith(I, Concat); - - if (Instruction *R = foldBinOpShiftWithShift(I)) - return R; - - if (Instruction *R = tryFoldInstWithCtpopWithNot(&I)) - return R; - - if (cast(I).isDisjoint()) { - if (Instruction *R = - foldAddLikeCommutative(I.getOperand(0), I.getOperand(1), - /*NSW=*/true, /*NUW=*/true)) - return R; - if (Instruction *R = - foldAddLikeCommutative(I.getOperand(1), I.getOperand(0), - /*NSW=*/true, /*NUW=*/true)) - return R; - } - - Value *X, *Y; - const APInt *CV; - if (match(&I, m_c_Or(m_OneUse(m_Xor(m_Value(X), m_APInt(CV))), m_Value(Y))) && - !CV->isAllOnes() && MaskedValueIsZero(Y, *CV, 0, &I)) { - // (X ^ C) | Y -> (X | Y) ^ C iff Y & C == 0 - // The check for a 'not' op is for efficiency (if Y is known zero --> ~X). - Value *Or = Builder.CreateOr(X, Y); - return BinaryOperator::CreateXor(Or, ConstantInt::get(Ty, *CV)); - } - - // If the operands have no common bits set: - // or (mul X, Y), X --> add (mul X, Y), X --> mul X, (Y + 1) - if (match(&I, m_c_DisjointOr(m_OneUse(m_Mul(m_Value(X), m_Value(Y))), - m_Deferred(X)))) { - Value *IncrementY = Builder.CreateAdd(Y, ConstantInt::get(Ty, 1)); - return BinaryOperator::CreateMul(X, IncrementY); - } - - // (A & C) | (B & D) - Value *A, *B, *C, *D; - if (match(Op0, m_And(m_Value(A), m_Value(C))) && - match(Op1, m_And(m_Value(B), m_Value(D)))) { - - // (A & C0) | (B & C1) - const APInt *C0, *C1; - if (match(C, m_APInt(C0)) && match(D, m_APInt(C1))) { - Value *X; - if (*C0 == ~*C1) { - // ((X | B) & MaskC) | (B & ~MaskC) -> (X & MaskC) | B - if (match(A, m_c_Or(m_Value(X), m_Specific(B)))) - return BinaryOperator::CreateOr(Builder.CreateAnd(X, *C0), B); - // (A & MaskC) | ((X | A) & ~MaskC) -> (X & ~MaskC) | A - if (match(B, m_c_Or(m_Specific(A), m_Value(X)))) - return BinaryOperator::CreateOr(Builder.CreateAnd(X, *C1), A); - - // ((X ^ B) & MaskC) | (B & ~MaskC) -> (X & MaskC) ^ B - if (match(A, m_c_Xor(m_Value(X), m_Specific(B)))) - return BinaryOperator::CreateXor(Builder.CreateAnd(X, *C0), B); - // (A & MaskC) | ((X ^ A) & ~MaskC) -> (X & ~MaskC) ^ A - if (match(B, m_c_Xor(m_Specific(A), m_Value(X)))) - return BinaryOperator::CreateXor(Builder.CreateAnd(X, *C1), A); - } - - if ((*C0 & *C1).isZero()) { - // ((X | B) & C0) | (B & C1) --> (X | B) & (C0 | C1) - // iff (C0 & C1) == 0 and (X & ~C0) == 0 - if (match(A, m_c_Or(m_Value(X), m_Specific(B))) && - MaskedValueIsZero(X, ~*C0, 0, &I)) { - Constant *C01 = ConstantInt::get(Ty, *C0 | *C1); - return BinaryOperator::CreateAnd(A, C01); - } - // (A & C0) | ((X | A) & C1) --> (X | A) & (C0 | C1) - // iff (C0 & C1) == 0 and (X & ~C1) == 0 - if (match(B, m_c_Or(m_Value(X), m_Specific(A))) && - MaskedValueIsZero(X, ~*C1, 0, &I)) { - Constant *C01 = ConstantInt::get(Ty, *C0 | *C1); - return BinaryOperator::CreateAnd(B, C01); - } - // ((X | C2) & C0) | ((X | C3) & C1) --> (X | C2 | C3) & (C0 | C1) - // iff (C0 & C1) == 0 and (C2 & ~C0) == 0 and (C3 & ~C1) == 0. - const APInt *C2, *C3; - if (match(A, m_Or(m_Value(X), m_APInt(C2))) && - match(B, m_Or(m_Specific(X), m_APInt(C3))) && - (*C2 & ~*C0).isZero() && (*C3 & ~*C1).isZero()) { - Value *Or = Builder.CreateOr(X, *C2 | *C3, "bitfield"); - Constant *C01 = ConstantInt::get(Ty, *C0 | *C1); - return BinaryOperator::CreateAnd(Or, C01); - } - } - } - - // Don't try to form a select if it's unlikely that we'll get rid of at - // least one of the operands. A select is generally more expensive than the - // 'or' that it is replacing. - if (Op0->hasOneUse() || Op1->hasOneUse()) { - // (Cond & C) | (~Cond & D) -> Cond ? C : D, and commuted variants. - if (Value *V = matchSelectFromAndOr(A, C, B, D)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(A, C, D, B)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(C, A, B, D)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(C, A, D, B)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(B, D, A, C)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(B, D, C, A)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(D, B, A, C)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(D, B, C, A)) - return replaceInstUsesWith(I, V); - } - } - - if (match(Op0, m_And(m_Value(A), m_Value(C))) && - match(Op1, m_Not(m_Or(m_Value(B), m_Value(D)))) && - (Op0->hasOneUse() || Op1->hasOneUse())) { - // (Cond & C) | ~(Cond | D) -> Cond ? C : ~D - if (Value *V = matchSelectFromAndOr(A, C, B, D, true)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(A, C, D, B, true)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(C, A, B, D, true)) - return replaceInstUsesWith(I, V); - if (Value *V = matchSelectFromAndOr(C, A, D, B, true)) - return replaceInstUsesWith(I, V); - } - - // (A ^ B) | ((B ^ C) ^ A) -> (A ^ B) | C - if (match(Op0, m_Xor(m_Value(A), m_Value(B)))) - if (match(Op1, - m_c_Xor(m_c_Xor(m_Specific(B), m_Value(C)), m_Specific(A))) || - match(Op1, m_c_Xor(m_c_Xor(m_Specific(A), m_Value(C)), m_Specific(B)))) - return BinaryOperator::CreateOr(Op0, C); - - // ((B ^ C) ^ A) | (A ^ B) -> (A ^ B) | C - if (match(Op1, m_Xor(m_Value(A), m_Value(B)))) - if (match(Op0, - m_c_Xor(m_c_Xor(m_Specific(B), m_Value(C)), m_Specific(A))) || - match(Op0, m_c_Xor(m_c_Xor(m_Specific(A), m_Value(C)), m_Specific(B)))) - return BinaryOperator::CreateOr(Op1, C); - - if (Instruction *DeMorgan = matchDeMorgansLaws(I, *this)) - return DeMorgan; - - // Canonicalize xor to the RHS. - bool SwappedForXor = false; - if (match(Op0, m_Xor(m_Value(), m_Value()))) { - std::swap(Op0, Op1); - SwappedForXor = true; - } - - if (match(Op1, m_Xor(m_Value(A), m_Value(B)))) { - // (A | ?) | (A ^ B) --> (A | ?) | B - // (B | ?) | (A ^ B) --> (B | ?) | A - if (match(Op0, m_c_Or(m_Specific(A), m_Value()))) - return BinaryOperator::CreateOr(Op0, B); - if (match(Op0, m_c_Or(m_Specific(B), m_Value()))) - return BinaryOperator::CreateOr(Op0, A); - - // (A & B) | (A ^ B) --> A | B - // (B & A) | (A ^ B) --> A | B - if (match(Op0, m_c_And(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateOr(A, B); - - // ~A | (A ^ B) --> ~(A & B) - // ~B | (A ^ B) --> ~(A & B) - // The swap above should always make Op0 the 'not'. - if ((Op0->hasOneUse() || Op1->hasOneUse()) && - (match(Op0, m_Not(m_Specific(A))) || match(Op0, m_Not(m_Specific(B))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(A, B)); - - // Same as above, but peek through an 'and' to the common operand: - // ~(A & ?) | (A ^ B) --> ~((A & ?) & B) - // ~(B & ?) | (A ^ B) --> ~((B & ?) & A) - Instruction *And; - if ((Op0->hasOneUse() || Op1->hasOneUse()) && - match(Op0, m_Not(m_CombineAnd(m_Instruction(And), - m_c_And(m_Specific(A), m_Value()))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(And, B)); - if ((Op0->hasOneUse() || Op1->hasOneUse()) && - match(Op0, m_Not(m_CombineAnd(m_Instruction(And), - m_c_And(m_Specific(B), m_Value()))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(And, A)); - - // (~A | C) | (A ^ B) --> ~(A & B) | C - // (~B | C) | (A ^ B) --> ~(A & B) | C - if (Op0->hasOneUse() && Op1->hasOneUse() && - (match(Op0, m_c_Or(m_Not(m_Specific(A)), m_Value(C))) || - match(Op0, m_c_Or(m_Not(m_Specific(B)), m_Value(C))))) { - Value *Nand = Builder.CreateNot(Builder.CreateAnd(A, B), "nand"); - return BinaryOperator::CreateOr(Nand, C); - } - } - - if (SwappedForXor) - std::swap(Op0, Op1); - - if (Value *Res = - foldBooleanAndOr(Op0, Op1, I, /*IsAnd=*/false, /*IsLogical=*/false)) - return replaceInstUsesWith(I, Res); - - if (match(Op1, m_OneUse(m_LogicalOr(m_Value(X), m_Value(Y))))) { - bool IsLogical = isa(Op1); - if (auto *V = reassociateBooleanAndOr(Op0, X, Y, I, /*IsAnd=*/false, - /*RHSIsLogical=*/IsLogical)) - return replaceInstUsesWith(I, V); - } - if (match(Op0, m_OneUse(m_LogicalOr(m_Value(X), m_Value(Y))))) { - bool IsLogical = isa(Op0); - if (auto *V = reassociateBooleanAndOr(Op1, X, Y, I, /*IsAnd=*/false, - /*RHSIsLogical=*/IsLogical)) - return replaceInstUsesWith(I, V); - } - - if (Instruction *FoldedFCmps = reassociateFCmps(I, Builder)) - return FoldedFCmps; - - if (Instruction *CastedOr = foldCastedBitwiseLogic(I)) - return CastedOr; - - if (Instruction *Sel = foldBinopOfSextBoolToSelect(I)) - return Sel; - - // or(sext(A), B) / or(B, sext(A)) --> A ? -1 : B, where A is i1 or . - // TODO: Move this into foldBinopOfSextBoolToSelect as a more generalized fold - // with binop identity constant. But creating a select with non-constant - // arm may not be reversible due to poison semantics. Is that a good - // canonicalization? - if (match(&I, m_c_Or(m_OneUse(m_SExt(m_Value(A))), m_Value(B))) && - A->getType()->isIntOrIntVectorTy(1)) - return SelectInst::Create(A, ConstantInt::getAllOnesValue(Ty), B); - - // Note: If we've gotten to the point of visiting the outer OR, then the - // inner one couldn't be simplified. If it was a constant, then it won't - // be simplified by a later pass either, so we try swapping the inner/outer - // ORs in the hopes that we'll be able to simplify it this way. - // (X|C) | V --> (X|V) | C - ConstantInt *CI; - if (Op0->hasOneUse() && !match(Op1, m_ConstantInt()) && - match(Op0, m_Or(m_Value(A), m_ConstantInt(CI)))) { - Value *Inner = Builder.CreateOr(A, Op1); - Inner->takeName(Op0); - return BinaryOperator::CreateOr(Inner, CI); - } - - // Change (or (bool?A:B),(bool?C:D)) --> (bool?(or A,C):(or B,D)) - // Since this OR statement hasn't been optimized further yet, we hope - // that this transformation will allow the new ORs to be optimized. - { - Value *X = nullptr, *Y = nullptr; - if (Op0->hasOneUse() && Op1->hasOneUse() && - match(Op0, m_Select(m_Value(X), m_Value(A), m_Value(B))) && - match(Op1, m_Select(m_Value(Y), m_Value(C), m_Value(D))) && X == Y) { - Value *orTrue = Builder.CreateOr(A, C); - Value *orFalse = Builder.CreateOr(B, D); - return SelectInst::Create(X, orTrue, orFalse); - } - } - - // or(ashr(subNSW(Y, X), ScalarSizeInBits(Y) - 1), X) --> X s> Y ? -1 : X. - { - Value *X, *Y; - if (match(&I, m_c_Or(m_OneUse(m_AShr( - m_NSWSub(m_Value(Y), m_Value(X)), - m_SpecificInt(Ty->getScalarSizeInBits() - 1))), - m_Deferred(X)))) { - Value *NewICmpInst = Builder.CreateICmpSGT(X, Y); - Value *AllOnes = ConstantInt::getAllOnesValue(Ty); - return SelectInst::Create(NewICmpInst, AllOnes, X); - } - } - - { - // ((A & B) ^ A) | ((A & B) ^ B) -> A ^ B - // (A ^ (A & B)) | (B ^ (A & B)) -> A ^ B - // ((A & B) ^ B) | ((A & B) ^ A) -> A ^ B - // (B ^ (A & B)) | (A ^ (A & B)) -> A ^ B - const auto TryXorOpt = [&](Value *Lhs, Value *Rhs) -> Instruction * { - if (match(Lhs, m_c_Xor(m_And(m_Value(A), m_Value(B)), m_Deferred(A))) && - match(Rhs, - m_c_Xor(m_And(m_Specific(A), m_Specific(B)), m_Specific(B)))) { - return BinaryOperator::CreateXor(A, B); - } - return nullptr; - }; - - if (Instruction *Result = TryXorOpt(Op0, Op1)) - return Result; - if (Instruction *Result = TryXorOpt(Op1, Op0)) - return Result; - } - - if (Instruction *V = - canonicalizeCondSignextOfHighBitExtractToSignextHighBitExtract(I)) - return V; - - CmpPredicate Pred; - Value *Mul, *Ov, *MulIsNotZero, *UMulWithOv; - // Check if the OR weakens the overflow condition for umul.with.overflow by - // treating any non-zero result as overflow. In that case, we overflow if both - // umul.with.overflow operands are != 0, as in that case the result can only - // be 0, iff the multiplication overflows. - if (match(&I, - m_c_Or(m_CombineAnd(m_ExtractValue<1>(m_Value(UMulWithOv)), - m_Value(Ov)), - m_CombineAnd( - m_SpecificICmp(ICmpInst::ICMP_NE, - m_CombineAnd(m_ExtractValue<0>( - m_Deferred(UMulWithOv)), - m_Value(Mul)), - m_ZeroInt()), - m_Value(MulIsNotZero)))) && - (Ov->hasOneUse() || (MulIsNotZero->hasOneUse() && Mul->hasOneUse()))) { - Value *A, *B; - if (match(UMulWithOv, m_Intrinsic( - m_Value(A), m_Value(B)))) { - Value *NotNullA = Builder.CreateIsNotNull(A); - Value *NotNullB = Builder.CreateIsNotNull(B); - return BinaryOperator::CreateAnd(NotNullA, NotNullB); - } - } - - /// Res, Overflow = xxx_with_overflow X, C1 - /// Try to canonicalize the pattern "Overflow | icmp pred Res, C2" into - /// "Overflow | icmp pred X, C2 +/- C1". - const WithOverflowInst *WO; - const Value *WOV; - const APInt *C1, *C2; - if (match(&I, m_c_Or(m_CombineAnd(m_ExtractValue<1>(m_CombineAnd( - m_WithOverflowInst(WO), m_Value(WOV))), - m_Value(Ov)), - m_OneUse(m_ICmp(Pred, m_ExtractValue<0>(m_Deferred(WOV)), - m_APInt(C2))))) && - (WO->getBinaryOp() == Instruction::Add || - WO->getBinaryOp() == Instruction::Sub) && - (ICmpInst::isEquality(Pred) || - WO->isSigned() == ICmpInst::isSigned(Pred)) && - match(WO->getRHS(), m_APInt(C1))) { - bool Overflow; - APInt NewC = WO->getBinaryOp() == Instruction::Add - ? (ICmpInst::isSigned(Pred) ? C2->ssub_ov(*C1, Overflow) - : C2->usub_ov(*C1, Overflow)) - : (ICmpInst::isSigned(Pred) ? C2->sadd_ov(*C1, Overflow) - : C2->uadd_ov(*C1, Overflow)); - if (!Overflow || ICmpInst::isEquality(Pred)) { - Value *NewCmp = Builder.CreateICmp( - Pred, WO->getLHS(), ConstantInt::get(WO->getLHS()->getType(), NewC)); - return BinaryOperator::CreateOr(Ov, NewCmp); - } - } - - // (~x) | y --> ~(x & (~y)) iff that gets rid of inversions - if (sinkNotIntoOtherHandOfLogicalOp(I)) - return &I; - - // Improve "get low bit mask up to and including bit X" pattern: - // (1 << X) | ((1 << X) + -1) --> -1 l>> (bitwidth(x) - 1 - X) - if (match(&I, m_c_Or(m_Add(m_Shl(m_One(), m_Value(X)), m_AllOnes()), - m_Shl(m_One(), m_Deferred(X)))) && - match(&I, m_c_Or(m_OneUse(m_Value()), m_Value()))) { - Value *Sub = Builder.CreateSub( - ConstantInt::get(Ty, Ty->getScalarSizeInBits() - 1), X); - return BinaryOperator::CreateLShr(Constant::getAllOnesValue(Ty), Sub); - } - - // An or recurrence w/loop invariant step is equivelent to (or start, step) - PHINode *PN = nullptr; - Value *Start = nullptr, *Step = nullptr; - if (matchSimpleRecurrence(&I, PN, Start, Step) && DT.dominates(Step, PN)) - return replaceInstUsesWith(I, Builder.CreateOr(Start, Step)); - - // (A & B) | (C | D) or (C | D) | (A & B) - // Can be combined if C or D is of type (A/B & X) - if (match(&I, m_c_Or(m_OneUse(m_And(m_Value(A), m_Value(B))), - m_OneUse(m_Or(m_Value(C), m_Value(D)))))) { - // (A & B) | (C | ?) -> C | (? | (A & B)) - // (A & B) | (C | ?) -> C | (? | (A & B)) - // (A & B) | (C | ?) -> C | (? | (A & B)) - // (A & B) | (C | ?) -> C | (? | (A & B)) - // (C | ?) | (A & B) -> C | (? | (A & B)) - // (C | ?) | (A & B) -> C | (? | (A & B)) - // (C | ?) | (A & B) -> C | (? | (A & B)) - // (C | ?) | (A & B) -> C | (? | (A & B)) - if (match(D, m_OneUse(m_c_And(m_Specific(A), m_Value()))) || - match(D, m_OneUse(m_c_And(m_Specific(B), m_Value())))) - return BinaryOperator::CreateOr( - C, Builder.CreateOr(D, Builder.CreateAnd(A, B))); - // (A & B) | (? | D) -> (? | (A & B)) | D - // (A & B) | (? | D) -> (? | (A & B)) | D - // (A & B) | (? | D) -> (? | (A & B)) | D - // (A & B) | (? | D) -> (? | (A & B)) | D - // (? | D) | (A & B) -> (? | (A & B)) | D - // (? | D) | (A & B) -> (? | (A & B)) | D - // (? | D) | (A & B) -> (? | (A & B)) | D - // (? | D) | (A & B) -> (? | (A & B)) | D - if (match(C, m_OneUse(m_c_And(m_Specific(A), m_Value()))) || - match(C, m_OneUse(m_c_And(m_Specific(B), m_Value())))) - return BinaryOperator::CreateOr( - Builder.CreateOr(C, Builder.CreateAnd(A, B)), D); - } - - if (Instruction *R = reassociateForUses(I, Builder)) - return R; - - if (Instruction *Canonicalized = canonicalizeLogicFirst(I, Builder)) - return Canonicalized; - - if (Instruction *Folded = foldLogicOfIsFPClass(I, Op0, Op1)) - return Folded; - - if (Instruction *Res = foldBinOpOfDisplacedShifts(I)) - return Res; - - // If we are setting the sign bit of a floating-point value, convert - // this to fneg(fabs), then cast back to integer. - // - // If the result isn't immediately cast back to a float, this will increase - // the number of instructions. This is still probably a better canonical form - // as it enables FP value tracking. - // - // Assumes any IEEE-represented type has the sign bit in the high bit. - // - // This is generous interpretation of noimplicitfloat, this is not a true - // floating-point operation. - Value *CastOp; - if (match(Op0, m_ElementWiseBitCast(m_Value(CastOp))) && - match(Op1, m_SignMask()) && - !Builder.GetInsertBlock()->getParent()->hasFnAttribute( - Attribute::NoImplicitFloat)) { - Type *EltTy = CastOp->getType()->getScalarType(); - if (EltTy->isFloatingPointTy() && EltTy->isIEEE()) { - Value *FAbs = Builder.CreateUnaryIntrinsic(Intrinsic::fabs, CastOp); - Value *FNegFAbs = Builder.CreateFNeg(FAbs); - return new BitCastInst(FNegFAbs, I.getType()); - } - } - - // (X & C1) | C2 -> X & (C1 | C2) iff (X & C2) == C2 - if (match(Op0, m_OneUse(m_And(m_Value(X), m_APInt(C1)))) && - match(Op1, m_APInt(C2))) { - KnownBits KnownX = computeKnownBits(X, /*Depth*/ 0, &I); - if ((KnownX.One & *C2) == *C2) - return BinaryOperator::CreateAnd(X, ConstantInt::get(Ty, *C1 | *C2)); - } - - if (Instruction *Res = foldBitwiseLogicWithIntrinsics(I, Builder)) - return Res; - - if (Value *V = - simplifyAndOrWithOpReplaced(Op0, Op1, Constant::getNullValue(Ty), - /*SimplifyOnly*/ false, *this)) - return BinaryOperator::CreateOr(V, Op1); - if (Value *V = - simplifyAndOrWithOpReplaced(Op1, Op0, Constant::getNullValue(Ty), - /*SimplifyOnly*/ false, *this)) - return BinaryOperator::CreateOr(Op0, V); - - if (cast(I).isDisjoint()) - if (Value *V = SimplifyAddWithRemainder(I)) - return replaceInstUsesWith(I, V); - - return nullptr; -} - -/// A ^ B can be specified using other logic ops in a variety of patterns. We -/// can fold these early and efficiently by morphing an existing instruction. -static Instruction *foldXorToXor(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - assert(I.getOpcode() == Instruction::Xor); - Value *Op0 = I.getOperand(0); - Value *Op1 = I.getOperand(1); - Value *A, *B; - - // There are 4 commuted variants for each of the basic patterns. - - // (A & B) ^ (A | B) -> A ^ B - // (A & B) ^ (B | A) -> A ^ B - // (A | B) ^ (A & B) -> A ^ B - // (A | B) ^ (B & A) -> A ^ B - if (match(&I, m_c_Xor(m_And(m_Value(A), m_Value(B)), - m_c_Or(m_Deferred(A), m_Deferred(B))))) - return BinaryOperator::CreateXor(A, B); - - // (A | ~B) ^ (~A | B) -> A ^ B - // (~B | A) ^ (~A | B) -> A ^ B - // (~A | B) ^ (A | ~B) -> A ^ B - // (B | ~A) ^ (A | ~B) -> A ^ B - if (match(&I, m_Xor(m_c_Or(m_Value(A), m_Not(m_Value(B))), - m_c_Or(m_Not(m_Deferred(A)), m_Deferred(B))))) - return BinaryOperator::CreateXor(A, B); - - // (A & ~B) ^ (~A & B) -> A ^ B - // (~B & A) ^ (~A & B) -> A ^ B - // (~A & B) ^ (A & ~B) -> A ^ B - // (B & ~A) ^ (A & ~B) -> A ^ B - if (match(&I, m_Xor(m_c_And(m_Value(A), m_Not(m_Value(B))), - m_c_And(m_Not(m_Deferred(A)), m_Deferred(B))))) - return BinaryOperator::CreateXor(A, B); - - // For the remaining cases we need to get rid of one of the operands. - if (!Op0->hasOneUse() && !Op1->hasOneUse()) - return nullptr; - - // (A | B) ^ ~(A & B) -> ~(A ^ B) - // (A | B) ^ ~(B & A) -> ~(A ^ B) - // (A & B) ^ ~(A | B) -> ~(A ^ B) - // (A & B) ^ ~(B | A) -> ~(A ^ B) - // Complexity sorting ensures the not will be on the right side. - if ((match(Op0, m_Or(m_Value(A), m_Value(B))) && - match(Op1, m_Not(m_c_And(m_Specific(A), m_Specific(B))))) || - (match(Op0, m_And(m_Value(A), m_Value(B))) && - match(Op1, m_Not(m_c_Or(m_Specific(A), m_Specific(B)))))) - return BinaryOperator::CreateNot(Builder.CreateXor(A, B)); - - return nullptr; -} - -Value *InstCombinerImpl::foldXorOfICmps(ICmpInst *LHS, ICmpInst *RHS, - BinaryOperator &I) { - assert(I.getOpcode() == Instruction::Xor && I.getOperand(0) == LHS && - I.getOperand(1) == RHS && "Should be 'xor' with these operands"); - - ICmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate(); - Value *LHS0 = LHS->getOperand(0), *LHS1 = LHS->getOperand(1); - Value *RHS0 = RHS->getOperand(0), *RHS1 = RHS->getOperand(1); - - if (predicatesFoldable(PredL, PredR)) { - if (LHS0 == RHS1 && LHS1 == RHS0) { - std::swap(LHS0, LHS1); - PredL = ICmpInst::getSwappedPredicate(PredL); - } - if (LHS0 == RHS0 && LHS1 == RHS1) { - // (icmp1 A, B) ^ (icmp2 A, B) --> (icmp3 A, B) - unsigned Code = getICmpCode(PredL) ^ getICmpCode(PredR); - bool IsSigned = LHS->isSigned() || RHS->isSigned(); - return getNewICmpValue(Code, IsSigned, LHS0, LHS1, Builder); - } - } - - // TODO: This can be generalized to compares of non-signbits using - // decomposeBitTestICmp(). It could be enhanced more by using (something like) - // foldLogOpOfMaskedICmps(). - const APInt *LC, *RC; - if (match(LHS1, m_APInt(LC)) && match(RHS1, m_APInt(RC)) && - LHS0->getType() == RHS0->getType() && - LHS0->getType()->isIntOrIntVectorTy()) { - // Convert xor of signbit tests to signbit test of xor'd values: - // (X > -1) ^ (Y > -1) --> (X ^ Y) < 0 - // (X < 0) ^ (Y < 0) --> (X ^ Y) < 0 - // (X > -1) ^ (Y < 0) --> (X ^ Y) > -1 - // (X < 0) ^ (Y > -1) --> (X ^ Y) > -1 - bool TrueIfSignedL, TrueIfSignedR; - if ((LHS->hasOneUse() || RHS->hasOneUse()) && - isSignBitCheck(PredL, *LC, TrueIfSignedL) && - isSignBitCheck(PredR, *RC, TrueIfSignedR)) { - Value *XorLR = Builder.CreateXor(LHS0, RHS0); - return TrueIfSignedL == TrueIfSignedR ? Builder.CreateIsNeg(XorLR) : - Builder.CreateIsNotNeg(XorLR); - } - - // Fold (icmp pred1 X, C1) ^ (icmp pred2 X, C2) - // into a single comparison using range-based reasoning. - if (LHS0 == RHS0) { - ConstantRange CR1 = ConstantRange::makeExactICmpRegion(PredL, *LC); - ConstantRange CR2 = ConstantRange::makeExactICmpRegion(PredR, *RC); - auto CRUnion = CR1.exactUnionWith(CR2); - auto CRIntersect = CR1.exactIntersectWith(CR2); - if (CRUnion && CRIntersect) - if (auto CR = CRUnion->exactIntersectWith(CRIntersect->inverse())) { - if (CR->isFullSet()) - return ConstantInt::getTrue(I.getType()); - if (CR->isEmptySet()) - return ConstantInt::getFalse(I.getType()); - - CmpInst::Predicate NewPred; - APInt NewC, Offset; - CR->getEquivalentICmp(NewPred, NewC, Offset); - - if ((Offset.isZero() && (LHS->hasOneUse() || RHS->hasOneUse())) || - (LHS->hasOneUse() && RHS->hasOneUse())) { - Value *NewV = LHS0; - Type *Ty = LHS0->getType(); - if (!Offset.isZero()) - NewV = Builder.CreateAdd(NewV, ConstantInt::get(Ty, Offset)); - return Builder.CreateICmp(NewPred, NewV, - ConstantInt::get(Ty, NewC)); - } - } - } - } - - // Instead of trying to imitate the folds for and/or, decompose this 'xor' - // into those logic ops. That is, try to turn this into an and-of-icmps - // because we have many folds for that pattern. - // - // This is based on a truth table definition of xor: - // X ^ Y --> (X | Y) & !(X & Y) - if (Value *OrICmp = simplifyBinOp(Instruction::Or, LHS, RHS, SQ)) { - // TODO: If OrICmp is true, then the definition of xor simplifies to !(X&Y). - // TODO: If OrICmp is false, the whole thing is false (InstSimplify?). - if (Value *AndICmp = simplifyBinOp(Instruction::And, LHS, RHS, SQ)) { - // TODO: Independently handle cases where the 'and' side is a constant. - ICmpInst *X = nullptr, *Y = nullptr; - if (OrICmp == LHS && AndICmp == RHS) { - // (LHS | RHS) & !(LHS & RHS) --> LHS & !RHS --> X & !Y - X = LHS; - Y = RHS; - } - if (OrICmp == RHS && AndICmp == LHS) { - // !(LHS & RHS) & (LHS | RHS) --> !LHS & RHS --> !Y & X - X = RHS; - Y = LHS; - } - if (X && Y && (Y->hasOneUse() || canFreelyInvertAllUsersOf(Y, &I))) { - // Invert the predicate of 'Y', thus inverting its output. - Y->setPredicate(Y->getInversePredicate()); - // So, are there other uses of Y? - if (!Y->hasOneUse()) { - // We need to adapt other uses of Y though. Get a value that matches - // the original value of Y before inversion. While this increases - // immediate instruction count, we have just ensured that all the - // users are freely-invertible, so that 'not' *will* get folded away. - BuilderTy::InsertPointGuard Guard(Builder); - // Set insertion point to right after the Y. - Builder.SetInsertPoint(Y->getParent(), ++(Y->getIterator())); - Value *NotY = Builder.CreateNot(Y, Y->getName() + ".not"); - // Replace all uses of Y (excluding the one in NotY!) with NotY. - Worklist.pushUsersToWorkList(*Y); - Y->replaceUsesWithIf(NotY, - [NotY](Use &U) { return U.getUser() != NotY; }); - } - // All done. - return Builder.CreateAnd(LHS, RHS); - } - } - } - - return nullptr; -} - -/// If we have a masked merge, in the canonical form of: -/// (assuming that A only has one use.) -/// | A | |B| -/// ((x ^ y) & M) ^ y -/// | D | -/// * If M is inverted: -/// | D | -/// ((x ^ y) & ~M) ^ y -/// We can canonicalize by swapping the final xor operand -/// to eliminate the 'not' of the mask. -/// ((x ^ y) & M) ^ x -/// * If M is a constant, and D has one use, we transform to 'and' / 'or' ops -/// because that shortens the dependency chain and improves analysis: -/// (x & M) | (y & ~M) -static Instruction *visitMaskedMerge(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - Value *B, *X, *D; - Value *M; - if (!match(&I, m_c_Xor(m_Value(B), - m_OneUse(m_c_And( - m_CombineAnd(m_c_Xor(m_Deferred(B), m_Value(X)), - m_Value(D)), - m_Value(M)))))) - return nullptr; - - Value *NotM; - if (match(M, m_Not(m_Value(NotM)))) { - // De-invert the mask and swap the value in B part. - Value *NewA = Builder.CreateAnd(D, NotM); - return BinaryOperator::CreateXor(NewA, X); - } - - Constant *C; - if (D->hasOneUse() && match(M, m_Constant(C))) { - // Propagating undef is unsafe. Clamp undef elements to -1. - Type *EltTy = C->getType()->getScalarType(); - C = Constant::replaceUndefsWith(C, ConstantInt::getAllOnesValue(EltTy)); - // Unfold. - Value *LHS = Builder.CreateAnd(X, C); - Value *NotC = Builder.CreateNot(C); - Value *RHS = Builder.CreateAnd(B, NotC); - return BinaryOperator::CreateOr(LHS, RHS); - } - - return nullptr; -} - -static Instruction *foldNotXor(BinaryOperator &I, - InstCombiner::BuilderTy &Builder) { - Value *X, *Y; - // FIXME: one-use check is not needed in general, but currently we are unable - // to fold 'not' into 'icmp', if that 'icmp' has multiple uses. (D35182) - if (!match(&I, m_Not(m_OneUse(m_Xor(m_Value(X), m_Value(Y)))))) - return nullptr; - - auto hasCommonOperand = [](Value *A, Value *B, Value *C, Value *D) { - return A == C || A == D || B == C || B == D; - }; - - Value *A, *B, *C, *D; - // Canonicalize ~((A & B) ^ (A | ?)) -> (A & B) | ~(A | ?) - // 4 commuted variants - if (match(X, m_And(m_Value(A), m_Value(B))) && - match(Y, m_Or(m_Value(C), m_Value(D))) && hasCommonOperand(A, B, C, D)) { - Value *NotY = Builder.CreateNot(Y); - return BinaryOperator::CreateOr(X, NotY); - }; - - // Canonicalize ~((A | ?) ^ (A & B)) -> (A & B) | ~(A | ?) - // 4 commuted variants - if (match(Y, m_And(m_Value(A), m_Value(B))) && - match(X, m_Or(m_Value(C), m_Value(D))) && hasCommonOperand(A, B, C, D)) { - Value *NotX = Builder.CreateNot(X); - return BinaryOperator::CreateOr(Y, NotX); - }; - - return nullptr; -} - -/// Canonicalize a shifty way to code absolute value to the more common pattern -/// that uses negation and select. -static Instruction *canonicalizeAbs(BinaryOperator &Xor, - InstCombiner::BuilderTy &Builder) { - assert(Xor.getOpcode() == Instruction::Xor && "Expected an xor instruction."); - - // There are 4 potential commuted variants. Move the 'ashr' candidate to Op1. - // We're relying on the fact that we only do this transform when the shift has - // exactly 2 uses and the add has exactly 1 use (otherwise, we might increase - // instructions). - Value *Op0 = Xor.getOperand(0), *Op1 = Xor.getOperand(1); - if (Op0->hasNUses(2)) - std::swap(Op0, Op1); - - Type *Ty = Xor.getType(); - Value *A; - const APInt *ShAmt; - if (match(Op1, m_AShr(m_Value(A), m_APInt(ShAmt))) && - Op1->hasNUses(2) && *ShAmt == Ty->getScalarSizeInBits() - 1 && - match(Op0, m_OneUse(m_c_Add(m_Specific(A), m_Specific(Op1))))) { - // Op1 = ashr i32 A, 31 ; smear the sign bit - // xor (add A, Op1), Op1 ; add -1 and flip bits if negative - // --> (A < 0) ? -A : A - Value *IsNeg = Builder.CreateIsNeg(A); - // Copy the nsw flags from the add to the negate. - auto *Add = cast(Op0); - Value *NegA = Add->hasNoUnsignedWrap() - ? Constant::getNullValue(A->getType()) - : Builder.CreateNeg(A, "", Add->hasNoSignedWrap()); - return SelectInst::Create(IsNeg, NegA, A); - } - return nullptr; -} - -static bool canFreelyInvert(InstCombiner &IC, Value *Op, - Instruction *IgnoredUser) { - auto *I = dyn_cast(Op); - return I && IC.isFreeToInvert(I, /*WillInvertAllUses=*/true) && - IC.canFreelyInvertAllUsersOf(I, IgnoredUser); -} - -static Value *freelyInvert(InstCombinerImpl &IC, Value *Op, - Instruction *IgnoredUser) { - auto *I = cast(Op); - IC.Builder.SetInsertPoint(*I->getInsertionPointAfterDef()); - Value *NotOp = IC.Builder.CreateNot(Op, Op->getName() + ".not"); - Op->replaceUsesWithIf(NotOp, - [NotOp](Use &U) { return U.getUser() != NotOp; }); - IC.freelyInvertAllUsersOf(NotOp, IgnoredUser); - return NotOp; -} - -// Transform -// z = ~(x &/| y) -// into: -// z = ((~x) |/& (~y)) -// iff both x and y are free to invert and all uses of z can be freely updated. -bool InstCombinerImpl::sinkNotIntoLogicalOp(Instruction &I) { - Value *Op0, *Op1; - if (!match(&I, m_LogicalOp(m_Value(Op0), m_Value(Op1)))) - return false; - - // If this logic op has not been simplified yet, just bail out and let that - // happen first. Otherwise, the code below may wrongly invert. - if (Op0 == Op1) - return false; - - Instruction::BinaryOps NewOpc = - match(&I, m_LogicalAnd()) ? Instruction::Or : Instruction::And; - bool IsBinaryOp = isa(I); - - // Can our users be adapted? - if (!InstCombiner::canFreelyInvertAllUsersOf(&I, /*IgnoredUser=*/nullptr)) - return false; - - // And can the operands be adapted? - if (!canFreelyInvert(*this, Op0, &I) || !canFreelyInvert(*this, Op1, &I)) - return false; - - Op0 = freelyInvert(*this, Op0, &I); - Op1 = freelyInvert(*this, Op1, &I); - - Builder.SetInsertPoint(*I.getInsertionPointAfterDef()); - Value *NewLogicOp; - if (IsBinaryOp) - NewLogicOp = Builder.CreateBinOp(NewOpc, Op0, Op1, I.getName() + ".not"); - else - NewLogicOp = - Builder.CreateLogicalOp(NewOpc, Op0, Op1, I.getName() + ".not"); - - replaceInstUsesWith(I, NewLogicOp); - // We can not just create an outer `not`, it will most likely be immediately - // folded back, reconstructing our initial pattern, and causing an - // infinite combine loop, so immediately manually fold it away. - freelyInvertAllUsersOf(NewLogicOp); - return true; -} - -// Transform -// z = (~x) &/| y -// into: -// z = ~(x |/& (~y)) -// iff y is free to invert and all uses of z can be freely updated. -bool InstCombinerImpl::sinkNotIntoOtherHandOfLogicalOp(Instruction &I) { - Value *Op0, *Op1; - if (!match(&I, m_LogicalOp(m_Value(Op0), m_Value(Op1)))) - return false; - Instruction::BinaryOps NewOpc = - match(&I, m_LogicalAnd()) ? Instruction::Or : Instruction::And; - bool IsBinaryOp = isa(I); - - Value *NotOp0 = nullptr; - Value *NotOp1 = nullptr; - Value **OpToInvert = nullptr; - if (match(Op0, m_Not(m_Value(NotOp0))) && canFreelyInvert(*this, Op1, &I)) { - Op0 = NotOp0; - OpToInvert = &Op1; - } else if (match(Op1, m_Not(m_Value(NotOp1))) && - canFreelyInvert(*this, Op0, &I)) { - Op1 = NotOp1; - OpToInvert = &Op0; - } else - return false; - - // And can our users be adapted? - if (!InstCombiner::canFreelyInvertAllUsersOf(&I, /*IgnoredUser=*/nullptr)) - return false; - - *OpToInvert = freelyInvert(*this, *OpToInvert, &I); - - Builder.SetInsertPoint(*I.getInsertionPointAfterDef()); - Value *NewBinOp; - if (IsBinaryOp) - NewBinOp = Builder.CreateBinOp(NewOpc, Op0, Op1, I.getName() + ".not"); - else - NewBinOp = Builder.CreateLogicalOp(NewOpc, Op0, Op1, I.getName() + ".not"); - replaceInstUsesWith(I, NewBinOp); - // We can not just create an outer `not`, it will most likely be immediately - // folded back, reconstructing our initial pattern, and causing an - // infinite combine loop, so immediately manually fold it away. - freelyInvertAllUsersOf(NewBinOp); - return true; -} - -Instruction *InstCombinerImpl::foldNot(BinaryOperator &I) { - Value *NotOp; - if (!match(&I, m_Not(m_Value(NotOp)))) - return nullptr; - - // Apply DeMorgan's Law for 'nand' / 'nor' logic with an inverted operand. - // We must eliminate the and/or (one-use) for these transforms to not increase - // the instruction count. - // - // ~(~X & Y) --> (X | ~Y) - // ~(Y & ~X) --> (X | ~Y) - // - // Note: The logical matches do not check for the commuted patterns because - // those are handled via SimplifySelectsFeedingBinaryOp(). - Type *Ty = I.getType(); - Value *X, *Y; - if (match(NotOp, m_OneUse(m_c_And(m_Not(m_Value(X)), m_Value(Y))))) { - Value *NotY = Builder.CreateNot(Y, Y->getName() + ".not"); - return BinaryOperator::CreateOr(X, NotY); - } - if (match(NotOp, m_OneUse(m_LogicalAnd(m_Not(m_Value(X)), m_Value(Y))))) { - Value *NotY = Builder.CreateNot(Y, Y->getName() + ".not"); - return SelectInst::Create(X, ConstantInt::getTrue(Ty), NotY); - } - - // ~(~X | Y) --> (X & ~Y) - // ~(Y | ~X) --> (X & ~Y) - if (match(NotOp, m_OneUse(m_c_Or(m_Not(m_Value(X)), m_Value(Y))))) { - Value *NotY = Builder.CreateNot(Y, Y->getName() + ".not"); - return BinaryOperator::CreateAnd(X, NotY); - } - if (match(NotOp, m_OneUse(m_LogicalOr(m_Not(m_Value(X)), m_Value(Y))))) { - Value *NotY = Builder.CreateNot(Y, Y->getName() + ".not"); - return SelectInst::Create(X, NotY, ConstantInt::getFalse(Ty)); - } - - // Is this a 'not' (~) fed by a binary operator? - BinaryOperator *NotVal; - if (match(NotOp, m_BinOp(NotVal))) { - // ~((-X) | Y) --> (X - 1) & (~Y) - if (match(NotVal, - m_OneUse(m_c_Or(m_OneUse(m_Neg(m_Value(X))), m_Value(Y))))) { - Value *DecX = Builder.CreateAdd(X, ConstantInt::getAllOnesValue(Ty)); - Value *NotY = Builder.CreateNot(Y); - return BinaryOperator::CreateAnd(DecX, NotY); - } - - // ~(~X >>s Y) --> (X >>s Y) - if (match(NotVal, m_AShr(m_Not(m_Value(X)), m_Value(Y)))) - return BinaryOperator::CreateAShr(X, Y); - - // Treat lshr with non-negative operand as ashr. - // ~(~X >>u Y) --> (X >>s Y) iff X is known negative - if (match(NotVal, m_LShr(m_Not(m_Value(X)), m_Value(Y))) && - isKnownNegative(X, SQ.getWithInstruction(NotVal))) - return BinaryOperator::CreateAShr(X, Y); - - // Bit-hack form of a signbit test for iN type: - // ~(X >>s (N - 1)) --> sext i1 (X > -1) to iN - unsigned FullShift = Ty->getScalarSizeInBits() - 1; - if (match(NotVal, m_OneUse(m_AShr(m_Value(X), m_SpecificInt(FullShift))))) { - Value *IsNotNeg = Builder.CreateIsNotNeg(X, "isnotneg"); - return new SExtInst(IsNotNeg, Ty); - } - - // If we are inverting a right-shifted constant, we may be able to eliminate - // the 'not' by inverting the constant and using the opposite shift type. - // Canonicalization rules ensure that only a negative constant uses 'ashr', - // but we must check that in case that transform has not fired yet. - - // ~(C >>s Y) --> ~C >>u Y (when inverting the replicated sign bits) - Constant *C; - if (match(NotVal, m_AShr(m_Constant(C), m_Value(Y))) && - match(C, m_Negative())) - return BinaryOperator::CreateLShr(ConstantExpr::getNot(C), Y); - - // ~(C >>u Y) --> ~C >>s Y (when inverting the replicated sign bits) - if (match(NotVal, m_LShr(m_Constant(C), m_Value(Y))) && - match(C, m_NonNegative())) - return BinaryOperator::CreateAShr(ConstantExpr::getNot(C), Y); - - // ~(X + C) --> ~C - X - if (match(NotVal, m_Add(m_Value(X), m_ImmConstant(C)))) - return BinaryOperator::CreateSub(ConstantExpr::getNot(C), X); - - // ~(X - Y) --> ~X + Y - // FIXME: is it really beneficial to sink the `not` here? - if (match(NotVal, m_Sub(m_Value(X), m_Value(Y)))) - if (isa(X) || NotVal->hasOneUse()) - return BinaryOperator::CreateAdd(Builder.CreateNot(X), Y); - - // ~(~X + Y) --> X - Y - if (match(NotVal, m_c_Add(m_Not(m_Value(X)), m_Value(Y)))) - return BinaryOperator::CreateWithCopiedFlags(Instruction::Sub, X, Y, - NotVal); - } - - // not (cmp A, B) = !cmp A, B - CmpPredicate Pred; - if (match(NotOp, m_Cmp(Pred, m_Value(), m_Value())) && - (NotOp->hasOneUse() || - InstCombiner::canFreelyInvertAllUsersOf(cast(NotOp), - /*IgnoredUser=*/nullptr))) { - cast(NotOp)->setPredicate(CmpInst::getInversePredicate(Pred)); - freelyInvertAllUsersOf(NotOp); - return &I; - } - - // Move a 'not' ahead of casts of a bool to enable logic reduction: - // not (bitcast (sext i1 X)) --> bitcast (sext (not i1 X)) - if (match(NotOp, m_OneUse(m_BitCast(m_OneUse(m_SExt(m_Value(X)))))) && X->getType()->isIntOrIntVectorTy(1)) { - Type *SextTy = cast(NotOp)->getSrcTy(); - Value *NotX = Builder.CreateNot(X); - Value *Sext = Builder.CreateSExt(NotX, SextTy); - return new BitCastInst(Sext, Ty); - } - - if (auto *NotOpI = dyn_cast(NotOp)) - if (sinkNotIntoLogicalOp(*NotOpI)) - return &I; - - // Eliminate a bitwise 'not' op of 'not' min/max by inverting the min/max: - // ~min(~X, ~Y) --> max(X, Y) - // ~max(~X, Y) --> min(X, ~Y) - auto *II = dyn_cast(NotOp); - if (II && II->hasOneUse()) { - if (match(NotOp, m_c_MaxOrMin(m_Not(m_Value(X)), m_Value(Y)))) { - Intrinsic::ID InvID = getInverseMinMaxIntrinsic(II->getIntrinsicID()); - Value *NotY = Builder.CreateNot(Y); - Value *InvMaxMin = Builder.CreateBinaryIntrinsic(InvID, X, NotY); - return replaceInstUsesWith(I, InvMaxMin); - } - - if (II->getIntrinsicID() == Intrinsic::is_fpclass) { - ConstantInt *ClassMask = cast(II->getArgOperand(1)); - II->setArgOperand( - 1, ConstantInt::get(ClassMask->getType(), - ~ClassMask->getZExtValue() & fcAllFlags)); - return replaceInstUsesWith(I, II); - } - } - - if (NotOp->hasOneUse()) { - // Pull 'not' into operands of select if both operands are one-use compares - // or one is one-use compare and the other one is a constant. - // Inverting the predicates eliminates the 'not' operation. - // Example: - // not (select ?, (cmp TPred, ?, ?), (cmp FPred, ?, ?) --> - // select ?, (cmp InvTPred, ?, ?), (cmp InvFPred, ?, ?) - // not (select ?, (cmp TPred, ?, ?), true --> - // select ?, (cmp InvTPred, ?, ?), false - if (auto *Sel = dyn_cast(NotOp)) { - Value *TV = Sel->getTrueValue(); - Value *FV = Sel->getFalseValue(); - auto *CmpT = dyn_cast(TV); - auto *CmpF = dyn_cast(FV); - bool InvertibleT = (CmpT && CmpT->hasOneUse()) || isa(TV); - bool InvertibleF = (CmpF && CmpF->hasOneUse()) || isa(FV); - if (InvertibleT && InvertibleF) { - if (CmpT) - CmpT->setPredicate(CmpT->getInversePredicate()); - else - Sel->setTrueValue(ConstantExpr::getNot(cast(TV))); - if (CmpF) - CmpF->setPredicate(CmpF->getInversePredicate()); - else - Sel->setFalseValue(ConstantExpr::getNot(cast(FV))); - return replaceInstUsesWith(I, Sel); - } - } - } - - if (Instruction *NewXor = foldNotXor(I, Builder)) - return NewXor; - - // TODO: Could handle multi-use better by checking if all uses of NotOp (other - // than I) can be inverted. - if (Value *R = getFreelyInverted(NotOp, NotOp->hasOneUse(), &Builder)) - return replaceInstUsesWith(I, R); - - return nullptr; -} - -// FIXME: We use commutative matchers (m_c_*) for some, but not all, matches -// here. We should standardize that construct where it is needed or choose some -// other way to ensure that commutated variants of patterns are not missed. -Instruction *InstCombinerImpl::visitXor(BinaryOperator &I) { - if (Value *V = simplifyXorInst(I.getOperand(0), I.getOperand(1), - SQ.getWithInstruction(&I))) - return replaceInstUsesWith(I, V); - - if (SimplifyAssociativeOrCommutative(I)) - return &I; - - if (Instruction *X = foldVectorBinop(I)) - return X; - - if (Instruction *Phi = foldBinopWithPhiOperands(I)) - return Phi; - - if (Instruction *NewXor = foldXorToXor(I, Builder)) - return NewXor; - - // (A&B)^(A&C) -> A&(B^C) etc - if (Value *V = foldUsingDistributiveLaws(I)) - return replaceInstUsesWith(I, V); - - // See if we can simplify any instructions used by the instruction whose sole - // purpose is to compute bits we don't care about. - if (SimplifyDemandedInstructionBits(I)) - return &I; - - if (Instruction *R = foldNot(I)) - return R; - - if (Instruction *R = foldBinOpShiftWithShift(I)) - return R; - - Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - Value *X, *Y, *M; - - // (X | Y) ^ M -> (X ^ M) ^ Y - // (X | Y) ^ M -> (Y ^ M) ^ X - if (match(&I, m_c_Xor(m_OneUse(m_DisjointOr(m_Value(X), m_Value(Y))), - m_Value(M)))) { - if (Value *XorAC = simplifyXorInst(X, M, SQ.getWithInstruction(&I))) - return BinaryOperator::CreateXor(XorAC, Y); - - if (Value *XorBC = simplifyXorInst(Y, M, SQ.getWithInstruction(&I))) - return BinaryOperator::CreateXor(XorBC, X); - } - - // Fold (X & M) ^ (Y & ~M) -> (X & M) | (Y & ~M) - // This it a special case in haveNoCommonBitsSet, but the computeKnownBits - // calls in there are unnecessary as SimplifyDemandedInstructionBits should - // have already taken care of those cases. - if (match(&I, m_c_Xor(m_c_And(m_Not(m_Value(M)), m_Value()), - m_c_And(m_Deferred(M), m_Value())))) { - if (isGuaranteedNotToBeUndef(M)) - return BinaryOperator::CreateDisjointOr(Op0, Op1); - else - return BinaryOperator::CreateOr(Op0, Op1); - } - - if (Instruction *Xor = visitMaskedMerge(I, Builder)) - return Xor; - - Constant *C1; - if (match(Op1, m_Constant(C1))) { - Constant *C2; - - if (match(Op0, m_OneUse(m_Or(m_Value(X), m_ImmConstant(C2)))) && - match(C1, m_ImmConstant())) { - // (X | C2) ^ C1 --> (X & ~C2) ^ (C1^C2) - C2 = Constant::replaceUndefsWith( - C2, Constant::getAllOnesValue(C2->getType()->getScalarType())); - Value *And = Builder.CreateAnd( - X, Constant::mergeUndefsWith(ConstantExpr::getNot(C2), C1)); - return BinaryOperator::CreateXor( - And, Constant::mergeUndefsWith(ConstantExpr::getXor(C1, C2), C1)); - } - - // Use DeMorgan and reassociation to eliminate a 'not' op. - if (match(Op0, m_OneUse(m_Or(m_Not(m_Value(X)), m_Constant(C2))))) { - // (~X | C2) ^ C1 --> ((X & ~C2) ^ -1) ^ C1 --> (X & ~C2) ^ ~C1 - Value *And = Builder.CreateAnd(X, ConstantExpr::getNot(C2)); - return BinaryOperator::CreateXor(And, ConstantExpr::getNot(C1)); - } - if (match(Op0, m_OneUse(m_And(m_Not(m_Value(X)), m_Constant(C2))))) { - // (~X & C2) ^ C1 --> ((X | ~C2) ^ -1) ^ C1 --> (X | ~C2) ^ ~C1 - Value *Or = Builder.CreateOr(X, ConstantExpr::getNot(C2)); - return BinaryOperator::CreateXor(Or, ConstantExpr::getNot(C1)); - } - - // Convert xor ([trunc] (ashr X, BW-1)), C => - // select(X >s -1, C, ~C) - // The ashr creates "AllZeroOrAllOne's", which then optionally inverses the - // constant depending on whether this input is less than 0. - const APInt *CA; - if (match(Op0, m_OneUse(m_TruncOrSelf( - m_AShr(m_Value(X), m_APIntAllowPoison(CA))))) && - *CA == X->getType()->getScalarSizeInBits() - 1 && - !match(C1, m_AllOnes())) { - assert(!C1->isZeroValue() && "Unexpected xor with 0"); - Value *IsNotNeg = Builder.CreateIsNotNeg(X); - return SelectInst::Create(IsNotNeg, Op1, Builder.CreateNot(Op1)); - } - } - - Type *Ty = I.getType(); - { - const APInt *RHSC; - if (match(Op1, m_APInt(RHSC))) { - Value *X; - const APInt *C; - // (C - X) ^ signmaskC --> (C + signmaskC) - X - if (RHSC->isSignMask() && match(Op0, m_Sub(m_APInt(C), m_Value(X)))) - return BinaryOperator::CreateSub(ConstantInt::get(Ty, *C + *RHSC), X); - - // (X + C) ^ signmaskC --> X + (C + signmaskC) - if (RHSC->isSignMask() && match(Op0, m_Add(m_Value(X), m_APInt(C)))) - return BinaryOperator::CreateAdd(X, ConstantInt::get(Ty, *C + *RHSC)); - - // (X | C) ^ RHSC --> X ^ (C ^ RHSC) iff X & C == 0 - if (match(Op0, m_Or(m_Value(X), m_APInt(C))) && - MaskedValueIsZero(X, *C, 0, &I)) - return BinaryOperator::CreateXor(X, ConstantInt::get(Ty, *C ^ *RHSC)); - - // When X is a power-of-two or zero and zero input is poison: - // ctlz(i32 X) ^ 31 --> cttz(X) - // cttz(i32 X) ^ 31 --> ctlz(X) - auto *II = dyn_cast(Op0); - if (II && II->hasOneUse() && *RHSC == Ty->getScalarSizeInBits() - 1) { - Intrinsic::ID IID = II->getIntrinsicID(); - if ((IID == Intrinsic::ctlz || IID == Intrinsic::cttz) && - match(II->getArgOperand(1), m_One()) && - isKnownToBeAPowerOfTwo(II->getArgOperand(0), /*OrZero */ true)) { - IID = (IID == Intrinsic::ctlz) ? Intrinsic::cttz : Intrinsic::ctlz; - Function *F = - Intrinsic::getOrInsertDeclaration(II->getModule(), IID, Ty); - return CallInst::Create(F, {II->getArgOperand(0), Builder.getTrue()}); - } - } - - // If RHSC is inverting the remaining bits of shifted X, - // canonicalize to a 'not' before the shift to help SCEV and codegen: - // (X << C) ^ RHSC --> ~X << C - if (match(Op0, m_OneUse(m_Shl(m_Value(X), m_APInt(C)))) && - *RHSC == APInt::getAllOnes(Ty->getScalarSizeInBits()).shl(*C)) { - Value *NotX = Builder.CreateNot(X); - return BinaryOperator::CreateShl(NotX, ConstantInt::get(Ty, *C)); - } - // (X >>u C) ^ RHSC --> ~X >>u C - if (match(Op0, m_OneUse(m_LShr(m_Value(X), m_APInt(C)))) && - *RHSC == APInt::getAllOnes(Ty->getScalarSizeInBits()).lshr(*C)) { - Value *NotX = Builder.CreateNot(X); - return BinaryOperator::CreateLShr(NotX, ConstantInt::get(Ty, *C)); - } - // TODO: We could handle 'ashr' here as well. That would be matching - // a 'not' op and moving it before the shift. Doing that requires - // preventing the inverse fold in canShiftBinOpWithConstantRHS(). - } - - // If we are XORing the sign bit of a floating-point value, convert - // this to fneg, then cast back to integer. - // - // This is generous interpretation of noimplicitfloat, this is not a true - // floating-point operation. - // - // Assumes any IEEE-represented type has the sign bit in the high bit. - // TODO: Unify with APInt matcher. This version allows undef unlike m_APInt - Value *CastOp; - if (match(Op0, m_ElementWiseBitCast(m_Value(CastOp))) && - match(Op1, m_SignMask()) && - !Builder.GetInsertBlock()->getParent()->hasFnAttribute( - Attribute::NoImplicitFloat)) { - Type *EltTy = CastOp->getType()->getScalarType(); - if (EltTy->isFloatingPointTy() && EltTy->isIEEE()) { - Value *FNeg = Builder.CreateFNeg(CastOp); - return new BitCastInst(FNeg, I.getType()); - } - } - } - - // FIXME: This should not be limited to scalar (pull into APInt match above). - { - Value *X; - ConstantInt *C1, *C2, *C3; - // ((X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3) - if (match(Op1, m_ConstantInt(C3)) && - match(Op0, m_LShr(m_Xor(m_Value(X), m_ConstantInt(C1)), - m_ConstantInt(C2))) && - Op0->hasOneUse()) { - // fold (C1 >> C2) ^ C3 - APInt FoldConst = C1->getValue().lshr(C2->getValue()); - FoldConst ^= C3->getValue(); - // Prepare the two operands. - auto *Opnd0 = Builder.CreateLShr(X, C2); - Opnd0->takeName(Op0); - return BinaryOperator::CreateXor(Opnd0, ConstantInt::get(Ty, FoldConst)); - } - } - - if (Instruction *FoldedLogic = foldBinOpIntoSelectOrPhi(I)) - return FoldedLogic; - - // Y ^ (X | Y) --> X & ~Y - // Y ^ (Y | X) --> X & ~Y - if (match(Op1, m_OneUse(m_c_Or(m_Value(X), m_Specific(Op0))))) - return BinaryOperator::CreateAnd(X, Builder.CreateNot(Op0)); - // (X | Y) ^ Y --> X & ~Y - // (Y | X) ^ Y --> X & ~Y - if (match(Op0, m_OneUse(m_c_Or(m_Value(X), m_Specific(Op1))))) - return BinaryOperator::CreateAnd(X, Builder.CreateNot(Op1)); - - // Y ^ (X & Y) --> ~X & Y - // Y ^ (Y & X) --> ~X & Y - if (match(Op1, m_OneUse(m_c_And(m_Value(X), m_Specific(Op0))))) - return BinaryOperator::CreateAnd(Op0, Builder.CreateNot(X)); - // (X & Y) ^ Y --> ~X & Y - // (Y & X) ^ Y --> ~X & Y - // Canonical form is (X & C) ^ C; don't touch that. - // TODO: A 'not' op is better for analysis and codegen, but demanded bits must - // be fixed to prefer that (otherwise we get infinite looping). - if (!match(Op1, m_Constant()) && - match(Op0, m_OneUse(m_c_And(m_Value(X), m_Specific(Op1))))) - return BinaryOperator::CreateAnd(Op1, Builder.CreateNot(X)); - - Value *A, *B, *C; - // (A ^ B) ^ (A | C) --> (~A & C) ^ B -- There are 4 commuted variants. - if (match(&I, m_c_Xor(m_OneUse(m_Xor(m_Value(A), m_Value(B))), - m_OneUse(m_c_Or(m_Deferred(A), m_Value(C)))))) - return BinaryOperator::CreateXor( - Builder.CreateAnd(Builder.CreateNot(A), C), B); - - // (A ^ B) ^ (B | C) --> (~B & C) ^ A -- There are 4 commuted variants. - if (match(&I, m_c_Xor(m_OneUse(m_Xor(m_Value(A), m_Value(B))), - m_OneUse(m_c_Or(m_Deferred(B), m_Value(C)))))) - return BinaryOperator::CreateXor( - Builder.CreateAnd(Builder.CreateNot(B), C), A); - - // (A & B) ^ (A ^ B) -> (A | B) - if (match(Op0, m_And(m_Value(A), m_Value(B))) && - match(Op1, m_c_Xor(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateOr(A, B); - // (A ^ B) ^ (A & B) -> (A | B) - if (match(Op0, m_Xor(m_Value(A), m_Value(B))) && - match(Op1, m_c_And(m_Specific(A), m_Specific(B)))) - return BinaryOperator::CreateOr(A, B); - - // (A & ~B) ^ ~A -> ~(A & B) - // (~B & A) ^ ~A -> ~(A & B) - if (match(Op0, m_c_And(m_Value(A), m_Not(m_Value(B)))) && - match(Op1, m_Not(m_Specific(A)))) - return BinaryOperator::CreateNot(Builder.CreateAnd(A, B)); - - // (~A & B) ^ A --> A | B -- There are 4 commuted variants. - if (match(&I, m_c_Xor(m_c_And(m_Not(m_Value(A)), m_Value(B)), m_Deferred(A)))) - return BinaryOperator::CreateOr(A, B); - - // (~A | B) ^ A --> ~(A & B) - if (match(Op0, m_OneUse(m_c_Or(m_Not(m_Specific(Op1)), m_Value(B))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(Op1, B)); - - // A ^ (~A | B) --> ~(A & B) - if (match(Op1, m_OneUse(m_c_Or(m_Not(m_Specific(Op0)), m_Value(B))))) - return BinaryOperator::CreateNot(Builder.CreateAnd(Op0, B)); - - // (A | B) ^ (A | C) --> (B ^ C) & ~A -- There are 4 commuted variants. - // TODO: Loosen one-use restriction if common operand is a constant. - Value *D; - if (match(Op0, m_OneUse(m_Or(m_Value(A), m_Value(B)))) && - match(Op1, m_OneUse(m_Or(m_Value(C), m_Value(D))))) { - if (B == C || B == D) - std::swap(A, B); - if (A == C) - std::swap(C, D); - if (A == D) { - Value *NotA = Builder.CreateNot(A); - return BinaryOperator::CreateAnd(Builder.CreateXor(B, C), NotA); - } - } - - // (A & B) ^ (A | C) --> A ? ~B : C -- There are 4 commuted variants. - if (I.getType()->isIntOrIntVectorTy(1) && - match(&I, m_c_Xor(m_OneUse(m_LogicalAnd(m_Value(A), m_Value(B))), - m_OneUse(m_LogicalOr(m_Value(C), m_Value(D)))))) { - bool NeedFreeze = isa(Op0) && isa(Op1) && B == D; - if (B == C || B == D) - std::swap(A, B); - if (A == C) - std::swap(C, D); - if (A == D) { - if (NeedFreeze) - A = Builder.CreateFreeze(A); - Value *NotB = Builder.CreateNot(B); - return SelectInst::Create(A, NotB, C); - } - } - - if (auto *LHS = dyn_cast(I.getOperand(0))) - if (auto *RHS = dyn_cast(I.getOperand(1))) - if (Value *V = foldXorOfICmps(LHS, RHS, I)) - return replaceInstUsesWith(I, V); - - if (Instruction *CastedXor = foldCastedBitwiseLogic(I)) - return CastedXor; - - if (Instruction *Abs = canonicalizeAbs(I, Builder)) - return Abs; - - // Otherwise, if all else failed, try to hoist the xor-by-constant: - // (X ^ C) ^ Y --> (X ^ Y) ^ C - // Just like we do in other places, we completely avoid the fold - // for constantexprs, at least to avoid endless combine loop. - if (match(&I, m_c_Xor(m_OneUse(m_Xor(m_CombineAnd(m_Value(X), - m_Unless(m_ConstantExpr())), - m_ImmConstant(C1))), - m_Value(Y)))) - return BinaryOperator::CreateXor(Builder.CreateXor(X, Y), C1); - - if (Instruction *R = reassociateForUses(I, Builder)) - return R; - - if (Instruction *Canonicalized = canonicalizeLogicFirst(I, Builder)) - return Canonicalized; - - if (Instruction *Folded = foldLogicOfIsFPClass(I, Op0, Op1)) - return Folded; - - if (Instruction *Folded = canonicalizeConditionalNegationViaMathToSelect(I)) - return Folded; - - if (Instruction *Res = foldBinOpOfDisplacedShifts(I)) - return Res; - - if (Instruction *Res = foldBitwiseLogicWithIntrinsics(I, Builder)) - return Res; - - return nullptr; -} diff --git a/llvm/tools/llvm-objcopy/CommonOpts.td b/llvm/tools/llvm-objcopy/CommonOpts.td index c247c93f6e0f2..5b15191f54605 100644 --- a/llvm/tools/llvm-objcopy/CommonOpts.td +++ b/llvm/tools/llvm-objcopy/CommonOpts.td @@ -117,6 +117,8 @@ def regex def version : Flag<["--"], "version">, HelpText<"Print the version and exit.">; +def verbose : Flag<["--"], "verbose">, + HelpText<"Prints the removed symbols and sections">; def V : Flag<["-"], "V">, Alias, HelpText<"Alias for --version">; diff --git a/llvm/tools/llvm-objcopy/ObjcopyOptions.cpp b/llvm/tools/llvm-objcopy/ObjcopyOptions.cpp index 0d209590655ef..7a0d719756081 100644 --- a/llvm/tools/llvm-objcopy/ObjcopyOptions.cpp +++ b/llvm/tools/llvm-objcopy/ObjcopyOptions.cpp @@ -1103,6 +1103,7 @@ objcopy::parseObjcopyOptions(ArrayRef ArgsArr, OBJCOPY_verify_note_sections, OBJCOPY_no_verify_note_sections, true); Config.OnlyKeepDebug = InputArgs.hasArg(OBJCOPY_only_keep_debug); + Config.Verbose = InputArgs.hasArg(OBJCOPY_verbose); ELFConfig.KeepFileSymbols = InputArgs.hasArg(OBJCOPY_keep_file_symbols); MachOConfig.KeepUndefined = InputArgs.hasArg(OBJCOPY_keep_undefined); Config.DecompressDebugSections = @@ -1586,6 +1587,7 @@ objcopy::parseStripOptions(ArrayRef RawArgsArr, Config.StripAllGNU = InputArgs.hasArg(STRIP_strip_all_gnu); MachOConfig.StripSwiftSymbols = InputArgs.hasArg(STRIP_strip_swift_symbols); Config.OnlyKeepDebug = InputArgs.hasArg(STRIP_only_keep_debug); + Config.Verbose = InputArgs.hasArg(STRIP_verbose); ELFConfig.KeepFileSymbols = InputArgs.hasArg(STRIP_keep_file_symbols); MachOConfig.KeepUndefined = InputArgs.hasArg(STRIP_keep_undefined);