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54f1e04f45
This is prep work before changing the callers to also use APInt which will allow folds for splat vectors. Currently, the callers have ConstantInt guards in place, so no functional change intended with this commit. llvm-svn: 280282
2727 lines
108 KiB
C++
2727 lines
108 KiB
C++
//===- InstCombineAndOrXor.cpp --------------------------------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the visitAnd, visitOr, and visitXor functions.
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//
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//===----------------------------------------------------------------------===//
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#include "InstCombineInternal.h"
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#include "llvm/Analysis/InstructionSimplify.h"
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#include "llvm/IR/ConstantRange.h"
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#include "llvm/IR/Intrinsics.h"
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#include "llvm/IR/PatternMatch.h"
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#include "llvm/Transforms/Utils/CmpInstAnalysis.h"
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#include "llvm/Transforms/Utils/Local.h"
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using namespace llvm;
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using namespace PatternMatch;
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#define DEBUG_TYPE "instcombine"
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static inline Value *dyn_castNotVal(Value *V) {
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// If this is not(not(x)) don't return that this is a not: we want the two
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// not's to be folded first.
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if (BinaryOperator::isNot(V)) {
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Value *Operand = BinaryOperator::getNotArgument(V);
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if (!IsFreeToInvert(Operand, Operand->hasOneUse()))
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return Operand;
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}
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// Constants can be considered to be not'ed values...
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if (ConstantInt *C = dyn_cast<ConstantInt>(V))
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return ConstantInt::get(C->getType(), ~C->getValue());
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return nullptr;
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}
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/// Similar to getICmpCode but for FCmpInst. This encodes a fcmp predicate into
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/// a four bit mask.
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static unsigned getFCmpCode(FCmpInst::Predicate CC) {
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assert(FCmpInst::FCMP_FALSE <= CC && CC <= FCmpInst::FCMP_TRUE &&
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"Unexpected FCmp predicate!");
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// Take advantage of the bit pattern of FCmpInst::Predicate here.
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// U L G E
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static_assert(FCmpInst::FCMP_FALSE == 0, ""); // 0 0 0 0
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static_assert(FCmpInst::FCMP_OEQ == 1, ""); // 0 0 0 1
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static_assert(FCmpInst::FCMP_OGT == 2, ""); // 0 0 1 0
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static_assert(FCmpInst::FCMP_OGE == 3, ""); // 0 0 1 1
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static_assert(FCmpInst::FCMP_OLT == 4, ""); // 0 1 0 0
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static_assert(FCmpInst::FCMP_OLE == 5, ""); // 0 1 0 1
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static_assert(FCmpInst::FCMP_ONE == 6, ""); // 0 1 1 0
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static_assert(FCmpInst::FCMP_ORD == 7, ""); // 0 1 1 1
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static_assert(FCmpInst::FCMP_UNO == 8, ""); // 1 0 0 0
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static_assert(FCmpInst::FCMP_UEQ == 9, ""); // 1 0 0 1
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static_assert(FCmpInst::FCMP_UGT == 10, ""); // 1 0 1 0
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static_assert(FCmpInst::FCMP_UGE == 11, ""); // 1 0 1 1
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static_assert(FCmpInst::FCMP_ULT == 12, ""); // 1 1 0 0
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static_assert(FCmpInst::FCMP_ULE == 13, ""); // 1 1 0 1
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static_assert(FCmpInst::FCMP_UNE == 14, ""); // 1 1 1 0
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static_assert(FCmpInst::FCMP_TRUE == 15, ""); // 1 1 1 1
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return CC;
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}
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/// This is the complement of getICmpCode, which turns an opcode and two
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/// operands into either a constant true or false, or a brand new ICmp
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/// instruction. The sign is passed in to determine which kind of predicate to
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/// use in the new icmp instruction.
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static Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
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InstCombiner::BuilderTy *Builder) {
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ICmpInst::Predicate NewPred;
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if (Value *NewConstant = getICmpValue(Sign, Code, LHS, RHS, NewPred))
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return NewConstant;
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return Builder->CreateICmp(NewPred, LHS, RHS);
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}
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/// This is the complement of getFCmpCode, which turns an opcode and two
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/// operands into either a FCmp instruction, or a true/false constant.
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static Value *getFCmpValue(unsigned Code, Value *LHS, Value *RHS,
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InstCombiner::BuilderTy *Builder) {
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const auto Pred = static_cast<FCmpInst::Predicate>(Code);
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assert(FCmpInst::FCMP_FALSE <= Pred && Pred <= FCmpInst::FCMP_TRUE &&
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"Unexpected FCmp predicate!");
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if (Pred == FCmpInst::FCMP_FALSE)
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return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
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if (Pred == FCmpInst::FCMP_TRUE)
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return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
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return Builder->CreateFCmp(Pred, LHS, RHS);
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}
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/// \brief Transform BITWISE_OP(BSWAP(A),BSWAP(B)) to BSWAP(BITWISE_OP(A, B))
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/// \param I Binary operator to transform.
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/// \return Pointer to node that must replace the original binary operator, or
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/// null pointer if no transformation was made.
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Value *InstCombiner::SimplifyBSwap(BinaryOperator &I) {
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IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
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// Can't do vectors.
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if (I.getType()->isVectorTy()) return nullptr;
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// Can only do bitwise ops.
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unsigned Op = I.getOpcode();
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if (Op != Instruction::And && Op != Instruction::Or &&
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Op != Instruction::Xor)
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return nullptr;
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Value *OldLHS = I.getOperand(0);
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Value *OldRHS = I.getOperand(1);
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ConstantInt *ConstLHS = dyn_cast<ConstantInt>(OldLHS);
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ConstantInt *ConstRHS = dyn_cast<ConstantInt>(OldRHS);
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IntrinsicInst *IntrLHS = dyn_cast<IntrinsicInst>(OldLHS);
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IntrinsicInst *IntrRHS = dyn_cast<IntrinsicInst>(OldRHS);
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bool IsBswapLHS = (IntrLHS && IntrLHS->getIntrinsicID() == Intrinsic::bswap);
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bool IsBswapRHS = (IntrRHS && IntrRHS->getIntrinsicID() == Intrinsic::bswap);
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if (!IsBswapLHS && !IsBswapRHS)
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return nullptr;
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if (!IsBswapLHS && !ConstLHS)
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return nullptr;
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if (!IsBswapRHS && !ConstRHS)
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return nullptr;
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/// OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
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/// OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )
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Value *NewLHS = IsBswapLHS ? IntrLHS->getOperand(0) :
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Builder->getInt(ConstLHS->getValue().byteSwap());
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Value *NewRHS = IsBswapRHS ? IntrRHS->getOperand(0) :
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Builder->getInt(ConstRHS->getValue().byteSwap());
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Value *BinOp = nullptr;
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if (Op == Instruction::And)
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BinOp = Builder->CreateAnd(NewLHS, NewRHS);
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else if (Op == Instruction::Or)
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BinOp = Builder->CreateOr(NewLHS, NewRHS);
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else //if (Op == Instruction::Xor)
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BinOp = Builder->CreateXor(NewLHS, NewRHS);
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Function *F = Intrinsic::getDeclaration(I.getModule(), Intrinsic::bswap, ITy);
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return Builder->CreateCall(F, BinOp);
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}
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/// This handles expressions of the form ((val OP C1) & C2). Where
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/// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
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/// guaranteed to be a binary operator.
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Instruction *InstCombiner::OptAndOp(Instruction *Op,
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ConstantInt *OpRHS,
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ConstantInt *AndRHS,
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BinaryOperator &TheAnd) {
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Value *X = Op->getOperand(0);
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Constant *Together = nullptr;
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if (!Op->isShift())
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Together = ConstantExpr::getAnd(AndRHS, OpRHS);
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switch (Op->getOpcode()) {
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case Instruction::Xor:
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if (Op->hasOneUse()) {
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// (X ^ C1) & C2 --> (X & C2) ^ (C1&C2)
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Value *And = Builder->CreateAnd(X, AndRHS);
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And->takeName(Op);
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return BinaryOperator::CreateXor(And, Together);
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}
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break;
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case Instruction::Or:
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if (Op->hasOneUse()){
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if (Together != OpRHS) {
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// (X | C1) & C2 --> (X | (C1&C2)) & C2
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Value *Or = Builder->CreateOr(X, Together);
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Or->takeName(Op);
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return BinaryOperator::CreateAnd(Or, AndRHS);
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}
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ConstantInt *TogetherCI = dyn_cast<ConstantInt>(Together);
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if (TogetherCI && !TogetherCI->isZero()){
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// (X | C1) & C2 --> (X & (C2^(C1&C2))) | C1
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// NOTE: This reduces the number of bits set in the & mask, which
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// can expose opportunities for store narrowing.
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Together = ConstantExpr::getXor(AndRHS, Together);
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Value *And = Builder->CreateAnd(X, Together);
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And->takeName(Op);
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return BinaryOperator::CreateOr(And, OpRHS);
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}
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}
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break;
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case Instruction::Add:
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if (Op->hasOneUse()) {
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// Adding a one to a single bit bit-field should be turned into an XOR
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// of the bit. First thing to check is to see if this AND is with a
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// single bit constant.
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const APInt &AndRHSV = AndRHS->getValue();
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// If there is only one bit set.
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if (AndRHSV.isPowerOf2()) {
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// Ok, at this point, we know that we are masking the result of the
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// ADD down to exactly one bit. If the constant we are adding has
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// no bits set below this bit, then we can eliminate the ADD.
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const APInt& AddRHS = OpRHS->getValue();
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// Check to see if any bits below the one bit set in AndRHSV are set.
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if ((AddRHS & (AndRHSV-1)) == 0) {
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// If not, the only thing that can effect the output of the AND is
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// the bit specified by AndRHSV. If that bit is set, the effect of
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// the XOR is to toggle the bit. If it is clear, then the ADD has
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// no effect.
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if ((AddRHS & AndRHSV) == 0) { // Bit is not set, noop
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TheAnd.setOperand(0, X);
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return &TheAnd;
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} else {
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// Pull the XOR out of the AND.
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Value *NewAnd = Builder->CreateAnd(X, AndRHS);
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NewAnd->takeName(Op);
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return BinaryOperator::CreateXor(NewAnd, AndRHS);
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}
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}
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}
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}
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break;
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case Instruction::Shl: {
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// We know that the AND will not produce any of the bits shifted in, so if
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// the anded constant includes them, clear them now!
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//
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uint32_t BitWidth = AndRHS->getType()->getBitWidth();
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uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
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APInt ShlMask(APInt::getHighBitsSet(BitWidth, BitWidth-OpRHSVal));
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ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShlMask);
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if (CI->getValue() == ShlMask)
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// Masking out bits that the shift already masks.
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return replaceInstUsesWith(TheAnd, Op); // No need for the and.
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if (CI != AndRHS) { // Reducing bits set in and.
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TheAnd.setOperand(1, CI);
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return &TheAnd;
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}
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break;
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}
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case Instruction::LShr: {
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// We know that the AND will not produce any of the bits shifted in, so if
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// the anded constant includes them, clear them now! This only applies to
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// unsigned shifts, because a signed shr may bring in set bits!
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//
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uint32_t BitWidth = AndRHS->getType()->getBitWidth();
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uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
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APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
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ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShrMask);
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if (CI->getValue() == ShrMask)
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// Masking out bits that the shift already masks.
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return replaceInstUsesWith(TheAnd, Op);
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if (CI != AndRHS) {
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TheAnd.setOperand(1, CI); // Reduce bits set in and cst.
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return &TheAnd;
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}
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break;
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}
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case Instruction::AShr:
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// Signed shr.
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// See if this is shifting in some sign extension, then masking it out
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// with an and.
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if (Op->hasOneUse()) {
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uint32_t BitWidth = AndRHS->getType()->getBitWidth();
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uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
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APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
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Constant *C = Builder->getInt(AndRHS->getValue() & ShrMask);
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if (C == AndRHS) { // Masking out bits shifted in.
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// (Val ashr C1) & C2 -> (Val lshr C1) & C2
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// Make the argument unsigned.
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Value *ShVal = Op->getOperand(0);
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ShVal = Builder->CreateLShr(ShVal, OpRHS, Op->getName());
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return BinaryOperator::CreateAnd(ShVal, AndRHS, TheAnd.getName());
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}
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}
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break;
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}
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return nullptr;
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}
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/// Emit a computation of: (V >= Lo && V < Hi) if Inside is true, otherwise
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/// (V < Lo || V >= Hi). This method expects that Lo <= Hi. IsSigned indicates
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/// whether to treat V, Lo, and Hi as signed or not.
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Value *InstCombiner::insertRangeTest(Value *V, const APInt &Lo, const APInt &Hi,
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bool isSigned, bool Inside) {
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assert((isSigned ? Lo.sle(Hi) : Lo.ule(Hi)) &&
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"Lo is not <= Hi in range emission code!");
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Type *Ty = V->getType();
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if (Lo == Hi)
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return Inside ? ConstantInt::getFalse(Ty) : ConstantInt::getTrue(Ty);
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// V >= Min && V < Hi --> V < Hi
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// V < Min || V >= Hi --> V >= Hi
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ICmpInst::Predicate Pred = Inside ? ICmpInst::ICMP_ULT : ICmpInst::ICMP_UGE;
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if (isSigned ? Lo.isMinSignedValue() : Lo.isMinValue()) {
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Pred = isSigned ? ICmpInst::getSignedPredicate(Pred) : Pred;
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return Builder->CreateICmp(Pred, V, ConstantInt::get(Ty, Hi));
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}
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// V >= Lo && V < Hi --> V - Lo u< Hi - Lo
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// V < Lo || V >= Hi --> V - Lo u>= Hi - Lo
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Value *VMinusLo =
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Builder->CreateSub(V, ConstantInt::get(Ty, Lo), V->getName() + ".off");
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Constant *HiMinusLo = ConstantInt::get(Ty, Hi - Lo);
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return Builder->CreateICmp(Pred, VMinusLo, HiMinusLo);
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}
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/// Returns true iff Val consists of one contiguous run of 1s with any number
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/// of 0s on either side. The 1s are allowed to wrap from LSB to MSB,
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/// so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
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/// not, since all 1s are not contiguous.
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static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) {
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const APInt& V = Val->getValue();
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uint32_t BitWidth = Val->getType()->getBitWidth();
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if (!APIntOps::isShiftedMask(BitWidth, V)) return false;
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// look for the first zero bit after the run of ones
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MB = BitWidth - ((V - 1) ^ V).countLeadingZeros();
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// look for the first non-zero bit
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ME = V.getActiveBits();
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return true;
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}
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/// This is part of an expression (LHS +/- RHS) & Mask, where isSub determines
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/// whether the operator is a sub. If we can fold one of the following xforms:
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///
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/// ((A & N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == Mask
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/// ((A | N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
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/// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0
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///
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/// return (A +/- B).
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///
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Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS,
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ConstantInt *Mask, bool isSub,
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Instruction &I) {
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Instruction *LHSI = dyn_cast<Instruction>(LHS);
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if (!LHSI || LHSI->getNumOperands() != 2 ||
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!isa<ConstantInt>(LHSI->getOperand(1))) return nullptr;
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ConstantInt *N = cast<ConstantInt>(LHSI->getOperand(1));
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switch (LHSI->getOpcode()) {
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default: return nullptr;
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case Instruction::And:
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if (ConstantExpr::getAnd(N, Mask) == Mask) {
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// If the AndRHS is a power of two minus one (0+1+), this is simple.
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if ((Mask->getValue().countLeadingZeros() +
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Mask->getValue().countPopulation()) ==
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Mask->getValue().getBitWidth())
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break;
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// Otherwise, if Mask is 0+1+0+, and if B is known to have the low 0+
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// part, we don't need any explicit masks to take them out of A. If that
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// is all N is, ignore it.
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uint32_t MB = 0, ME = 0;
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if (isRunOfOnes(Mask, MB, ME)) { // begin/end bit of run, inclusive
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uint32_t BitWidth = cast<IntegerType>(RHS->getType())->getBitWidth();
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APInt Mask(APInt::getLowBitsSet(BitWidth, MB-1));
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if (MaskedValueIsZero(RHS, Mask, 0, &I))
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break;
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}
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}
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return nullptr;
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case Instruction::Or:
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case Instruction::Xor:
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// If the AndRHS is a power of two minus one (0+1+), and N&Mask == 0
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if ((Mask->getValue().countLeadingZeros() +
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Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth()
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&& ConstantExpr::getAnd(N, Mask)->isNullValue())
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break;
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return nullptr;
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}
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if (isSub)
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return Builder->CreateSub(LHSI->getOperand(0), RHS, "fold");
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return Builder->CreateAdd(LHSI->getOperand(0), RHS, "fold");
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}
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/// enum for classifying (icmp eq (A & B), C) and (icmp ne (A & B), C)
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/// One of A and B is considered the mask, the other the value. This is
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/// described as the "AMask" or "BMask" part of the enum. If the enum
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/// contains only "Mask", then both A and B can be considered masks.
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/// If A is the mask, then it was proven, that (A & C) == C. This
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/// is trivial if C == A, or C == 0. If both A and C are constants, this
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/// proof is also easy.
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/// For the following explanations we assume that A is the mask.
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/// The part "AllOnes" declares, that the comparison is true only
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/// if (A & B) == A, or all bits of A are set in B.
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/// Example: (icmp eq (A & 3), 3) -> FoldMskICmp_AMask_AllOnes
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/// The part "AllZeroes" declares, that the comparison is true only
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/// if (A & B) == 0, or all bits of A are cleared in B.
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/// Example: (icmp eq (A & 3), 0) -> FoldMskICmp_Mask_AllZeroes
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/// The part "Mixed" declares, that (A & B) == C and C might or might not
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/// contain any number of one bits and zero bits.
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/// Example: (icmp eq (A & 3), 1) -> FoldMskICmp_AMask_Mixed
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/// The Part "Not" means, that in above descriptions "==" should be replaced
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/// by "!=".
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/// Example: (icmp ne (A & 3), 3) -> FoldMskICmp_AMask_NotAllOnes
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/// If the mask A contains a single bit, then the following is equivalent:
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/// (icmp eq (A & B), A) equals (icmp ne (A & B), 0)
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/// (icmp ne (A & B), A) equals (icmp eq (A & B), 0)
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enum MaskedICmpType {
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FoldMskICmp_AMask_AllOnes = 1,
|
|
FoldMskICmp_AMask_NotAllOnes = 2,
|
|
FoldMskICmp_BMask_AllOnes = 4,
|
|
FoldMskICmp_BMask_NotAllOnes = 8,
|
|
FoldMskICmp_Mask_AllZeroes = 16,
|
|
FoldMskICmp_Mask_NotAllZeroes = 32,
|
|
FoldMskICmp_AMask_Mixed = 64,
|
|
FoldMskICmp_AMask_NotMixed = 128,
|
|
FoldMskICmp_BMask_Mixed = 256,
|
|
FoldMskICmp_BMask_NotMixed = 512
|
|
};
|
|
|
|
/// Return the set of pattern classes (from MaskedICmpType)
|
|
/// that (icmp SCC (A & B), C) satisfies.
|
|
static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C,
|
|
ICmpInst::Predicate SCC)
|
|
{
|
|
ConstantInt *ACst = dyn_cast<ConstantInt>(A);
|
|
ConstantInt *BCst = dyn_cast<ConstantInt>(B);
|
|
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
|
|
bool icmp_eq = (SCC == ICmpInst::ICMP_EQ);
|
|
bool icmp_abit = (ACst && !ACst->isZero() &&
|
|
ACst->getValue().isPowerOf2());
|
|
bool icmp_bbit = (BCst && !BCst->isZero() &&
|
|
BCst->getValue().isPowerOf2());
|
|
unsigned result = 0;
|
|
if (CCst && CCst->isZero()) {
|
|
// if C is zero, then both A and B qualify as mask
|
|
result |= (icmp_eq ? (FoldMskICmp_Mask_AllZeroes |
|
|
FoldMskICmp_AMask_Mixed |
|
|
FoldMskICmp_BMask_Mixed)
|
|
: (FoldMskICmp_Mask_NotAllZeroes |
|
|
FoldMskICmp_AMask_NotMixed |
|
|
FoldMskICmp_BMask_NotMixed));
|
|
if (icmp_abit)
|
|
result |= (icmp_eq ? (FoldMskICmp_AMask_NotAllOnes |
|
|
FoldMskICmp_AMask_NotMixed)
|
|
: (FoldMskICmp_AMask_AllOnes |
|
|
FoldMskICmp_AMask_Mixed));
|
|
if (icmp_bbit)
|
|
result |= (icmp_eq ? (FoldMskICmp_BMask_NotAllOnes |
|
|
FoldMskICmp_BMask_NotMixed)
|
|
: (FoldMskICmp_BMask_AllOnes |
|
|
FoldMskICmp_BMask_Mixed));
|
|
return result;
|
|
}
|
|
if (A == C) {
|
|
result |= (icmp_eq ? (FoldMskICmp_AMask_AllOnes |
|
|
FoldMskICmp_AMask_Mixed)
|
|
: (FoldMskICmp_AMask_NotAllOnes |
|
|
FoldMskICmp_AMask_NotMixed));
|
|
if (icmp_abit)
|
|
result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
|
|
FoldMskICmp_AMask_NotMixed)
|
|
: (FoldMskICmp_Mask_AllZeroes |
|
|
FoldMskICmp_AMask_Mixed));
|
|
} else if (ACst && CCst &&
|
|
ConstantExpr::getAnd(ACst, CCst) == CCst) {
|
|
result |= (icmp_eq ? FoldMskICmp_AMask_Mixed
|
|
: FoldMskICmp_AMask_NotMixed);
|
|
}
|
|
if (B == C) {
|
|
result |= (icmp_eq ? (FoldMskICmp_BMask_AllOnes |
|
|
FoldMskICmp_BMask_Mixed)
|
|
: (FoldMskICmp_BMask_NotAllOnes |
|
|
FoldMskICmp_BMask_NotMixed));
|
|
if (icmp_bbit)
|
|
result |= (icmp_eq ? (FoldMskICmp_Mask_NotAllZeroes |
|
|
FoldMskICmp_BMask_NotMixed)
|
|
: (FoldMskICmp_Mask_AllZeroes |
|
|
FoldMskICmp_BMask_Mixed));
|
|
} else if (BCst && CCst &&
|
|
ConstantExpr::getAnd(BCst, CCst) == CCst) {
|
|
result |= (icmp_eq ? FoldMskICmp_BMask_Mixed
|
|
: FoldMskICmp_BMask_NotMixed);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/// 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 & (FoldMskICmp_AMask_AllOnes | FoldMskICmp_BMask_AllOnes |
|
|
FoldMskICmp_Mask_AllZeroes | FoldMskICmp_AMask_Mixed |
|
|
FoldMskICmp_BMask_Mixed))
|
|
<< 1;
|
|
|
|
NewMask |=
|
|
(Mask & (FoldMskICmp_AMask_NotAllOnes | FoldMskICmp_BMask_NotAllOnes |
|
|
FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_AMask_NotMixed |
|
|
FoldMskICmp_BMask_NotMixed))
|
|
>> 1;
|
|
|
|
return NewMask;
|
|
}
|
|
|
|
/// Handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
|
|
/// Return the set of pattern classes (from MaskedICmpType)
|
|
/// that both LHS and RHS satisfy.
|
|
static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
|
|
Value*& B, Value*& C,
|
|
Value*& D, Value*& E,
|
|
ICmpInst *LHS, ICmpInst *RHS,
|
|
ICmpInst::Predicate &LHSCC,
|
|
ICmpInst::Predicate &RHSCC) {
|
|
if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType()) return 0;
|
|
// vectors are not (yet?) supported
|
|
if (LHS->getOperand(0)->getType()->isVectorTy()) return 0;
|
|
|
|
// 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.
|
|
Value *L1 = LHS->getOperand(0);
|
|
Value *L2 = LHS->getOperand(1);
|
|
Value *L11,*L12,*L21,*L22;
|
|
// Check whether the icmp can be decomposed into a bit test.
|
|
if (decomposeBitTestICmp(LHS, LHSCC, L11, L12, L2)) {
|
|
L21 = L22 = L1 = nullptr;
|
|
} else {
|
|
// Look for ANDs in the LHS icmp.
|
|
if (!L1->getType()->isIntegerTy()) {
|
|
// You can icmp pointers, for example. They really aren't masks.
|
|
L11 = L12 = nullptr;
|
|
} else 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 (!L2->getType()->isIntegerTy()) {
|
|
// You can icmp pointers, for example. They really aren't masks.
|
|
L21 = L22 = nullptr;
|
|
} else 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(LHSCC))
|
|
return 0;
|
|
|
|
Value *R1 = RHS->getOperand(0);
|
|
Value *R2 = RHS->getOperand(1);
|
|
Value *R11,*R12;
|
|
bool ok = false;
|
|
if (decomposeBitTestICmp(RHS, RHSCC, 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 0;
|
|
}
|
|
E = R2; R1 = nullptr; ok = true;
|
|
} else if (R1->getType()->isIntegerTy()) {
|
|
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;
|
|
}
|
|
}
|
|
|
|
// Bail if RHS was a icmp that can't be decomposed into an equality.
|
|
if (!ICmpInst::isEquality(RHSCC))
|
|
return 0;
|
|
|
|
// Look for ANDs on the right side of the RHS icmp.
|
|
if (!ok && R2->getType()->isIntegerTy()) {
|
|
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; ok = true;
|
|
} else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
|
|
A = R12; D = R11; E = R1; ok = true;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
if (!ok)
|
|
return 0;
|
|
|
|
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 = getTypeOfMaskedICmp(A, B, C, LHSCC);
|
|
unsigned RightType = getTypeOfMaskedICmp(A, D, E, RHSCC);
|
|
return LeftType & RightType;
|
|
}
|
|
|
|
/// Try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
|
|
/// into a single (icmp(A & X) ==/!= Y).
|
|
static Value *foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd,
|
|
llvm::InstCombiner::BuilderTy *Builder) {
|
|
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr, *E = nullptr;
|
|
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
|
|
unsigned Mask = foldLogOpOfMaskedICmpsHelper(A, B, C, D, E, LHS, RHS,
|
|
LHSCC, RHSCC);
|
|
if (Mask == 0) return nullptr;
|
|
assert(ICmpInst::isEquality(LHSCC) && ICmpInst::isEquality(RHSCC) &&
|
|
"foldLogOpOfMaskedICmpsHelper must return an equality predicate.");
|
|
|
|
// 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 & FoldMskICmp_Mask_AllZeroes) {
|
|
// (icmp eq (A & B), 0) & (icmp eq (A & D), 0)
|
|
// -> (icmp eq (A & (B|D)), 0)
|
|
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 & FoldMskICmp_BMask_AllOnes) {
|
|
// (icmp eq (A & B), B) & (icmp eq (A & D), D)
|
|
// -> (icmp eq (A & (B|D)), (B|D))
|
|
Value *NewOr = Builder->CreateOr(B, D);
|
|
Value *NewAnd = Builder->CreateAnd(A, NewOr);
|
|
return Builder->CreateICmp(NewCC, NewAnd, NewOr);
|
|
}
|
|
if (Mask & FoldMskICmp_AMask_AllOnes) {
|
|
// (icmp eq (A & B), A) & (icmp eq (A & D), A)
|
|
// -> (icmp eq (A & (B&D)), A)
|
|
Value *NewAnd1 = Builder->CreateAnd(B, D);
|
|
Value *NewAnd2 = Builder->CreateAnd(A, NewAnd1);
|
|
return Builder->CreateICmp(NewCC, NewAnd2, A);
|
|
}
|
|
|
|
// Remaining cases assume at least that B and D are constant, and depend on
|
|
// their actual values. This isn't strictly necessary, just a "handle the
|
|
// easy cases for now" decision.
|
|
ConstantInt *BCst = dyn_cast<ConstantInt>(B);
|
|
if (!BCst) return nullptr;
|
|
ConstantInt *DCst = dyn_cast<ConstantInt>(D);
|
|
if (!DCst) return nullptr;
|
|
|
|
if (Mask & (FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_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 = BCst->getValue() & DCst->getValue();
|
|
|
|
if (NewMask == BCst->getValue())
|
|
return LHS;
|
|
else if (NewMask == DCst->getValue())
|
|
return RHS;
|
|
}
|
|
if (Mask & FoldMskICmp_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 = BCst->getValue() | DCst->getValue();
|
|
|
|
if (NewMask == BCst->getValue())
|
|
return LHS;
|
|
else if (NewMask == DCst->getValue())
|
|
return RHS;
|
|
}
|
|
if (Mask & FoldMskICmp_BMask_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.
|
|
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
|
|
if (!CCst) return nullptr;
|
|
ConstantInt *ECst = dyn_cast<ConstantInt>(E);
|
|
if (!ECst) return nullptr;
|
|
if (LHSCC != NewCC)
|
|
CCst = cast<ConstantInt>(ConstantExpr::getXor(BCst, CCst));
|
|
if (RHSCC != NewCC)
|
|
ECst = cast<ConstantInt>(ConstantExpr::getXor(DCst, ECst));
|
|
// If there is a conflict, we should actually return a false for the
|
|
// whole construct.
|
|
if (((BCst->getValue() & DCst->getValue()) &
|
|
(CCst->getValue() ^ ECst->getValue())) != 0)
|
|
return ConstantInt::get(LHS->getType(), !IsAnd);
|
|
Value *NewOr1 = Builder->CreateOr(B, D);
|
|
Value *NewOr2 = ConstantExpr::getOr(CCst, ECst);
|
|
Value *NewAnd = Builder->CreateAnd(A, NewOr1);
|
|
return Builder->CreateICmp(NewCC, NewAnd, NewOr2);
|
|
}
|
|
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 *InstCombiner::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<ConstantInt>(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 *RangeEnd;
|
|
if (Cmp1->getOperand(0) == Input) {
|
|
// For the upper range compare we have: icmp x, n
|
|
RangeEnd = Cmp1->getOperand(1);
|
|
} else if (Cmp1->getOperand(1) == Input) {
|
|
// For the upper range compare we have: icmp n, x
|
|
RangeEnd = Cmp1->getOperand(0);
|
|
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.
|
|
bool IsNegative, IsNotNegative;
|
|
ComputeSignBit(RangeEnd, IsNotNegative, IsNegative, /*Depth=*/0, Cmp1);
|
|
if (!IsNotNegative)
|
|
return nullptr;
|
|
|
|
if (Inverted)
|
|
NewPred = ICmpInst::getInversePredicate(NewPred);
|
|
|
|
return Builder->CreateICmp(NewPred, Input, RangeEnd);
|
|
}
|
|
|
|
/// Fold (icmp)&(icmp) if possible.
|
|
Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
|
|
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
|
|
|
|
// (icmp1 A, B) & (icmp2 A, B) --> (icmp3 A, B)
|
|
if (PredicatesFoldable(LHSCC, RHSCC)) {
|
|
if (LHS->getOperand(0) == RHS->getOperand(1) &&
|
|
LHS->getOperand(1) == RHS->getOperand(0))
|
|
LHS->swapOperands();
|
|
if (LHS->getOperand(0) == RHS->getOperand(0) &&
|
|
LHS->getOperand(1) == RHS->getOperand(1)) {
|
|
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
|
|
unsigned Code = getICmpCode(LHS) & getICmpCode(RHS);
|
|
bool isSigned = LHS->isSigned() || RHS->isSigned();
|
|
return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
|
|
}
|
|
}
|
|
|
|
// handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E)
|
|
if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, true, Builder))
|
|
return V;
|
|
|
|
// E.g. (icmp sge x, 0) & (icmp slt x, n) --> icmp ult x, n
|
|
if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/false))
|
|
return V;
|
|
|
|
// E.g. (icmp slt x, n) & (icmp sge x, 0) --> icmp ult x, n
|
|
if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/false))
|
|
return V;
|
|
|
|
// This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
|
|
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
|
|
ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
|
|
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
|
|
if (!LHSCst || !RHSCst) return nullptr;
|
|
|
|
if (LHSCst == RHSCst && LHSCC == RHSCC) {
|
|
// (icmp ult A, C) & (icmp ult B, C) --> (icmp ult (A|B), C)
|
|
// where C is a power of 2 or
|
|
// (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0)
|
|
if ((LHSCC == ICmpInst::ICMP_ULT && LHSCst->getValue().isPowerOf2()) ||
|
|
(LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero())) {
|
|
Value *NewOr = Builder->CreateOr(Val, Val2);
|
|
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
|
|
}
|
|
}
|
|
|
|
// (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 (LHSCC == ICmpInst::ICMP_EQ && LHSCC == RHSCC &&
|
|
LHS->hasOneUse() && RHS->hasOneUse()) {
|
|
Value *V;
|
|
ConstantInt *AndCst, *SmallCst = nullptr, *BigCst = nullptr;
|
|
|
|
// (trunc x) == C1 & (and x, CA) == C2
|
|
// (and x, CA) == C2 & (trunc x) == C1
|
|
if (match(Val2, m_Trunc(m_Value(V))) &&
|
|
match(Val, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
|
|
SmallCst = RHSCst;
|
|
BigCst = LHSCst;
|
|
} else if (match(Val, m_Trunc(m_Value(V))) &&
|
|
match(Val2, m_And(m_Specific(V), m_ConstantInt(AndCst)))) {
|
|
SmallCst = LHSCst;
|
|
BigCst = RHSCst;
|
|
}
|
|
|
|
if (SmallCst && BigCst) {
|
|
unsigned BigBitSize = BigCst->getType()->getBitWidth();
|
|
unsigned SmallBitSize = SmallCst->getType()->getBitWidth();
|
|
|
|
// Check that the low bits are zero.
|
|
APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
|
|
if ((Low & AndCst->getValue()) == 0 && (Low & BigCst->getValue()) == 0) {
|
|
Value *NewAnd = Builder->CreateAnd(V, Low | AndCst->getValue());
|
|
APInt N = SmallCst->getValue().zext(BigBitSize) | BigCst->getValue();
|
|
Value *NewVal = ConstantInt::get(AndCst->getType()->getContext(), N);
|
|
return Builder->CreateICmp(LHSCC, NewAnd, NewVal);
|
|
}
|
|
}
|
|
}
|
|
|
|
// From here on, we only handle:
|
|
// (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
|
|
if (Val != Val2) return nullptr;
|
|
|
|
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
|
|
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
|
|
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
|
|
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
|
|
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
|
|
return nullptr;
|
|
|
|
// We can't fold (ugt x, C) & (sgt x, C2).
|
|
if (!PredicatesFoldable(LHSCC, RHSCC))
|
|
return nullptr;
|
|
|
|
// Ensure that the larger constant is on the RHS.
|
|
bool ShouldSwap;
|
|
if (CmpInst::isSigned(LHSCC) ||
|
|
(ICmpInst::isEquality(LHSCC) &&
|
|
CmpInst::isSigned(RHSCC)))
|
|
ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
|
|
else
|
|
ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
|
|
|
|
if (ShouldSwap) {
|
|
std::swap(LHS, RHS);
|
|
std::swap(LHSCst, RHSCst);
|
|
std::swap(LHSCC, RHSCC);
|
|
}
|
|
|
|
// At this point, we know we have two icmp instructions
|
|
// comparing a value against two constants and and'ing the result
|
|
// together. Because of the above check, we know that we only have
|
|
// icmp eq, icmp ne, icmp [su]lt, and icmp [SU]gt here. We also know
|
|
// (from the icmp folding check above), that the two constants
|
|
// are not equal and that the larger constant is on the RHS
|
|
assert(LHSCst != RHSCst && "Compares not folded above?");
|
|
|
|
switch (LHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_NE: // (X == 13 & X != 15) -> X == 13
|
|
case ICmpInst::ICMP_ULT: // (X == 13 & X < 15) -> X == 13
|
|
case ICmpInst::ICMP_SLT: // (X == 13 & X < 15) -> X == 13
|
|
return LHS;
|
|
}
|
|
case ICmpInst::ICMP_NE:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_ULT:
|
|
if (LHSCst == SubOne(RHSCst)) // (X != 13 & X u< 14) -> X < 13
|
|
return Builder->CreateICmpULT(Val, LHSCst);
|
|
if (LHSCst->isNullValue()) // (X != 0 & X u< 14) -> X-1 u< 13
|
|
return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
|
|
false, true);
|
|
break; // (X != 13 & X u< 15) -> no change
|
|
case ICmpInst::ICMP_SLT:
|
|
if (LHSCst == SubOne(RHSCst)) // (X != 13 & X s< 14) -> X < 13
|
|
return Builder->CreateICmpSLT(Val, LHSCst);
|
|
break; // (X != 13 & X s< 15) -> no change
|
|
case ICmpInst::ICMP_EQ: // (X != 13 & X == 15) -> X == 15
|
|
case ICmpInst::ICMP_UGT: // (X != 13 & X u> 15) -> X u> 15
|
|
case ICmpInst::ICMP_SGT: // (X != 13 & X s> 15) -> X s> 15
|
|
return RHS;
|
|
case ICmpInst::ICMP_NE:
|
|
// Special case to get the ordering right when the values wrap around
|
|
// zero.
|
|
if (LHSCst->getValue() == 0 && RHSCst->getValue().isAllOnesValue())
|
|
std::swap(LHSCst, RHSCst);
|
|
if (LHSCst == SubOne(RHSCst)){// (X != 13 & X != 14) -> X-13 >u 1
|
|
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
|
|
Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
|
|
return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
|
|
Val->getName()+".cmp");
|
|
}
|
|
break; // (X != 13 & X != 15) -> no change
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_ULT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X u< 13 & X == 15) -> false
|
|
case ICmpInst::ICMP_UGT: // (X u< 13 & X u> 15) -> false
|
|
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
|
|
case ICmpInst::ICMP_SGT: // (X u< 13 & X s> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X u< 13 & X != 15) -> X u< 13
|
|
case ICmpInst::ICMP_ULT: // (X u< 13 & X u< 15) -> X u< 13
|
|
return LHS;
|
|
case ICmpInst::ICMP_SLT: // (X u< 13 & X s< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_SLT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_UGT: // (X s< 13 & X u> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X s< 13 & X != 15) -> X < 13
|
|
case ICmpInst::ICMP_SLT: // (X s< 13 & X s< 15) -> X < 13
|
|
return LHS;
|
|
case ICmpInst::ICMP_ULT: // (X s< 13 & X u< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_UGT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X u> 13 & X == 15) -> X == 15
|
|
case ICmpInst::ICMP_UGT: // (X u> 13 & X u> 15) -> X u> 15
|
|
return RHS;
|
|
case ICmpInst::ICMP_SGT: // (X u> 13 & X s> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE:
|
|
if (RHSCst == AddOne(LHSCst)) // (X u> 13 & X != 14) -> X u> 14
|
|
return Builder->CreateICmp(LHSCC, Val, RHSCst);
|
|
break; // (X u> 13 & X != 15) -> no change
|
|
case ICmpInst::ICMP_ULT: // (X u> 13 & X u< 15) -> (X-14) <u 1
|
|
return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
|
|
false, true);
|
|
case ICmpInst::ICMP_SLT: // (X u> 13 & X s< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_SGT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X s> 13 & X == 15) -> X == 15
|
|
case ICmpInst::ICMP_SGT: // (X s> 13 & X s> 15) -> X s> 15
|
|
return RHS;
|
|
case ICmpInst::ICMP_UGT: // (X s> 13 & X u> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE:
|
|
if (RHSCst == AddOne(LHSCst)) // (X s> 13 & X != 14) -> X s> 14
|
|
return Builder->CreateICmp(LHSCC, Val, RHSCst);
|
|
break; // (X s> 13 & X != 15) -> no change
|
|
case ICmpInst::ICMP_SLT: // (X s> 13 & X s< 15) -> (X-14) s< 1
|
|
return insertRangeTest(Val, LHSCst->getValue() + 1, RHSCst->getValue(),
|
|
true, true);
|
|
case ICmpInst::ICMP_ULT: // (X s> 13 & X u< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// Optimize (fcmp)&(fcmp). NOTE: Unlike the rest of instcombine, this returns
|
|
/// a Value which should already be inserted into the function.
|
|
Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
|
|
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
|
|
Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
|
|
FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
|
|
|
|
if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
|
|
// Swap RHS operands to match LHS.
|
|
Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
|
|
std::swap(Op1LHS, Op1RHS);
|
|
}
|
|
|
|
// 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
|
|
if (Op0LHS == Op1LHS && Op0RHS == Op1RHS)
|
|
return getFCmpValue(getFCmpCode(Op0CC) & getFCmpCode(Op1CC), Op0LHS, Op0RHS,
|
|
Builder);
|
|
|
|
if (LHS->getPredicate() == FCmpInst::FCMP_ORD &&
|
|
RHS->getPredicate() == FCmpInst::FCMP_ORD) {
|
|
if (LHS->getOperand(0)->getType() != RHS->getOperand(0)->getType())
|
|
return nullptr;
|
|
|
|
// (fcmp ord x, c) & (fcmp ord y, c) -> (fcmp ord x, y)
|
|
if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
|
|
if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
|
|
// If either of the constants are nans, then the whole thing returns
|
|
// false.
|
|
if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
|
|
return Builder->getFalse();
|
|
return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
|
|
}
|
|
|
|
// Handle vector zeros. This occurs because the canonical form of
|
|
// "fcmp ord x,x" is "fcmp ord x, 0".
|
|
if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
|
|
isa<ConstantAggregateZero>(RHS->getOperand(1)))
|
|
return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
|
|
return nullptr;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// Match De Morgan's Laws:
|
|
/// (~A & ~B) == (~(A | B))
|
|
/// (~A | ~B) == (~(A & B))
|
|
static Instruction *matchDeMorgansLaws(BinaryOperator &I,
|
|
InstCombiner::BuilderTy *Builder) {
|
|
auto 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.
|
|
if (Opcode == Instruction::And)
|
|
Opcode = Instruction::Or;
|
|
else
|
|
Opcode = Instruction::And;
|
|
|
|
Value *Op0 = I.getOperand(0);
|
|
Value *Op1 = I.getOperand(1);
|
|
// TODO: Use pattern matchers instead of dyn_cast.
|
|
if (Value *Op0NotVal = dyn_castNotVal(Op0))
|
|
if (Value *Op1NotVal = dyn_castNotVal(Op1))
|
|
if (Op0->hasOneUse() && Op1->hasOneUse()) {
|
|
Value *LogicOp = Builder->CreateBinOp(Opcode, Op0NotVal, Op1NotVal,
|
|
I.getName() + ".demorgan");
|
|
return BinaryOperator::CreateNot(LogicOp);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
bool InstCombiner::shouldOptimizeCast(CastInst *CI) {
|
|
Value *CastSrc = CI->getOperand(0);
|
|
|
|
// Noop casts and casts of constants should be eliminated trivially.
|
|
if (CI->getSrcTy() == CI->getDestTy() || isa<Constant>(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<CastInst>(CastSrc))
|
|
if (isEliminableCastPair(PrecedingCI, CI))
|
|
return false;
|
|
|
|
// If this is a vector sext from a compare, then we don't want to break the
|
|
// idiom where each element of the extended vector is either zero or all ones.
|
|
if (CI->getOpcode() == Instruction::SExt &&
|
|
isa<CmpInst>(CastSrc) && CI->getDestTy()->isVectorTy())
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
Instruction *InstCombiner::foldCastedBitwiseLogic(BinaryOperator &I) {
|
|
auto LogicOpc = I.getOpcode();
|
|
assert((LogicOpc == Instruction::And || LogicOpc == Instruction::Or ||
|
|
LogicOpc == Instruction::Xor) &&
|
|
"Unexpected opcode for bitwise logic folding");
|
|
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
CastInst *Cast0 = dyn_cast<CastInst>(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 one operand is a bitcast and the other is a constant, move the logic
|
|
// operation ahead of the bitcast. That is, do the logic operation in the
|
|
// original type. This can eliminate useless bitcasts and allow normal
|
|
// combines that would otherwise be impeded by the bitcast. Canonicalization
|
|
// ensures that if there is a constant operand, it will be the second operand.
|
|
Value *BC = nullptr;
|
|
Constant *C = nullptr;
|
|
if ((match(Op0, m_BitCast(m_Value(BC))) && match(Op1, m_Constant(C)))) {
|
|
Value *NewConstant = ConstantExpr::getBitCast(C, SrcTy);
|
|
Value *NewOp = Builder->CreateBinOp(LogicOpc, BC, NewConstant, I.getName());
|
|
return CastInst::CreateBitOrPointerCast(NewOp, DestTy);
|
|
}
|
|
|
|
// Similarly, if one operand is zexted and the other is a constant, move the
|
|
// logic operation ahead of the zext 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(Op0, m_OneUse(m_ZExt(m_Value(X)))) && match(Op1, m_Constant(C))) {
|
|
Constant *TruncC = ConstantExpr::getTrunc(C, SrcTy);
|
|
Constant *ZextTruncC = ConstantExpr::getZExt(TruncC, DestTy);
|
|
if (ZextTruncC == C) {
|
|
// LogicOpc (zext X), C --> zext (LogicOpc X, C)
|
|
Value *NewOp = Builder->CreateBinOp(LogicOpc, X, TruncC);
|
|
return new ZExtInst(NewOp, DestTy);
|
|
}
|
|
}
|
|
|
|
CastInst *Cast1 = dyn_cast<CastInst>(Op1);
|
|
if (!Cast1)
|
|
return nullptr;
|
|
|
|
// Both operands of the logic operation are casts. The casts must be of the
|
|
// same type for reduction.
|
|
auto CastOpcode = Cast0->getOpcode();
|
|
if (CastOpcode != Cast1->getOpcode() || SrcTy != Cast1->getSrcTy())
|
|
return nullptr;
|
|
|
|
Value *Cast0Src = Cast0->getOperand(0);
|
|
Value *Cast1Src = Cast1->getOperand(0);
|
|
|
|
// fold logic(cast(A), cast(B)) -> cast(logic(A, B))
|
|
if (shouldOptimizeCast(Cast0) && shouldOptimizeCast(Cast1)) {
|
|
Value *NewOp = Builder->CreateBinOp(LogicOpc, Cast0Src, Cast1Src,
|
|
I.getName());
|
|
return CastInst::Create(CastOpcode, NewOp, DestTy);
|
|
}
|
|
|
|
// For now, only 'and'/'or' have optimizations after this.
|
|
if (LogicOpc == Instruction::Xor)
|
|
return nullptr;
|
|
|
|
// If this is logic(cast(icmp), cast(icmp)), try to fold this even if the
|
|
// cast is otherwise not optimizable. This happens for vector sexts.
|
|
ICmpInst *ICmp0 = dyn_cast<ICmpInst>(Cast0Src);
|
|
ICmpInst *ICmp1 = dyn_cast<ICmpInst>(Cast1Src);
|
|
if (ICmp0 && ICmp1) {
|
|
Value *Res = LogicOpc == Instruction::And ? FoldAndOfICmps(ICmp0, ICmp1)
|
|
: FoldOrOfICmps(ICmp0, ICmp1, &I);
|
|
if (Res)
|
|
return CastInst::Create(CastOpcode, Res, DestTy);
|
|
return nullptr;
|
|
}
|
|
|
|
// If this is logic(cast(fcmp), cast(fcmp)), try to fold this even if the
|
|
// cast is otherwise not optimizable. This happens for vector sexts.
|
|
FCmpInst *FCmp0 = dyn_cast<FCmpInst>(Cast0Src);
|
|
FCmpInst *FCmp1 = dyn_cast<FCmpInst>(Cast1Src);
|
|
if (FCmp0 && FCmp1) {
|
|
Value *Res = LogicOpc == Instruction::And ? FoldAndOfFCmps(FCmp0, FCmp1)
|
|
: FoldOrOfFCmps(FCmp0, FCmp1);
|
|
if (Res)
|
|
return CastInst::Create(CastOpcode, Res, DestTy);
|
|
return nullptr;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
static Instruction *foldBoolSextMaskToSelect(BinaryOperator &I) {
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
|
|
// Canonicalize SExt or Not to the LHS
|
|
if (match(Op1, m_SExt(m_Value())) || match(Op1, m_Not(m_Value()))) {
|
|
std::swap(Op0, Op1);
|
|
}
|
|
|
|
// Fold (and (sext bool to A), B) --> (select bool, B, 0)
|
|
Value *X = nullptr;
|
|
if (match(Op0, m_SExt(m_Value(X))) &&
|
|
X->getType()->getScalarType()->isIntegerTy(1)) {
|
|
Value *Zero = Constant::getNullValue(Op1->getType());
|
|
return SelectInst::Create(X, Op1, Zero);
|
|
}
|
|
|
|
// Fold (and ~(sext bool to A), B) --> (select bool, 0, B)
|
|
if (match(Op0, m_Not(m_SExt(m_Value(X)))) &&
|
|
X->getType()->getScalarType()->isIntegerTy(1)) {
|
|
Value *Zero = Constant::getNullValue(Op0->getType());
|
|
return SelectInst::Create(X, Zero, Op1);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
|
|
bool Changed = SimplifyAssociativeOrCommutative(I);
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
|
|
if (Value *V = SimplifyVectorOp(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
if (Value *V = SimplifyAndInst(Op0, Op1, DL, &TLI, &DT, &AC))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
// (A|B)&(A|C) -> A|(B&C) etc
|
|
if (Value *V = SimplifyUsingDistributiveLaws(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 (Value *V = SimplifyBSwap(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
|
|
const APInt &AndRHSMask = AndRHS->getValue();
|
|
|
|
// Optimize a variety of ((val OP C1) & C2) combinations...
|
|
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
|
|
Value *Op0LHS = Op0I->getOperand(0);
|
|
Value *Op0RHS = Op0I->getOperand(1);
|
|
switch (Op0I->getOpcode()) {
|
|
default: break;
|
|
case Instruction::Xor:
|
|
case Instruction::Or: {
|
|
// If the mask is only needed on one incoming arm, push it up.
|
|
if (!Op0I->hasOneUse()) break;
|
|
|
|
APInt NotAndRHS(~AndRHSMask);
|
|
if (MaskedValueIsZero(Op0LHS, NotAndRHS, 0, &I)) {
|
|
// Not masking anything out for the LHS, move to RHS.
|
|
Value *NewRHS = Builder->CreateAnd(Op0RHS, AndRHS,
|
|
Op0RHS->getName()+".masked");
|
|
return BinaryOperator::Create(Op0I->getOpcode(), Op0LHS, NewRHS);
|
|
}
|
|
if (!isa<Constant>(Op0RHS) &&
|
|
MaskedValueIsZero(Op0RHS, NotAndRHS, 0, &I)) {
|
|
// Not masking anything out for the RHS, move to LHS.
|
|
Value *NewLHS = Builder->CreateAnd(Op0LHS, AndRHS,
|
|
Op0LHS->getName()+".masked");
|
|
return BinaryOperator::Create(Op0I->getOpcode(), NewLHS, Op0RHS);
|
|
}
|
|
|
|
break;
|
|
}
|
|
case Instruction::Add:
|
|
// ((A & N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == AndRHS.
|
|
// ((A | N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
|
|
// ((A ^ N) + B) & AndRHS -> (A + B) & AndRHS iff N&AndRHS == 0
|
|
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, false, I))
|
|
return BinaryOperator::CreateAnd(V, AndRHS);
|
|
if (Value *V = FoldLogicalPlusAnd(Op0RHS, Op0LHS, AndRHS, false, I))
|
|
return BinaryOperator::CreateAnd(V, AndRHS); // Add commutes
|
|
break;
|
|
|
|
case Instruction::Sub:
|
|
// ((A & N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == AndRHS.
|
|
// ((A | N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
|
|
// ((A ^ N) - B) & AndRHS -> (A - B) & AndRHS iff N&AndRHS == 0
|
|
if (Value *V = FoldLogicalPlusAnd(Op0LHS, Op0RHS, AndRHS, true, I))
|
|
return BinaryOperator::CreateAnd(V, AndRHS);
|
|
|
|
// -x & 1 -> x & 1
|
|
if (AndRHSMask == 1 && match(Op0LHS, m_Zero()))
|
|
return BinaryOperator::CreateAnd(Op0RHS, AndRHS);
|
|
|
|
// (A - N) & AndRHS -> -N & AndRHS iff A&AndRHS==0 and AndRHS
|
|
// has 1's for all bits that the subtraction with A might affect.
|
|
if (Op0I->hasOneUse() && !match(Op0LHS, m_Zero())) {
|
|
uint32_t BitWidth = AndRHSMask.getBitWidth();
|
|
uint32_t Zeros = AndRHSMask.countLeadingZeros();
|
|
APInt Mask = APInt::getLowBitsSet(BitWidth, BitWidth - Zeros);
|
|
|
|
if (MaskedValueIsZero(Op0LHS, Mask, 0, &I)) {
|
|
Value *NewNeg = Builder->CreateNeg(Op0RHS);
|
|
return BinaryOperator::CreateAnd(NewNeg, AndRHS);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case Instruction::Shl:
|
|
case Instruction::LShr:
|
|
// (1 << x) & 1 --> zext(x == 0)
|
|
// (1 >> x) & 1 --> zext(x == 0)
|
|
if (AndRHSMask == 1 && Op0LHS == AndRHS) {
|
|
Value *NewICmp =
|
|
Builder->CreateICmpEQ(Op0RHS, Constant::getNullValue(I.getType()));
|
|
return new ZExtInst(NewICmp, I.getType());
|
|
}
|
|
break;
|
|
}
|
|
|
|
if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1)))
|
|
if (Instruction *Res = OptAndOp(Op0I, Op0CI, AndRHS, I))
|
|
return Res;
|
|
}
|
|
|
|
// If this is an integer truncation, and if the source is an 'and' with
|
|
// immediate, transform it. This frequently occurs for bitfield accesses.
|
|
{
|
|
Value *X = nullptr; ConstantInt *YC = nullptr;
|
|
if (match(Op0, m_Trunc(m_And(m_Value(X), m_ConstantInt(YC))))) {
|
|
// Change: and (trunc (and X, YC) to T), C2
|
|
// into : and (trunc X to T), trunc(YC) & C2
|
|
// This will fold the two constants together, which may allow
|
|
// other simplifications.
|
|
Value *NewCast = Builder->CreateTrunc(X, I.getType(), "and.shrunk");
|
|
Constant *C3 = ConstantExpr::getTrunc(YC, I.getType());
|
|
C3 = ConstantExpr::getAnd(C3, AndRHS);
|
|
return BinaryOperator::CreateAnd(NewCast, C3);
|
|
}
|
|
}
|
|
|
|
// Try to fold constant and into select arguments.
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
|
|
if (Instruction *R = FoldOpIntoSelect(I, SI))
|
|
return R;
|
|
if (isa<PHINode>(Op0))
|
|
if (Instruction *NV = FoldOpIntoPhi(I))
|
|
return NV;
|
|
}
|
|
|
|
if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
|
|
return DeMorgan;
|
|
|
|
{
|
|
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
|
|
// (A|B) & ~(A&B) -> A^B
|
|
if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
|
|
match(Op1, m_Not(m_And(m_Value(C), m_Value(D)))) &&
|
|
((A == C && B == D) || (A == D && B == C)))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
|
|
// ~(A&B) & (A|B) -> A^B
|
|
if (match(Op1, m_Or(m_Value(A), m_Value(B))) &&
|
|
match(Op0, m_Not(m_And(m_Value(C), m_Value(D)))) &&
|
|
((A == C && B == D) || (A == D && B == C)))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
|
|
// A&(A^B) => A & ~B
|
|
{
|
|
Value *tmpOp0 = Op0;
|
|
Value *tmpOp1 = Op1;
|
|
if (match(Op0, m_OneUse(m_Xor(m_Value(A), m_Value(B))))) {
|
|
if (A == Op1 || B == Op1 ) {
|
|
tmpOp1 = Op0;
|
|
tmpOp0 = Op1;
|
|
// Simplify below
|
|
}
|
|
}
|
|
|
|
if (match(tmpOp1, m_OneUse(m_Xor(m_Value(A), m_Value(B))))) {
|
|
if (B == tmpOp0) {
|
|
std::swap(A, B);
|
|
}
|
|
// Notice that the pattern (A&(~B)) is actually (A&(-1^B)), so if
|
|
// A is originally -1 (or a vector of -1 and undefs), then we enter
|
|
// an endless loop. By checking that A is non-constant we ensure that
|
|
// we will never get to the loop.
|
|
if (A == tmpOp0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B
|
|
return BinaryOperator::CreateAnd(A, Builder->CreateNot(B));
|
|
}
|
|
}
|
|
|
|
// (A&((~A)|B)) -> A&B
|
|
if (match(Op0, m_Or(m_Not(m_Specific(Op1)), m_Value(A))) ||
|
|
match(Op0, m_Or(m_Value(A), m_Not(m_Specific(Op1)))))
|
|
return BinaryOperator::CreateAnd(A, Op1);
|
|
if (match(Op1, m_Or(m_Not(m_Specific(Op0)), m_Value(A))) ||
|
|
match(Op1, m_Or(m_Value(A), m_Not(m_Specific(Op0)))))
|
|
return BinaryOperator::CreateAnd(A, Op0);
|
|
|
|
// (A ^ B) & ((B ^ C) ^ A) -> (A ^ B) & ~C
|
|
if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
|
|
if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
|
|
if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
|
|
return BinaryOperator::CreateAnd(Op0, Builder->CreateNot(C));
|
|
|
|
// ((A ^ C) ^ B) & (B ^ A) -> (B ^ A) & ~C
|
|
if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
|
|
if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
|
|
if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
|
|
return BinaryOperator::CreateAnd(Op1, Builder->CreateNot(C));
|
|
|
|
// (A | B) & ((~A) ^ B) -> (A & B)
|
|
if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
|
|
match(Op1, m_Xor(m_Not(m_Specific(A)), m_Specific(B))))
|
|
return BinaryOperator::CreateAnd(A, B);
|
|
|
|
// ((~A) ^ B) & (A | B) -> (A & B)
|
|
if (match(Op0, m_Xor(m_Not(m_Value(A)), m_Value(B))) &&
|
|
match(Op1, m_Or(m_Specific(A), m_Specific(B))))
|
|
return BinaryOperator::CreateAnd(A, B);
|
|
}
|
|
|
|
{
|
|
ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
|
|
ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
|
|
if (LHS && RHS)
|
|
if (Value *Res = FoldAndOfICmps(LHS, RHS))
|
|
return replaceInstUsesWith(I, Res);
|
|
|
|
// TODO: Make this recursive; it's a little tricky because an arbitrary
|
|
// number of 'and' instructions might have to be created.
|
|
Value *X, *Y;
|
|
if (LHS && match(Op1, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(X))
|
|
if (Value *Res = FoldAndOfICmps(LHS, Cmp))
|
|
return replaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
|
|
if (Value *Res = FoldAndOfICmps(LHS, Cmp))
|
|
return replaceInstUsesWith(I, Builder->CreateAnd(Res, X));
|
|
}
|
|
if (RHS && match(Op0, m_OneUse(m_And(m_Value(X), m_Value(Y))))) {
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(X))
|
|
if (Value *Res = FoldAndOfICmps(Cmp, RHS))
|
|
return replaceInstUsesWith(I, Builder->CreateAnd(Res, Y));
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
|
|
if (Value *Res = FoldAndOfICmps(Cmp, RHS))
|
|
return replaceInstUsesWith(I, Builder->CreateAnd(Res, X));
|
|
}
|
|
}
|
|
|
|
// If and'ing two fcmp, try combine them into one.
|
|
if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
|
|
if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
|
|
if (Value *Res = FoldAndOfFCmps(LHS, RHS))
|
|
return replaceInstUsesWith(I, Res);
|
|
|
|
if (Instruction *CastedAnd = foldCastedBitwiseLogic(I))
|
|
return CastedAnd;
|
|
|
|
if (Instruction *Select = foldBoolSextMaskToSelect(I))
|
|
return Select;
|
|
|
|
return Changed ? &I : nullptr;
|
|
}
|
|
|
|
/// Given an OR instruction, check to see if this is a bswap idiom. If so,
|
|
/// insert the new intrinsic and return it.
|
|
Instruction *InstCombiner::MatchBSwap(BinaryOperator &I) {
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
|
|
// Look through zero extends.
|
|
if (Instruction *Ext = dyn_cast<ZExtInst>(Op0))
|
|
Op0 = Ext->getOperand(0);
|
|
|
|
if (Instruction *Ext = dyn_cast<ZExtInst>(Op1))
|
|
Op1 = Ext->getOperand(0);
|
|
|
|
// (A | B) | C and A | (B | C) -> bswap if possible.
|
|
bool OrOfOrs = match(Op0, m_Or(m_Value(), m_Value())) ||
|
|
match(Op1, m_Or(m_Value(), m_Value()));
|
|
|
|
// (A >> B) | (C << D) and (A << B) | (B >> C) -> bswap if possible.
|
|
bool OrOfShifts = match(Op0, m_LogicalShift(m_Value(), m_Value())) &&
|
|
match(Op1, m_LogicalShift(m_Value(), m_Value()));
|
|
|
|
// (A & B) | (C & D) -> bswap if possible.
|
|
bool OrOfAnds = match(Op0, m_And(m_Value(), m_Value())) &&
|
|
match(Op1, m_And(m_Value(), m_Value()));
|
|
|
|
if (!OrOfOrs && !OrOfShifts && !OrOfAnds)
|
|
return nullptr;
|
|
|
|
SmallVector<Instruction*, 4> Insts;
|
|
if (!recognizeBSwapOrBitReverseIdiom(&I, true, false, Insts))
|
|
return nullptr;
|
|
Instruction *LastInst = Insts.pop_back_val();
|
|
LastInst->removeFromParent();
|
|
|
|
for (auto *Inst : Insts)
|
|
Worklist.Add(Inst);
|
|
return LastInst;
|
|
}
|
|
|
|
/// If all elements of two constant vectors are 0/-1 and inverses, return true.
|
|
static bool areInverseVectorBitmasks(Constant *C1, Constant *C2) {
|
|
unsigned NumElts = C1->getType()->getVectorNumElements();
|
|
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.
|
|
// FIXME: Allow undef elements.
|
|
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.
|
|
static Value *getSelectCondition(Value *A, Value *B,
|
|
InstCombiner::BuilderTy &Builder) {
|
|
// If these are scalars or vectors of i1, A can be used directly.
|
|
Type *Ty = A->getType();
|
|
if (match(A, m_Not(m_Specific(B))) && Ty->getScalarType()->isIntegerTy(1))
|
|
return A;
|
|
|
|
// If A and B are sign-extended, look through the sexts to find the booleans.
|
|
Value *Cond;
|
|
if (match(A, m_SExt(m_Value(Cond))) &&
|
|
Cond->getType()->getScalarType()->isIntegerTy(1) &&
|
|
match(B, m_CombineOr(m_Not(m_SExt(m_Specific(Cond))),
|
|
m_SExt(m_Not(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 constants, see if the constants are inverse bitmasks.
|
|
Constant *AC, *BC;
|
|
if (match(A, m_Constant(AC)) && match(B, m_Constant(BC)) &&
|
|
areInverseVectorBitmasks(AC, BC))
|
|
return ConstantExpr::getTrunc(AC, CmpInst::makeCmpResultType(Ty));
|
|
|
|
// If both operands are xor'd with constants using the same sexted boolean
|
|
// operand, see if the constants are inverse bitmasks.
|
|
if (match(A, (m_Xor(m_SExt(m_Value(Cond)), m_Constant(AC)))) &&
|
|
match(B, (m_Xor(m_SExt(m_Specific(Cond)), m_Constant(BC)))) &&
|
|
Cond->getType()->getScalarType()->isIntegerTy(1) &&
|
|
areInverseVectorBitmasks(AC, BC)) {
|
|
AC = ConstantExpr::getTrunc(AC, CmpInst::makeCmpResultType(Ty));
|
|
return Builder.CreateXor(Cond, AC);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
/// We have an expression of the form (A & C) | (B & D). Try to simplify this
|
|
/// to "A' ? C : D", where A' is a boolean or vector of booleans.
|
|
static Value *matchSelectFromAndOr(Value *A, Value *C, Value *B, Value *D,
|
|
InstCombiner::BuilderTy &Builder) {
|
|
// 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();
|
|
Value *SrcA, *SrcB;
|
|
if (match(A, m_OneUse(m_BitCast(m_Value(SrcA)))) &&
|
|
match(B, m_OneUse(m_BitCast(m_Value(SrcB))))) {
|
|
A = SrcA;
|
|
B = SrcB;
|
|
}
|
|
|
|
if (Value *Cond = getSelectCondition(A, B, Builder)) {
|
|
// ((bc Cond) & C) | ((bc ~Cond) & D) --> bc (select Cond, (bc C), (bc D))
|
|
// The bitcasts will either all exist or all not exist. The builder will
|
|
// not create unnecessary casts if the types already match.
|
|
Value *BitcastC = Builder.CreateBitCast(C, A->getType());
|
|
Value *BitcastD = Builder.CreateBitCast(D, A->getType());
|
|
Value *Select = Builder.CreateSelect(Cond, BitcastC, BitcastD);
|
|
return Builder.CreateBitCast(Select, OrigType);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// Fold (icmp)|(icmp) if possible.
|
|
Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS,
|
|
Instruction *CxtI) {
|
|
ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
|
|
|
|
// Fold (iszero(A & K1) | iszero(A & K2)) -> (A & (K1 | K2)) != (K1 | K2)
|
|
// if K1 and K2 are a one-bit mask.
|
|
ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
|
|
ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
|
|
|
|
if (LHS->getPredicate() == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero() &&
|
|
RHS->getPredicate() == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
|
|
|
|
BinaryOperator *LAnd = dyn_cast<BinaryOperator>(LHS->getOperand(0));
|
|
BinaryOperator *RAnd = dyn_cast<BinaryOperator>(RHS->getOperand(0));
|
|
if (LAnd && RAnd && LAnd->hasOneUse() && RHS->hasOneUse() &&
|
|
LAnd->getOpcode() == Instruction::And &&
|
|
RAnd->getOpcode() == Instruction::And) {
|
|
|
|
Value *Mask = nullptr;
|
|
Value *Masked = nullptr;
|
|
if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
|
|
isKnownToBeAPowerOfTwo(LAnd->getOperand(1), DL, false, 0, &AC, CxtI,
|
|
&DT) &&
|
|
isKnownToBeAPowerOfTwo(RAnd->getOperand(1), DL, false, 0, &AC, CxtI,
|
|
&DT)) {
|
|
Mask = Builder->CreateOr(LAnd->getOperand(1), RAnd->getOperand(1));
|
|
Masked = Builder->CreateAnd(LAnd->getOperand(0), Mask);
|
|
} else if (LAnd->getOperand(1) == RAnd->getOperand(1) &&
|
|
isKnownToBeAPowerOfTwo(LAnd->getOperand(0), DL, false, 0, &AC,
|
|
CxtI, &DT) &&
|
|
isKnownToBeAPowerOfTwo(RAnd->getOperand(0), DL, false, 0, &AC,
|
|
CxtI, &DT)) {
|
|
Mask = Builder->CreateOr(LAnd->getOperand(0), RAnd->getOperand(0));
|
|
Masked = Builder->CreateAnd(LAnd->getOperand(1), Mask);
|
|
}
|
|
|
|
if (Masked)
|
|
return Builder->CreateICmp(ICmpInst::ICMP_NE, Masked, Mask);
|
|
}
|
|
}
|
|
|
|
// Fold (icmp ult/ule (A + C1), C3) | (icmp ult/ule (A + C2), C3)
|
|
// --> (icmp ult/ule ((A & ~(C1 ^ C2)) + max(C1, C2)), C3)
|
|
// The original condition actually refers to the following two ranges:
|
|
// [MAX_UINT-C1+1, MAX_UINT-C1+1+C3] and [MAX_UINT-C2+1, MAX_UINT-C2+1+C3]
|
|
// We can fold these two ranges if:
|
|
// 1) C1 and C2 is unsigned greater than C3.
|
|
// 2) The two ranges are separated.
|
|
// 3) C1 ^ C2 is one-bit mask.
|
|
// 4) LowRange1 ^ LowRange2 and HighRange1 ^ HighRange2 are one-bit mask.
|
|
// This implies all values in the two ranges differ by exactly one bit.
|
|
|
|
if ((LHSCC == ICmpInst::ICMP_ULT || LHSCC == ICmpInst::ICMP_ULE) &&
|
|
LHSCC == RHSCC && LHSCst && RHSCst && LHS->hasOneUse() &&
|
|
RHS->hasOneUse() && LHSCst->getType() == RHSCst->getType() &&
|
|
LHSCst->getValue() == (RHSCst->getValue())) {
|
|
|
|
Value *LAdd = LHS->getOperand(0);
|
|
Value *RAdd = RHS->getOperand(0);
|
|
|
|
Value *LAddOpnd, *RAddOpnd;
|
|
ConstantInt *LAddCst, *RAddCst;
|
|
if (match(LAdd, m_Add(m_Value(LAddOpnd), m_ConstantInt(LAddCst))) &&
|
|
match(RAdd, m_Add(m_Value(RAddOpnd), m_ConstantInt(RAddCst))) &&
|
|
LAddCst->getValue().ugt(LHSCst->getValue()) &&
|
|
RAddCst->getValue().ugt(LHSCst->getValue())) {
|
|
|
|
APInt DiffCst = LAddCst->getValue() ^ RAddCst->getValue();
|
|
if (LAddOpnd == RAddOpnd && DiffCst.isPowerOf2()) {
|
|
ConstantInt *MaxAddCst = nullptr;
|
|
if (LAddCst->getValue().ult(RAddCst->getValue()))
|
|
MaxAddCst = RAddCst;
|
|
else
|
|
MaxAddCst = LAddCst;
|
|
|
|
APInt RRangeLow = -RAddCst->getValue();
|
|
APInt RRangeHigh = RRangeLow + LHSCst->getValue();
|
|
APInt LRangeLow = -LAddCst->getValue();
|
|
APInt LRangeHigh = LRangeLow + LHSCst->getValue();
|
|
APInt LowRangeDiff = RRangeLow ^ LRangeLow;
|
|
APInt HighRangeDiff = RRangeHigh ^ LRangeHigh;
|
|
APInt RangeDiff = LRangeLow.sgt(RRangeLow) ? LRangeLow - RRangeLow
|
|
: RRangeLow - LRangeLow;
|
|
|
|
if (LowRangeDiff.isPowerOf2() && LowRangeDiff == HighRangeDiff &&
|
|
RangeDiff.ugt(LHSCst->getValue())) {
|
|
Value *MaskCst = ConstantInt::get(LAddCst->getType(), ~DiffCst);
|
|
|
|
Value *NewAnd = Builder->CreateAnd(LAddOpnd, MaskCst);
|
|
Value *NewAdd = Builder->CreateAdd(NewAnd, MaxAddCst);
|
|
return (Builder->CreateICmp(LHS->getPredicate(), NewAdd, LHSCst));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
|
|
if (PredicatesFoldable(LHSCC, RHSCC)) {
|
|
if (LHS->getOperand(0) == RHS->getOperand(1) &&
|
|
LHS->getOperand(1) == RHS->getOperand(0))
|
|
LHS->swapOperands();
|
|
if (LHS->getOperand(0) == RHS->getOperand(0) &&
|
|
LHS->getOperand(1) == RHS->getOperand(1)) {
|
|
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
|
|
unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
|
|
bool isSigned = LHS->isSigned() || RHS->isSigned();
|
|
return getNewICmpValue(isSigned, Code, Op0, Op1, Builder);
|
|
}
|
|
}
|
|
|
|
// handle (roughly):
|
|
// (icmp ne (A & B), C) | (icmp ne (A & D), E)
|
|
if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
|
|
return V;
|
|
|
|
Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
|
|
if (LHS->hasOneUse() || RHS->hasOneUse()) {
|
|
// (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
|
|
// (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
|
|
Value *A = nullptr, *B = nullptr;
|
|
if (LHSCC == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero()) {
|
|
B = Val;
|
|
if (RHSCC == ICmpInst::ICMP_ULT && Val == RHS->getOperand(1))
|
|
A = Val2;
|
|
else if (RHSCC == ICmpInst::ICMP_UGT && Val == Val2)
|
|
A = RHS->getOperand(1);
|
|
}
|
|
// (icmp ult A, B) | (icmp eq B, 0) -> (icmp ule A, B-1)
|
|
// (icmp ugt B, A) | (icmp eq B, 0) -> (icmp ule A, B-1)
|
|
else if (RHSCC == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
|
|
B = Val2;
|
|
if (LHSCC == ICmpInst::ICMP_ULT && Val2 == LHS->getOperand(1))
|
|
A = Val;
|
|
else if (LHSCC == ICmpInst::ICMP_UGT && Val2 == Val)
|
|
A = LHS->getOperand(1);
|
|
}
|
|
if (A && B)
|
|
return Builder->CreateICmp(
|
|
ICmpInst::ICMP_UGE,
|
|
Builder->CreateAdd(B, ConstantInt::getSigned(B->getType(), -1)), A);
|
|
}
|
|
|
|
// E.g. (icmp slt x, 0) | (icmp sgt x, n) --> icmp ugt x, n
|
|
if (Value *V = simplifyRangeCheck(LHS, RHS, /*Inverted=*/true))
|
|
return V;
|
|
|
|
// E.g. (icmp sgt x, n) | (icmp slt x, 0) --> icmp ugt x, n
|
|
if (Value *V = simplifyRangeCheck(RHS, LHS, /*Inverted=*/true))
|
|
return V;
|
|
|
|
// This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
|
|
if (!LHSCst || !RHSCst) return nullptr;
|
|
|
|
if (LHSCst == RHSCst && LHSCC == RHSCC) {
|
|
// (icmp ne A, 0) | (icmp ne B, 0) --> (icmp ne (A|B), 0)
|
|
if (LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero()) {
|
|
Value *NewOr = Builder->CreateOr(Val, Val2);
|
|
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
|
|
}
|
|
}
|
|
|
|
// (icmp ult (X + CA), C1) | (icmp eq X, C2) -> (icmp ule (X + CA), C1)
|
|
// iff C2 + CA == C1.
|
|
if (LHSCC == ICmpInst::ICMP_ULT && RHSCC == ICmpInst::ICMP_EQ) {
|
|
ConstantInt *AddCst;
|
|
if (match(Val, m_Add(m_Specific(Val2), m_ConstantInt(AddCst))))
|
|
if (RHSCst->getValue() + AddCst->getValue() == LHSCst->getValue())
|
|
return Builder->CreateICmpULE(Val, LHSCst);
|
|
}
|
|
|
|
// From here on, we only handle:
|
|
// (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
|
|
if (Val != Val2) return nullptr;
|
|
|
|
// ICMP_[US][GL]E X, CST is folded to ICMP_[US][GL]T elsewhere.
|
|
if (LHSCC == ICmpInst::ICMP_UGE || LHSCC == ICmpInst::ICMP_ULE ||
|
|
RHSCC == ICmpInst::ICMP_UGE || RHSCC == ICmpInst::ICMP_ULE ||
|
|
LHSCC == ICmpInst::ICMP_SGE || LHSCC == ICmpInst::ICMP_SLE ||
|
|
RHSCC == ICmpInst::ICMP_SGE || RHSCC == ICmpInst::ICMP_SLE)
|
|
return nullptr;
|
|
|
|
// We can't fold (ugt x, C) | (sgt x, C2).
|
|
if (!PredicatesFoldable(LHSCC, RHSCC))
|
|
return nullptr;
|
|
|
|
// Ensure that the larger constant is on the RHS.
|
|
bool ShouldSwap;
|
|
if (CmpInst::isSigned(LHSCC) ||
|
|
(ICmpInst::isEquality(LHSCC) &&
|
|
CmpInst::isSigned(RHSCC)))
|
|
ShouldSwap = LHSCst->getValue().sgt(RHSCst->getValue());
|
|
else
|
|
ShouldSwap = LHSCst->getValue().ugt(RHSCst->getValue());
|
|
|
|
if (ShouldSwap) {
|
|
std::swap(LHS, RHS);
|
|
std::swap(LHSCst, RHSCst);
|
|
std::swap(LHSCC, RHSCC);
|
|
}
|
|
|
|
// At this point, we know we have two icmp instructions
|
|
// comparing a value against two constants and or'ing the result
|
|
// together. Because of the above check, we know that we only have
|
|
// ICMP_EQ, ICMP_NE, ICMP_LT, and ICMP_GT here. We also know (from the
|
|
// icmp folding check above), that the two constants are not
|
|
// equal.
|
|
assert(LHSCst != RHSCst && "Compares not folded above?");
|
|
|
|
switch (LHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ:
|
|
if (LHS->getOperand(0) == RHS->getOperand(0)) {
|
|
// if LHSCst and RHSCst differ only by one bit:
|
|
// (A == C1 || A == C2) -> (A | (C1 ^ C2)) == C2
|
|
assert(LHSCst->getValue().ule(LHSCst->getValue()));
|
|
|
|
APInt Xor = LHSCst->getValue() ^ RHSCst->getValue();
|
|
if (Xor.isPowerOf2()) {
|
|
Value *Cst = Builder->getInt(Xor);
|
|
Value *Or = Builder->CreateOr(LHS->getOperand(0), Cst);
|
|
return Builder->CreateICmp(ICmpInst::ICMP_EQ, Or, RHSCst);
|
|
}
|
|
}
|
|
|
|
if (LHSCst == SubOne(RHSCst)) {
|
|
// (X == 13 | X == 14) -> X-13 <u 2
|
|
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
|
|
Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
|
|
AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst);
|
|
return Builder->CreateICmpULT(Add, AddCST);
|
|
}
|
|
|
|
break; // (X == 13 | X == 15) -> no change
|
|
case ICmpInst::ICMP_UGT: // (X == 13 | X u> 14) -> no change
|
|
case ICmpInst::ICMP_SGT: // (X == 13 | X s> 14) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X == 13 | X != 15) -> X != 15
|
|
case ICmpInst::ICMP_ULT: // (X == 13 | X u< 15) -> X u< 15
|
|
case ICmpInst::ICMP_SLT: // (X == 13 | X s< 15) -> X s< 15
|
|
return RHS;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_NE:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X != 13 | X == 15) -> X != 13
|
|
case ICmpInst::ICMP_UGT: // (X != 13 | X u> 15) -> X != 13
|
|
case ICmpInst::ICMP_SGT: // (X != 13 | X s> 15) -> X != 13
|
|
return LHS;
|
|
case ICmpInst::ICMP_NE: // (X != 13 | X != 15) -> true
|
|
case ICmpInst::ICMP_ULT: // (X != 13 | X u< 15) -> true
|
|
case ICmpInst::ICMP_SLT: // (X != 13 | X s< 15) -> true
|
|
return Builder->getTrue();
|
|
}
|
|
case ICmpInst::ICMP_ULT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X u< 13 | X == 14) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_UGT: // (X u< 13 | X u> 15) -> (X-13) u> 2
|
|
// If RHSCst is [us]MAXINT, it is always false. Not handling
|
|
// this can cause overflow.
|
|
if (RHSCst->isMaxValue(false))
|
|
return LHS;
|
|
return insertRangeTest(Val, LHSCst->getValue(), RHSCst->getValue() + 1,
|
|
false, false);
|
|
case ICmpInst::ICMP_SGT: // (X u< 13 | X s> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X u< 13 | X != 15) -> X != 15
|
|
case ICmpInst::ICMP_ULT: // (X u< 13 | X u< 15) -> X u< 15
|
|
return RHS;
|
|
case ICmpInst::ICMP_SLT: // (X u< 13 | X s< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_SLT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X s< 13 | X == 14) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_SGT: // (X s< 13 | X s> 15) -> (X-13) s> 2
|
|
// If RHSCst is [us]MAXINT, it is always false. Not handling
|
|
// this can cause overflow.
|
|
if (RHSCst->isMaxValue(true))
|
|
return LHS;
|
|
return insertRangeTest(Val, LHSCst->getValue(), RHSCst->getValue() + 1,
|
|
true, false);
|
|
case ICmpInst::ICMP_UGT: // (X s< 13 | X u> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X s< 13 | X != 15) -> X != 15
|
|
case ICmpInst::ICMP_SLT: // (X s< 13 | X s< 15) -> X s< 15
|
|
return RHS;
|
|
case ICmpInst::ICMP_ULT: // (X s< 13 | X u< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_UGT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X u> 13 | X == 15) -> X u> 13
|
|
case ICmpInst::ICMP_UGT: // (X u> 13 | X u> 15) -> X u> 13
|
|
return LHS;
|
|
case ICmpInst::ICMP_SGT: // (X u> 13 | X s> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X u> 13 | X != 15) -> true
|
|
case ICmpInst::ICMP_ULT: // (X u> 13 | X u< 15) -> true
|
|
return Builder->getTrue();
|
|
case ICmpInst::ICMP_SLT: // (X u> 13 | X s< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
case ICmpInst::ICMP_SGT:
|
|
switch (RHSCC) {
|
|
default: llvm_unreachable("Unknown integer condition code!");
|
|
case ICmpInst::ICMP_EQ: // (X s> 13 | X == 15) -> X > 13
|
|
case ICmpInst::ICMP_SGT: // (X s> 13 | X s> 15) -> X > 13
|
|
return LHS;
|
|
case ICmpInst::ICMP_UGT: // (X s> 13 | X u> 15) -> no change
|
|
break;
|
|
case ICmpInst::ICMP_NE: // (X s> 13 | X != 15) -> true
|
|
case ICmpInst::ICMP_SLT: // (X s> 13 | X s< 15) -> true
|
|
return Builder->getTrue();
|
|
case ICmpInst::ICMP_ULT: // (X s> 13 | X u< 15) -> no change
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
/// Optimize (fcmp)|(fcmp). NOTE: Unlike the rest of instcombine, this returns
|
|
/// a Value which should already be inserted into the function.
|
|
Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
|
|
Value *Op0LHS = LHS->getOperand(0), *Op0RHS = LHS->getOperand(1);
|
|
Value *Op1LHS = RHS->getOperand(0), *Op1RHS = RHS->getOperand(1);
|
|
FCmpInst::Predicate Op0CC = LHS->getPredicate(), Op1CC = RHS->getPredicate();
|
|
|
|
if (Op0LHS == Op1RHS && Op0RHS == Op1LHS) {
|
|
// Swap RHS operands to match LHS.
|
|
Op1CC = FCmpInst::getSwappedPredicate(Op1CC);
|
|
std::swap(Op1LHS, Op1RHS);
|
|
}
|
|
|
|
// Simplify (fcmp cc0 x, y) | (fcmp cc1 x, y).
|
|
// This is a similar transformation to the one in FoldAndOfFCmps.
|
|
//
|
|
// 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 (Op0LHS == Op1LHS && Op0RHS == Op1RHS)
|
|
return getFCmpValue(getFCmpCode(Op0CC) | getFCmpCode(Op1CC), Op0LHS, Op0RHS,
|
|
Builder);
|
|
|
|
if (LHS->getPredicate() == FCmpInst::FCMP_UNO &&
|
|
RHS->getPredicate() == FCmpInst::FCMP_UNO &&
|
|
LHS->getOperand(0)->getType() == RHS->getOperand(0)->getType()) {
|
|
if (ConstantFP *LHSC = dyn_cast<ConstantFP>(LHS->getOperand(1)))
|
|
if (ConstantFP *RHSC = dyn_cast<ConstantFP>(RHS->getOperand(1))) {
|
|
// If either of the constants are nans, then the whole thing returns
|
|
// true.
|
|
if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
|
|
return Builder->getTrue();
|
|
|
|
// Otherwise, no need to compare the two constants, compare the
|
|
// rest.
|
|
return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
|
|
}
|
|
|
|
// Handle vector zeros. This occurs because the canonical form of
|
|
// "fcmp uno x,x" is "fcmp uno x, 0".
|
|
if (isa<ConstantAggregateZero>(LHS->getOperand(1)) &&
|
|
isa<ConstantAggregateZero>(RHS->getOperand(1)))
|
|
return Builder->CreateFCmpUNO(LHS->getOperand(0), RHS->getOperand(0));
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// This helper function folds:
|
|
///
|
|
/// ((A | B) & C1) | (B & C2)
|
|
///
|
|
/// into:
|
|
///
|
|
/// (A & C1) | B
|
|
///
|
|
/// when the XOR of the two constants is "all ones" (-1).
|
|
Instruction *InstCombiner::FoldOrWithConstants(BinaryOperator &I, Value *Op,
|
|
Value *A, Value *B, Value *C) {
|
|
ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
|
|
if (!CI1) return nullptr;
|
|
|
|
Value *V1 = nullptr;
|
|
ConstantInt *CI2 = nullptr;
|
|
if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return nullptr;
|
|
|
|
APInt Xor = CI1->getValue() ^ CI2->getValue();
|
|
if (!Xor.isAllOnesValue()) return nullptr;
|
|
|
|
if (V1 == A || V1 == B) {
|
|
Value *NewOp = Builder->CreateAnd((V1 == A) ? B : A, CI1);
|
|
return BinaryOperator::CreateOr(NewOp, V1);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
/// \brief This helper function folds:
|
|
///
|
|
/// ((A | B) & C1) ^ (B & C2)
|
|
///
|
|
/// into:
|
|
///
|
|
/// (A & C1) ^ B
|
|
///
|
|
/// when the XOR of the two constants is "all ones" (-1).
|
|
Instruction *InstCombiner::FoldXorWithConstants(BinaryOperator &I, Value *Op,
|
|
Value *A, Value *B, Value *C) {
|
|
ConstantInt *CI1 = dyn_cast<ConstantInt>(C);
|
|
if (!CI1)
|
|
return nullptr;
|
|
|
|
Value *V1 = nullptr;
|
|
ConstantInt *CI2 = nullptr;
|
|
if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2))))
|
|
return nullptr;
|
|
|
|
APInt Xor = CI1->getValue() ^ CI2->getValue();
|
|
if (!Xor.isAllOnesValue())
|
|
return nullptr;
|
|
|
|
if (V1 == A || V1 == B) {
|
|
Value *NewOp = Builder->CreateAnd(V1 == A ? B : A, CI1);
|
|
return BinaryOperator::CreateXor(NewOp, V1);
|
|
}
|
|
|
|
return nullptr;
|
|
}
|
|
|
|
Instruction *InstCombiner::visitOr(BinaryOperator &I) {
|
|
bool Changed = SimplifyAssociativeOrCommutative(I);
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
|
|
if (Value *V = SimplifyVectorOp(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
if (Value *V = SimplifyOrInst(Op0, Op1, DL, &TLI, &DT, &AC))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
// (A&B)|(A&C) -> A&(B|C) etc
|
|
if (Value *V = SimplifyUsingDistributiveLaws(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 (Value *V = SimplifyBSwap(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
|
|
ConstantInt *C1 = nullptr; Value *X = nullptr;
|
|
// (X & C1) | C2 --> (X | C2) & (C1|C2)
|
|
// iff (C1 & C2) == 0.
|
|
if (match(Op0, m_And(m_Value(X), m_ConstantInt(C1))) &&
|
|
(RHS->getValue() & C1->getValue()) != 0 &&
|
|
Op0->hasOneUse()) {
|
|
Value *Or = Builder->CreateOr(X, RHS);
|
|
Or->takeName(Op0);
|
|
return BinaryOperator::CreateAnd(Or,
|
|
Builder->getInt(RHS->getValue() | C1->getValue()));
|
|
}
|
|
|
|
// (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
|
|
if (match(Op0, m_Xor(m_Value(X), m_ConstantInt(C1))) &&
|
|
Op0->hasOneUse()) {
|
|
Value *Or = Builder->CreateOr(X, RHS);
|
|
Or->takeName(Op0);
|
|
return BinaryOperator::CreateXor(Or,
|
|
Builder->getInt(C1->getValue() & ~RHS->getValue()));
|
|
}
|
|
|
|
// Try to fold constant and into select arguments.
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
|
|
if (Instruction *R = FoldOpIntoSelect(I, SI))
|
|
return R;
|
|
|
|
if (isa<PHINode>(Op0))
|
|
if (Instruction *NV = FoldOpIntoPhi(I))
|
|
return NV;
|
|
}
|
|
|
|
// Given an OR instruction, check to see if this is a bswap.
|
|
if (Instruction *BSwap = MatchBSwap(I))
|
|
return BSwap;
|
|
|
|
Value *A = nullptr, *B = nullptr;
|
|
ConstantInt *C1 = nullptr, *C2 = nullptr;
|
|
|
|
// (X^C)|Y -> (X|Y)^C iff Y&C == 0
|
|
if (Op0->hasOneUse() &&
|
|
match(Op0, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
|
|
MaskedValueIsZero(Op1, C1->getValue(), 0, &I)) {
|
|
Value *NOr = Builder->CreateOr(A, Op1);
|
|
NOr->takeName(Op0);
|
|
return BinaryOperator::CreateXor(NOr, C1);
|
|
}
|
|
|
|
// Y|(X^C) -> (X|Y)^C iff Y&C == 0
|
|
if (Op1->hasOneUse() &&
|
|
match(Op1, m_Xor(m_Value(A), m_ConstantInt(C1))) &&
|
|
MaskedValueIsZero(Op0, C1->getValue(), 0, &I)) {
|
|
Value *NOr = Builder->CreateOr(A, Op0);
|
|
NOr->takeName(Op0);
|
|
return BinaryOperator::CreateXor(NOr, C1);
|
|
}
|
|
|
|
// ((~A & B) | A) -> (A | B)
|
|
if (match(Op0, m_And(m_Not(m_Value(A)), m_Value(B))) &&
|
|
match(Op1, m_Specific(A)))
|
|
return BinaryOperator::CreateOr(A, B);
|
|
|
|
// ((A & B) | ~A) -> (~A | B)
|
|
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
|
|
match(Op1, m_Not(m_Specific(A))))
|
|
return BinaryOperator::CreateOr(Builder->CreateNot(A), B);
|
|
|
|
// (A & (~B)) | (A ^ B) -> (A ^ B)
|
|
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
|
|
match(Op1, m_Xor(m_Specific(A), m_Specific(B))))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
|
|
// (A ^ B) | ( A & (~B)) -> (A ^ B)
|
|
if (match(Op0, m_Xor(m_Value(A), m_Value(B))) &&
|
|
match(Op1, m_And(m_Specific(A), m_Not(m_Specific(B)))))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
|
|
// (A & C)|(B & D)
|
|
Value *C = nullptr, *D = nullptr;
|
|
if (match(Op0, m_And(m_Value(A), m_Value(C))) &&
|
|
match(Op1, m_And(m_Value(B), m_Value(D)))) {
|
|
Value *V1 = nullptr, *V2 = nullptr;
|
|
C1 = dyn_cast<ConstantInt>(C);
|
|
C2 = dyn_cast<ConstantInt>(D);
|
|
if (C1 && C2) { // (A & C1)|(B & C2)
|
|
if ((C1->getValue() & C2->getValue()) == 0) {
|
|
// ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2)
|
|
// iff (C1&C2) == 0 and (N&~C1) == 0
|
|
if (match(A, m_Or(m_Value(V1), m_Value(V2))) &&
|
|
((V1 == B &&
|
|
MaskedValueIsZero(V2, ~C1->getValue(), 0, &I)) || // (V|N)
|
|
(V2 == B &&
|
|
MaskedValueIsZero(V1, ~C1->getValue(), 0, &I)))) // (N|V)
|
|
return BinaryOperator::CreateAnd(A,
|
|
Builder->getInt(C1->getValue()|C2->getValue()));
|
|
// Or commutes, try both ways.
|
|
if (match(B, m_Or(m_Value(V1), m_Value(V2))) &&
|
|
((V1 == A &&
|
|
MaskedValueIsZero(V2, ~C2->getValue(), 0, &I)) || // (V|N)
|
|
(V2 == A &&
|
|
MaskedValueIsZero(V1, ~C2->getValue(), 0, &I)))) // (N|V)
|
|
return BinaryOperator::CreateAnd(B,
|
|
Builder->getInt(C1->getValue()|C2->getValue()));
|
|
|
|
// ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
|
|
// iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
|
|
ConstantInt *C3 = nullptr, *C4 = nullptr;
|
|
if (match(A, m_Or(m_Value(V1), m_ConstantInt(C3))) &&
|
|
(C3->getValue() & ~C1->getValue()) == 0 &&
|
|
match(B, m_Or(m_Specific(V1), m_ConstantInt(C4))) &&
|
|
(C4->getValue() & ~C2->getValue()) == 0) {
|
|
V2 = Builder->CreateOr(V1, ConstantExpr::getOr(C3, C4), "bitfield");
|
|
return BinaryOperator::CreateAnd(V2,
|
|
Builder->getInt(C1->getValue()|C2->getValue()));
|
|
}
|
|
}
|
|
}
|
|
|
|
// 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, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(A, C, D, B, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(C, A, B, D, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(C, A, D, B, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(B, D, A, C, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(B, D, C, A, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(D, B, A, C, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
if (Value *V = matchSelectFromAndOr(D, B, C, A, *Builder))
|
|
return replaceInstUsesWith(I, V);
|
|
}
|
|
|
|
// ((A&~B)|(~A&B)) -> A^B
|
|
if ((match(C, m_Not(m_Specific(D))) &&
|
|
match(B, m_Not(m_Specific(A)))))
|
|
return BinaryOperator::CreateXor(A, D);
|
|
// ((~B&A)|(~A&B)) -> A^B
|
|
if ((match(A, m_Not(m_Specific(D))) &&
|
|
match(B, m_Not(m_Specific(C)))))
|
|
return BinaryOperator::CreateXor(C, D);
|
|
// ((A&~B)|(B&~A)) -> A^B
|
|
if ((match(C, m_Not(m_Specific(B))) &&
|
|
match(D, m_Not(m_Specific(A)))))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
// ((~B&A)|(B&~A)) -> A^B
|
|
if ((match(A, m_Not(m_Specific(B))) &&
|
|
match(D, m_Not(m_Specific(C)))))
|
|
return BinaryOperator::CreateXor(C, B);
|
|
|
|
// ((A|B)&1)|(B&-2) -> (A&1) | B
|
|
if (match(A, m_Or(m_Value(V1), m_Specific(B))) ||
|
|
match(A, m_Or(m_Specific(B), m_Value(V1)))) {
|
|
Instruction *Ret = FoldOrWithConstants(I, Op1, V1, B, C);
|
|
if (Ret) return Ret;
|
|
}
|
|
// (B&-2)|((A|B)&1) -> (A&1) | B
|
|
if (match(B, m_Or(m_Specific(A), m_Value(V1))) ||
|
|
match(B, m_Or(m_Value(V1), m_Specific(A)))) {
|
|
Instruction *Ret = FoldOrWithConstants(I, Op0, A, V1, D);
|
|
if (Ret) return Ret;
|
|
}
|
|
// ((A^B)&1)|(B&-2) -> (A&1) ^ B
|
|
if (match(A, m_Xor(m_Value(V1), m_Specific(B))) ||
|
|
match(A, m_Xor(m_Specific(B), m_Value(V1)))) {
|
|
Instruction *Ret = FoldXorWithConstants(I, Op1, V1, B, C);
|
|
if (Ret) return Ret;
|
|
}
|
|
// (B&-2)|((A^B)&1) -> (A&1) ^ B
|
|
if (match(B, m_Xor(m_Specific(A), m_Value(V1))) ||
|
|
match(B, m_Xor(m_Value(V1), m_Specific(A)))) {
|
|
Instruction *Ret = FoldXorWithConstants(I, Op0, A, V1, D);
|
|
if (Ret) return Ret;
|
|
}
|
|
}
|
|
|
|
// (A ^ B) | ((B ^ C) ^ A) -> (A ^ B) | C
|
|
if (match(Op0, m_Xor(m_Value(A), m_Value(B))))
|
|
if (match(Op1, m_Xor(m_Xor(m_Specific(B), m_Value(C)), m_Specific(A))))
|
|
if (Op1->hasOneUse() || cast<BinaryOperator>(Op1)->hasOneUse())
|
|
return BinaryOperator::CreateOr(Op0, C);
|
|
|
|
// ((A ^ C) ^ B) | (B ^ A) -> (B ^ A) | C
|
|
if (match(Op0, m_Xor(m_Xor(m_Value(A), m_Value(C)), m_Value(B))))
|
|
if (match(Op1, m_Xor(m_Specific(B), m_Specific(A))))
|
|
if (Op0->hasOneUse() || cast<BinaryOperator>(Op0)->hasOneUse())
|
|
return BinaryOperator::CreateOr(Op1, C);
|
|
|
|
// ((B | C) & A) | B -> B | (A & C)
|
|
if (match(Op0, m_And(m_Or(m_Specific(Op1), m_Value(C)), m_Value(A))))
|
|
return BinaryOperator::CreateOr(Op1, Builder->CreateAnd(A, C));
|
|
|
|
if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
|
|
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;
|
|
}
|
|
|
|
// A | ( A ^ B) -> A | B
|
|
// A | (~A ^ B) -> A | ~B
|
|
// (A & B) | (A ^ B)
|
|
if (match(Op1, m_Xor(m_Value(A), m_Value(B)))) {
|
|
if (Op0 == A || Op0 == B)
|
|
return BinaryOperator::CreateOr(A, B);
|
|
|
|
if (match(Op0, m_And(m_Specific(A), m_Specific(B))) ||
|
|
match(Op0, m_And(m_Specific(B), m_Specific(A))))
|
|
return BinaryOperator::CreateOr(A, B);
|
|
|
|
if (Op1->hasOneUse() && match(A, m_Not(m_Specific(Op0)))) {
|
|
Value *Not = Builder->CreateNot(B, B->getName()+".not");
|
|
return BinaryOperator::CreateOr(Not, Op0);
|
|
}
|
|
if (Op1->hasOneUse() && match(B, m_Not(m_Specific(Op0)))) {
|
|
Value *Not = Builder->CreateNot(A, A->getName()+".not");
|
|
return BinaryOperator::CreateOr(Not, Op0);
|
|
}
|
|
}
|
|
|
|
// A | ~(A | B) -> A | ~B
|
|
// A | ~(A ^ B) -> A | ~B
|
|
if (match(Op1, m_Not(m_Value(A))))
|
|
if (BinaryOperator *B = dyn_cast<BinaryOperator>(A))
|
|
if ((Op0 == B->getOperand(0) || Op0 == B->getOperand(1)) &&
|
|
Op1->hasOneUse() && (B->getOpcode() == Instruction::Or ||
|
|
B->getOpcode() == Instruction::Xor)) {
|
|
Value *NotOp = Op0 == B->getOperand(0) ? B->getOperand(1) :
|
|
B->getOperand(0);
|
|
Value *Not = Builder->CreateNot(NotOp, NotOp->getName()+".not");
|
|
return BinaryOperator::CreateOr(Not, Op0);
|
|
}
|
|
|
|
// (A & B) | ((~A) ^ B) -> (~A ^ B)
|
|
if (match(Op0, m_And(m_Value(A), m_Value(B))) &&
|
|
match(Op1, m_Xor(m_Not(m_Specific(A)), m_Specific(B))))
|
|
return BinaryOperator::CreateXor(Builder->CreateNot(A), B);
|
|
|
|
// ((~A) ^ B) | (A & B) -> (~A ^ B)
|
|
if (match(Op0, m_Xor(m_Not(m_Value(A)), m_Value(B))) &&
|
|
match(Op1, m_And(m_Specific(A), m_Specific(B))))
|
|
return BinaryOperator::CreateXor(Builder->CreateNot(A), B);
|
|
|
|
if (SwappedForXor)
|
|
std::swap(Op0, Op1);
|
|
|
|
{
|
|
ICmpInst *LHS = dyn_cast<ICmpInst>(Op0);
|
|
ICmpInst *RHS = dyn_cast<ICmpInst>(Op1);
|
|
if (LHS && RHS)
|
|
if (Value *Res = FoldOrOfICmps(LHS, RHS, &I))
|
|
return replaceInstUsesWith(I, Res);
|
|
|
|
// TODO: Make this recursive; it's a little tricky because an arbitrary
|
|
// number of 'or' instructions might have to be created.
|
|
Value *X, *Y;
|
|
if (LHS && match(Op1, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(X))
|
|
if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
|
|
return replaceInstUsesWith(I, Builder->CreateOr(Res, Y));
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
|
|
if (Value *Res = FoldOrOfICmps(LHS, Cmp, &I))
|
|
return replaceInstUsesWith(I, Builder->CreateOr(Res, X));
|
|
}
|
|
if (RHS && match(Op0, m_OneUse(m_Or(m_Value(X), m_Value(Y))))) {
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(X))
|
|
if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
|
|
return replaceInstUsesWith(I, Builder->CreateOr(Res, Y));
|
|
if (auto *Cmp = dyn_cast<ICmpInst>(Y))
|
|
if (Value *Res = FoldOrOfICmps(Cmp, RHS, &I))
|
|
return replaceInstUsesWith(I, Builder->CreateOr(Res, X));
|
|
}
|
|
}
|
|
|
|
// (fcmp uno x, c) | (fcmp uno y, c) -> (fcmp uno x, y)
|
|
if (FCmpInst *LHS = dyn_cast<FCmpInst>(I.getOperand(0)))
|
|
if (FCmpInst *RHS = dyn_cast<FCmpInst>(I.getOperand(1)))
|
|
if (Value *Res = FoldOrOfFCmps(LHS, RHS))
|
|
return replaceInstUsesWith(I, Res);
|
|
|
|
if (Instruction *CastedOr = foldCastedBitwiseLogic(I))
|
|
return CastedOr;
|
|
|
|
// or(sext(A), B) / or(B, sext(A)) --> A ? -1 : B, where A is i1 or <N x i1>.
|
|
if (match(Op0, m_OneUse(m_SExt(m_Value(A)))) &&
|
|
A->getType()->getScalarType()->isIntegerTy(1))
|
|
return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op1);
|
|
if (match(Op1, m_OneUse(m_SExt(m_Value(A)))) &&
|
|
A->getType()->getScalarType()->isIntegerTy(1))
|
|
return SelectInst::Create(A, ConstantInt::getSigned(I.getType(), -1), Op0);
|
|
|
|
// 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
|
|
if (Op0->hasOneUse() && !isa<ConstantInt>(Op1) &&
|
|
match(Op0, m_Or(m_Value(A), m_ConstantInt(C1)))) {
|
|
Value *Inner = Builder->CreateOr(A, Op1);
|
|
Inner->takeName(Op0);
|
|
return BinaryOperator::CreateOr(Inner, C1);
|
|
}
|
|
|
|
// 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);
|
|
}
|
|
}
|
|
|
|
return Changed ? &I : nullptr;
|
|
}
|
|
|
|
Instruction *InstCombiner::visitXor(BinaryOperator &I) {
|
|
bool Changed = SimplifyAssociativeOrCommutative(I);
|
|
Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
|
|
|
|
if (Value *V = SimplifyVectorOp(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
if (Value *V = SimplifyXorInst(Op0, Op1, DL, &TLI, &DT, &AC))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
// (A&B)^(A&C) -> A&(B^C) etc
|
|
if (Value *V = SimplifyUsingDistributiveLaws(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 (Value *V = SimplifyBSwap(I))
|
|
return replaceInstUsesWith(I, V);
|
|
|
|
// Is this a ~ operation?
|
|
if (Value *NotOp = dyn_castNotVal(&I)) {
|
|
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(NotOp)) {
|
|
if (Op0I->getOpcode() == Instruction::And ||
|
|
Op0I->getOpcode() == Instruction::Or) {
|
|
// ~(~X & Y) --> (X | ~Y) - De Morgan's Law
|
|
// ~(~X | Y) === (X & ~Y) - De Morgan's Law
|
|
if (dyn_castNotVal(Op0I->getOperand(1)))
|
|
Op0I->swapOperands();
|
|
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0))) {
|
|
Value *NotY =
|
|
Builder->CreateNot(Op0I->getOperand(1),
|
|
Op0I->getOperand(1)->getName()+".not");
|
|
if (Op0I->getOpcode() == Instruction::And)
|
|
return BinaryOperator::CreateOr(Op0NotVal, NotY);
|
|
return BinaryOperator::CreateAnd(Op0NotVal, NotY);
|
|
}
|
|
|
|
// ~(X & Y) --> (~X | ~Y) - De Morgan's Law
|
|
// ~(X | Y) === (~X & ~Y) - De Morgan's Law
|
|
if (IsFreeToInvert(Op0I->getOperand(0),
|
|
Op0I->getOperand(0)->hasOneUse()) &&
|
|
IsFreeToInvert(Op0I->getOperand(1),
|
|
Op0I->getOperand(1)->hasOneUse())) {
|
|
Value *NotX =
|
|
Builder->CreateNot(Op0I->getOperand(0), "notlhs");
|
|
Value *NotY =
|
|
Builder->CreateNot(Op0I->getOperand(1), "notrhs");
|
|
if (Op0I->getOpcode() == Instruction::And)
|
|
return BinaryOperator::CreateOr(NotX, NotY);
|
|
return BinaryOperator::CreateAnd(NotX, NotY);
|
|
}
|
|
|
|
} else if (Op0I->getOpcode() == Instruction::AShr) {
|
|
// ~(~X >>s Y) --> (X >>s Y)
|
|
if (Value *Op0NotVal = dyn_castNotVal(Op0I->getOperand(0)))
|
|
return BinaryOperator::CreateAShr(Op0NotVal, Op0I->getOperand(1));
|
|
}
|
|
}
|
|
}
|
|
|
|
if (Constant *RHS = dyn_cast<Constant>(Op1)) {
|
|
if (RHS->isAllOnesValue() && Op0->hasOneUse())
|
|
// xor (cmp A, B), true = not (cmp A, B) = !cmp A, B
|
|
if (CmpInst *CI = dyn_cast<CmpInst>(Op0))
|
|
return CmpInst::Create(CI->getOpcode(),
|
|
CI->getInversePredicate(),
|
|
CI->getOperand(0), CI->getOperand(1));
|
|
}
|
|
|
|
if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
|
|
// fold (xor(zext(cmp)), 1) and (xor(sext(cmp)), -1) to ext(!cmp).
|
|
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
|
|
if (CmpInst *CI = dyn_cast<CmpInst>(Op0C->getOperand(0))) {
|
|
if (CI->hasOneUse() && Op0C->hasOneUse()) {
|
|
Instruction::CastOps Opcode = Op0C->getOpcode();
|
|
if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
|
|
(RHS == ConstantExpr::getCast(Opcode, Builder->getTrue(),
|
|
Op0C->getDestTy()))) {
|
|
CI->setPredicate(CI->getInversePredicate());
|
|
return CastInst::Create(Opcode, CI, Op0C->getType());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0)) {
|
|
// ~(c-X) == X-c-1 == X+(-c-1)
|
|
if (Op0I->getOpcode() == Instruction::Sub && RHS->isAllOnesValue())
|
|
if (Constant *Op0I0C = dyn_cast<Constant>(Op0I->getOperand(0))) {
|
|
Constant *NegOp0I0C = ConstantExpr::getNeg(Op0I0C);
|
|
Constant *ConstantRHS = ConstantExpr::getSub(NegOp0I0C,
|
|
ConstantInt::get(I.getType(), 1));
|
|
return BinaryOperator::CreateAdd(Op0I->getOperand(1), ConstantRHS);
|
|
}
|
|
|
|
if (ConstantInt *Op0CI = dyn_cast<ConstantInt>(Op0I->getOperand(1))) {
|
|
if (Op0I->getOpcode() == Instruction::Add) {
|
|
// ~(X-c) --> (-c-1)-X
|
|
if (RHS->isAllOnesValue()) {
|
|
Constant *NegOp0CI = ConstantExpr::getNeg(Op0CI);
|
|
return BinaryOperator::CreateSub(
|
|
ConstantExpr::getSub(NegOp0CI,
|
|
ConstantInt::get(I.getType(), 1)),
|
|
Op0I->getOperand(0));
|
|
} else if (RHS->getValue().isSignBit()) {
|
|
// (X + C) ^ signbit -> (X + C + signbit)
|
|
Constant *C = Builder->getInt(RHS->getValue() + Op0CI->getValue());
|
|
return BinaryOperator::CreateAdd(Op0I->getOperand(0), C);
|
|
|
|
}
|
|
} else if (Op0I->getOpcode() == Instruction::Or) {
|
|
// (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0
|
|
if (MaskedValueIsZero(Op0I->getOperand(0), Op0CI->getValue(),
|
|
0, &I)) {
|
|
Constant *NewRHS = ConstantExpr::getOr(Op0CI, RHS);
|
|
// Anything in both C1 and C2 is known to be zero, remove it from
|
|
// NewRHS.
|
|
Constant *CommonBits = ConstantExpr::getAnd(Op0CI, RHS);
|
|
NewRHS = ConstantExpr::getAnd(NewRHS,
|
|
ConstantExpr::getNot(CommonBits));
|
|
Worklist.Add(Op0I);
|
|
I.setOperand(0, Op0I->getOperand(0));
|
|
I.setOperand(1, NewRHS);
|
|
return &I;
|
|
}
|
|
} else if (Op0I->getOpcode() == Instruction::LShr) {
|
|
// ((X^C1) >> C2) ^ C3 -> (X>>C2) ^ ((C1>>C2)^C3)
|
|
// E1 = "X ^ C1"
|
|
BinaryOperator *E1;
|
|
ConstantInt *C1;
|
|
if (Op0I->hasOneUse() &&
|
|
(E1 = dyn_cast<BinaryOperator>(Op0I->getOperand(0))) &&
|
|
E1->getOpcode() == Instruction::Xor &&
|
|
(C1 = dyn_cast<ConstantInt>(E1->getOperand(1)))) {
|
|
// fold (C1 >> C2) ^ C3
|
|
ConstantInt *C2 = Op0CI, *C3 = RHS;
|
|
APInt FoldConst = C1->getValue().lshr(C2->getValue());
|
|
FoldConst ^= C3->getValue();
|
|
// Prepare the two operands.
|
|
Value *Opnd0 = Builder->CreateLShr(E1->getOperand(0), C2);
|
|
Opnd0->takeName(Op0I);
|
|
cast<Instruction>(Opnd0)->setDebugLoc(I.getDebugLoc());
|
|
Value *FoldVal = ConstantInt::get(Opnd0->getType(), FoldConst);
|
|
|
|
return BinaryOperator::CreateXor(Opnd0, FoldVal);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Try to fold constant and into select arguments.
|
|
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
|
|
if (Instruction *R = FoldOpIntoSelect(I, SI))
|
|
return R;
|
|
if (isa<PHINode>(Op0))
|
|
if (Instruction *NV = FoldOpIntoPhi(I))
|
|
return NV;
|
|
}
|
|
|
|
BinaryOperator *Op1I = dyn_cast<BinaryOperator>(Op1);
|
|
if (Op1I) {
|
|
Value *A, *B;
|
|
if (match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
|
|
if (A == Op0) { // B^(B|A) == (A|B)^B
|
|
Op1I->swapOperands();
|
|
I.swapOperands();
|
|
std::swap(Op0, Op1);
|
|
} else if (B == Op0) { // B^(A|B) == (A|B)^B
|
|
I.swapOperands(); // Simplified below.
|
|
std::swap(Op0, Op1);
|
|
}
|
|
} else if (match(Op1I, m_And(m_Value(A), m_Value(B))) &&
|
|
Op1I->hasOneUse()){
|
|
if (A == Op0) { // A^(A&B) -> A^(B&A)
|
|
Op1I->swapOperands();
|
|
std::swap(A, B);
|
|
}
|
|
if (B == Op0) { // A^(B&A) -> (B&A)^A
|
|
I.swapOperands(); // Simplified below.
|
|
std::swap(Op0, Op1);
|
|
}
|
|
}
|
|
}
|
|
|
|
BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0);
|
|
if (Op0I) {
|
|
Value *A, *B;
|
|
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
|
|
Op0I->hasOneUse()) {
|
|
if (A == Op1) // (B|A)^B == (A|B)^B
|
|
std::swap(A, B);
|
|
if (B == Op1) // (A|B)^B == A & ~B
|
|
return BinaryOperator::CreateAnd(A, Builder->CreateNot(Op1));
|
|
} else if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
|
|
Op0I->hasOneUse()){
|
|
if (A == Op1) // (A&B)^A -> (B&A)^A
|
|
std::swap(A, B);
|
|
if (B == Op1 && // (B&A)^A == ~B & A
|
|
!isa<ConstantInt>(Op1)) { // Canonical form is (B&C)^C
|
|
return BinaryOperator::CreateAnd(Builder->CreateNot(A), Op1);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (Op0I && Op1I) {
|
|
Value *A, *B, *C, *D;
|
|
// (A & B)^(A | B) -> A ^ B
|
|
if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
|
|
match(Op1I, m_Or(m_Value(C), m_Value(D)))) {
|
|
if ((A == C && B == D) || (A == D && B == C))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (A | B)^(A & B) -> A ^ B
|
|
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
|
|
match(Op1I, m_And(m_Value(C), m_Value(D)))) {
|
|
if ((A == C && B == D) || (A == D && B == C))
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (A | ~B) ^ (~A | B) -> A ^ B
|
|
if (match(Op0I, m_Or(m_Value(A), m_Not(m_Value(B)))) &&
|
|
match(Op1I, m_Or(m_Not(m_Specific(A)), m_Specific(B)))) {
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (~A | B) ^ (A | ~B) -> A ^ B
|
|
if (match(Op0I, m_Or(m_Not(m_Value(A)), m_Value(B))) &&
|
|
match(Op1I, m_Or(m_Specific(A), m_Not(m_Specific(B))))) {
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (A & ~B) ^ (~A & B) -> A ^ B
|
|
if (match(Op0I, m_And(m_Value(A), m_Not(m_Value(B)))) &&
|
|
match(Op1I, m_And(m_Not(m_Specific(A)), m_Specific(B)))) {
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (~A & B) ^ (A & ~B) -> A ^ B
|
|
if (match(Op0I, m_And(m_Not(m_Value(A)), m_Value(B))) &&
|
|
match(Op1I, m_And(m_Specific(A), m_Not(m_Specific(B))))) {
|
|
return BinaryOperator::CreateXor(A, B);
|
|
}
|
|
// (A ^ C)^(A | B) -> ((~A) & B) ^ C
|
|
if (match(Op0I, m_Xor(m_Value(D), m_Value(C))) &&
|
|
match(Op1I, m_Or(m_Value(A), m_Value(B)))) {
|
|
if (D == A)
|
|
return BinaryOperator::CreateXor(
|
|
Builder->CreateAnd(Builder->CreateNot(A), B), C);
|
|
if (D == B)
|
|
return BinaryOperator::CreateXor(
|
|
Builder->CreateAnd(Builder->CreateNot(B), A), C);
|
|
}
|
|
// (A | B)^(A ^ C) -> ((~A) & B) ^ C
|
|
if (match(Op0I, m_Or(m_Value(A), m_Value(B))) &&
|
|
match(Op1I, m_Xor(m_Value(D), m_Value(C)))) {
|
|
if (D == A)
|
|
return BinaryOperator::CreateXor(
|
|
Builder->CreateAnd(Builder->CreateNot(A), B), C);
|
|
if (D == B)
|
|
return BinaryOperator::CreateXor(
|
|
Builder->CreateAnd(Builder->CreateNot(B), A), C);
|
|
}
|
|
// (A & B) ^ (A ^ B) -> (A | B)
|
|
if (match(Op0I, m_And(m_Value(A), m_Value(B))) &&
|
|
match(Op1I, m_Xor(m_Specific(A), m_Specific(B))))
|
|
return BinaryOperator::CreateOr(A, B);
|
|
// (A ^ B) ^ (A & B) -> (A | B)
|
|
if (match(Op0I, m_Xor(m_Value(A), m_Value(B))) &&
|
|
match(Op1I, m_And(m_Specific(A), m_Specific(B))))
|
|
return BinaryOperator::CreateOr(A, B);
|
|
}
|
|
|
|
Value *A = nullptr, *B = nullptr;
|
|
// (A & ~B) ^ (~A) -> ~(A & B)
|
|
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
|
|
match(Op1, m_Not(m_Specific(A))))
|
|
return BinaryOperator::CreateNot(Builder->CreateAnd(A, B));
|
|
|
|
// (icmp1 A, B) ^ (icmp2 A, B) --> (icmp3 A, B)
|
|
if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1)))
|
|
if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0)))
|
|
if (PredicatesFoldable(LHS->getPredicate(), RHS->getPredicate())) {
|
|
if (LHS->getOperand(0) == RHS->getOperand(1) &&
|
|
LHS->getOperand(1) == RHS->getOperand(0))
|
|
LHS->swapOperands();
|
|
if (LHS->getOperand(0) == RHS->getOperand(0) &&
|
|
LHS->getOperand(1) == RHS->getOperand(1)) {
|
|
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
|
|
unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS);
|
|
bool isSigned = LHS->isSigned() || RHS->isSigned();
|
|
return replaceInstUsesWith(I,
|
|
getNewICmpValue(isSigned, Code, Op0, Op1,
|
|
Builder));
|
|
}
|
|
}
|
|
|
|
if (Instruction *CastedXor = foldCastedBitwiseLogic(I))
|
|
return CastedXor;
|
|
|
|
return Changed ? &I : nullptr;
|
|
}
|