diff options
Diffstat (limited to 'lib/Transforms/InstCombine/InstCombineAndOrXor.cpp')
| -rw-r--r-- | lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 410 |
1 files changed, 240 insertions, 170 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 7d0af0d..990cbc3 100644 --- a/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -12,18 +12,18 @@ //===----------------------------------------------------------------------===// #include "InstCombine.h" -#include "llvm/Intrinsics.h" #include "llvm/Analysis/InstructionSimplify.h" -#include "llvm/Transforms/Utils/CmpInstAnalysis.h" +#include "llvm/IR/Intrinsics.h" #include "llvm/Support/ConstantRange.h" #include "llvm/Support/PatternMatch.h" +#include "llvm/Transforms/Utils/CmpInstAnalysis.h" using namespace llvm; using namespace PatternMatch; /// AddOne - Add one to a ConstantInt. -static Constant *AddOne(Constant *C) { - return ConstantExpr::getAdd(C, ConstantInt::get(C->getType(), 1)); +static Constant *AddOne(ConstantInt *C) { + return ConstantInt::get(C->getContext(), C->getValue() + 1); } /// SubOne - Subtract one from a ConstantInt. static Constant *SubOne(ConstantInt *C) { @@ -36,15 +36,15 @@ static inline bool isFreeToInvert(Value *V) { // ~(~(X)) -> X. if (BinaryOperator::isNot(V)) return true; - + // Constants can be considered to be not'ed values. if (isa<ConstantInt>(V)) return true; - + // Compares can be inverted if they have a single use. if (CmpInst *CI = dyn_cast<CmpInst>(V)) return CI->hasOneUse(); - + return false; } @@ -56,7 +56,7 @@ static inline Value *dyn_castNotVal(Value *V) { if (!isFreeToInvert(Operand)) return Operand; } - + // Constants can be considered to be not'ed values... if (ConstantInt *C = dyn_cast<ConstantInt>(V)) return ConstantInt::get(C->getType(), ~C->getValue()); @@ -91,7 +91,7 @@ static unsigned getFCmpCode(FCmpInst::Predicate CC, bool &isOrdered) { } /// getNewICmpValue - This is the complement of getICmpCode, which turns an -/// opcode and two operands into either a constant true or false, or a brand +/// opcode and two operands into either a constant true or false, or a brand /// new ICmp instruction. The sign is passed in to determine which kind /// of predicate to use in the new icmp instruction. static Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS, @@ -118,7 +118,7 @@ static Value *getFCmpValue(bool isordered, unsigned code, case 4: Pred = isordered ? FCmpInst::FCMP_OLT : FCmpInst::FCMP_ULT; break; case 5: Pred = isordered ? FCmpInst::FCMP_ONE : FCmpInst::FCMP_UNE; break; case 6: Pred = isordered ? FCmpInst::FCMP_OLE : FCmpInst::FCMP_ULE; break; - case 7: + case 7: if (!isordered) return ConstantInt::getTrue(LHS->getContext()); Pred = FCmpInst::FCMP_ORD; break; } @@ -154,7 +154,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, Or->takeName(Op); return BinaryOperator::CreateAnd(Or, AndRHS); } - + ConstantInt *TogetherCI = dyn_cast<ConstantInt>(Together); if (TogetherCI && !TogetherCI->isZero()){ // (X | C1) & C2 --> (X & (C2^(C1&C2))) | C1 @@ -166,7 +166,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, return BinaryOperator::CreateOr(And, OpRHS); } } - + break; case Instruction::Add: if (Op->hasOneUse()) { @@ -215,7 +215,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, if (CI->getValue() == ShlMask) // Masking out bits that the shift already masks. return ReplaceInstUsesWith(TheAnd, Op); // No need for the and. - + if (CI != AndRHS) { // Reducing bits set in and. TheAnd.setOperand(1, CI); return &TheAnd; @@ -236,7 +236,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, if (CI->getValue() == ShrMask) // Masking out bits that the shift already masks. return ReplaceInstUsesWith(TheAnd, Op); - + if (CI != AndRHS) { TheAnd.setOperand(1, CI); // Reduce bits set in and cst. return &TheAnd; @@ -269,22 +269,22 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op, /// InsertRangeTest - Emit a computation of: (V >= Lo && V < Hi) if Inside is /// true, otherwise (V < Lo || V >= Hi). In practice, we emit the more efficient -/// (V-Lo) <u Hi-Lo. This method expects that Lo <= Hi. isSigned indicates +/// (V-Lo) \<u Hi-Lo. This method expects that Lo <= Hi. isSigned indicates /// whether to treat the V, Lo and HI as signed or not. IB is the location to /// insert new instructions. Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, bool isSigned, bool Inside) { - assert(cast<ConstantInt>(ConstantExpr::getICmp((isSigned ? + assert(cast<ConstantInt>(ConstantExpr::getICmp((isSigned ? ICmpInst::ICMP_SLE:ICmpInst::ICMP_ULE), Lo, Hi))->getZExtValue() && "Lo is not <= Hi in range emission code!"); - + if (Inside) { if (Lo == Hi) // Trivially false. return ConstantInt::getFalse(V->getContext()); // V >= Min && V < Hi --> V < Hi if (cast<ConstantInt>(Lo)->isMinValue(isSigned)) { - ICmpInst::Predicate pred = (isSigned ? + ICmpInst::Predicate pred = (isSigned ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT); return Builder->CreateICmp(pred, V, Hi); } @@ -302,7 +302,7 @@ Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, // V < Min || V >= Hi -> V > Hi-1 Hi = SubOne(cast<ConstantInt>(Hi)); if (cast<ConstantInt>(Lo)->isMinValue(isSigned)) { - ICmpInst::Predicate pred = (isSigned ? + ICmpInst::Predicate pred = (isSigned ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT); return Builder->CreateICmp(pred, V, Hi); } @@ -327,14 +327,14 @@ static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) { // look for the first zero bit after the run of ones MB = BitWidth - ((V - 1) ^ V).countLeadingZeros(); // look for the first non-zero bit - ME = V.getActiveBits(); + ME = V.getActiveBits(); return true; } /// FoldLogicalPlusAnd - This is part of an expression (LHS +/- RHS) & Mask, /// where isSub determines whether the operator is a sub. If we can fold one of /// the following xforms: -/// +/// /// ((A & N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == Mask /// ((A | N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0 /// ((A ^ N) +/- B) & Mask -> (A +/- B) & Mask iff N&Mask == 0 @@ -355,8 +355,8 @@ Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS, case Instruction::And: if (ConstantExpr::getAnd(N, Mask) == Mask) { // If the AndRHS is a power of two minus one (0+1+), this is simple. - if ((Mask->getValue().countLeadingZeros() + - Mask->getValue().countPopulation()) == + if ((Mask->getValue().countLeadingZeros() + + Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth()) break; @@ -375,33 +375,33 @@ Value *InstCombiner::FoldLogicalPlusAnd(Value *LHS, Value *RHS, case Instruction::Or: case Instruction::Xor: // If the AndRHS is a power of two minus one (0+1+), and N&Mask == 0 - if ((Mask->getValue().countLeadingZeros() + + if ((Mask->getValue().countLeadingZeros() + Mask->getValue().countPopulation()) == Mask->getValue().getBitWidth() && ConstantExpr::getAnd(N, Mask)->isNullValue()) break; return 0; } - + if (isSub) return Builder->CreateSub(LHSI->getOperand(0), RHS, "fold"); return Builder->CreateAdd(LHSI->getOperand(0), RHS, "fold"); } /// enum for classifying (icmp eq (A & B), C) and (icmp ne (A & B), C) -/// One of A and B is considered the mask, the other the value. This is -/// described as the "AMask" or "BMask" part of the enum. If the enum +/// One of A and B is considered the mask, the other the value. This is +/// described as the "AMask" or "BMask" part of the enum. If the enum /// contains only "Mask", then both A and B can be considered masks. /// If A is the mask, then it was proven, that (A & C) == C. This /// is trivial if C == A, or C == 0. If both A and C are constants, this /// proof is also easy. /// For the following explanations we assume that A is the mask. -/// The part "AllOnes" declares, that the comparison is true only +/// The part "AllOnes" declares, that the comparison is true only /// if (A & B) == A, or all bits of A are set in B. /// Example: (icmp eq (A & 3), 3) -> FoldMskICmp_AMask_AllOnes -/// The part "AllZeroes" declares, that the comparison is true only +/// The part "AllZeroes" declares, that the comparison is true only /// if (A & B) == 0, or all bits of A are cleared in B. /// Example: (icmp eq (A & 3), 0) -> FoldMskICmp_Mask_AllZeroes -/// The part "Mixed" declares, that (A & B) == C and C might or might not +/// The part "Mixed" declares, that (A & B) == C and C might or might not /// contain any number of one bits and zero bits. /// Example: (icmp eq (A & 3), 1) -> FoldMskICmp_AMask_Mixed /// The Part "Not" means, that in above descriptions "==" should be replaced @@ -425,16 +425,16 @@ enum MaskedICmpType { /// return the set of pattern classes (from MaskedICmpType) /// that (icmp SCC (A & B), C) satisfies -static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C, +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 != 0 && !ACst->isZero() && + bool icmp_abit = (ACst != 0 && !ACst->isZero() && ACst->getValue().isPowerOf2()); - bool icmp_bbit = (BCst != 0 && !BCst->isZero() && + bool icmp_bbit = (BCst != 0 && !BCst->isZero() && BCst->getValue().isPowerOf2()); unsigned result = 0; if (CCst != 0 && CCst->isZero()) { @@ -449,12 +449,12 @@ static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C, FoldMskICmp_BMask_NotMixed)); if (icmp_abit) result |= (icmp_eq ? (FoldMskICmp_AMask_NotAllOnes | - FoldMskICmp_AMask_NotMixed) + FoldMskICmp_AMask_NotMixed) : (FoldMskICmp_AMask_AllOnes | FoldMskICmp_AMask_Mixed)); if (icmp_bbit) result |= (icmp_eq ? (FoldMskICmp_BMask_NotAllOnes | - FoldMskICmp_BMask_NotMixed) + FoldMskICmp_BMask_NotMixed) : (FoldMskICmp_BMask_AllOnes | FoldMskICmp_BMask_Mixed)); return result; @@ -469,26 +469,23 @@ static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C, FoldMskICmp_AMask_NotMixed) : (FoldMskICmp_Mask_AllZeroes | FoldMskICmp_AMask_Mixed)); - } - else if (ACst != 0 && CCst != 0 && - ConstantExpr::getAnd(ACst, CCst) == CCst) { + } else if (ACst != 0 && CCst != 0 && + ConstantExpr::getAnd(ACst, CCst) == CCst) { result |= (icmp_eq ? FoldMskICmp_AMask_Mixed : FoldMskICmp_AMask_NotMixed); } - if (B == C) - { + 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_BMask_NotMixed) : (FoldMskICmp_Mask_AllZeroes | FoldMskICmp_BMask_Mixed)); - } - else if (BCst != 0 && CCst != 0 && - ConstantExpr::getAnd(BCst, CCst) == CCst) { + } else if (BCst != 0 && CCst != 0 && + ConstantExpr::getAnd(BCst, CCst) == CCst) { result |= (icmp_eq ? FoldMskICmp_BMask_Mixed : FoldMskICmp_BMask_NotMixed); } @@ -531,7 +528,7 @@ static bool decomposeBitTestICmp(const ICmpInst *I, ICmpInst::Predicate &Pred, /// 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, +static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A, Value*& B, Value*& C, Value*& D, Value*& E, ICmpInst *LHS, ICmpInst *RHS, @@ -542,10 +539,10 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A, 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, + // 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 + // 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); @@ -610,14 +607,11 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A, if (L11 == A) { B = L12; C = L2; - } - else if (L12 == A) { + } else if (L12 == A) { B = L11; C = L2; - } - else if (L21 == A) { + } else if (L21 == A) { B = L22; C = L1; - } - else if (L22 == A) { + } else if (L22 == A) { B = L21; C = L1; } @@ -643,32 +637,32 @@ static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, mask >>= 1; // treat "Not"-states as normal states if (mask & FoldMskICmp_Mask_AllZeroes) { - // (icmp eq (A & B), 0) & (icmp eq (A & D), 0) + // (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) + // (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); } - else if (mask & FoldMskICmp_BMask_AllOnes) { - // (icmp eq (A & B), B) & (icmp eq (A & D), D) + 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); - } - else if (mask & FoldMskICmp_AMask_AllOnes) { - // (icmp eq (A & B), A) & (icmp eq (A & D), A) + } + 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* newAnd = Builder->CreateAnd(A, newAnd1); return Builder->CreateICmp(NEWCC, newAnd, A); } - else if (mask & FoldMskICmp_BMask_Mixed) { - // (icmp eq (A & B), C) & (icmp eq (A & D), E) + 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 @@ -680,7 +674,7 @@ static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, ConstantInt *DCst = dyn_cast<ConstantInt>(D); if (DCst == 0) return 0; // we can't simply use C and E, because we might actually handle - // (icmp ne (A & B), B) & (icmp eq (A & D), D) + // (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); @@ -727,13 +721,13 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // handle (roughly): (icmp eq (A & B), C) & (icmp eq (A & D), E) if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_EQ, Builder)) 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 == 0 || RHSCst == 0) return 0; - + 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 @@ -742,7 +736,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { Value *NewOr = Builder->CreateOr(Val, Val2); return Builder->CreateICmp(LHSCC, NewOr, LHSCst); } - + // (icmp eq A, 0) & (icmp eq B, 0) --> (icmp eq (A|B), 0) if (LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero()) { Value *NewOr = Builder->CreateOr(Val, Val2); @@ -759,14 +753,13 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { ConstantInt *AndCst, *SmallCst = 0, *BigCst = 0; // (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; - } - // (and x, CA) == C2 & (trunc x) == C1 - else if (match(Val, m_Trunc(m_Value(V))) && - match(Val2, m_And(m_Specific(V), m_ConstantInt(AndCst)))) { + } else if (match(Val, m_Trunc(m_Value(V))) && + match(Val2, m_And(m_Specific(V), m_ConstantInt(AndCst)))) { SmallCst = LHSCst; BigCst = RHSCst; } @@ -789,7 +782,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // From here on, we only handle: // (icmp1 A, C1) & (icmp2 A, C2) --> something simpler. if (Val != Val2) return 0; - + // 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 || @@ -799,9 +792,9 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // Make a constant range that's the intersection of the two icmp ranges. // If the intersection is empty, we know that the result is false. - ConstantRange LHSRange = + ConstantRange LHSRange = ConstantRange::makeICmpRegion(LHSCC, LHSCst->getValue()); - ConstantRange RHSRange = + ConstantRange RHSRange = ConstantRange::makeICmpRegion(RHSCC, RHSCst->getValue()); if (LHSRange.intersectWith(RHSRange).isEmptySet()) @@ -810,16 +803,16 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // We can't fold (ugt x, C) & (sgt x, C2). if (!PredicatesFoldable(LHSCC, RHSCC)) return 0; - + // Ensure that the larger constant is on the RHS. bool ShouldSwap; if (CmpInst::isSigned(LHSCC) || - (ICmpInst::isEquality(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); @@ -829,8 +822,8 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // 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 + // 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?"); @@ -932,7 +925,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) { } break; } - + return 0; } @@ -951,7 +944,7 @@ Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { return ConstantInt::getFalse(LHS->getContext()); 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)) && @@ -959,18 +952,18 @@ Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0)); return 0; } - + 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); } - + if (Op0LHS == Op1LHS && Op0RHS == Op1RHS) { // Simplify (fcmp cc0 x, y) & (fcmp cc1 x, y). if (Op0CC == Op1CC) @@ -981,7 +974,7 @@ Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { return RHS; if (Op1CC == FCmpInst::FCMP_TRUE) return LHS; - + bool Op0Ordered; bool Op1Ordered; unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered); @@ -1001,7 +994,7 @@ Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { return LHS; if (Op0Ordered && (Op0Ordered == Op1Ordered)) return RHS; - + // uno && oeq -> uno && (ord && eq) -> false if (!Op0Ordered) return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0); @@ -1025,10 +1018,10 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { if (Value *V = SimplifyUsingDistributiveLaws(I)) return ReplaceInstUsesWith(I, V); - // See if we can simplify any instructions used by the instruction whose sole + // 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; + return &I; if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) { const APInt &AndRHSMask = AndRHS->getValue(); @@ -1043,7 +1036,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { 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)) { // Not masking anything out for the LHS, move to RHS. @@ -1103,12 +1096,12 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { } 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. { @@ -1116,7 +1109,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { 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 + // 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()); @@ -1143,7 +1136,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { I.getName()+".demorgan"); return BinaryOperator::CreateNot(Or); } - + { Value *A = 0, *B = 0, *C = 0, *D = 0; // (A|B) & ~(A&B) -> A^B @@ -1151,13 +1144,13 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { 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; @@ -1193,19 +1186,19 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { match(Op1, m_Or(m_Value(A), m_Not(m_Specific(Op0))))) return BinaryOperator::CreateAnd(A, Op0); } - + if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1)) if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0)) if (Value *Res = FoldAndOfICmps(LHS, RHS)) return ReplaceInstUsesWith(I, Res); - + // 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); - - + + // fold (and (cast A), (cast B)) -> (cast (and A, B)) if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) if (CastInst *Op1C = dyn_cast<CastInst>(Op1)) { @@ -1214,21 +1207,21 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { SrcTy == Op1C->getOperand(0)->getType() && SrcTy->isIntOrIntVectorTy()) { Value *Op0COp = Op0C->getOperand(0), *Op1COp = Op1C->getOperand(0); - + // Only do this if the casts both really cause code to be generated. if (ShouldOptimizeCast(Op0C->getOpcode(), Op0COp, I.getType()) && ShouldOptimizeCast(Op1C->getOpcode(), Op1COp, I.getType())) { Value *NewOp = Builder->CreateAnd(Op0COp, Op1COp, I.getName()); return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType()); } - + // If this is and(cast(icmp), cast(icmp)), try to fold this even if the // cast is otherwise not optimizable. This happens for vector sexts. if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1COp)) if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0COp)) if (Value *Res = FoldAndOfICmps(LHS, RHS)) return CastInst::Create(Op0C->getOpcode(), Res, I.getType()); - + // If this is and(cast(fcmp), cast(fcmp)), try to fold this even if the // cast is otherwise not optimizable. This happens for vector sexts. if (FCmpInst *RHS = dyn_cast<FCmpInst>(Op1COp)) @@ -1237,21 +1230,49 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) { return CastInst::Create(Op0C->getOpcode(), Res, I.getType()); } } - + // (X >> Z) & (Y >> Z) -> (X&Y) >> Z for all shifts. if (BinaryOperator *SI1 = dyn_cast<BinaryOperator>(Op1)) { if (BinaryOperator *SI0 = dyn_cast<BinaryOperator>(Op0)) - if (SI0->isShift() && SI0->getOpcode() == SI1->getOpcode() && + if (SI0->isShift() && SI0->getOpcode() == SI1->getOpcode() && SI0->getOperand(1) == SI1->getOperand(1) && (SI0->hasOneUse() || SI1->hasOneUse())) { Value *NewOp = Builder->CreateAnd(SI0->getOperand(0), SI1->getOperand(0), SI0->getName()); - return BinaryOperator::Create(SI1->getOpcode(), NewOp, + return BinaryOperator::Create(SI1->getOpcode(), NewOp, SI1->getOperand(1)); } } + { + Value *X = 0; + bool OpsSwapped = false; + // Canonicalize SExt or Not to the LHS + if (match(Op1, m_SExt(m_Value())) || + match(Op1, m_Not(m_Value()))) { + std::swap(Op0, Op1); + OpsSwapped = true; + } + + // Fold (and (sext bool to A), B) --> (select bool, B, 0) + 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); + } + + if (OpsSwapped) + std::swap(Op0, Op1); + } + return Changed ? &I : 0; } @@ -1288,11 +1309,11 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, CollectBSwapParts(I->getOperand(1), OverallLeftShift, ByteMask, ByteValues); } - + // If this is a logical shift by a constant multiple of 8, recurse with // OverallLeftShift and ByteMask adjusted. if (I->isLogicalShift() && isa<ConstantInt>(I->getOperand(1))) { - unsigned ShAmt = + unsigned ShAmt = cast<ConstantInt>(I->getOperand(1))->getLimitedValue(~0U); // Ensure the shift amount is defined and of a byte value. if ((ShAmt & 7) || (ShAmt > 8*ByteValues.size())) @@ -1313,7 +1334,7 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, if (OverallLeftShift >= (int)ByteValues.size()) return true; if (OverallLeftShift <= -(int)ByteValues.size()) return true; - return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask, + return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask, ByteValues); } @@ -1325,20 +1346,20 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, unsigned NumBytes = ByteValues.size(); APInt Byte(I->getType()->getPrimitiveSizeInBits(), 255); const APInt &AndMask = cast<ConstantInt>(I->getOperand(1))->getValue(); - + for (unsigned i = 0; i != NumBytes; ++i, Byte <<= 8) { // If this byte is masked out by a later operation, we don't care what // the and mask is. if ((ByteMask & (1 << i)) == 0) continue; - + // If the AndMask is all zeros for this byte, clear the bit. APInt MaskB = AndMask & Byte; if (MaskB == 0) { ByteMask &= ~(1U << i); continue; } - + // If the AndMask is not all ones for this byte, it's not a bytezap. if (MaskB != Byte) return true; @@ -1346,11 +1367,11 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, // Otherwise, this byte is kept. } - return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask, + return CollectBSwapParts(I->getOperand(0), OverallLeftShift, ByteMask, ByteValues); } } - + // Okay, we got to something that isn't a shift, 'or' or 'and'. This must be // the input value to the bswap. Some observations: 1) if more than one byte // is demanded from this input, then it could not be successfully assembled @@ -1358,7 +1379,7 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, // their ultimate destination. if (!isPowerOf2_32(ByteMask)) return true; unsigned InputByteNo = CountTrailingZeros_32(ByteMask); - + // 2) The input and ultimate destinations must line up: if byte 3 of an i32 // is demanded, it needs to go into byte 0 of the result. This means that the // byte needs to be shifted until it lands in the right byte bucket. The @@ -1368,7 +1389,7 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, unsigned DestByteNo = InputByteNo + OverallLeftShift; if (ByteValues.size()-1-DestByteNo != InputByteNo) return true; - + // If the destination byte value is already defined, the values are or'd // together, which isn't a bswap (unless it's an or of the same bits). if (ByteValues[DestByteNo] && ByteValues[DestByteNo] != V) @@ -1381,25 +1402,25 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask, /// If so, insert the new bswap intrinsic and return it. Instruction *InstCombiner::MatchBSwap(BinaryOperator &I) { IntegerType *ITy = dyn_cast<IntegerType>(I.getType()); - if (!ITy || ITy->getBitWidth() % 16 || + if (!ITy || ITy->getBitWidth() % 16 || // ByteMask only allows up to 32-byte values. - ITy->getBitWidth() > 32*8) + ITy->getBitWidth() > 32*8) return 0; // Can only bswap pairs of bytes. Can't do vectors. - + /// ByteValues - For each byte of the result, we keep track of which value /// defines each byte. SmallVector<Value*, 8> ByteValues; ByteValues.resize(ITy->getBitWidth()/8); - + // Try to find all the pieces corresponding to the bswap. uint32_t ByteMask = ~0U >> (32-ByteValues.size()); if (CollectBSwapParts(&I, 0, ByteMask, ByteValues)) return 0; - + // Check to see if all of the bytes come from the same value. Value *V = ByteValues[0]; if (V == 0) return 0; // Didn't find a byte? Must be zero. - + // Check to make sure that all of the bytes come from the same value. for (unsigned i = 1, e = ByteValues.size(); i != e; ++i) if (ByteValues[i] != V) @@ -1425,7 +1446,7 @@ static Instruction *MatchSelectFromAndOr(Value *A, Value *B, return SelectInst::Create(Cond, C, B); if (match(D, m_SExt(m_Not(m_Specific(Cond))))) return SelectInst::Create(Cond, C, B); - + // ((cond?-1:0)&C) | ((cond?0:-1)&D) -> cond ? C : D. if (match(B, m_Not(m_SExt(m_Specific(Cond))))) return SelectInst::Create(Cond, C, D); @@ -1483,33 +1504,33 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) { // From here on, we only handle: // (icmp1 A, C1) | (icmp2 A, C2) --> something simpler. if (Val != Val2) return 0; - + // 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 0; - + // We can't fold (ugt x, C) | (sgt x, C2). if (!PredicatesFoldable(LHSCC, RHSCC)) return 0; - + // Ensure that the larger constant is on the RHS. bool ShouldSwap; if (CmpInst::isSigned(LHSCC) || - (ICmpInst::isEquality(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 @@ -1531,6 +1552,20 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) { AddCST = ConstantExpr::getSub(AddOne(RHSCst), LHSCst); return Builder->CreateICmpULT(Add, AddCST); } + + if (LHS->getOperand(0) == RHS->getOperand(0)) { + // if LHSCst and RHSCst differ only by one bit: + // (A == C1 || A == C2) -> (A & ~(C1 ^ C2)) == C1 + assert(LHSCst->getValue().ule(LHSCst->getValue())); + + APInt Xor = LHSCst->getValue() ^ RHSCst->getValue(); + if (Xor.isPowerOf2()) { + Value *NegCst = Builder->getInt(~Xor); + Value *And = Builder->CreateAnd(LHS->getOperand(0), NegCst); + return Builder->CreateICmp(ICmpInst::ICMP_EQ, And, LHSCst); + } + } + 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 @@ -1632,7 +1667,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) { /// function. Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { if (LHS->getPredicate() == FCmpInst::FCMP_UNO && - RHS->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))) { @@ -1640,25 +1675,25 @@ Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { // true. if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN()) return ConstantInt::getTrue(LHS->getContext()); - + // 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 0; } - + 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); @@ -1692,7 +1727,7 @@ Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) { /// ((A | B) & C1) | (B & C2) /// /// into: -/// +/// /// (A & C1) | B /// /// when the XOR of the two constants is "all ones" (-1). @@ -1727,7 +1762,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { if (Value *V = SimplifyUsingDistributiveLaws(I)) return ReplaceInstUsesWith(I, V); - // See if we can simplify any instructions used by the instruction whose sole + // 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; @@ -1741,7 +1776,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { Op0->hasOneUse()) { Value *Or = Builder->CreateOr(X, RHS); Or->takeName(Op0); - return BinaryOperator::CreateAnd(Or, + return BinaryOperator::CreateAnd(Or, ConstantInt::get(I.getContext(), RHS->getValue() | C1->getValue())); } @@ -1778,7 +1813,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { if (Instruction *BSwap = MatchBSwap(I)) return BSwap; } - + // (X^C)|Y -> (X|Y)^C iff Y&C == 0 if (Op0->hasOneUse() && match(Op0, m_Xor(m_Value(A), m_ConstantInt(C1))) && @@ -1827,7 +1862,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { return ReplaceInstUsesWith(I, B); } } - + if ((C1->getValue() & C2->getValue()) == 0) { // ((V | N) & C1) | (V & C2) --> (V|N) & (C1|C2) // iff (C1&C2) == 0 and (N&~C1) == 0 @@ -1844,7 +1879,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { return BinaryOperator::CreateAnd(B, ConstantInt::get(B->getContext(), 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 = 0, *C4 = 0; @@ -1904,16 +1939,16 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { if (Ret) return Ret; } } - + // (X >> Z) | (Y >> Z) -> (X|Y) >> Z for all shifts. if (BinaryOperator *SI1 = dyn_cast<BinaryOperator>(Op1)) { if (BinaryOperator *SI0 = dyn_cast<BinaryOperator>(Op0)) - if (SI0->isShift() && SI0->getOpcode() == SI1->getOpcode() && + if (SI0->isShift() && SI0->getOpcode() == SI1->getOpcode() && SI0->getOperand(1) == SI1->getOperand(1) && (SI0->hasOneUse() || SI1->hasOneUse())) { Value *NewOp = Builder->CreateOr(SI0->getOperand(0), SI1->getOperand(0), SI0->getName()); - return BinaryOperator::Create(SI1->getOpcode(), NewOp, + return BinaryOperator::Create(SI1->getOpcode(), NewOp, SI1->getOperand(1)); } } @@ -1975,13 +2010,13 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0))) if (Value *Res = FoldOrOfICmps(LHS, RHS)) return ReplaceInstUsesWith(I, Res); - + // (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); - + // fold (or (cast A), (cast B)) -> (cast (or A, B)) if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) { CastInst *Op1C = dyn_cast<CastInst>(Op1); @@ -1999,14 +2034,14 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { Value *NewOp = Builder->CreateOr(Op0COp, Op1COp, I.getName()); return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType()); } - + // If this is or(cast(icmp), cast(icmp)), try to fold this even if the // cast is otherwise not optimizable. This happens for vector sexts. if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1COp)) if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0COp)) if (Value *Res = FoldOrOfICmps(LHS, RHS)) return CastInst::Create(Op0C->getOpcode(), Res, I.getType()); - + // If this is or(cast(fcmp), cast(fcmp)), try to fold this even if the // cast is otherwise not optimizable. This happens for vector sexts. if (FCmpInst *RHS = dyn_cast<FCmpInst>(Op1COp)) @@ -2035,7 +2070,21 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) { 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 = 0, *Y = 0; + 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 : 0; } @@ -2050,7 +2099,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { if (Value *V = SimplifyUsingDistributiveLaws(I)) return ReplaceInstUsesWith(I, V); - // See if we can simplify any instructions used by the instruction whose sole + // 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; @@ -2058,7 +2107,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { // Is this a ~ operation? if (Value *NotOp = dyn_castNotVal(&I)) { if (BinaryOperator *Op0I = dyn_cast<BinaryOperator>(NotOp)) { - if (Op0I->getOpcode() == Instruction::And || + 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 @@ -2072,10 +2121,10 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { 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)) && + if (isFreeToInvert(Op0I->getOperand(0)) && isFreeToInvert(Op0I->getOperand(1))) { Value *NotX = Builder->CreateNot(Op0I->getOperand(0), "notlhs"); @@ -2093,8 +2142,8 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { } } } - - + + if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) { if (RHS->isOne() && Op0->hasOneUse()) // xor (cmp A, B), true = not (cmp A, B) = !cmp A, B @@ -2109,7 +2158,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { if (CI->hasOneUse() && Op0C->hasOneUse()) { Instruction::CastOps Opcode = Op0C->getOpcode(); if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) && - (RHS == ConstantExpr::getCast(Opcode, + (RHS == ConstantExpr::getCast(Opcode, ConstantInt::getTrue(I.getContext()), Op0C->getDestTy()))) { CI->setPredicate(CI->getInversePredicate()); @@ -2128,7 +2177,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { 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 @@ -2152,13 +2201,34 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { // 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, + 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); + } } } } @@ -2184,7 +2254,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { I.swapOperands(); // Simplified below. std::swap(Op0, Op1); } - } else if (match(Op1I, m_And(m_Value(A), m_Value(B))) && + } 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(); @@ -2196,7 +2266,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { } } } - + BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0); if (Op0I) { Value *A, *B; @@ -2206,7 +2276,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { 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))) && + } 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); @@ -2216,31 +2286,31 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { } } } - + // (X >> Z) ^ (Y >> Z) -> (X^Y) >> Z for all shifts. - if (Op0I && Op1I && Op0I->isShift() && - Op0I->getOpcode() == Op1I->getOpcode() && + if (Op0I && Op1I && Op0I->isShift() && + Op0I->getOpcode() == Op1I->getOpcode() && Op0I->getOperand(1) == Op1I->getOperand(1) && (Op0I->hasOneUse() || Op1I->hasOneUse())) { Value *NewOp = Builder->CreateXor(Op0I->getOperand(0), Op1I->getOperand(0), Op0I->getName()); - return BinaryOperator::Create(Op1I->getOpcode(), NewOp, + return BinaryOperator::Create(Op1I->getOpcode(), NewOp, Op1I->getOperand(1)); } - + 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)) + 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)) + if ((A == C && B == D) || (A == D && B == C)) return BinaryOperator::CreateXor(A, B); } } @@ -2257,7 +2327,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1); unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS); bool isSigned = LHS->isSigned() || RHS->isSigned(); - return ReplaceInstUsesWith(I, + return ReplaceInstUsesWith(I, getNewICmpValue(isSigned, Code, Op0, Op1, Builder)); } @@ -2270,9 +2340,9 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) { Type *SrcTy = Op0C->getOperand(0)->getType(); if (SrcTy == Op1C->getOperand(0)->getType() && SrcTy->isIntegerTy() && // Only do this if the casts both really cause code to be generated. - ShouldOptimizeCast(Op0C->getOpcode(), Op0C->getOperand(0), + ShouldOptimizeCast(Op0C->getOpcode(), Op0C->getOperand(0), I.getType()) && - ShouldOptimizeCast(Op1C->getOpcode(), Op1C->getOperand(0), + ShouldOptimizeCast(Op1C->getOpcode(), Op1C->getOperand(0), I.getType())) { Value *NewOp = Builder->CreateXor(Op0C->getOperand(0), Op1C->getOperand(0), I.getName()); |
