//
//===----------------------------------------------------------------------===//
-#include "InstCombine.h"
+#include "InstCombineInternal.h"
#include "llvm/Analysis/InstructionSimplify.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Intrinsics.h"
#define DEBUG_TYPE "instcombine"
-/// isFreeToInvert - Return true if the specified value is free to invert (apply
-/// ~ to). This happens in cases where the ~ can be eliminated.
-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;
-}
-
static inline Value *dyn_castNotVal(Value *V) {
// If this is not(not(x)) don't return that this is a not: we want the two
// not's to be folded first.
if (BinaryOperator::isNot(V)) {
Value *Operand = BinaryOperator::getNotArgument(V);
- if (!isFreeToInvert(Operand))
+ if (!IsFreeToInvert(Operand, Operand->hasOneUse()))
return Operand;
}
return nullptr;
}
-/// getFCmpCode - Similar to getICmpCode but for FCmpInst. This encodes a fcmp
-/// predicate into a three bit mask. It also returns whether it is an ordered
-/// predicate by reference.
+/// Similar to getICmpCode but for FCmpInst. This encodes a fcmp predicate into
+/// a three bit mask. It also returns whether it is an ordered predicate by
+/// reference.
static unsigned getFCmpCode(FCmpInst::Predicate CC, bool &isOrdered) {
isOrdered = false;
switch (CC) {
}
}
-/// getNewICmpValue - This is the complement of getICmpCode, which turns an
-/// opcode and two operands into either a constant true or false, or a brand
-/// new ICmp instruction. The sign is passed in to determine which kind
-/// of predicate to use in the new icmp instruction.
+/// This is the complement of getICmpCode, which turns an opcode and two
+/// operands into either a constant true or false, or a brand new ICmp
+/// instruction. The sign is passed in to determine which kind of predicate to
+/// use in the new icmp instruction.
static Value *getNewICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
InstCombiner::BuilderTy *Builder) {
ICmpInst::Predicate NewPred;
return Builder->CreateICmp(NewPred, LHS, RHS);
}
-/// getFCmpValue - This is the complement of getFCmpCode, which turns an
-/// opcode and two operands into either a FCmp instruction. isordered is passed
-/// in to determine which kind of predicate to use in the new fcmp instruction.
+/// This is the complement of getFCmpCode, which turns an opcode and two
+/// operands into either a FCmp instruction. isordered is passed in to determine
+/// which kind of predicate to use in the new fcmp instruction.
static Value *getFCmpValue(bool isordered, unsigned code,
Value *LHS, Value *RHS,
InstCombiner::BuilderTy *Builder) {
case 5: Pred = isordered ? FCmpInst::FCMP_ONE : FCmpInst::FCMP_UNE; break;
case 6: Pred = isordered ? FCmpInst::FCMP_OLE : FCmpInst::FCMP_ULE; break;
case 7:
- if (!isordered) return ConstantInt::getTrue(LHS->getContext());
+ if (!isordered)
+ return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
Pred = FCmpInst::FCMP_ORD; break;
}
return Builder->CreateFCmp(Pred, LHS, RHS);
}
-// OptAndOp - This handles expressions of the form ((val OP C1) & C2). Where
-// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
-// guaranteed to be a binary operator.
+/// \brief Transform BITWISE_OP(BSWAP(A),BSWAP(B)) to BSWAP(BITWISE_OP(A, B))
+/// \param I Binary operator to transform.
+/// \return Pointer to node that must replace the original binary operator, or
+/// null pointer if no transformation was made.
+Value *InstCombiner::SimplifyBSwap(BinaryOperator &I) {
+ IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
+
+ // Can't do vectors.
+ if (I.getType()->isVectorTy()) return nullptr;
+
+ // Can only do bitwise ops.
+ unsigned Op = I.getOpcode();
+ if (Op != Instruction::And && Op != Instruction::Or &&
+ Op != Instruction::Xor)
+ return nullptr;
+
+ Value *OldLHS = I.getOperand(0);
+ Value *OldRHS = I.getOperand(1);
+ ConstantInt *ConstLHS = dyn_cast<ConstantInt>(OldLHS);
+ ConstantInt *ConstRHS = dyn_cast<ConstantInt>(OldRHS);
+ IntrinsicInst *IntrLHS = dyn_cast<IntrinsicInst>(OldLHS);
+ IntrinsicInst *IntrRHS = dyn_cast<IntrinsicInst>(OldRHS);
+ bool IsBswapLHS = (IntrLHS && IntrLHS->getIntrinsicID() == Intrinsic::bswap);
+ bool IsBswapRHS = (IntrRHS && IntrRHS->getIntrinsicID() == Intrinsic::bswap);
+
+ if (!IsBswapLHS && !IsBswapRHS)
+ return nullptr;
+
+ if (!IsBswapLHS && !ConstLHS)
+ return nullptr;
+
+ if (!IsBswapRHS && !ConstRHS)
+ return nullptr;
+
+ /// OP( BSWAP(x), BSWAP(y) ) -> BSWAP( OP(x, y) )
+ /// OP( BSWAP(x), CONSTANT ) -> BSWAP( OP(x, BSWAP(CONSTANT) ) )
+ Value *NewLHS = IsBswapLHS ? IntrLHS->getOperand(0) :
+ Builder->getInt(ConstLHS->getValue().byteSwap());
+
+ Value *NewRHS = IsBswapRHS ? IntrRHS->getOperand(0) :
+ Builder->getInt(ConstRHS->getValue().byteSwap());
+
+ Value *BinOp = nullptr;
+ if (Op == Instruction::And)
+ BinOp = Builder->CreateAnd(NewLHS, NewRHS);
+ else if (Op == Instruction::Or)
+ BinOp = Builder->CreateOr(NewLHS, NewRHS);
+ else //if (Op == Instruction::Xor)
+ BinOp = Builder->CreateXor(NewLHS, NewRHS);
+
+ Module *M = I.getParent()->getParent()->getParent();
+ Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, ITy);
+ return Builder->CreateCall(F, BinOp);
+}
+
+/// This handles expressions of the form ((val OP C1) & C2). Where
+/// the Op parameter is 'OP', OpRHS is 'C1', and AndRHS is 'C2'. Op is
+/// guaranteed to be a binary operator.
Instruction *InstCombiner::OptAndOp(Instruction *Op,
ConstantInt *OpRHS,
ConstantInt *AndRHS,
return Builder->CreateICmpUGT(Add, LowerBound);
}
-// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s with
-// any number of 0s on either side. The 1s are allowed to wrap from LSB to
-// MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
-// not, since all 1s are not contiguous.
+/// Returns true iff Val consists of one contiguous run of 1s with any number
+/// of 0s on either side. The 1s are allowed to wrap from LSB to MSB,
+/// so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
+/// not, since all 1s are not contiguous.
static bool isRunOfOnes(ConstantInt *Val, uint32_t &MB, uint32_t &ME) {
const APInt& V = Val->getValue();
uint32_t BitWidth = Val->getType()->getBitWidth();
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:
+/// 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
if (isRunOfOnes(Mask, MB, ME)) { // begin/end bit of run, inclusive
uint32_t BitWidth = cast<IntegerType>(RHS->getType())->getBitWidth();
APInt Mask(APInt::getLowBitsSet(BitWidth, MB-1));
- if (MaskedValueIsZero(RHS, Mask))
+ if (MaskedValueIsZero(RHS, Mask, 0, &I))
break;
}
}
FoldMskICmp_BMask_NotMixed = 512
};
-/// return the set of pattern classes (from MaskedICmpType)
-/// that (icmp SCC (A & B), C) satisfies
+/// 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)
{
return NewMask;
}
-/// decomposeBitTestICmp - Decompose an icmp into the form ((X & Y) pred Z)
-/// if possible. The returned predicate is either == or !=. Returns false if
+/// Decompose an icmp into the form ((X & Y) pred Z) if possible.
+/// The returned predicate is either == or !=. Returns false if
/// decomposition fails.
static bool decomposeBitTestICmp(const ICmpInst *I, ICmpInst::Predicate &Pred,
Value *&X, Value *&Y, Value *&Z) {
return true;
}
-/// foldLogOpOfMaskedICmpsHelper:
-/// handle (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
-/// return the set of pattern classes (from MaskedICmpType)
-/// that both LHS and RHS satisfy
+/// 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,
unsigned right_type = getTypeOfMaskedICmp(A, D, E, RHSCC);
return left_type & right_type;
}
-/// foldLogOpOfMaskedICmps:
-/// 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) {
+
+/// 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,
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);
+ 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());
+ 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);
+ 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* newAnd = Builder->CreateAnd(A, newAnd1);
+ Value *newAnd1 = Builder->CreateAnd(B, D);
+ Value *newAnd = Builder->CreateAnd(A, newAnd1);
return Builder->CreateICmp(NEWCC, newAnd, A);
}
// with B and D, having a single bit set
ConstantInt *CCst = dyn_cast<ConstantInt>(C);
if (!CCst) return nullptr;
- if (LHSCC != NEWCC)
- CCst = dyn_cast<ConstantInt>( ConstantExpr::getXor(BCst, CCst) );
ConstantInt *ECst = dyn_cast<ConstantInt>(E);
if (!ECst) return nullptr;
+ if (LHSCC != NEWCC)
+ CCst = cast<ConstantInt>(ConstantExpr::getXor(BCst, CCst));
if (RHSCC != NEWCC)
- ECst = dyn_cast<ConstantInt>( ConstantExpr::getXor(DCst, ECst) );
- ConstantInt* MCst = dyn_cast<ConstantInt>(
- ConstantExpr::getAnd(ConstantExpr::getAnd(BCst, DCst),
- ConstantExpr::getXor(CCst, ECst)) );
+ ECst = cast<ConstantInt>(ConstantExpr::getXor(DCst, ECst));
// if there is a conflict we should actually return a false for the
// whole construct
- if (!MCst->isZero())
- return nullptr;
+ 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 nullptr;
}
-/// FoldAndOfICmps - Fold (icmp)&(icmp) if possible.
+/// 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();
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));
// 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::makeICmpRegion(LHSCC, LHSCst->getValue());
+ ConstantRange::makeAllowedICmpRegion(LHSCC, LHSCst->getValue());
ConstantRange RHSRange =
- ConstantRange::makeICmpRegion(RHSCC, RHSCst->getValue());
+ ConstantRange::makeAllowedICmpRegion(RHSCC, RHSCst->getValue());
if (LHSRange.intersectWith(RHSRange).isEmptySet())
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
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, AddOne(LHSCst), RHSCst, 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 nullptr;
}
-/// FoldAndOfFCmps - Optimize (fcmp)&(fcmp). NOTE: Unlike the rest of
-/// instcombine, this returns a Value which should already be inserted into the
-/// function.
+/// 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) {
if (LHS->getPredicate() == FCmpInst::FCMP_ORD &&
RHS->getPredicate() == FCmpInst::FCMP_ORD) {
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");
+
+ 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()) {
+ // Flip the logic operation.
+ if (Opcode == Instruction::And)
+ Opcode = Instruction::Or;
+ else
+ Opcode = Instruction::And;
+ Value *LogicOp = Builder->CreateBinOp(Opcode, Op0NotVal, Op1NotVal,
+ I.getName() + ".demorgan");
+ return BinaryOperator::CreateNot(LogicOp);
+ }
+
+ 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))
+ if (Value *V = SimplifyAndInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A|B)&(A|C) -> A|(B&C) etc
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();
if (!Op0I->hasOneUse()) break;
APInt NotAndRHS(~AndRHSMask);
- if (MaskedValueIsZero(Op0LHS, NotAndRHS)) {
+ 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)) {
+ MaskedValueIsZero(Op0RHS, NotAndRHS, 0, &I)) {
// Not masking anything out for the RHS, move to LHS.
Value *NewLHS = Builder->CreateAnd(Op0LHS, AndRHS,
Op0LHS->getName()+".masked");
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 Zeros = AndRHSMask.countLeadingZeros();
APInt Mask = APInt::getLowBitsSet(BitWidth, BitWidth - Zeros);
- if (MaskedValueIsZero(Op0LHS, Mask)) {
+ if (MaskedValueIsZero(Op0LHS, Mask, 0, &I)) {
Value *NewNeg = Builder->CreateNeg(Op0RHS);
return BinaryOperator::CreateAnd(NewNeg, AndRHS);
}
return NV;
}
-
- // (~A & ~B) == (~(A | B)) - De Morgan's Law
- if (Value *Op0NotVal = dyn_castNotVal(Op0))
- if (Value *Op1NotVal = dyn_castNotVal(Op1))
- if (Op0->hasOneUse() && Op1->hasOneUse()) {
- Value *Or = Builder->CreateOr(Op0NotVal, Op1NotVal,
- I.getName()+".demorgan");
- return BinaryOperator::CreateNot(Or);
- }
+ if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
+ return DeMorgan;
{
Value *A = nullptr, *B = nullptr, *C = nullptr, *D = nullptr;
return Changed ? &I : nullptr;
}
-/// CollectBSwapParts - Analyze the specified subexpression and see if it is
-/// capable of providing pieces of a bswap. The subexpression provides pieces
-/// of a bswap if it is proven that each of the non-zero bytes in the output of
-/// the expression came from the corresponding "byte swapped" byte in some other
-/// value. For example, if the current subexpression is "(shl i32 %X, 24)" then
+/// Analyze the specified subexpression and see if it is capable of providing
+/// pieces of a bswap. The subexpression provides pieces of a bswap if it is
+/// proven that each of the non-zero bytes in the output of the expression came
+/// from the corresponding "byte swapped" byte in some other value.
+/// For example, if the current subexpression is "(shl i32 %X, 24)" then
/// we know that the expression deposits the low byte of %X into the high byte
/// of the bswap result and that all other bytes are zero. This expression is
/// accepted, the high byte of ByteValues is set to X to indicate a correct
return false;
}
-/// MatchBSwap - Given an OR instruction, check to see if this is a bswap idiom.
+/// Given an OR instruction, check to see if this is a bswap idiom.
/// If so, insert the new bswap intrinsic and return it.
Instruction *InstCombiner::MatchBSwap(BinaryOperator &I) {
IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
return CallInst::Create(F, V);
}
-/// MatchSelectFromAndOr - We have an expression of the form (A&C)|(B&D). Check
-/// If A is (cond?-1:0) and either B or D is ~(cond?-1,0) or (cond?0,-1), then
-/// we can simplify this expression to "cond ? C : D or B".
+/// We have an expression of the form (A&C)|(B&D). Check if A is (cond?-1:0)
+/// and either B or D is ~(cond?-1,0) or (cond?0,-1), then we can simplify this
+/// expression to "cond ? C : D or B".
static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
Value *C, Value *D) {
// If A is not a select of -1/0, this cannot match.
return nullptr;
}
-/// FoldOrOfICmps - Fold (icmp)|(icmp) if possible.
-Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
+/// 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)
Value *Mask = nullptr;
Value *Masked = nullptr;
if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
- isKnownToBeAPowerOfTwo(LAnd->getOperand(1)) &&
- isKnownToBeAPowerOfTwo(RAnd->getOperand(1))) {
+ 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)) &&
- isKnownToBeAPowerOfTwo(RAnd->getOperand(0))) {
+ 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);
}
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;
return nullptr;
}
-/// FoldOrOfFCmps - Optimize (fcmp)|(fcmp). NOTE: Unlike the rest of
-/// instcombine, this returns a Value which should already be inserted into the
-/// function.
+/// 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) {
if (LHS->getPredicate() == FCmpInst::FCMP_UNO &&
RHS->getPredicate() == FCmpInst::FCMP_UNO &&
return nullptr;
}
-/// FoldOrWithConstants - This helper function folds:
+/// This helper function folds:
///
/// ((A | B) & C1) | (B & C2)
///
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
- if (Value *V = SimplifyOrInst(Op0, Op1, DL))
+ if (Value *V = SimplifyOrInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A&B)|(A&C) -> A&(B|C) etc
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)
// (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())) {
+ 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())) {
+ MaskedValueIsZero(Op0, C1->getValue(), 0, &I)) {
Value *NOr = Builder->CreateOr(A, Op0);
NOr->takeName(Op0);
return BinaryOperator::CreateXor(NOr, C1);
// ((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())) || // (V|N)
- (V2 == B && MaskedValueIsZero(V1, ~C1->getValue())))) // (N|V)
+ ((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())) || // (V|N)
- (V2 == A && MaskedValueIsZero(V1, ~C2->getValue())))) // (N|V)
+ ((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()));
if (match(Op0, m_And(m_Or(m_Specific(Op1), m_Value(C)), m_Value(A))))
return BinaryOperator::CreateOr(Op1, Builder->CreateAnd(A, C));
- // (~A | ~B) == (~(A & B)) - De Morgan's Law
- if (Value *Op0NotVal = dyn_castNotVal(Op0))
- if (Value *Op1NotVal = dyn_castNotVal(Op1))
- if (Op0->hasOneUse() && Op1->hasOneUse()) {
- Value *And = Builder->CreateAnd(Op0NotVal, Op1NotVal,
- I.getName()+".demorgan");
- return BinaryOperator::CreateNot(And);
- }
+ if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
+ return DeMorgan;
// Canonicalize xor to the RHS.
bool SwappedForXor = false;
if (SwappedForXor)
std::swap(Op0, Op1);
- if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1)))
- if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0)))
- if (Value *Res = FoldOrOfICmps(LHS, RHS))
+ {
+ 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)))
// 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))
+ if (Value *Res = FoldOrOfICmps(LHS, RHS, &I))
return CastInst::Create(Op0C->getOpcode(), Res, I.getType());
// If this is or(cast(fcmp), cast(fcmp)), try to fold this even if the
if (Value *V = SimplifyVectorOp(I))
return ReplaceInstUsesWith(I, V);
- if (Value *V = SimplifyXorInst(Op0, Op1, DL))
+ if (Value *V = SimplifyXorInst(Op0, Op1, DL, TLI, DT, AC))
return ReplaceInstUsesWith(I, V);
// (A&B)^(A&C) -> A&(B^C) etc
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)) {
// ~(X & Y) --> (~X | ~Y) - De Morgan's Law
// ~(X | Y) === (~X & ~Y) - De Morgan's Law
- if (isFreeToInvert(Op0I->getOperand(0)) &&
- isFreeToInvert(Op0I->getOperand(1))) {
+ 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 =
}
}
-
- if (ConstantInt *RHS = dyn_cast<ConstantInt>(Op1)) {
- if (RHS->isOne() && Op0->hasOneUse())
+ 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))) {
}
} else if (Op0I->getOpcode() == Instruction::Or) {
// (X|C1)^C2 -> X^(C1|C2) iff X&~C1 == 0
- if (MaskedValueIsZero(Op0I->getOperand(0), Op0CI->getValue())) {
+ 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.
match(Op1I, m_And(m_Specific(A), m_Not(m_Specific(B))))) {
return BinaryOperator::CreateXor(A, B);
}
- // (A ^ B)^(A | B) -> A & B
- if (match(Op0I, m_Xor(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::CreateAnd(A, B);
- }
- // (A | B)^(A ^ B) -> 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(C), m_Value(D)))) {
- if ((A == C && B == D) || (A == D && B == C))
- return BinaryOperator::CreateAnd(A, 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))) &&
return BinaryOperator::CreateOr(A, B);
}
- // (A | B)^(~A) -> (A | ~B)
Value *A = nullptr, *B = nullptr;
- if (match(Op0, m_Or(m_Value(A), m_Value(B))) &&
- match(Op1, m_Not(m_Specific(A))))
- return BinaryOperator::CreateOr(A, Builder->CreateNot(B));
-
// (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))))
projects / oota-llvm.git / blobdiff