//
//===----------------------------------------------------------------------===//
-#include "InstCombine.h"
-#include "llvm/Intrinsics.h"
+#include "InstCombineInternal.h"
#include "llvm/Analysis/InstructionSimplify.h"
-#include "llvm/Support/ConstantRange.h"
-#include "llvm/Support/PatternMatch.h"
+#include "llvm/IR/ConstantRange.h"
+#include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/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));
-}
-/// SubOne - Subtract one from a ConstantInt.
-static Constant *SubOne(ConstantInt *C) {
- return ConstantInt::get(C->getContext(), C->getValue()-1);
-}
-
-/// 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;
-}
+#define DEBUG_TYPE "instcombine"
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;
}
-
+
// Constants can be considered to be not'ed values...
if (ConstantInt *C = dyn_cast<ConstantInt>(V))
return ConstantInt::get(C->getType(), ~C->getValue());
- return 0;
+ return nullptr;
}
-
-/// getICmpCode - Encode a icmp predicate into a three bit mask. These bits
-/// are carefully arranged to allow folding of expressions such as:
-///
-/// (A < B) | (A > B) --> (A != B)
-///
-/// Note that this is only valid if the first and second predicates have the
-/// same sign. Is illegal to do: (A u< B) | (A s> B)
-///
-/// Three bits are used to represent the condition, as follows:
-/// 0 A > B
-/// 1 A == B
-/// 2 A < B
-///
-/// <=> Value Definition
-/// 000 0 Always false
-/// 001 1 A > B
-/// 010 2 A == B
-/// 011 3 A >= B
-/// 100 4 A < B
-/// 101 5 A != B
-/// 110 6 A <= B
-/// 111 7 Always true
-///
-static unsigned getICmpCode(const ICmpInst *ICI) {
- switch (ICI->getPredicate()) {
- // False -> 0
- case ICmpInst::ICMP_UGT: return 1; // 001
- case ICmpInst::ICMP_SGT: return 1; // 001
- case ICmpInst::ICMP_EQ: return 2; // 010
- case ICmpInst::ICMP_UGE: return 3; // 011
- case ICmpInst::ICMP_SGE: return 3; // 011
- case ICmpInst::ICMP_ULT: return 4; // 100
- case ICmpInst::ICMP_SLT: return 4; // 100
- case ICmpInst::ICMP_NE: return 5; // 101
- case ICmpInst::ICMP_ULE: return 6; // 110
- case ICmpInst::ICMP_SLE: return 6; // 110
- // True -> 7
- default:
- llvm_unreachable("Invalid ICmp predicate!");
- return 0;
- }
-}
-
-/// 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) {
default:
// Not expecting FCMP_FALSE and FCMP_TRUE;
llvm_unreachable("Unexpected FCmp predicate!");
- return 0;
}
}
-/// getICmpValue - 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 *getICmpValue(bool Sign, unsigned Code, Value *LHS, Value *RHS,
- InstCombiner::BuilderTy *Builder) {
- CmpInst::Predicate Pred;
- switch (Code) {
- default: assert(0 && "Illegal ICmp code!");
- case 0: // False.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
- case 1: Pred = Sign ? ICmpInst::ICMP_SGT : ICmpInst::ICMP_UGT; break;
- case 2: Pred = ICmpInst::ICMP_EQ; break;
- case 3: Pred = Sign ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE; break;
- case 4: Pred = Sign ? ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT; break;
- case 5: Pred = ICmpInst::ICMP_NE; break;
- case 6: Pred = Sign ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_ULE; break;
- case 7: // True.
- return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
- }
- return Builder->CreateICmp(Pred, LHS, RHS);
+/// 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;
+ if (Value *NewConstant = getICmpValue(Sign, Code, LHS, RHS, NewPred))
+ return NewConstant;
+ 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) {
CmpInst::Predicate Pred;
switch (code) {
- default: assert(0 && "Illegal FCmp code!");
+ default: llvm_unreachable("Illegal FCmp code!");
case 0: Pred = isordered ? FCmpInst::FCMP_ORD : FCmpInst::FCMP_UNO; break;
case 1: Pred = isordered ? FCmpInst::FCMP_OGT : FCmpInst::FCMP_UGT; break;
case 2: Pred = isordered ? FCmpInst::FCMP_OEQ : FCmpInst::FCMP_UEQ; break;
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:
- if (!isordered) return ConstantInt::getTrue(LHS->getContext());
+ case 7:
+ if (!isordered)
+ return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 1);
Pred = FCmpInst::FCMP_ORD; break;
}
return Builder->CreateFCmp(Pred, LHS, RHS);
}
-/// PredicatesFoldable - Return true if both predicates match sign or if at
-/// least one of them is an equality comparison (which is signless).
-static bool PredicatesFoldable(ICmpInst::Predicate p1, ICmpInst::Predicate p2) {
- return (CmpInst::isSigned(p1) == CmpInst::isSigned(p2)) ||
- (CmpInst::isSigned(p1) && ICmpInst::isEquality(p2)) ||
- (CmpInst::isSigned(p2) && ICmpInst::isEquality(p1));
+/// \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);
}
-// 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.
+/// 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,
BinaryOperator &TheAnd) {
Value *X = Op->getOperand(0);
- Constant *Together = 0;
+ Constant *Together = nullptr;
if (!Op->isShift())
Together = ConstantExpr::getAnd(AndRHS, OpRHS);
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
return BinaryOperator::CreateOr(And, OpRHS);
}
}
-
+
break;
case Instruction::Add:
if (Op->hasOneUse()) {
// Adding a one to a single bit bit-field should be turned into an XOR
// of the bit. First thing to check is to see if this AND is with a
// single bit constant.
- const APInt &AndRHSV = cast<ConstantInt>(AndRHS)->getValue();
+ const APInt &AndRHSV = AndRHS->getValue();
// If there is only one bit set.
if (AndRHSV.isPowerOf2()) {
// Ok, at this point, we know that we are masking the result of the
// ADD down to exactly one bit. If the constant we are adding has
// no bits set below this bit, then we can eliminate the ADD.
- const APInt& AddRHS = cast<ConstantInt>(OpRHS)->getValue();
+ const APInt& AddRHS = OpRHS->getValue();
// Check to see if any bits below the one bit set in AndRHSV are set.
if ((AddRHS & (AndRHSV-1)) == 0) {
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShlMask(APInt::getHighBitsSet(BitWidth, BitWidth-OpRHSVal));
- ConstantInt *CI = ConstantInt::get(AndRHS->getContext(),
- AndRHS->getValue() & ShlMask);
+ ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShlMask);
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;
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
- ConstantInt *CI = ConstantInt::get(Op->getContext(),
- AndRHS->getValue() & ShrMask);
+ ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShrMask);
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;
uint32_t BitWidth = AndRHS->getType()->getBitWidth();
uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
- Constant *C = ConstantInt::get(Op->getContext(),
- AndRHS->getValue() & ShrMask);
+ Constant *C = Builder->getInt(AndRHS->getValue() & ShrMask);
if (C == AndRHS) { // Masking out bits shifted in.
// (Val ashr C1) & C2 -> (Val lshr C1) & C2
// Make the argument unsigned.
}
break;
}
- return 0;
+ return nullptr;
}
-
-/// 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
+/// 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
/// 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());
+ return Builder->getFalse();
// 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);
}
}
if (Lo == Hi) // Trivially true.
- return ConstantInt::getTrue(V->getContext());
+ return Builder->getTrue();
// 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);
}
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();
// 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:
-///
+/// 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
Instruction &I) {
Instruction *LHSI = dyn_cast<Instruction>(LHS);
if (!LHSI || LHSI->getNumOperands() != 2 ||
- !isa<ConstantInt>(LHSI->getOperand(1))) return 0;
+ !isa<ConstantInt>(LHSI->getOperand(1))) return nullptr;
ConstantInt *N = cast<ConstantInt>(LHSI->getOperand(1));
switch (LHSI->getOpcode()) {
- default: return 0;
+ default: return nullptr;
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;
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;
}
}
- return 0;
+ return nullptr;
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;
+ return nullptr;
}
-
+
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
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,
+/// 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 != 0 && !ACst->isZero() &&
+ bool icmp_abit = (ACst && !ACst->isZero() &&
ACst->getValue().isPowerOf2());
- bool icmp_bbit = (BCst != 0 && !BCst->isZero() &&
+ bool icmp_bbit = (BCst && !BCst->isZero() &&
BCst->getValue().isPowerOf2());
unsigned result = 0;
- if (CCst != 0 && CCst->isZero()) {
+ if (CCst && CCst->isZero()) {
// if C is zero, then both A and B qualify as mask
result |= (icmp_eq ? (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_Mask_AllZeroes |
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;
FoldMskICmp_AMask_NotMixed)
: (FoldMskICmp_Mask_AllZeroes |
FoldMskICmp_AMask_Mixed));
- }
- else if (ACst != 0 && CCst != 0 &&
- ConstantExpr::getAnd(ACst, CCst) == CCst) {
+ } else if (ACst && CCst &&
+ 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 && CCst &&
+ ConstantExpr::getAnd(BCst, CCst) == CCst) {
result |= (icmp_eq ? FoldMskICmp_BMask_Mixed
: FoldMskICmp_BMask_NotMixed);
}
return result;
}
-/// foldLogOpOfMaskedICmpsHelper:
-/// 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,
+/// 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;
+}
+
+/// 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) {
+ ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1));
+ if (!C)
+ return false;
+
+ switch (I->getPredicate()) {
+ default:
+ return false;
+ case ICmpInst::ICMP_SLT:
+ // X < 0 is equivalent to (X & SignBit) != 0.
+ if (!C->isZero())
+ return false;
+ Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
+ Pred = ICmpInst::ICMP_NE;
+ break;
+ case ICmpInst::ICMP_SGT:
+ // X > -1 is equivalent to (X & SignBit) == 0.
+ if (!C->isAllOnesValue())
+ return false;
+ Y = ConstantInt::get(I->getContext(), APInt::getSignBit(C->getBitWidth()));
+ Pred = ICmpInst::ICMP_EQ;
+ break;
+ case ICmpInst::ICMP_ULT:
+ // X <u 2^n is equivalent to (X & ~(2^n-1)) == 0.
+ if (!C->getValue().isPowerOf2())
+ return false;
+ Y = ConstantInt::get(I->getContext(), -C->getValue());
+ Pred = ICmpInst::ICMP_EQ;
+ break;
+ case ICmpInst::ICMP_UGT:
+ // X >u 2^n-1 is equivalent to (X & ~(2^n-1)) != 0.
+ if (!(C->getValue() + 1).isPowerOf2())
+ return false;
+ Y = ConstantInt::get(I->getContext(), ~C->getValue());
+ Pred = ICmpInst::ICMP_NE;
+ break;
+ }
+
+ X = I->getOperand(0);
+ Z = ConstantInt::getNullValue(C->getType());
+ return true;
+}
+
+/// 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 = LHS->getPredicate(), RHSCC = RHS->getPredicate();
- if (LHSCC != ICmpInst::ICMP_EQ && LHSCC != ICmpInst::ICMP_NE) return 0;
- if (RHSCC != ICmpInst::ICMP_EQ && RHSCC != ICmpInst::ICMP_NE) return 0;
+ 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,
+ // 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);
Value *L11,*L12,*L21,*L22;
- if (match(L1, m_And(m_Value(L11), m_Value(L12)))) {
- if (!match(L2, m_And(m_Value(L21), m_Value(L22))))
- L21 = L22 = 0;
- }
- else {
- if (!match(L2, m_And(m_Value(L11), m_Value(L12))))
- return 0;
- std::swap(L1, L2);
- L21 = L22 = 0;
+ // 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 (match(R1, m_And(m_Value(R11), m_Value(R12)))) {
- if (R11 != 0 && (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22)) {
- A = R11; D = R12; E = R2; ok = true;
+ 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());
}
- else
- if (R12 != 0 && (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22)) {
+
+ 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;
}
}
- if (!ok && match(R2, m_And(m_Value(R11), m_Value(R12)))) {
- if (R11 != 0 && (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22)) {
- A = R11; D = R12; E = R1; 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 in 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());
}
- else
- if (R12 != 0 && (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22)) {
+
+ 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
+ } else {
return 0;
+ }
}
if (!ok)
return 0;
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;
}
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,
- ICmpInst::Predicate NEWCC,
- llvm::InstCombiner::BuilderTy* Builder) {
- Value *A = 0, *B = 0, *C = 0, *D = 0, *E = 0;
- unsigned mask = foldLogOpOfMaskedICmpsHelper(A, B, C, D, E, LHS, RHS);
- if (mask == 0) return 0;
-
- if (NEWCC == ICmpInst::ICMP_NE)
- mask >>= 1; // treat "Not"-states as normal states
+
+/// 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), 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)
+ // (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);
}
- 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);
+ 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);
+ 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)
+
+ // 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.
- ConstantInt *BCst = dyn_cast<ConstantInt>(B);
- if (BCst == 0) return 0;
- 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);
- if (CCst == 0) return 0;
- if (LHS->getPredicate() != NEWCC)
- CCst = dyn_cast<ConstantInt>( ConstantExpr::getXor(BCst, CCst) );
+ if (!CCst) return nullptr;
ConstantInt *ECst = dyn_cast<ConstantInt>(E);
- if (ECst == 0) return 0;
- if (RHS->getPredicate() != NEWCC)
- ECst = dyn_cast<ConstantInt>( ConstantExpr::getXor(DCst, ECst) );
- ConstantInt* MCst = dyn_cast<ConstantInt>(
- ConstantExpr::getAnd(ConstantExpr::getAnd(BCst, DCst),
- ConstantExpr::getXor(CCst, ECst)) );
+ 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 (!MCst->isZero())
- return 0;
+ 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 0;
+ 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();
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) & getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
- return getICmpValue(isSigned, Code, Op0, Op1, Builder);
+ 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, ICmpInst::ICMP_EQ, Builder))
+ 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 == 0 || RHSCst == 0) return 0;
-
+ 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
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);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
-
- // (icmp slt A, 0) & (icmp slt B, 0) --> (icmp slt (A&B), 0)
- if (LHSCC == ICmpInst::ICMP_SLT && LHSCst->isZero()) {
- Value *NewAnd = Builder->CreateAnd(Val, Val2);
- return Builder->CreateICmp(LHSCC, NewAnd, LHSCst);
- }
-
- // (icmp sgt A, -1) & (icmp sgt B, -1) --> (icmp sgt (A|B), -1)
- if (LHSCC == ICmpInst::ICMP_SGT && LHSCst->isAllOnesValue()) {
- 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 CA are zero.
- if (LHSCC == RHSCC && ICmpInst::isEquality(LHSCC) &&
+ // 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 = 0, *BigCst = 0;
+ 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;
- }
- // (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;
}
// Check that the low bits are zero.
APInt Low = APInt::getLowBitsSet(BigBitSize, SmallBitSize);
- if ((Low & AndCst->getValue()) == 0) {
+ 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);
}
}
}
-
+
// From here on, we only handle:
// (icmp1 A, C1) & (icmp2 A, C2) --> something simpler.
- if (Val != Val2) return 0;
-
+ 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 0;
+ return nullptr;
// 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 RHSRange =
- ConstantRange::makeICmpRegion(RHSCC, RHSCst->getValue());
+ ConstantRange LHSRange =
+ ConstantRange::makeAllowedICmpRegion(LHSCC, LHSCst->getValue());
+ ConstantRange RHSRange =
+ ConstantRange::makeAllowedICmpRegion(RHSCC, RHSCst->getValue());
if (LHSRange.intersectWith(RHSRange).isEmptySet())
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
// We can't fold (ugt x, C) & (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
- return 0;
-
+ return nullptr;
+
// 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);
// 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?");
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
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));
+ return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
+ Val->getName()+".cmp");
}
break; // (X != 13 & X != 15) -> no change
}
}
break;
}
-
- return 0;
+
+ 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) {
+ 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 ConstantInt::getFalse(LHS->getContext());
+ 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 0;
+ return nullptr;
}
-
+
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)
return RHS;
if (Op1CC == FCmpInst::FCMP_TRUE)
return LHS;
-
+
bool Op0Ordered;
bool Op1Ordered;
unsigned Op0Pred = getFCmpCode(Op0CC, Op0Ordered);
unsigned Op1Pred = getFCmpCode(Op1CC, Op1Ordered);
+ // uno && ord -> false
+ if (Op0Pred == 0 && Op1Pred == 0 && Op0Ordered != Op1Ordered)
+ return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
if (Op1Pred == 0) {
std::swap(LHS, RHS);
std::swap(Op0Pred, Op1Pred);
std::swap(Op0Ordered, Op1Ordered);
}
if (Op0Pred == 0) {
- // uno && ueq -> uno && (uno || eq) -> ueq
+ // uno && ueq -> uno && (uno || eq) -> uno
// ord && olt -> ord && (ord && lt) -> olt
- if (Op0Ordered == Op1Ordered)
+ if (!Op0Ordered && (Op0Ordered == Op1Ordered))
+ return LHS;
+ if (Op0Ordered && (Op0Ordered == Op1Ordered))
return RHS;
-
+
// uno && oeq -> uno && (ord && eq) -> false
- // uno && ord -> false
if (!Op0Ordered)
return ConstantInt::get(CmpInst::makeCmpResultType(LHS->getType()), 0);
// ord && ueq -> ord && (uno || eq) -> oeq
}
}
- return 0;
+ 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 = SimplifyAndInst(Op0, Op1, TD))
+ 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
+ // 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 (Value *V = SimplifyBSwap(I))
+ return ReplaceInstUsesWith(I, V);
if (ConstantInt *AndRHS = dyn_cast<ConstantInt>(Op1)) {
const APInt &AndRHSMask = AndRHS->getValue();
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)) {
+ 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);
}
}
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 = 0; ConstantInt *YC = 0;
+ 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
+ // 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());
return NV;
}
+ if (Instruction *DeMorgan = matchDeMorgansLaws(I, Builder))
+ return DeMorgan;
- // (~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);
- }
-
{
- Value *A = 0, *B = 0, *C = 0, *D = 0;
+ 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);
-
- if (Op0->hasOneUse() &&
- match(Op0, m_Xor(m_Value(A), m_Value(B)))) {
- if (A == Op1) { // (A^B)&A -> A&(A^B)
- I.swapOperands(); // Simplify below
- std::swap(Op0, Op1);
- } else if (B == Op1) { // (A^B)&B -> B&(B^A)
- cast<BinaryOperator>(Op0)->swapOperands();
- I.swapOperands(); // Simplify below
- std::swap(Op0, Op1);
+
+ // A&(A^B) => A & ~B
+ {
+ Value *tmpOp0 = Op0;
+ Value *tmpOp1 = Op1;
+ if (Op0->hasOneUse() &&
+ match(Op0, m_Xor(m_Value(A), m_Value(B)))) {
+ if (A == Op1 || B == Op1 ) {
+ tmpOp1 = Op0;
+ tmpOp0 = Op1;
+ // Simplify below
+ }
}
- }
- if (Op1->hasOneUse() &&
- match(Op1, m_Xor(m_Value(A), m_Value(B)))) {
- if (B == Op0) { // B&(A^B) -> B&(B^A)
- cast<BinaryOperator>(Op1)->swapOperands();
- std::swap(A, B);
+ if (tmpOp1->hasOneUse() &&
+ match(tmpOp1, m_Xor(m_Value(A), m_Value(B)))) {
+ if (B == tmpOp0) {
+ std::swap(A, B);
+ }
+ // Notice that the patten (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));
}
- // Notice that the patten (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 == Op0 && !isa<Constant>(A)) // A&(A^B) -> A & ~B
- return BinaryOperator::CreateAnd(A, Builder->CreateNot(B, "tmp"));
}
// (A&((~A)|B)) -> A&B
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);
}
-
- if (ICmpInst *RHS = dyn_cast<ICmpInst>(Op1))
- if (ICmpInst *LHS = dyn_cast<ICmpInst>(Op0))
+
+ {
+ 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);
-
-
+
+
// fold (and (cast A), (cast B)) -> (cast (and A, B))
if (CastInst *Op0C = dyn_cast<CastInst>(Op0))
if (CastInst *Op1C = dyn_cast<CastInst>(Op1)) {
- const Type *SrcTy = Op0C->getOperand(0)->getType();
+ Type *SrcTy = Op0C->getOperand(0)->getType();
if (Op0C->getOpcode() == Op1C->getOpcode() && // same cast kind ?
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))
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() &&
- 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,
- SI1->getOperand(1));
- }
+
+ {
+ Value *X = nullptr;
+ 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;
+ 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
/// always in the local (OverallLeftShift) coordinate space.
///
static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask,
- SmallVector<Value*, 8> &ByteValues) {
+ SmallVectorImpl<Value *> &ByteValues) {
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If this is an or instruction, it may be an inner node of the bswap.
if (I->getOpcode() == Instruction::Or) {
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()))
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);
}
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;
// 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
// into a byteswap. At least one of the two bytes would not be aligned with
// their ultimate destination.
if (!isPowerOf2_32(ByteMask)) return true;
- unsigned InputByteNo = CountTrailingZeros_32(ByteMask);
-
+ unsigned InputByteNo = countTrailingZeros(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
// part of the value (e.g. byte 3) then it must be shifted right. If from the
// low part, it must be shifted left.
unsigned DestByteNo = InputByteNo + OverallLeftShift;
- if (InputByteNo < ByteValues.size()/2) {
- if (ByteValues.size()-1-DestByteNo != InputByteNo)
- return true;
- } else {
- if (ByteValues.size()-1-DestByteNo != InputByteNo)
- return true;
- }
-
+ 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)
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) {
- const IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
- if (!ITy || ITy->getBitWidth() % 16 ||
+ IntegerType *ITy = dyn_cast<IntegerType>(I.getType());
+ if (!ITy || ITy->getBitWidth() % 16 ||
// ByteMask only allows up to 32-byte values.
- ITy->getBitWidth() > 32*8)
- return 0; // Can only bswap pairs of bytes. Can't do vectors.
-
+ ITy->getBitWidth() > 32*8)
+ return nullptr; // 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;
-
+ return nullptr;
+
// 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.
-
+ if (!V) return nullptr; // 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)
- return 0;
- const Type *Tys[] = { ITy };
+ return nullptr;
Module *M = I.getParent()->getParent()->getParent();
- Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, Tys, 1);
+ Function *F = Intrinsic::getDeclaration(M, Intrinsic::bswap, ITy);
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.
- Value *Cond = 0;
+ Value *Cond = nullptr;
if (!match(A, m_SExt(m_Value(Cond))) ||
!Cond->getType()->isIntegerTy(1))
- return 0;
+ return nullptr;
// ((cond?-1:0)&C) | (B&(cond?0:-1)) -> cond ? C : B.
if (match(D, m_Not(m_SExt(m_Specific(Cond)))))
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);
if (match(B, m_SExt(m_Not(m_Specific(Cond)))))
return SelectInst::Create(Cond, C, D);
- return 0;
+ 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)
+ // 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) &&
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) | getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
- return getICmpValue(isSigned, Code, Op0, Op1, Builder);
+ 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, ICmpInst::ICMP_NE, Builder))
+ if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, 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 (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)
Value *NewOr = Builder->CreateOr(Val, Val2);
return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
}
-
- // (icmp slt A, 0) | (icmp slt B, 0) --> (icmp slt (A|B), 0)
- if (LHSCC == ICmpInst::ICMP_SLT && LHSCst->isZero()) {
- Value *NewOr = Builder->CreateOr(Val, Val2);
- return Builder->CreateICmp(LHSCC, NewOr, LHSCst);
- }
-
- // (icmp sgt A, -1) | (icmp sgt B, -1) --> (icmp sgt (A&B), -1)
- if (LHSCC == ICmpInst::ICMP_SGT && LHSCst->isAllOnesValue()) {
- Value *NewAnd = Builder->CreateAnd(Val, Val2);
- return Builder->CreateICmp(LHSCC, NewAnd, LHSCst);
- }
}
// (icmp ult (X + CA), C1) | (icmp eq X, C2) -> (icmp ule (X + CA), C1)
// From here on, we only handle:
// (icmp1 A, C1) | (icmp2 A, C2) --> something simpler.
- if (Val != Val2) return 0;
-
+ 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 0;
-
+ return nullptr;
+
// We can't fold (ugt x, C) | (sgt x, C2).
if (!PredicatesFoldable(LHSCC, RHSCC))
- return 0;
-
+ return nullptr;
+
// 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
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)) == 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);
+ }
+ }
+
if (LHSCst == SubOne(RHSCst)) {
// (X == 13 | X == 14) -> X-13 <u 2
Constant *AddCST = ConstantExpr::getNeg(LHSCst);
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
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 ConstantInt::getTrue(LHS->getContext());
+ return Builder->getTrue();
}
- break;
case ICmpInst::ICMP_ULT:
switch (RHSCC) {
default: llvm_unreachable("Unknown integer condition code!");
break;
case ICmpInst::ICMP_NE: // (X u> 13 | X != 15) -> true
case ICmpInst::ICMP_ULT: // (X u> 13 | X u< 15) -> true
- return ConstantInt::getTrue(LHS->getContext());
+ return Builder->getTrue();
case ICmpInst::ICMP_SLT: // (X u> 13 | X s< 15) -> no change
break;
}
break;
case ICmpInst::ICMP_NE: // (X s> 13 | X != 15) -> true
case ICmpInst::ICMP_SLT: // (X s> 13 | X s< 15) -> true
- return ConstantInt::getTrue(LHS->getContext());
+ return Builder->getTrue();
case ICmpInst::ICMP_ULT: // (X s> 13 | X u< 15) -> no change
break;
}
break;
}
- return 0;
+ 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 &&
+ 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 ConstantInt::getTrue(LHS->getContext());
-
+ 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 0;
+
+ return nullptr;
}
-
+
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);
return getFCmpValue(Op0Ordered, Op0Pred|Op1Pred, Op0LHS, Op0RHS, Builder);
}
}
- return 0;
+ return nullptr;
}
-/// FoldOrWithConstants - This helper function folds:
+/// 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 0;
+ if (!CI1) return nullptr;
- Value *V1 = 0;
- ConstantInt *CI2 = 0;
- if (!match(Op, m_And(m_Value(V1), m_ConstantInt(CI2)))) return 0;
+ 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 0;
+ 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 0;
+ 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 = SimplifyOrInst(Op0, Op1, TD))
+ 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
+ // 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 = 0; Value *X = 0;
+ 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))) &&
Op0->hasOneUse()) {
Value *Or = Builder->CreateOr(X, RHS);
Or->takeName(Op0);
- return BinaryOperator::CreateAnd(Or,
- ConstantInt::get(I.getContext(),
- RHS->getValue() | C1->getValue()));
+ return BinaryOperator::CreateAnd(Or,
+ Builder->getInt(RHS->getValue() | C1->getValue()));
}
// (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
Value *Or = Builder->CreateOr(X, RHS);
Or->takeName(Op0);
return BinaryOperator::CreateXor(Or,
- ConstantInt::get(I.getContext(),
- C1->getValue() & ~RHS->getValue()));
+ Builder->getInt(C1->getValue() & ~RHS->getValue()));
}
// Try to fold constant and into select arguments.
return NV;
}
- Value *A = 0, *B = 0;
- ConstantInt *C1 = 0, *C2 = 0;
+ Value *A = nullptr, *B = nullptr;
+ ConstantInt *C1 = nullptr, *C2 = nullptr;
// (A | B) | C and A | (B | C) -> bswap if possible.
// (A >> B) | (C << D) and (A << B) | (B >> C) -> bswap if possible.
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))) &&
- 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);
}
+ // ((~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 = 0, *D = 0;
+ 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 = 0, *V2 = 0;
+ Value *V1 = nullptr, *V2 = nullptr;
C1 = dyn_cast<ConstantInt>(C);
C2 = dyn_cast<ConstantInt>(D);
if (C1 && C2) { // (A & C1)|(B & C2)
- // If we have: ((V + N) & C1) | (V & C2)
- // .. and C2 = ~C1 and C2 is 0+1+ and (N & C2) == 0
- // replace with V+N.
- if (C1->getValue() == ~C2->getValue()) {
- if ((C2->getValue() & (C2->getValue()+1)) == 0 && // C2 == 0+1+
- match(A, m_Add(m_Value(V1), m_Value(V2)))) {
- // Add commutes, try both ways.
- if (V1 == B && MaskedValueIsZero(V2, C2->getValue()))
- return ReplaceInstUsesWith(I, A);
- if (V2 == B && MaskedValueIsZero(V1, C2->getValue()))
- return ReplaceInstUsesWith(I, A);
- }
- // Or commutes, try both ways.
- if ((C1->getValue() & (C1->getValue()+1)) == 0 &&
- match(B, m_Add(m_Value(V1), m_Value(V2)))) {
- // Add commutes, try both ways.
- if (V1 == A && MaskedValueIsZero(V2, C1->getValue()))
- return ReplaceInstUsesWith(I, B);
- if (V2 == A && MaskedValueIsZero(V1, C1->getValue()))
- 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
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,
- ConstantInt::get(A->getContext(),
- C1->getValue()|C2->getValue()));
+ 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,
- ConstantInt::get(B->getContext(),
- C1->getValue()|C2->getValue()));
-
+ 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 = 0, *C4 = 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,
- ConstantInt::get(B->getContext(),
- C1->getValue()|C2->getValue()));
+ Builder->getInt(C1->getValue()|C2->getValue()));
}
}
}
Instruction *Ret = FoldOrWithConstants(I, Op0, A, V1, D);
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() &&
- 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,
- SI1->getOperand(1));
- }
+ // ((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) == (~(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);
- }
+ // (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.
- if (match(Op0, m_Xor(m_Value(), m_Value())))
+ 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);
return BinaryOperator::CreateOr(Not, Op0);
}
- if (ICmpInst *RHS = dyn_cast<ICmpInst>(I.getOperand(1)))
- if (ICmpInst *LHS = dyn_cast<ICmpInst>(I.getOperand(0)))
- if (Value *Res = FoldOrOfICmps(LHS, RHS))
+ // (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);
-
+
// fold (or (cast A), (cast B)) -> (cast (or A, B))
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
CastInst *Op1C = dyn_cast<CastInst>(Op1);
if (Op1C && Op0C->getOpcode() == Op1C->getOpcode()) {// same cast kind ?
- const Type *SrcTy = Op0C->getOperand(0)->getType();
+ Type *SrcTy = Op0C->getOperand(0)->getType();
if (SrcTy == Op1C->getOperand(0)->getType() &&
SrcTy->isIntOrIntVectorTy()) {
Value *Op0COp = Op0C->getOperand(0), *Op1COp = Op1C->getOperand(0);
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))
+ 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
// cast is otherwise not optimizable. This happens for vector sexts.
if (FCmpInst *RHS = dyn_cast<FCmpInst>(Op1COp))
Inner->takeName(Op0);
return BinaryOperator::CreateOr(Inner, C1);
}
-
- return Changed ? &I : 0;
+
+ // 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 = SimplifyXorInst(Op0, Op1, TD))
+ 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
+ // 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 ||
+ 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
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)) &&
- 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))) {
if (CI->hasOneUse() && Op0C->hasOneUse()) {
Instruction::CastOps Opcode = Op0C->getOpcode();
if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
- (RHS == ConstantExpr::getCast(Opcode,
- ConstantInt::getTrue(I.getContext()),
+ (RHS == ConstantExpr::getCast(Opcode, Builder->getTrue(),
Op0C->getDestTy()))) {
CI->setPredicate(CI->getInversePredicate());
return CastInst::Create(Opcode, CI, Op0C->getType());
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
Op0I->getOperand(0));
} else if (RHS->getValue().isSignBit()) {
// (X + C) ^ signbit -> (X + C + signbit)
- Constant *C = ConstantInt::get(I.getContext(),
- RHS->getValue() + Op0CI->getValue());
+ 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())) {
+ 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,
+ 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);
+ }
}
}
}
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();
}
}
}
-
+
BinaryOperator *Op0I = dyn_cast<BinaryOperator>(Op0);
if (Op0I) {
Value *A, *B;
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, "tmp"));
- } else if (match(Op0I, m_And(m_Value(A), m_Value(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, "tmp"), Op1);
+ return BinaryOperator::CreateAnd(Builder->CreateNot(A), Op1);
}
}
}
-
- // (X >> Z) ^ (Y >> Z) -> (X^Y) >> Z for all shifts.
- if (Op0I && Op1I && Op0I->isShift() &&
- Op0I->getOpcode() == Op1I->getOpcode() &&
- Op0I->getOperand(1) == Op1I->getOperand(1) &&
- (Op1I->hasOneUse() || Op1I->hasOneUse())) {
- Value *NewOp =
- Builder->CreateXor(Op0I->getOperand(0), Op1I->getOperand(0),
- Op0I->getName());
- 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);
}
+ // (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)))
Value *Op0 = LHS->getOperand(0), *Op1 = LHS->getOperand(1);
unsigned Code = getICmpCode(LHS) ^ getICmpCode(RHS);
bool isSigned = LHS->isSigned() || RHS->isSigned();
- return ReplaceInstUsesWith(I,
- getICmpValue(isSigned, Code, Op0, Op1, Builder));
+ return ReplaceInstUsesWith(I,
+ getNewICmpValue(isSigned, Code, Op0, Op1,
+ Builder));
}
}
if (CastInst *Op0C = dyn_cast<CastInst>(Op0)) {
if (CastInst *Op1C = dyn_cast<CastInst>(Op1))
if (Op0C->getOpcode() == Op1C->getOpcode()) { // same cast kind?
- const Type *SrcTy = Op0C->getOperand(0)->getType();
+ 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());
}
}
- return Changed ? &I : 0;
+ return Changed ? &I : nullptr;
}
projects / oota-llvm.git / blobdiff