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-rw-r--r--lib/Transforms/InstCombine/InstCombineCompares.cpp63
1 files changed, 34 insertions, 29 deletions
diff --git a/lib/Transforms/InstCombine/InstCombineCompares.cpp b/lib/Transforms/InstCombine/InstCombineCompares.cpp
index f48d89b..803b50a 100644
--- a/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -229,10 +229,6 @@ static void ComputeUnsignedMinMaxValuesFromKnownBits(const APInt &KnownZero,
Instruction *InstCombiner::
FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
CmpInst &ICI, ConstantInt *AndCst) {
- // We need TD information to know the pointer size unless this is inbounds.
- if (!GEP->isInBounds() && !DL)
- return nullptr;
-
Constant *Init = GV->getInitializer();
if (!isa<ConstantArray>(Init) && !isa<ConstantDataArray>(Init))
return nullptr;
@@ -303,7 +299,6 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
// the array, this will fully represent all the comparison results.
uint64_t MagicBitvector = 0;
-
// Scan the array and see if one of our patterns matches.
Constant *CompareRHS = cast<Constant>(ICI.getOperand(1));
for (unsigned i = 0, e = ArrayElementCount; i != e; ++i) {
@@ -398,7 +393,7 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
// index down like the GEP would do implicitly. We don't have to do this for
// an inbounds GEP because the index can't be out of range.
if (!GEP->isInBounds()) {
- Type *IntPtrTy = DL->getIntPtrType(GEP->getType());
+ Type *IntPtrTy = DL.getIntPtrType(GEP->getType());
unsigned PtrSize = IntPtrTy->getIntegerBitWidth();
if (Idx->getType()->getPrimitiveSizeInBits() > PtrSize)
Idx = Builder->CreateTrunc(Idx, IntPtrTy);
@@ -487,10 +482,8 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
// - Default to i32
if (ArrayElementCount <= Idx->getType()->getIntegerBitWidth())
Ty = Idx->getType();
- else if (DL)
- Ty = DL->getSmallestLegalIntType(Init->getContext(), ArrayElementCount);
- else if (ArrayElementCount <= 32)
- Ty = Type::getInt32Ty(Init->getContext());
+ else
+ Ty = DL.getSmallestLegalIntType(Init->getContext(), ArrayElementCount);
if (Ty) {
Value *V = Builder->CreateIntCast(Idx, Ty, false);
@@ -514,8 +507,8 @@ FoldCmpLoadFromIndexedGlobal(GetElementPtrInst *GEP, GlobalVariable *GV,
///
/// If we can't emit an optimized form for this expression, this returns null.
///
-static Value *EvaluateGEPOffsetExpression(User *GEP, InstCombiner &IC) {
- const DataLayout &DL = *IC.getDataLayout();
+static Value *EvaluateGEPOffsetExpression(User *GEP, InstCombiner &IC,
+ const DataLayout &DL) {
gep_type_iterator GTI = gep_type_begin(GEP);
// Check to see if this gep only has a single variable index. If so, and if
@@ -628,12 +621,12 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
RHS = RHS->stripPointerCasts();
Value *PtrBase = GEPLHS->getOperand(0);
- if (DL && PtrBase == RHS && GEPLHS->isInBounds()) {
+ if (PtrBase == RHS && GEPLHS->isInBounds()) {
// ((gep Ptr, OFFSET) cmp Ptr) ---> (OFFSET cmp 0).
// This transformation (ignoring the base and scales) is valid because we
// know pointers can't overflow since the gep is inbounds. See if we can
// output an optimized form.
- Value *Offset = EvaluateGEPOffsetExpression(GEPLHS, *this);
+ Value *Offset = EvaluateGEPOffsetExpression(GEPLHS, *this, DL);
// If not, synthesize the offset the hard way.
if (!Offset)
@@ -661,11 +654,11 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
// If we're comparing GEPs with two base pointers that only differ in type
// and both GEPs have only constant indices or just one use, then fold
// the compare with the adjusted indices.
- if (DL && GEPLHS->isInBounds() && GEPRHS->isInBounds() &&
+ if (GEPLHS->isInBounds() && GEPRHS->isInBounds() &&
(GEPLHS->hasAllConstantIndices() || GEPLHS->hasOneUse()) &&
(GEPRHS->hasAllConstantIndices() || GEPRHS->hasOneUse()) &&
PtrBase->stripPointerCasts() ==
- GEPRHS->getOperand(0)->stripPointerCasts()) {
+ GEPRHS->getOperand(0)->stripPointerCasts()) {
Value *LOffset = EmitGEPOffset(GEPLHS);
Value *ROffset = EmitGEPOffset(GEPRHS);
@@ -733,9 +726,7 @@ Instruction *InstCombiner::FoldGEPICmp(GEPOperator *GEPLHS, Value *RHS,
// Only lower this if the icmp is the only user of the GEP or if we expect
// the result to fold to a constant!
- if (DL &&
- GEPsInBounds &&
- (isa<ConstantExpr>(GEPLHS) || GEPLHS->hasOneUse()) &&
+ if (GEPsInBounds && (isa<ConstantExpr>(GEPLHS) || GEPLHS->hasOneUse()) &&
(isa<ConstantExpr>(GEPRHS) || GEPRHS->hasOneUse())) {
// ((gep Ptr, OFFSET1) cmp (gep Ptr, OFFSET2) ---> (OFFSET1 cmp OFFSET2)
Value *L = EmitGEPOffset(GEPLHS);
@@ -1928,8 +1919,8 @@ Instruction *InstCombiner::visitICmpInstWithCastAndCast(ICmpInst &ICI) {
// Turn icmp (ptrtoint x), (ptrtoint/c) into a compare of the input if the
// integer type is the same size as the pointer type.
- if (DL && LHSCI->getOpcode() == Instruction::PtrToInt &&
- DL->getPointerTypeSizeInBits(SrcTy) == DestTy->getIntegerBitWidth()) {
+ if (LHSCI->getOpcode() == Instruction::PtrToInt &&
+ DL.getPointerTypeSizeInBits(SrcTy) == DestTy->getIntegerBitWidth()) {
Value *RHSOp = nullptr;
if (PtrToIntOperator *RHSC = dyn_cast<PtrToIntOperator>(ICI.getOperand(1))) {
Value *RHSCIOp = RHSC->getOperand(0);
@@ -2660,8 +2651,8 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
unsigned BitWidth = 0;
if (Ty->isIntOrIntVectorTy())
BitWidth = Ty->getScalarSizeInBits();
- else if (DL) // Pointers require DL info to get their size.
- BitWidth = DL->getTypeSizeInBits(Ty->getScalarType());
+ else // Get pointer size.
+ BitWidth = DL.getTypeSizeInBits(Ty->getScalarType());
bool isSignBit = false;
@@ -2774,8 +2765,8 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
Op0KnownZero, Op0KnownOne, 0))
return &I;
if (SimplifyDemandedBits(I.getOperandUse(1),
- APInt::getAllOnesValue(BitWidth),
- Op1KnownZero, Op1KnownOne, 0))
+ APInt::getAllOnesValue(BitWidth), Op1KnownZero,
+ Op1KnownOne, 0))
return &I;
// Given the known and unknown bits, compute a range that the LHS could be
@@ -3094,9 +3085,8 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
}
case Instruction::IntToPtr:
// icmp pred inttoptr(X), null -> icmp pred X, 0
- if (RHSC->isNullValue() && DL &&
- DL->getIntPtrType(RHSC->getType()) ==
- LHSI->getOperand(0)->getType())
+ if (RHSC->isNullValue() &&
+ DL.getIntPtrType(RHSC->getType()) == LHSI->getOperand(0)->getType())
return new ICmpInst(I.getPredicate(), LHSI->getOperand(0),
Constant::getNullValue(LHSI->getOperand(0)->getType()));
break;
@@ -3428,7 +3418,7 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
// if A is a power of 2.
if (match(Op0, m_And(m_Value(A), m_Not(m_Value(B)))) &&
match(Op1, m_Zero()) &&
- isKnownToBeAPowerOfTwo(A, false, 0, AC, &I, DT) && I.isEquality())
+ isKnownToBeAPowerOfTwo(A, DL, false, 0, AC, &I, DT) && I.isEquality())
return new ICmpInst(I.getInversePredicate(),
Builder->CreateAnd(A, B),
Op1);
@@ -3563,6 +3553,21 @@ Instruction *InstCombiner::visitICmpInst(ICmpInst &I) {
}
}
+ // (A << C) == (B << C) --> ((A^B) & (~0U >> C)) == 0
+ if (match(Op0, m_OneUse(m_Shl(m_Value(A), m_ConstantInt(Cst1)))) &&
+ match(Op1, m_OneUse(m_Shl(m_Value(B), m_Specific(Cst1))))) {
+ unsigned TypeBits = Cst1->getBitWidth();
+ unsigned ShAmt = (unsigned)Cst1->getLimitedValue(TypeBits);
+ if (ShAmt < TypeBits && ShAmt != 0) {
+ Value *Xor = Builder->CreateXor(A, B, I.getName() + ".unshifted");
+ APInt AndVal = APInt::getLowBitsSet(TypeBits, TypeBits - ShAmt);
+ Value *And = Builder->CreateAnd(Xor, Builder->getInt(AndVal),
+ I.getName() + ".mask");
+ return new ICmpInst(I.getPredicate(), And,
+ Constant::getNullValue(Cst1->getType()));
+ }
+ }
+
// Transform "icmp eq (trunc (lshr(X, cst1)), cst" to
// "icmp (and X, mask), cst"
uint64_t ShAmt = 0;
generated by cgit v1.1 at 2024-12-22 11:26:49 +0000