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-rw-r--r--contrib/llvm/lib/Analysis/InstructionSimplify.cpp46
1 files changed, 35 insertions, 11 deletions
diff --git a/contrib/llvm/lib/Analysis/InstructionSimplify.cpp b/contrib/llvm/lib/Analysis/InstructionSimplify.cpp
index bf77451..b867af1 100644
--- a/contrib/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/contrib/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -668,7 +668,8 @@ Value *llvm::SimplifyAddInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW,
/// follow non-inbounds geps. This allows it to remain usable for icmp ult/etc.
/// folding.
static Constant *stripAndComputeConstantOffsets(const DataLayout *TD,
- Value *&V) {
+ Value *&V,
+ bool AllowNonInbounds = false) {
assert(V->getType()->getScalarType()->isPointerTy());
// Without DataLayout, just be conservative for now. Theoretically, more could
@@ -676,8 +677,8 @@ static Constant *stripAndComputeConstantOffsets(const DataLayout *TD,
if (!TD)
return ConstantInt::get(IntegerType::get(V->getContext(), 64), 0);
- unsigned IntPtrWidth = TD->getPointerSizeInBits();
- APInt Offset = APInt::getNullValue(IntPtrWidth);
+ Type *IntPtrTy = TD->getIntPtrType(V->getType())->getScalarType();
+ APInt Offset = APInt::getNullValue(IntPtrTy->getIntegerBitWidth());
// Even though we don't look through PHI nodes, we could be called on an
// instruction in an unreachable block, which may be on a cycle.
@@ -685,7 +686,8 @@ static Constant *stripAndComputeConstantOffsets(const DataLayout *TD,
Visited.insert(V);
do {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
- if (!GEP->isInBounds() || !GEP->accumulateConstantOffset(*TD, Offset))
+ if ((!AllowNonInbounds && !GEP->isInBounds()) ||
+ !GEP->accumulateConstantOffset(*TD, Offset))
break;
V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast) {
@@ -701,7 +703,6 @@ static Constant *stripAndComputeConstantOffsets(const DataLayout *TD,
"Unexpected operand type!");
} while (Visited.insert(V));
- Type *IntPtrTy = TD->getIntPtrType(V->getContext());
Constant *OffsetIntPtr = ConstantInt::get(IntPtrTy, Offset);
if (V->getType()->isVectorTy())
return ConstantVector::getSplat(V->getType()->getVectorNumElements(),
@@ -1363,6 +1364,10 @@ static Value *SimplifyLShrInst(Value *Op0, Value *Op1, bool isExact,
if (Value *V = SimplifyShift(Instruction::LShr, Op0, Op1, Q, MaxRecurse))
return V;
+ // X >> X -> 0
+ if (Op0 == Op1)
+ return Constant::getNullValue(Op0->getType());
+
// undef >>l X -> 0
if (match(Op0, m_Undef()))
return Constant::getNullValue(Op0->getType());
@@ -1391,6 +1396,10 @@ static Value *SimplifyAShrInst(Value *Op0, Value *Op1, bool isExact,
if (Value *V = SimplifyShift(Instruction::AShr, Op0, Op1, Q, MaxRecurse))
return V;
+ // X >> X -> 0
+ if (Op0 == Op1)
+ return Constant::getNullValue(Op0->getType());
+
// all ones >>a X -> all ones
if (match(Op0, m_AllOnes()))
return Op0;
@@ -1730,7 +1739,7 @@ static Constant *computePointerICmp(const DataLayout *TD,
RHS = RHS->stripPointerCasts();
// A non-null pointer is not equal to a null pointer.
- if (llvm::isKnownNonNull(LHS) && isa<ConstantPointerNull>(RHS) &&
+ if (llvm::isKnownNonNull(LHS, TLI) && isa<ConstantPointerNull>(RHS) &&
(Pred == CmpInst::ICMP_EQ || Pred == CmpInst::ICMP_NE))
return ConstantInt::get(GetCompareTy(LHS),
!CmpInst::isTrueWhenEqual(Pred));
@@ -1830,6 +1839,17 @@ static Constant *computePointerICmp(const DataLayout *TD,
return ConstantInt::get(GetCompareTy(LHS),
!CmpInst::isTrueWhenEqual(Pred));
}
+
+ // Even if an non-inbounds GEP occurs along the path we can still optimize
+ // equality comparisons concerning the result. We avoid walking the whole
+ // chain again by starting where the last calls to
+ // stripAndComputeConstantOffsets left off and accumulate the offsets.
+ Constant *LHSNoBound = stripAndComputeConstantOffsets(TD, LHS, true);
+ Constant *RHSNoBound = stripAndComputeConstantOffsets(TD, RHS, true);
+ if (LHS == RHS)
+ return ConstantExpr::getICmp(Pred,
+ ConstantExpr::getAdd(LHSOffset, LHSNoBound),
+ ConstantExpr::getAdd(RHSOffset, RHSNoBound));
}
// Otherwise, fail.
@@ -2026,7 +2046,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
// Turn icmp (ptrtoint x), (ptrtoint/constant) into a compare of the input
// if the integer type is the same size as the pointer type.
if (MaxRecurse && Q.TD && isa<PtrToIntInst>(LI) &&
- Q.TD->getPointerSizeInBits() == DstTy->getPrimitiveSizeInBits()) {
+ Q.TD->getTypeSizeInBits(SrcTy) == DstTy->getPrimitiveSizeInBits()) {
if (Constant *RHSC = dyn_cast<Constant>(RHS)) {
// Transfer the cast to the constant.
if (Value *V = SimplifyICmpInst(Pred, SrcOp,
@@ -2238,6 +2258,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
}
}
+ // icmp pred (urem X, Y), Y
if (LBO && match(LBO, m_URem(m_Value(), m_Specific(RHS)))) {
bool KnownNonNegative, KnownNegative;
switch (Pred) {
@@ -2245,7 +2266,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
break;
case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_SGE:
- ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD);
+ ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD);
if (!KnownNonNegative)
break;
// fall-through
@@ -2255,7 +2276,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
return getFalse(ITy);
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_SLE:
- ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD);
+ ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD);
if (!KnownNonNegative)
break;
// fall-through
@@ -2265,6 +2286,8 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
return getTrue(ITy);
}
}
+
+ // icmp pred X, (urem Y, X)
if (RBO && match(RBO, m_URem(m_Value(), m_Specific(LHS)))) {
bool KnownNonNegative, KnownNegative;
switch (Pred) {
@@ -2272,7 +2295,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
break;
case ICmpInst::ICMP_SGT:
case ICmpInst::ICMP_SGE:
- ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD);
+ ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD);
if (!KnownNonNegative)
break;
// fall-through
@@ -2282,7 +2305,7 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
return getTrue(ITy);
case ICmpInst::ICMP_SLT:
case ICmpInst::ICMP_SLE:
- ComputeSignBit(RHS, KnownNonNegative, KnownNegative, Q.TD);
+ ComputeSignBit(LHS, KnownNonNegative, KnownNegative, Q.TD);
if (!KnownNonNegative)
break;
// fall-through
@@ -2936,6 +2959,7 @@ static bool IsIdempotent(Intrinsic::ID ID) {
case Intrinsic::trunc:
case Intrinsic::rint:
case Intrinsic::nearbyint:
+ case Intrinsic::round:
return true;
}
}
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