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-rw-r--r--lib/Analysis/InstructionSimplify.cpp225
1 files changed, 170 insertions, 55 deletions
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 00689475a4..d97e226c3a 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -25,9 +25,9 @@
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/DataLayout.h"
-#include "llvm/GlobalAlias.h"
-#include "llvm/Operator.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/Operator.h"
#include "llvm/Support/ConstantRange.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/PatternMatch.h"
@@ -657,39 +657,6 @@ Value *llvm::SimplifyAddInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW,
RecursionLimit);
}
-/// \brief Accumulate the constant integer offset a GEP represents.
-///
-/// Given a getelementptr instruction/constantexpr, accumulate the constant
-/// offset from the base pointer into the provided APInt 'Offset'. Returns true
-/// if the GEP has all-constant indices. Returns false if any non-constant
-/// index is encountered leaving the 'Offset' in an undefined state. The
-/// 'Offset' APInt must be the bitwidth of the target's pointer size.
-static bool accumulateGEPOffset(const DataLayout &TD, GEPOperator *GEP,
- APInt &Offset) {
- unsigned IntPtrWidth = TD.getPointerSizeInBits();
- assert(IntPtrWidth == Offset.getBitWidth());
-
- gep_type_iterator GTI = gep_type_begin(GEP);
- for (User::op_iterator I = GEP->op_begin() + 1, E = GEP->op_end(); I != E;
- ++I, ++GTI) {
- ConstantInt *OpC = dyn_cast<ConstantInt>(*I);
- if (!OpC) return false;
- if (OpC->isZero()) continue;
-
- // Handle a struct index, which adds its field offset to the pointer.
- if (StructType *STy = dyn_cast<StructType>(*GTI)) {
- unsigned ElementIdx = OpC->getZExtValue();
- const StructLayout *SL = TD.getStructLayout(STy);
- Offset += APInt(IntPtrWidth, SL->getElementOffset(ElementIdx));
- continue;
- }
-
- APInt TypeSize(IntPtrWidth, TD.getTypeAllocSize(GTI.getIndexedType()));
- Offset += OpC->getValue().sextOrTrunc(IntPtrWidth) * TypeSize;
- }
- return true;
-}
-
/// \brief Compute the base pointer and cumulative constant offsets for V.
///
/// This strips all constant offsets off of V, leaving it the base pointer, and
@@ -710,7 +677,7 @@ static Constant *stripAndComputeConstantOffsets(const DataLayout &TD,
Visited.insert(V);
do {
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
- if (!GEP->isInBounds() || !accumulateGEPOffset(TD, GEP, Offset))
+ if (!GEP->isInBounds() || !GEP->accumulateConstantOffset(TD, Offset))
break;
V = GEP->getPointerOperand();
} else if (Operator::getOpcode(V) == Instruction::BitCast) {
@@ -886,6 +853,85 @@ Value *llvm::SimplifySubInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW,
RecursionLimit);
}
+/// Given operands for an FAdd, see if we can fold the result. If not, this
+/// returns null.
+static Value *SimplifyFAddInst(Value *Op0, Value *Op1, FastMathFlags FMF,
+ const Query &Q, unsigned MaxRecurse) {
+ if (Constant *CLHS = dyn_cast<Constant>(Op0)) {
+ if (Constant *CRHS = dyn_cast<Constant>(Op1)) {
+ Constant *Ops[] = { CLHS, CRHS };
+ return ConstantFoldInstOperands(Instruction::FAdd, CLHS->getType(),
+ Ops, Q.TD, Q.TLI);
+ }
+
+ // Canonicalize the constant to the RHS.
+ std::swap(Op0, Op1);
+ }
+
+ // fadd X, -0 ==> X
+ if (match(Op1, m_NegZero()))
+ return Op0;
+
+ // fadd X, 0 ==> X, when we know X is not -0
+ if (match(Op1, m_Zero()) &&
+ (FMF.noSignedZeros() || CannotBeNegativeZero(Op0)))
+ return Op0;
+
+ // fadd [nnan ninf] X, (fsub [nnan ninf] 0, X) ==> 0
+ // where nnan and ninf have to occur at least once somewhere in this
+ // expression
+ Value *SubOp = 0;
+ if (match(Op1, m_FSub(m_AnyZero(), m_Specific(Op0))))
+ SubOp = Op1;
+ else if (match(Op0, m_FSub(m_AnyZero(), m_Specific(Op1))))
+ SubOp = Op0;
+ if (SubOp) {
+ Instruction *FSub = cast<Instruction>(SubOp);
+ if ((FMF.noNaNs() || FSub->hasNoNaNs()) &&
+ (FMF.noInfs() || FSub->hasNoInfs()))
+ return Constant::getNullValue(Op0->getType());
+ }
+
+ return 0;
+}
+
+/// Given operands for an FSub, see if we can fold the result. If not, this
+/// returns null.
+static Value *SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF,
+ const Query &Q, unsigned MaxRecurse) {
+ if (Constant *CLHS = dyn_cast<Constant>(Op0)) {
+ if (Constant *CRHS = dyn_cast<Constant>(Op1)) {
+ Constant *Ops[] = { CLHS, CRHS };
+ return ConstantFoldInstOperands(Instruction::FSub, CLHS->getType(),
+ Ops, Q.TD, Q.TLI);
+ }
+ }
+
+ // fsub X, 0 ==> X
+ if (match(Op1, m_Zero()))
+ return Op0;
+
+ // fsub X, -0 ==> X, when we know X is not -0
+ if (match(Op1, m_NegZero()) &&
+ (FMF.noSignedZeros() || CannotBeNegativeZero(Op0)))
+ return Op0;
+
+ // fsub 0, (fsub -0.0, X) ==> X
+ Value *X;
+ if (match(Op0, m_AnyZero())) {
+ if (match(Op1, m_FSub(m_NegZero(), m_Value(X))))
+ return X;
+ if (FMF.noSignedZeros() && match(Op1, m_FSub(m_AnyZero(), m_Value(X))))
+ return X;
+ }
+
+ // fsub nnan ninf x, x ==> 0.0
+ if (FMF.noNaNs() && FMF.noInfs() && Op0 == Op1)
+ return Constant::getNullValue(Op0->getType());
+
+ return 0;
+}
+
/// Given the operands for an FMul, see if we can fold the result
static Value *SimplifyFMulInst(Value *Op0, Value *Op1,
FastMathFlags FMF,
@@ -897,19 +943,19 @@ static Value *SimplifyFMulInst(Value *Op0, Value *Op1,
return ConstantFoldInstOperands(Instruction::FMul, CLHS->getType(),
Ops, Q.TD, Q.TLI);
}
- }
- // Check for some fast-math optimizations
- if (FMF.noNaNs()) {
- if (FMF.noSignedZeros()) {
- // fmul N S 0, x ==> 0
- if (match(Op0, m_Zero()))
- return Op0;
- if (match(Op1, m_Zero()))
- return Op1;
- }
+ // Canonicalize the constant to the RHS.
+ std::swap(Op0, Op1);
}
+ // fmul X, 1.0 ==> X
+ if (match(Op1, m_FPOne()))
+ return Op0;
+
+ // fmul nnan nsz X, 0 ==> 0
+ if (FMF.noNaNs() && FMF.noSignedZeros() && match(Op1, m_AnyZero()))
+ return Op1;
+
return 0;
}
@@ -978,6 +1024,18 @@ static Value *SimplifyMulInst(Value *Op0, Value *Op1, const Query &Q,
return 0;
}
+Value *llvm::SimplifyFAddInst(Value *Op0, Value *Op1, FastMathFlags FMF,
+ const DataLayout *TD, const TargetLibraryInfo *TLI,
+ const DominatorTree *DT) {
+ return ::SimplifyFAddInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit);
+}
+
+Value *llvm::SimplifyFSubInst(Value *Op0, Value *Op1, FastMathFlags FMF,
+ const DataLayout *TD, const TargetLibraryInfo *TLI,
+ const DominatorTree *DT) {
+ return ::SimplifyFSubInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit);
+}
+
Value *llvm::SimplifyFMulInst(Value *Op0, Value *Op1,
FastMathFlags FMF,
const DataLayout *TD,
@@ -1399,9 +1457,9 @@ static Value *SimplifyAndInst(Value *Op0, Value *Op1, const Query &Q,
// A & (-A) = A if A is a power of two or zero.
if (match(Op0, m_Neg(m_Specific(Op1))) ||
match(Op1, m_Neg(m_Specific(Op0)))) {
- if (isPowerOfTwo(Op0, Q.TD, /*OrZero*/true))
+ if (isKnownToBeAPowerOfTwo(Op0, /*OrZero*/true))
return Op0;
- if (isPowerOfTwo(Op1, Q.TD, /*OrZero*/true))
+ if (isKnownToBeAPowerOfTwo(Op1, /*OrZero*/true))
return Op1;
}
@@ -2732,10 +2790,18 @@ static Value *SimplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS,
case Instruction::Add:
return SimplifyAddInst(LHS, RHS, /*isNSW*/false, /*isNUW*/false,
Q, MaxRecurse);
+ case Instruction::FAdd:
+ return SimplifyFAddInst(LHS, RHS, FastMathFlags(), Q, MaxRecurse);
+
case Instruction::Sub:
return SimplifySubInst(LHS, RHS, /*isNSW*/false, /*isNUW*/false,
Q, MaxRecurse);
+ case Instruction::FSub:
+ return SimplifyFSubInst(LHS, RHS, FastMathFlags(), Q, MaxRecurse);
+
case Instruction::Mul: return SimplifyMulInst (LHS, RHS, Q, MaxRecurse);
+ case Instruction::FMul:
+ return SimplifyFMulInst (LHS, RHS, FastMathFlags(), Q, MaxRecurse);
case Instruction::SDiv: return SimplifySDivInst(LHS, RHS, Q, MaxRecurse);
case Instruction::UDiv: return SimplifyUDivInst(LHS, RHS, Q, MaxRecurse);
case Instruction::FDiv: return SimplifyFDivInst(LHS, RHS, Q, MaxRecurse);
@@ -2803,12 +2869,50 @@ Value *llvm::SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
RecursionLimit);
}
-static Value *SimplifyCallInst(CallInst *CI, const Query &) {
+template <typename IterTy>
+static Value *SimplifyCall(Value *V, IterTy ArgBegin, IterTy ArgEnd,
+ const Query &Q, unsigned MaxRecurse) {
+ Type *Ty = V->getType();
+ if (PointerType *PTy = dyn_cast<PointerType>(Ty))
+ Ty = PTy->getElementType();
+ FunctionType *FTy = cast<FunctionType>(Ty);
+
// call undef -> undef
- if (isa<UndefValue>(CI->getCalledValue()))
- return UndefValue::get(CI->getType());
+ if (isa<UndefValue>(V))
+ return UndefValue::get(FTy->getReturnType());
- return 0;
+ Function *F = dyn_cast<Function>(V);
+ if (!F)
+ return 0;
+
+ if (!canConstantFoldCallTo(F))
+ return 0;
+
+ SmallVector<Constant *, 4> ConstantArgs;
+ ConstantArgs.reserve(ArgEnd - ArgBegin);
+ for (IterTy I = ArgBegin, E = ArgEnd; I != E; ++I) {
+ Constant *C = dyn_cast<Constant>(*I);
+ if (!C)
+ return 0;
+ ConstantArgs.push_back(C);
+ }
+
+ return ConstantFoldCall(F, ConstantArgs, Q.TLI);
+}
+
+Value *llvm::SimplifyCall(Value *V, User::op_iterator ArgBegin,
+ User::op_iterator ArgEnd, const DataLayout *TD,
+ const TargetLibraryInfo *TLI,
+ const DominatorTree *DT) {
+ return ::SimplifyCall(V, ArgBegin, ArgEnd, Query(TD, TLI, DT),
+ RecursionLimit);
+}
+
+Value *llvm::SimplifyCall(Value *V, ArrayRef<Value *> Args,
+ const DataLayout *TD, const TargetLibraryInfo *TLI,
+ const DominatorTree *DT) {
+ return ::SimplifyCall(V, Args.begin(), Args.end(), Query(TD, TLI, DT),
+ RecursionLimit);
}
/// SimplifyInstruction - See if we can compute a simplified version of this
@@ -2822,12 +2926,20 @@ Value *llvm::SimplifyInstruction(Instruction *I, const DataLayout *TD,
default:
Result = ConstantFoldInstruction(I, TD, TLI);
break;
+ case Instruction::FAdd:
+ Result = SimplifyFAddInst(I->getOperand(0), I->getOperand(1),
+ I->getFastMathFlags(), TD, TLI, DT);
+ break;
case Instruction::Add:
Result = SimplifyAddInst(I->getOperand(0), I->getOperand(1),
cast<BinaryOperator>(I)->hasNoSignedWrap(),
cast<BinaryOperator>(I)->hasNoUnsignedWrap(),
TD, TLI, DT);
break;
+ case Instruction::FSub:
+ Result = SimplifyFSubInst(I->getOperand(0), I->getOperand(1),
+ I->getFastMathFlags(), TD, TLI, DT);
+ break;
case Instruction::Sub:
Result = SimplifySubInst(I->getOperand(0), I->getOperand(1),
cast<BinaryOperator>(I)->hasNoSignedWrap(),
@@ -2911,9 +3023,12 @@ Value *llvm::SimplifyInstruction(Instruction *I, const DataLayout *TD,
case Instruction::PHI:
Result = SimplifyPHINode(cast<PHINode>(I), Query (TD, TLI, DT));
break;
- case Instruction::Call:
- Result = SimplifyCallInst(cast<CallInst>(I), Query (TD, TLI, DT));
+ case Instruction::Call: {
+ CallSite CS(cast<CallInst>(I));
+ Result = SimplifyCall(CS.getCalledValue(), CS.arg_begin(), CS.arg_end(),
+ TD, TLI, DT);
break;
+ }
case Instruction::Trunc:
Result = SimplifyTruncInst(I->getOperand(0), I->getType(), TD, TLI, DT);
break;