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-rw-r--r--lib/Analysis/ConstantFolding.cpp133
1 files changed, 77 insertions, 56 deletions
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index df79849..8e2f263 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -26,6 +26,7 @@
#include "llvm/Operator.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetLibraryInfo.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/Support/ErrorHandling.h"
@@ -542,8 +543,8 @@ static Constant *SymbolicallyEvaluateBinop(unsigned Opc, Constant *Op0,
/// explicitly cast them so that they aren't implicitly casted by the
/// getelementptr.
static Constant *CastGEPIndices(ArrayRef<Constant *> Ops,
- Type *ResultTy,
- const TargetData *TD) {
+ Type *ResultTy, const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
if (!TD) return 0;
Type *IntPtrTy = TD->getIntPtrType(ResultTy->getContext());
@@ -568,7 +569,7 @@ static Constant *CastGEPIndices(ArrayRef<Constant *> Ops,
Constant *C =
ConstantExpr::getGetElementPtr(Ops[0], NewIdxs);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
- if (Constant *Folded = ConstantFoldConstantExpression(CE, TD))
+ if (Constant *Folded = ConstantFoldConstantExpression(CE, TD, TLI))
C = Folded;
return C;
}
@@ -576,10 +577,11 @@ static Constant *CastGEPIndices(ArrayRef<Constant *> Ops,
/// SymbolicallyEvaluateGEP - If we can symbolically evaluate the specified GEP
/// constant expression, do so.
static Constant *SymbolicallyEvaluateGEP(ArrayRef<Constant *> Ops,
- Type *ResultTy,
- const TargetData *TD) {
+ Type *ResultTy, const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
Constant *Ptr = Ops[0];
- if (!TD || !cast<PointerType>(Ptr->getType())->getElementType()->isSized())
+ if (!TD || !cast<PointerType>(Ptr->getType())->getElementType()->isSized() ||
+ !Ptr->getType()->isPointerTy())
return 0;
Type *IntPtrTy = TD->getIntPtrType(Ptr->getContext());
@@ -602,7 +604,7 @@ static Constant *SymbolicallyEvaluateGEP(ArrayRef<Constant *> Ops,
Res = ConstantExpr::getSub(Res, CE->getOperand(1));
Res = ConstantExpr::getIntToPtr(Res, ResultTy);
if (ConstantExpr *ResCE = dyn_cast<ConstantExpr>(Res))
- Res = ConstantFoldConstantExpression(ResCE, TD);
+ Res = ConstantFoldConstantExpression(ResCE, TD, TLI);
return Res;
}
}
@@ -729,7 +731,9 @@ static Constant *SymbolicallyEvaluateGEP(ArrayRef<Constant *> Ops,
/// Note that this fails if not all of the operands are constant. Otherwise,
/// this function can only fail when attempting to fold instructions like loads
/// and stores, which have no constant expression form.
-Constant *llvm::ConstantFoldInstruction(Instruction *I, const TargetData *TD) {
+Constant *llvm::ConstantFoldInstruction(Instruction *I,
+ const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
// Handle PHI nodes quickly here...
if (PHINode *PN = dyn_cast<PHINode>(I)) {
Constant *CommonValue = 0;
@@ -765,7 +769,7 @@ Constant *llvm::ConstantFoldInstruction(Instruction *I, const TargetData *TD) {
if (const CmpInst *CI = dyn_cast<CmpInst>(I))
return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
- TD);
+ TD, TLI);
if (const LoadInst *LI = dyn_cast<LoadInst>(I))
return ConstantFoldLoadInst(LI, TD);
@@ -781,28 +785,29 @@ Constant *llvm::ConstantFoldInstruction(Instruction *I, const TargetData *TD) {
cast<Constant>(EVI->getAggregateOperand()),
EVI->getIndices());
- return ConstantFoldInstOperands(I->getOpcode(), I->getType(), Ops, TD);
+ return ConstantFoldInstOperands(I->getOpcode(), I->getType(), Ops, TD, TLI);
}
/// ConstantFoldConstantExpression - Attempt to fold the constant expression
/// using the specified TargetData. If successful, the constant result is
/// result is returned, if not, null is returned.
Constant *llvm::ConstantFoldConstantExpression(const ConstantExpr *CE,
- const TargetData *TD) {
+ const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
SmallVector<Constant*, 8> Ops;
for (User::const_op_iterator i = CE->op_begin(), e = CE->op_end();
i != e; ++i) {
Constant *NewC = cast<Constant>(*i);
// Recursively fold the ConstantExpr's operands.
if (ConstantExpr *NewCE = dyn_cast<ConstantExpr>(NewC))
- NewC = ConstantFoldConstantExpression(NewCE, TD);
+ NewC = ConstantFoldConstantExpression(NewCE, TD, TLI);
Ops.push_back(NewC);
}
if (CE->isCompare())
return ConstantFoldCompareInstOperands(CE->getPredicate(), Ops[0], Ops[1],
- TD);
- return ConstantFoldInstOperands(CE->getOpcode(), CE->getType(), Ops, TD);
+ TD, TLI);
+ return ConstantFoldInstOperands(CE->getOpcode(), CE->getType(), Ops, TD, TLI);
}
/// ConstantFoldInstOperands - Attempt to constant fold an instruction with the
@@ -817,7 +822,8 @@ Constant *llvm::ConstantFoldConstantExpression(const ConstantExpr *CE,
///
Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
ArrayRef<Constant *> Ops,
- const TargetData *TD) {
+ const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
// Handle easy binops first.
if (Instruction::isBinaryOp(Opcode)) {
if (isa<ConstantExpr>(Ops[0]) || isa<ConstantExpr>(Ops[1]))
@@ -834,7 +840,7 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
case Instruction::Call:
if (Function *F = dyn_cast<Function>(Ops.back()))
if (canConstantFoldCallTo(F))
- return ConstantFoldCall(F, Ops.slice(0, Ops.size() - 1));
+ return ConstantFoldCall(F, Ops.slice(0, Ops.size() - 1), TLI);
return 0;
case Instruction::PtrToInt:
// If the input is a inttoptr, eliminate the pair. This requires knowing
@@ -888,9 +894,9 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
case Instruction::ShuffleVector:
return ConstantExpr::getShuffleVector(Ops[0], Ops[1], Ops[2]);
case Instruction::GetElementPtr:
- if (Constant *C = CastGEPIndices(Ops, DestTy, TD))
+ if (Constant *C = CastGEPIndices(Ops, DestTy, TD, TLI))
return C;
- if (Constant *C = SymbolicallyEvaluateGEP(Ops, DestTy, TD))
+ if (Constant *C = SymbolicallyEvaluateGEP(Ops, DestTy, TD, TLI))
return C;
return ConstantExpr::getGetElementPtr(Ops[0], Ops.slice(1));
@@ -903,7 +909,8 @@ Constant *llvm::ConstantFoldInstOperands(unsigned Opcode, Type *DestTy,
///
Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
Constant *Ops0, Constant *Ops1,
- const TargetData *TD) {
+ const TargetData *TD,
+ const TargetLibraryInfo *TLI) {
// fold: icmp (inttoptr x), null -> icmp x, 0
// fold: icmp (ptrtoint x), 0 -> icmp x, null
// fold: icmp (inttoptr x), (inttoptr y) -> icmp trunc/zext x, trunc/zext y
@@ -920,7 +927,7 @@ Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
Constant *C = ConstantExpr::getIntegerCast(CE0->getOperand(0),
IntPtrTy, false);
Constant *Null = Constant::getNullValue(C->getType());
- return ConstantFoldCompareInstOperands(Predicate, C, Null, TD);
+ return ConstantFoldCompareInstOperands(Predicate, C, Null, TD, TLI);
}
// Only do this transformation if the int is intptrty in size, otherwise
@@ -929,7 +936,7 @@ Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
CE0->getType() == IntPtrTy) {
Constant *C = CE0->getOperand(0);
Constant *Null = Constant::getNullValue(C->getType());
- return ConstantFoldCompareInstOperands(Predicate, C, Null, TD);
+ return ConstantFoldCompareInstOperands(Predicate, C, Null, TD, TLI);
}
}
@@ -944,7 +951,7 @@ Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
IntPtrTy, false);
Constant *C1 = ConstantExpr::getIntegerCast(CE1->getOperand(0),
IntPtrTy, false);
- return ConstantFoldCompareInstOperands(Predicate, C0, C1, TD);
+ return ConstantFoldCompareInstOperands(Predicate, C0, C1, TD, TLI);
}
// Only do this transformation if the int is intptrty in size, otherwise
@@ -953,7 +960,7 @@ Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
CE0->getType() == IntPtrTy &&
CE0->getOperand(0)->getType() == CE1->getOperand(0)->getType()))
return ConstantFoldCompareInstOperands(Predicate, CE0->getOperand(0),
- CE1->getOperand(0), TD);
+ CE1->getOperand(0), TD, TLI);
}
}
@@ -962,13 +969,15 @@ Constant *llvm::ConstantFoldCompareInstOperands(unsigned Predicate,
if ((Predicate == ICmpInst::ICMP_EQ || Predicate == ICmpInst::ICMP_NE) &&
CE0->getOpcode() == Instruction::Or && Ops1->isNullValue()) {
Constant *LHS =
- ConstantFoldCompareInstOperands(Predicate, CE0->getOperand(0), Ops1,TD);
+ ConstantFoldCompareInstOperands(Predicate, CE0->getOperand(0), Ops1,
+ TD, TLI);
Constant *RHS =
- ConstantFoldCompareInstOperands(Predicate, CE0->getOperand(1), Ops1,TD);
+ ConstantFoldCompareInstOperands(Predicate, CE0->getOperand(1), Ops1,
+ TD, TLI);
unsigned OpC =
Predicate == ICmpInst::ICMP_EQ ? Instruction::And : Instruction::Or;
Constant *Ops[] = { LHS, RHS };
- return ConstantFoldInstOperands(OpC, LHS->getType(), Ops, TD);
+ return ConstantFoldInstOperands(OpC, LHS->getType(), Ops, TD, TLI);
}
}
@@ -1045,6 +1054,7 @@ bool
llvm::canConstantFoldCallTo(const Function *F) {
switch (F->getIntrinsicID()) {
case Intrinsic::sqrt:
+ case Intrinsic::pow:
case Intrinsic::powi:
case Intrinsic::bswap:
case Intrinsic::ctpop:
@@ -1168,7 +1178,8 @@ static Constant *ConstantFoldConvertToInt(ConstantFP *Op, bool roundTowardZero,
/// ConstantFoldCall - Attempt to constant fold a call to the specified function
/// with the specified arguments, returning null if unsuccessful.
Constant *
-llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
+llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands,
+ const TargetLibraryInfo *TLI) {
if (!F->hasName()) return 0;
StringRef Name = F->getName();
@@ -1183,6 +1194,8 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
return ConstantInt::get(F->getContext(), Val.bitcastToAPInt());
}
+ if (!TLI)
+ return 0;
if (!Ty->isFloatTy() && !Ty->isDoubleTy())
return 0;
@@ -1201,43 +1214,43 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
Op->getValueAPF().convertToDouble();
switch (Name[0]) {
case 'a':
- if (Name == "acos")
+ if (Name == "acos" && TLI->has(LibFunc::acos))
return ConstantFoldFP(acos, V, Ty);
- else if (Name == "asin")
+ else if (Name == "asin" && TLI->has(LibFunc::asin))
return ConstantFoldFP(asin, V, Ty);
- else if (Name == "atan")
+ else if (Name == "atan" && TLI->has(LibFunc::atan))
return ConstantFoldFP(atan, V, Ty);
break;
case 'c':
- if (Name == "ceil")
+ if (Name == "ceil" && TLI->has(LibFunc::ceil))
return ConstantFoldFP(ceil, V, Ty);
- else if (Name == "cos")
+ else if (Name == "cos" && TLI->has(LibFunc::cos))
return ConstantFoldFP(cos, V, Ty);
- else if (Name == "cosh")
+ else if (Name == "cosh" && TLI->has(LibFunc::cosh))
return ConstantFoldFP(cosh, V, Ty);
- else if (Name == "cosf")
+ else if (Name == "cosf" && TLI->has(LibFunc::cosf))
return ConstantFoldFP(cos, V, Ty);
break;
case 'e':
- if (Name == "exp")
+ if (Name == "exp" && TLI->has(LibFunc::exp))
return ConstantFoldFP(exp, V, Ty);
- if (Name == "exp2") {
+ if (Name == "exp2" && TLI->has(LibFunc::exp2)) {
// Constant fold exp2(x) as pow(2,x) in case the host doesn't have a
// C99 library.
return ConstantFoldBinaryFP(pow, 2.0, V, Ty);
}
break;
case 'f':
- if (Name == "fabs")
+ if (Name == "fabs" && TLI->has(LibFunc::fabs))
return ConstantFoldFP(fabs, V, Ty);
- else if (Name == "floor")
+ else if (Name == "floor" && TLI->has(LibFunc::floor))
return ConstantFoldFP(floor, V, Ty);
break;
case 'l':
- if (Name == "log" && V > 0)
+ if (Name == "log" && V > 0 && TLI->has(LibFunc::log))
return ConstantFoldFP(log, V, Ty);
- else if (Name == "log10" && V > 0)
+ else if (Name == "log10" && V > 0 && TLI->has(LibFunc::log10))
return ConstantFoldFP(log10, V, Ty);
else if (F->getIntrinsicID() == Intrinsic::sqrt &&
(Ty->isFloatTy() || Ty->isDoubleTy())) {
@@ -1248,21 +1261,21 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
}
break;
case 's':
- if (Name == "sin")
+ if (Name == "sin" && TLI->has(LibFunc::sin))
return ConstantFoldFP(sin, V, Ty);
- else if (Name == "sinh")
+ else if (Name == "sinh" && TLI->has(LibFunc::sinh))
return ConstantFoldFP(sinh, V, Ty);
- else if (Name == "sqrt" && V >= 0)
+ else if (Name == "sqrt" && V >= 0 && TLI->has(LibFunc::sqrt))
return ConstantFoldFP(sqrt, V, Ty);
- else if (Name == "sqrtf" && V >= 0)
+ else if (Name == "sqrtf" && V >= 0 && TLI->has(LibFunc::sqrtf))
return ConstantFoldFP(sqrt, V, Ty);
- else if (Name == "sinf")
+ else if (Name == "sinf" && TLI->has(LibFunc::sinf))
return ConstantFoldFP(sin, V, Ty);
break;
case 't':
- if (Name == "tan")
+ if (Name == "tan" && TLI->has(LibFunc::tan))
return ConstantFoldFP(tan, V, Ty);
- else if (Name == "tanh")
+ else if (Name == "tanh" && TLI->has(LibFunc::tanh))
return ConstantFoldFP(tanh, V, Ty);
break;
default:
@@ -1277,10 +1290,6 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
return ConstantInt::get(F->getContext(), Op->getValue().byteSwap());
case Intrinsic::ctpop:
return ConstantInt::get(Ty, Op->getValue().countPopulation());
- case Intrinsic::cttz:
- return ConstantInt::get(Ty, Op->getValue().countTrailingZeros());
- case Intrinsic::ctlz:
- return ConstantInt::get(Ty, Op->getValue().countLeadingZeros());
case Intrinsic::convert_from_fp16: {
APFloat Val(Op->getValue());
@@ -1337,16 +1346,21 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
if (ConstantFP *Op2 = dyn_cast<ConstantFP>(Operands[1])) {
if (Op2->getType() != Op1->getType())
return 0;
-
+
double Op2V = Ty->isFloatTy() ?
(double)Op2->getValueAPF().convertToFloat():
Op2->getValueAPF().convertToDouble();
- if (Name == "pow")
+ if (F->getIntrinsicID() == Intrinsic::pow) {
return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
- if (Name == "fmod")
+ }
+ if (!TLI)
+ return 0;
+ if (Name == "pow" && TLI->has(LibFunc::pow))
+ return ConstantFoldBinaryFP(pow, Op1V, Op2V, Ty);
+ if (Name == "fmod" && TLI->has(LibFunc::fmod))
return ConstantFoldBinaryFP(fmod, Op1V, Op2V, Ty);
- if (Name == "atan2")
+ if (Name == "atan2" && TLI->has(LibFunc::atan2))
return ConstantFoldBinaryFP(atan2, Op1V, Op2V, Ty);
} else if (ConstantInt *Op2C = dyn_cast<ConstantInt>(Operands[1])) {
if (F->getIntrinsicID() == Intrinsic::powi && Ty->isFloatTy())
@@ -1361,7 +1375,6 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
return 0;
}
-
if (ConstantInt *Op1 = dyn_cast<ConstantInt>(Operands[0])) {
if (ConstantInt *Op2 = dyn_cast<ConstantInt>(Operands[1])) {
switch (F->getIntrinsicID()) {
@@ -1401,6 +1414,14 @@ llvm::ConstantFoldCall(Function *F, ArrayRef<Constant *> Operands) {
};
return ConstantStruct::get(cast<StructType>(F->getReturnType()), Ops);
}
+ case Intrinsic::cttz:
+ // FIXME: This should check for Op2 == 1, and become unreachable if
+ // Op1 == 0.
+ return ConstantInt::get(Ty, Op1->getValue().countTrailingZeros());
+ case Intrinsic::ctlz:
+ // FIXME: This should check for Op2 == 1, and become unreachable if
+ // Op1 == 0.
+ return ConstantInt::get(Ty, Op1->getValue().countLeadingZeros());
}
}
generated by cgit v1.1 at 2025-06-26 12:44:53 +0000