#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
-#include "llvm/System/FEnv.h"
+#include "llvm/Support/FEnv.h"
#include <cerrno>
#include <cmath>
using namespace llvm;
for (unsigned i = 1; i != NumOps; ++i) {
if ((i == 1 ||
!isa<StructType>(GetElementPtrInst::getIndexedType(Ops[0]->getType(),
- reinterpret_cast<Value *const *>(Ops+1),
+ reinterpret_cast<Value *const *>(Ops+1),
i-1))) &&
Ops[i]->getType() != IntPtrTy) {
Any = true;
APInt BasePtr(BitWidth, 0);
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Ptr))
if (CE->getOpcode() == Instruction::IntToPtr)
- if (ConstantInt *Base = dyn_cast<ConstantInt>(CE->getOperand(0))) {
- BasePtr = Base->getValue();
- BasePtr.zextOrTrunc(BitWidth);
- }
+ if (ConstantInt *Base = dyn_cast<ConstantInt>(CE->getOperand(0)))
+ BasePtr = Base->getValue().zextOrTrunc(BitWidth);
if (Ptr->isNullValue() || BasePtr != 0) {
Constant *C = ConstantInt::get(Ptr->getContext(), Offset+BasePtr);
return ConstantExpr::getIntToPtr(C, ResultTy);
// Determine which element of the array the offset points into.
APInt ElemSize(BitWidth, TD->getTypeAllocSize(ATy->getElementType()));
+ const IntegerType *IntPtrTy = TD->getIntPtrType(Ty->getContext());
if (ElemSize == 0)
- return 0;
- APInt NewIdx = Offset.udiv(ElemSize);
- Offset -= NewIdx * ElemSize;
- NewIdxs.push_back(ConstantInt::get(TD->getIntPtrType(Ty->getContext()),
- NewIdx));
+ // The element size is 0. This may be [0 x Ty]*, so just use a zero
+ // index for this level and proceed to the next level to see if it can
+ // accommodate the offset.
+ NewIdxs.push_back(ConstantInt::get(IntPtrTy, 0));
+ else {
+ // The element size is non-zero divide the offset by the element
+ // size (rounding down), to compute the index at this level.
+ APInt NewIdx = Offset.udiv(ElemSize);
+ Offset -= NewIdx * ElemSize;
+ NewIdxs.push_back(ConstantInt::get(IntPtrTy, NewIdx));
+ }
Ty = ATy->getElementType();
} else if (const StructType *STy = dyn_cast<StructType>(Ty)) {
// Determine which field of the struct the offset points into. The
// Constant Folding public APIs
//===----------------------------------------------------------------------===//
-
-/// ConstantFoldInstruction - Attempt to constant fold the specified
-/// instruction. If successful, the constant result is returned, if not, null
-/// is returned. Note that this function can only fail when attempting to fold
-/// instructions like loads and stores, which have no constant expression form.
-///
+/// ConstantFoldInstruction - Try to constant fold the specified instruction.
+/// If successful, the constant result is returned, if not, null is returned.
+/// 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) {
- // Handle PHI nodes specially here...
+ // Handle PHI nodes quickly here...
if (PHINode *PN = dyn_cast<PHINode>(I)) {
Constant *CommonValue = 0;
for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
Value *Incoming = PN->getIncomingValue(i);
- // If the incoming value is equal to the phi node itself or is undef then
- // skip it.
- if (Incoming == PN || isa<UndefValue>(Incoming))
+ // If the incoming value is undef then skip it. Note that while we could
+ // skip the value if it is equal to the phi node itself we choose not to
+ // because that would break the rule that constant folding only applies if
+ // all operands are constants.
+ if (isa<UndefValue>(Incoming))
continue;
// If the incoming value is not a constant, or is a different constant to
// the one we saw previously, then give up.
if (const LoadInst *LI = dyn_cast<LoadInst>(I))
return ConstantFoldLoadInst(LI, TD);
-
+
+ if (InsertValueInst *IVI = dyn_cast<InsertValueInst>(I))
+ return ConstantExpr::getInsertValue(
+ cast<Constant>(IVI->getAggregateOperand()),
+ cast<Constant>(IVI->getInsertedValueOperand()),
+ IVI->idx_begin(), IVI->getNumIndices());
+
+ if (ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(I))
+ return ConstantExpr::getExtractValue(
+ cast<Constant>(EVI->getAggregateOperand()),
+ EVI->idx_begin(), EVI->getNumIndices());
+
return ConstantFoldInstOperands(I->getOpcode(), I->getType(),
Ops.data(), Ops.size(), TD);
}
Constant *llvm::ConstantFoldConstantExpression(const ConstantExpr *CE,
const TargetData *TD) {
SmallVector<Constant*, 8> Ops;
- for (User::const_op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i) {
+ 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))