Do not use index type to determine what it is indexing into!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10226 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2003-11-25 21:09:18 +00:00
parent 23e907082a
commit be883a23ed

View File

@ -26,6 +26,7 @@
#include "llvm/Pass.h"
#include "llvm/iMemory.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Transforms/Utils/PromoteMemToReg.h"
#include "Support/Debug.h"
@ -222,35 +223,34 @@ bool SROA::performScalarRepl(Function &F) {
/// aggregate allocation.
///
bool SROA::isSafeUseOfAllocation(Instruction *User) {
if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(User)) {
// The GEP is safe to transform if it is of the form GEP <ptr>, 0, <cst>
if (GEPI->getNumOperands() <= 2 ||
GEPI->getOperand(1) != Constant::getNullValue(Type::LongTy) ||
!isa<Constant>(GEPI->getOperand(2)) ||
isa<ConstantExpr>(GEPI->getOperand(2)))
if (!isa<GetElementPtrInst>(User)) return false;
GetElementPtrInst *GEPI = cast<GetElementPtrInst>(User);
gep_type_iterator I = gep_type_begin(GEPI), E = gep_type_end(GEPI);
// The GEP is safe to transform if it is of the form GEP <ptr>, 0, <cst>
if (I == E ||
I.getOperand() != Constant::getNullValue(I.getOperand()->getType()))
return false;
++I;
if (I != E || !isa<ConstantInt>(I.getOperand()))
return false;
// If this is a use of an array allocation, do a bit more checking for sanity.
if (const ArrayType *AT = dyn_cast<ArrayType>(*I)) {
uint64_t NumElements = AT->getNumElements();
// Check to make sure that index falls within the array. If not,
// something funny is going on, so we won't do the optimization.
//
if (cast<ConstantInt>(GEPI->getOperand(2))->getRawValue() >= NumElements)
return false;
// If this is a use of an array allocation, do a bit more checking for
// sanity.
if (GEPI->getOperand(2)->getType() == Type::LongTy) {
const PointerType *PTy =cast<PointerType>(GEPI->getOperand(0)->getType());
const ArrayType *AT = cast<ArrayType>(PTy->getElementType());
int64_t NumElements = AT->getNumElements();
// Check to make sure that index falls within the array. If not,
// something funny is going on, so we won't do the optimization.
//
if (cast<ConstantSInt>(GEPI->getOperand(2))->getValue() >= NumElements ||
cast<ConstantSInt>(GEPI->getOperand(2))->getValue() < 0)
return false;
}
// If there are any non-simple uses of this getelementptr, make sure to
// reject them.
if (isSafeElementUse(GEPI))
return true;
}
return false;
// If there are any non-simple uses of this getelementptr, make sure to reject
// them.
return isSafeElementUse(GEPI);
}
/// isSafeElementUse - Check to see if this use is an allowed use for a