Add a GEPOperator class, and move the hasNoPointerOverflow

accessors into it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76245 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-07-17 21:33:58 +00:00
parent afa709d90b
commit 5c2cb324d8
3 changed files with 40 additions and 21 deletions

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@ -573,24 +573,6 @@ public:
/// a constant offset between them.
bool hasAllConstantIndices() const;
/// hasNoPointerOverflow - Return true if this GetElementPtr is known to
/// never have overflow in the pointer addition portions of its effective
/// computation. GetElementPtr computation involves several phases;
/// overflow can be considered to occur in index typecasting, array index
/// scaling, and the addition of the base pointer with offsets. This flag
/// only applies to the last of these. The operands are added to the base
/// pointer one at a time from left to right. This function returns false
/// if any of these additions results in an address value which is not
/// known to be within the allocated address space that the base pointer
/// points into, or within one element (of the original allocation) past
/// the end.
bool hasNoPointerOverflow() const {
return SubclassOptionalData & (1 << 0);
}
void setHasNoPointerOverflow(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0);
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const GetElementPtrInst *) { return true; }
static inline bool classof(const Instruction *I) {

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@ -127,6 +127,41 @@ public:
}
};
class GEPOperator : public Operator {
public:
/// hasNoPointerOverflow - Return true if this GetElementPtr is known to
/// never have overflow in the pointer addition portions of its effective
/// computation. GetElementPtr computation involves several phases;
/// overflow can be considered to occur in index typecasting, array index
/// scaling, and the addition of the base pointer with offsets. This flag
/// only applies to the last of these. The operands are added to the base
/// pointer one at a time from left to right. This function returns false
/// if any of these additions results in an address value which is not
/// known to be within the allocated address space that the base pointer
/// points into, or within one element (of the original allocation) past
/// the end.
bool hasNoPointerOverflow() const {
return SubclassOptionalData & (1 << 0);
}
void setHasNoPointerOverflow(bool B) {
SubclassOptionalData = (SubclassOptionalData & ~(1 << 0)) | (B << 0);
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const GEPOperator *) { return true; }
static inline bool classof(const GetElementPtrInst *) { return true; }
static inline bool classof(const ConstantExpr *CE) {
return CE->getOpcode() == Instruction::GetElementPtr;
}
static inline bool classof(const Instruction *I) {
return I->getOpcode() == Instruction::GetElementPtr;
}
static inline bool classof(const Value *V) {
return isa<GetElementPtrInst>(V) ||
(isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V)));
}
};
} // End llvm namespace
#endif

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@ -16,6 +16,7 @@
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Instructions.h"
#include "llvm/Operator.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/ConstantRange.h"
@ -1024,7 +1025,7 @@ void GetElementPtrInst::init(Value *Ptr, Value* const *Idx, unsigned NumIdx,
setName(Name);
// GetElementPtr instructions have undefined results on overflow by default.
setHasNoPointerOverflow(true);
cast<GEPOperator>(this)->setHasNoPointerOverflow(true);
}
void GetElementPtrInst::init(Value *Ptr, Value *Idx, const std::string &Name) {
@ -1036,7 +1037,7 @@ void GetElementPtrInst::init(Value *Ptr, Value *Idx, const std::string &Name) {
setName(Name);
// GetElementPtr instructions have undefined results on overflow by default.
setHasNoPointerOverflow(true);
cast<GEPOperator>(this)->setHasNoPointerOverflow(true);
}
GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI)
@ -1050,7 +1051,8 @@ GetElementPtrInst::GetElementPtrInst(const GetElementPtrInst &GEPI)
OL[i] = GEPIOL[i];
// Transfer the hasNoPointerOverflow() value from the original GEPI.
setHasNoPointerOverflow(GEPI.hasNoPointerOverflow());
cast<GEPOperator>(this)
->setHasNoPointerOverflow(cast<GEPOperator>(GEPI).hasNoPointerOverflow());
}
GetElementPtrInst::GetElementPtrInst(Value *Ptr, Value *Idx,