namespace llvm {
+class APInt;
class ConstantInt;
class ConstantRange;
-class APInt;
+class DataLayout;
class LLVMContext;
enum AtomicOrdering {
/// isInBounds - Determine whether the GEP has the inbounds flag.
bool isInBounds() const;
+ /// \brief Accumulate the constant address offset of this GEP if possible.
+ ///
+ /// This routine accepts an APInt into which it will accumulate the constant
+ /// offset of this GEP if the GEP is in fact constant. If the GEP is not
+ /// all-constant, it returns false and the value of the offset APInt is
+ /// undefined (it is *not* preserved!). The APInt passed into this routine
+ /// must be at least as wide as the IntPtr type for the address space of
+ /// the base GEP pointer.
+ bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const;
+
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Instruction *I) {
return (I->getOpcode() == Instruction::GetElementPtr);
if (!IsOffsetKnown)
return false;
- for (gep_type_iterator GTI = gep_type_begin(GEPI), GTE = gep_type_end(GEPI);
- GTI != GTE; ++GTI) {
- ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
- 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 = DL.getStructLayout(STy);
- Offset += APInt(Offset.getBitWidth(),
- SL->getElementOffset(ElementIdx));
- continue;
- }
-
- // For array or vector indices, scale the index by the size of the type.
- APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth());
- Offset += Index * APInt(Offset.getBitWidth(),
- DL.getTypeAllocSize(GTI.getIndexedType()));
- }
- return true;
+ return GEPI.accumulateConstantOffset(DL, Offset);
}
#include "llvm/Instructions.h"
#include "LLVMContextImpl.h"
#include "llvm/Constants.h"
+#include "llvm/DataLayout.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Module.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Support/ConstantRange.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
return cast<GEPOperator>(this)->isInBounds();
}
+bool GetElementPtrInst::accumulateConstantOffset(const DataLayout &DL,
+ APInt &Offset) const {
+ assert(Offset.getBitWidth() ==
+ DL.getPointerSizeInBits(getPointerAddressSpace()) &&
+ "The offset must have exactly as many bits as our pointer.");
+
+ for (gep_type_iterator GTI = gep_type_begin(this), GTE = gep_type_end(this);
+ GTI != GTE; ++GTI) {
+ ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
+ 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 = DL.getStructLayout(STy);
+ Offset += APInt(Offset.getBitWidth(),
+ SL->getElementOffset(ElementIdx));
+ continue;
+ }
+
+ // For array or vector indices, scale the index by the size of the type.
+ APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth());
+ Offset += Index * APInt(Offset.getBitWidth(),
+ DL.getTypeAllocSize(GTI.getIndexedType()));
+ }
+ return true;
+}
+
//===----------------------------------------------------------------------===//
// ExtractElementInst Implementation
//===----------------------------------------------------------------------===//