#include "llvm/IR/Operator.h"
+#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Type.h"
return I->getSourceElementType();
return cast<GetElementPtrConstantExpr>(this)->getSourceElementType();
}
+
+bool GEPOperator::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;
+}
}