Mercurial > hg > CbC > CbC_llvm

comparison lib/IR/Operator.cpp @ 95:afa8332a0e37 LLVM3.8

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
LLVM 3.8
author Kaito Tokumori <e105711@ie.u-ryukyu.ac.jp>
date Tue, 13 Oct 2015 17:48:58 +0900
parents
children 7d135dc70f03
comparison
equal deleted inserted replaced
84:f3e34b893a5f 95:afa8332a0e37
1 #include "llvm/IR/Operator.h"
2 #include "llvm/IR/GetElementPtrTypeIterator.h"
3 #include "llvm/IR/Instructions.h"
4 #include "llvm/IR/Type.h"
5
6 #include "ConstantsContext.h"
7
8 namespace llvm {
9 Type *GEPOperator::getSourceElementType() const {
10 if (auto *I = dyn_cast<GetElementPtrInst>(this))
11 return I->getSourceElementType();
12 return cast<GetElementPtrConstantExpr>(this)->getSourceElementType();
13 }
14
15 bool GEPOperator::accumulateConstantOffset(const DataLayout &DL,
16 APInt &Offset) const {
17 assert(Offset.getBitWidth() ==
18 DL.getPointerSizeInBits(getPointerAddressSpace()) &&
19 "The offset must have exactly as many bits as our pointer.");
20
21 for (gep_type_iterator GTI = gep_type_begin(this), GTE = gep_type_end(this);
22 GTI != GTE; ++GTI) {
23 ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand());
24 if (!OpC)
25 return false;
26 if (OpC->isZero())
27 continue;
28
29 // Handle a struct index, which adds its field offset to the pointer.
30 if (StructType *STy = dyn_cast<StructType>(*GTI)) {
31 unsigned ElementIdx = OpC->getZExtValue();
32 const StructLayout *SL = DL.getStructLayout(STy);
33 Offset += APInt(Offset.getBitWidth(), SL->getElementOffset(ElementIdx));
34 continue;
35 }
36
37 // For array or vector indices, scale the index by the size of the type.
38 APInt Index = OpC->getValue().sextOrTrunc(Offset.getBitWidth());
39 Offset += Index * APInt(Offset.getBitWidth(),
40 DL.getTypeAllocSize(GTI.getIndexedType()));
41 }
42 return true;
43 }
44 }