Instcombine this away:

%A = getelementptr [4 x int]* %M, long 0, long 0
        %B = getelementptr int* %A, long 2


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4536 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2002-11-04 16:43:32 +00:00
parent a3c4ba427b
commit 0188534cd1

View File

@ -681,11 +681,17 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
*cast<Constant>(GEP.getOperand(1));
assert(Indices[0] != 0 && "Constant folding of uint's failed!?");
} else if (*GEP.idx_begin() == ConstantUInt::getNullValue(Type::LongTy) &&
} else if (*GEP.idx_begin() == Constant::getNullValue(Type::LongTy) &&
Src->getNumOperands() != 1) {
// Otherwise we can do the fold if the first index of the GEP is a zero
Indices.insert(Indices.end(), Src->idx_begin(), Src->idx_end());
Indices.insert(Indices.end(), GEP.idx_begin()+1, GEP.idx_end());
} else if (Src->getOperand(Src->getNumOperands()-1) ==
Constant::getNullValue(Type::LongTy)) {
// If the src gep ends with a constant array index, merge this get into
// it, even if we have a non-zero array index.
Indices.insert(Indices.end(), Src->idx_begin(), Src->idx_end()-1);
Indices.insert(Indices.end(), GEP.idx_begin(), GEP.idx_end());
}
if (!Indices.empty())