Generate much more efficient code in programs like pifft

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11775 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2004-02-23 21:46:58 +00:00
parent 077a373791
commit d8864ce766

View File

@ -2163,6 +2163,14 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
// Replace: gep (gep %P, long B), long A, ...
// With: T = long A+B; gep %P, T, ...
//
// Note that if our source is a gep chain itself that we wait for that
// chain to be resolved before we perform this transformation. This
// avoids us creating a TON of code in some cases.
//
if (isa<GetElementPtrInst>(Src->getOperand(0)) &&
cast<Instruction>(Src->getOperand(0))->getNumOperands() == 2)
return 0; // Wait until our source is folded to completion.
Value *Sum = BinaryOperator::create(Instruction::Add, Src->getOperand(1),
GEP.getOperand(1),
Src->getName()+".sum", &GEP);