ADd a trivial instcombine: load null -> null

llvm-svn: 12940
This commit is contained in:
Chris Lattner 2004-04-14 03:28:36 +00:00
parent 0dc099c2b5
commit 6679e46b59
1 changed files with 5 additions and 2 deletions

View File

@ -2853,7 +2853,10 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) {
Value *Op = LI.getOperand(0);
if (LI.isVolatile()) return 0;
if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Op))
if (Constant *C = dyn_cast<Constant>(Op))
if (C->isNullValue()) // load null -> 0
return ReplaceInstUsesWith(LI, Constant::getNullValue(LI.getType()));
else if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C))
Op = CPR->getValue();
// Instcombine load (constant global) into the value loaded...