Add some comments here because the lack of a check for volatile/atomic here is a bit unusual.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137662 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Eli Friedman 2011-08-15 21:56:39 +00:00
parent 50b37c7920
commit c869b4397a

View File

@ -188,12 +188,16 @@ Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
--ScanFrom;
// If this is a load of Ptr, the loaded value is available.
// (This is true even if the load is volatile or atomic, although
// those cases are unlikely.)
if (LoadInst *LI = dyn_cast<LoadInst>(Inst))
if (AreEquivalentAddressValues(LI->getOperand(0), Ptr))
return LI;
if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
// If this is a store through Ptr, the value is available!
// (This is true even if the store is volatile or atomic, although
// those cases are unlikely.)
if (AreEquivalentAddressValues(SI->getOperand(1), Ptr))
return SI->getOperand(0);