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llvm-svn: 142592
This commit is contained in:
Devang Patel 2011-10-20 17:31:18 +00:00
parent 547dde4517
commit 82af5e0ece

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@ -788,7 +788,9 @@ bool MachineLICM::IsLICMCandidate(MachineInstr &I) {
// If it is load then check if it is guaranteed to execute by making sure that
// it dominates all exiting blocks. If it doesn't, then there is a path out of
// the loop which does not execute this load, so we can't hoist it.
// the loop which does not execute this load, so we can't hoist it. Loads
// from constant memory are not safe to speculate all the time, for example
// indexed load from a jump table.
// Stores and side effects are already checked by isSafeToMove.
if (I.getDesc().mayLoad() && !isLoadFromGOT(I) &&
!IsGuaranteedToExecute(I.getParent()))