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| author | Devang Patel <dpatel@apple.com> | 2011-10-20 17:31:18 +0000 |
|---|---|---|
| committer | Devang Patel <dpatel@apple.com> | 2011-10-20 17:31:18 +0000 |
| commit | 830c776a94eb18273c1bd6cf03fb997dd91e5c3e (patch) | |
| tree | a23962afca8acbaab38cdc0b28d21ef1d6e1ddab /llvm/lib/CodeGen/MachineLICM.cpp | |
| parent | 79ebc51c4569c07cf92d9c64b75fc7d0a592195f (diff) | |
| download | bcm5719-llvm-830c776a94eb18273c1bd6cf03fb997dd91e5c3e.tar.gz bcm5719-llvm-830c776a94eb18273c1bd6cf03fb997dd91e5c3e.zip | |
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llvm-svn: 142592
Diffstat (limited to 'llvm/lib/CodeGen/MachineLICM.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineLICM.cpp | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/MachineLICM.cpp b/llvm/lib/CodeGen/MachineLICM.cpp index 969a9b084d5..c693386f9bb 100644 --- a/llvm/lib/CodeGen/MachineLICM.cpp +++ b/llvm/lib/CodeGen/MachineLICM.cpp @@ -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())) |
