[PATCH] D39941: Set hasSideEffects=0 for TargetOpcode::{CFI_INSTRUCTION, EH_LABEL, GC_LABEL, ANNOTATION_LABEL}

[Reid Kleckner via Phabricator via llvm-commits]

rnk accepted this revision.
rnk added a comment.
This revision is now accepted and ready to land.

Looks good. I think MachineInstr::isPosition is a more accurate way to identify these types of label instructions. If there is any code that relies on hasUnmodeledSideEffects, we can update it to check isPosition instead.



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Comment at: include/llvm/Target/Target.td:933
   let hasCtrlDep = 1;
-  let hasSideEffects = 1;
+  let hasSideEffects = 0;
   let isNotDuplicable = 1;
----------------
Can you check this opcode in `MachineInstr::isLabel`? I think I forgot to do that when I added it. Otherwise, I worry that it `MachineInstr::isSafeToMove` will return true for ANNOTATION_LABEL after this change.


https://reviews.llvm.org/D39941