[PATCH] D64757: [PEI] Don't re-allocate a pre-allocated stack protector slot

[Eli Friedman via Phabricator via llvm-commits]

efriedma added inline comments.


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Comment at: llvm/lib/CodeGen/LocalStackSlotAllocation.cpp:202
   SmallSet<int, 16> ProtectedObjs;
-  if (MFI.getStackProtectorIndex() >= 0) {
+  if (MFI.hasStackProtectorIndex()) {
+    int StackProtectorFI = MFI.getStackProtectorIndex();
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Is this change a no-op?


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Comment at: llvm/lib/CodeGen/PrologEpilogInserter.cpp:932
+  // LocalStackSlotPass didn't already allocate a slot for it. If it did, we
+  // need to use that one.
+  if (MFI.hasStackProtectorIndex() &&
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We obviously don't want to re-allocate a slot for the stack protector, but what about the other stack objects?  Do we guarantee that LocalStackSlotPass will allocate all obejcts where getObjectSSPLayout() is not SSPLK_None?  If we do, we can just simplify this check to `if (MFI.getUseLocalStackAllocationBlock())`.  Otherwise, we should still run this code for all the all the non-stack-protector frame indexes.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D64757/new/

https://reviews.llvm.org/D64757