[PATCH] D96980: [amdgpu] Revert agnostic SGPR spill.

[Carl Ritson via Phabricator via llvm-commits]

critson added a comment.

In D96980#2579955 <https://reviews.llvm.org/D96980#2579955>, @hliao wrote:

> Mark SI_SPILL_<n>_RESTORE having unwanted effect so that they would be executed under exec mask 0.

I assume you mean "[...] so they would **not** be executed under exec mask 0"?



================
Comment at: llvm/lib/Target/AMDGPU/SIInstrInfo.cpp:3316
+  }
+
   return false;
----------------
This seems reasonable.
It avoids the case where an EXEC=0 region attempts to restore an SGPR for immediate use in the same region.
I guess we are assuring ourselves that semantically an EXEC=0 region never restores an SGPR expecting it to be live beyond that region?
(And that EXEC=0 regions will never save SGPRs expecting them to have meaningful effects elsewhere.)


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https://reviews.llvm.org/D96980