[PATCH] D129690: [LLVM][AMDGPU] Specialize 32-bit atomic fadd instruction for generic address space

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/SIISelLowering.cpp:12734
         if (Ty->isFloatTy() && AS == AMDGPUAS::FLAT_ADDRESS)
-          return AtomicExpansionKind::CmpXChg;
+          return AtomicExpansionKind::Expand;
 
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If this atomic falls into system scope it has to be expanded into CAS. This code breaks the logic.
The check below was done after the AS check to perform a fast check first since the outcome is the same anyway. This is not true anymore.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D129690/new/

https://reviews.llvm.org/D129690