[PATCH] D95540: [AMDGPU][GlobalISel] Remove redundant cmp when copying constant to vcc

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp:145
+        BuildMI(*BB, &I, DL, TII.get(MovOpc), DstReg)
+            .addImm(ConstVal->Value.getBoolValue() ? -1 : 0);
+      } else {
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foad wrote:
> Is it really correct to use -1 here if the condition is true? Shouldn't it be "s_mov dst, exec(_lo)" instead?
I think it's an open question if an s1 value means a boolean anded with the correct exec mask. My current thinking is the answer is no and the uses that care are responsible for masking out exec bits


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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D95540/new/

https://reviews.llvm.org/D95540