[PATCH] D54882: [AMDGPU] Add sdwa support for ADD|SUB U64 decomposed Pseudos

[Stanislav Mekhanoshin via Phabricator via llvm-commits]

rampitec added inline comments.


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Comment at: lib/Target/AMDGPU/SIPeepholeSDWA.cpp:911
+  auto Liveness = MBB.computeRegisterLiveness(TRI, AMDGPU::VCC, MI, 25);
+  if (Liveness != MachineBasicBlock::LQR_Dead)
+    return;
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rampitec wrote:
> That is not sufficient. You have checked that VCC is dead and the MI, fine. Now you need to check that it is not defined anywhere between MI and MISucc.
And write tests for it of course: non-dead vcc, vcc def in between of two and vcc_lo (partial) def.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D54882/new/

https://reviews.llvm.org/D54882