[PATCH] D140417: [SelectionDAG] Fix EmitCopyFromReg for cloned nodes

Tue Dec 20 10:00:22 PST 2022

arsenm added inline comments.

================
Comment at: llvm/test/CodeGen/AMDGPU/bug-sdag-emitcopyfromreg.ll:1
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
 ; RUN: llc -march=amdgcn -mcpu=gfx1010 < %s | FileCheck %s
----------------
foad wrote:
> I am struggling to come up with a good test case. This one doesn't really demonstrate the problem. Immediately after isel there is a problem, because an S_AND_B32 instruction clobbers $scc when it should not. But then after isel the S_AND_B32 gets converted to V_AND_B32, so the problem goes away.
> 
> I could change the test to dump MIR with -stop-before=si-fix-sgpr-copies if that's acceptable.
I think having both IR and MIR tests would be good here. -stop-before=si-fix-sgpr-copies is the right way to test a lot of these things

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D140417/new/

https://reviews.llvm.org/D140417