[clang] [llvm] [AMDGPU] Match bitsin(typeof(x)) - popcnt(x) to s_bcnt0_i32 (PR #164847)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,110 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn -mcpu=gfx900 < %s | FileCheck %s
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arsenm wrote:

This is failing on the broken v-to-s copy for the asm input. I think this is the global isel flavored version of the case the DAG path miscompiles into ignoring the SGPR constraint 

https://github.com/llvm/llvm-project/pull/164847