[llvm] [AMDGPU] Produce ballot/icmp/fcmp lane masks at wavefront width (PR #201358)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,65 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=amdgcn -global-isel=0 -mcpu=gfx900 < %s | FileCheck %s
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arsenm wrote:

-global-isel=0 should only be used when testing both selectors 

https://github.com/llvm/llvm-project/pull/201358