[llvm] [AMDGPU] NFC. Add opt instcombine pass for llvm.amdgcn.ballot.i64.wave32.ll test. (PR #73779)

[Matt Arsenault via llvm-commits]

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@@ -3,6 +3,10 @@
 ; RUN: llc -march=amdgcn -global-isel=0 -mcpu=gfx1100 -amdgpu-enable-delay-alu=0 < %s | FileCheck %s --check-prefixes=CHECK,DAGISEL
 ; RUN: llc -march=amdgcn -global-isel -mcpu=gfx1010 < %s | FileCheck %s --check-prefixes=CHECK,GISEL
 ; RUN: llc -march=amdgcn -global-isel -mcpu=gfx1100 -amdgpu-enable-delay-alu=0 < %s | FileCheck %s --check-prefixes=CHECK,GISEL
+; RUN: opt -mtriple=amdgcn-- -mcpu=gfx1010 -mattr=+wavefrontsize32,-wavefrontsize64 -passes=instcombine -o - < %s | llc -march=amdgcn -global-isel=0 -mcpu=gfx1010 - | FileCheck %s --check-prefixes=CHECK-OPT,DAGISEL-OPT
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arsenm wrote:

They're really 2 separately testable pieces, and this doesn't show you the entire compilation output (especially the -O0 bit). We don't really have anywhere that does end to end pipeline tests, but clang has a few. 

https://github.com/llvm/llvm-project/pull/73779