[llvm] [AMDGPU] Add an SCC def to the wave.reduce pseudos (PR #228723)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,66 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgpu9.00 -global-isel=0 < %s | FileCheck %s
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arsenm wrote:

Only use -global-isel=0 if testing both selectors

https://github.com/llvm/llvm-project/pull/228723