[llvm] [AMDGPU][TTI] Add Target Hook for Instruction Uniformity (getInstructionUniformity) (PR #137639)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,19 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -mtriple amdgcn-- -passes='print<uniformity>' -disable-output %s 2>&1 | FileCheck %s
+
+; CHECK: ALL VALUES UNIFORM
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arsenm wrote:

These aren't always always uniform, so need test coverage for all the conditions that would make this divergent 

https://github.com/llvm/llvm-project/pull/137639