[clang] [llvm] [HLSL][SPIRV][DXIL] Implement `WaveActiveMax` intrinsic (PR #123428)

[Steven Perron via llvm-commits]

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@@ -0,0 +1,55 @@
+; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv-vulkan-unknown %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-vulkan-unknown %s -o - -filetype=obj | spirv-val %}
+
+; Test lowering to spir-v backend for various types and scalar/vector
+
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s-perron wrote:

Please check the capabilities as well:

```suggestion

; CHECK: OpCapability GroupNonUniformArithmetic 
```

https://github.com/llvm/llvm-project/pull/123428