[clang] [llvm] [HLSL] Implement `WaveReadLaneAt` intrinsic (PR #111010)

[Chris B via cfe-commits]

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@@ -87,6 +87,7 @@ class CGHLSLRuntime {
   GENERATE_HLSL_INTRINSIC_FUNCTION(SDot, sdot)
   GENERATE_HLSL_INTRINSIC_FUNCTION(UDot, udot)
   GENERATE_HLSL_INTRINSIC_FUNCTION(WaveIsFirstLane, wave_is_first_lane)
+  GENERATE_HLSL_INTRINSIC_FUNCTION(WaveReadLaneAt, waveReadLaneAt)
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llvm-beanz wrote:

This isn't just a convention for our backend, this is a convention common across LLVM backends. For example look at the AMD GCN intrinsics like `llvm.amdgcn.raw.ptr.buffer.store`.

I can see an argument that the `_`s were placed in the wrong places, but I think this was the wrong decision. A better name might be `wave_readlaneat`, but `camelCase` isn't really used in intrinsic names.

@bogner & @farzonl, we should discuss this before we break with common LLVM convention.

https://github.com/llvm/llvm-project/pull/111010