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

[Finn Plummer via cfe-commits]

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@@ -428,6 +431,7 @@ bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
 
   case TargetOpcode::G_INTRINSIC:
   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
+  case TargetOpcode::G_INTRINSIC_CONVERGENT:
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inbelic wrote:

Afaict, not within this section of the codebase, it is used elsewhere though eg `GlobalISel`. But I think @Keenuts would be able to better elaborate.

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