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

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,56 @@
+; RUN: opt -S -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-compute %s | FileCheck %s
+
+; Test that for scalar values, WaveReadLaneAt maps down to the DirectX op
+
+define noundef half @wave_rla_half(half noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call half @dx.op.waveReadLaneAt.f16(i32 117, half %expr, i32 %idx)
+  %ret = call half @llvm.dx.wave.read.lane.at.f16(half %expr, i32 %idx)
+  ret half %ret
+}
+
+define noundef float @wave_rla_float(float noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call float @dx.op.waveReadLaneAt.f32(i32 117, float %expr, i32 %idx)
+  %ret = call float @llvm.dx.wave.read.lane.at(float %expr, i32 %idx)
+  ret float %ret
+}
+
+define noundef double @wave_rla_double(double noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call double @dx.op.waveReadLaneAt.f64(i32 117, double %expr, i32 %idx)
+  %ret = call double @llvm.dx.wave.read.lane.at(double %expr, i32 %idx)
+  ret double %ret
+}
+
+define noundef i1 @wave_rla_i1(i1 noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call i1 @dx.op.waveReadLaneAt.i1(i32 117, i1 %expr, i32 %idx)
+  %ret = call i1 @llvm.dx.wave.read.lane.at.i1(i1 %expr, i32 %idx)
+  ret i1 %ret
+}
+
+define noundef i16 @wave_rla_i16(i16 noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call i16 @dx.op.waveReadLaneAt.i16(i32 117, i16 %expr, i32 %idx)
+  %ret = call i16 @llvm.dx.wave.read.lane.at.i16(i16 %expr, i32 %idx)
+  ret i16 %ret
+}
+
+define noundef i32 @wave_rla_i32(i32 noundef %expr, i32 noundef %idx) #0 {
+entry:
+; CHECK: call i32 @dx.op.waveReadLaneAt.i32(i32 117, i32 %expr, i32 %idx)
+  %ret = call i32 @llvm.dx.wave.read.lane.at.i32(i32 %expr, i32 %idx)
+  ret i32 %ret
+}
+
+declare half @llvm.dx.wave.read.lane.at.f16(half, i32) #1
+declare float @llvm.dx.wave.read.lane.at.f32(float, i32) #1
+declare double @llvm.dx.wave.read.lane.at.f64(double, i32) #1
+
+declare i1 @llvm.dx.wave.read.lane.at.i1(i1, i32) #1
+declare i16 @llvm.dx.wave.read.lane.at.i16(i16, i32) #1
+declare i32 @llvm.dx.wave.read.lane.at.i32(i32, i32) #1
+
+attributes #0 = { norecurse "hlsl.numthreads"="1,1,1" "hlsl.shader"="compute" "no-trapping-math"="true" "stack-protector-buffer-size"="8" }
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farzonl wrote:

delete the attributes. line 55 and 56

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