[clang] [llvm] [HLSL] Implement the `degrees` intrinsic (PR #111209)

[Greg Roth via cfe-commits]

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@@ -0,0 +1,54 @@
+; RUN: opt -S -dxil-intrinsic-expansion -scalarizer -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s | FileCheck %s
+
+; Make sure dxil op function calls for degrees are expanded and lowered as fmul for float and half.
+
+define noundef half @degrees_half(half noundef %a) {
+; CHECK-LABEL: define noundef half @degrees_half(
+; CHECK-SAME: half noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[DX_DEGREES1:%.*]] = fmul half [[A]], 0xH5329
+; CHECK-NEXT:    ret half [[DX_DEGREES1]]
+;
+entry:
+  %dx.degrees = call half @llvm.dx.degrees.f16(half %a)
+  ret half %dx.degrees
+}
+
+define noundef float @degrees_float(float noundef %a) #0 {
+; CHECK-LABEL: define noundef float @degrees_float(
+; CHECK-SAME: float noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[DX_DEGREES1:%.*]] = fmul float [[A]], 0x404CA5DC20000000
+; CHECK-NEXT:    ret float [[DX_DEGREES1]]
+;
+entry:
+  %dx.degrees = call float @llvm.dx.degrees.f32(float %a)
+  ret float %dx.degrees
+}
+
+define noundef <4 x float> @degrees_float4(<4 x float> noundef %a) #0 {
+; CHECK-LABEL: define noundef <4 x float> @degrees_float4(
+; CHECK-SAME: <4 x float> noundef [[A:%.*]]) {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[A_I0:%.*]] = extractelement <4 x float> [[A]], i64 0
+; CHECK-NEXT:    [[DOTI04:%.*]] = fmul float [[A_I0]], 0x404CA5DC20000000
+; CHECK-NEXT:    [[A_I1:%.*]] = extractelement <4 x float> [[A]], i64 1
+; CHECK-NEXT:    [[DOTI13:%.*]] = fmul float [[A_I1]], 0x404CA5DC20000000
+; CHECK-NEXT:    [[A_I2:%.*]] = extractelement <4 x float> [[A]], i64 2
+; CHECK-NEXT:    [[DOTI22:%.*]] = fmul float [[A_I2]], 0x404CA5DC20000000
+; CHECK-NEXT:    [[A_I3:%.*]] = extractelement <4 x float> [[A]], i64 3
+; CHECK-NEXT:    [[DOTI31:%.*]] = fmul float [[A_I3]], 0x404CA5DC20000000
+; CHECK-NEXT:    [[DOTUPTO0:%.*]] = insertelement <4 x float> poison, float [[DOTI04]], i64 0
+; CHECK-NEXT:    [[DOTUPTO1:%.*]] = insertelement <4 x float> [[DOTUPTO0]], float [[DOTI13]], i64 1
+; CHECK-NEXT:    [[DOTUPTO2:%.*]] = insertelement <4 x float> [[DOTUPTO1]], float [[DOTI22]], i64 2
+; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <4 x float> [[DOTUPTO2]], float [[DOTI31]], i64 3
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pow2clk wrote:

I don't know what any of these DOTI## variables refer to. It's not harmful, just confusing to read.

https://github.com/llvm/llvm-project/pull/111209