[clang] [llvm] Add step builtins and step HLSL function to DirectX and SPIR-V backend (PR #106471)

[Justin Bogner via cfe-commits]

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@@ -0,0 +1,79 @@
+; RUN: opt -S  -dxil-intrinsic-expansion  < %s | FileCheck %s --check-prefix=CHECK
+; RUN: opt -S  -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library < %s | FileCheck %s --check-prefix=CHECK
+
+; Make sure dxil operation function calls for step are generated for half/float.
+
+declare half @llvm.dx.step.f16(half, half)
+declare <2 x half> @llvm.dx.step.v2f16(<2 x half>, <2 x half>)
+declare <3 x half> @llvm.dx.step.v3f16(<3 x half>, <3 x half>)
+declare <4 x half> @llvm.dx.step.v4f16(<4 x half>, <4 x half>)
+
+declare float @llvm.dx.step.f32(float, float)
+declare <2 x float> @llvm.dx.step.v2f32(<2 x float>, <2 x float>)
+declare <3 x float> @llvm.dx.step.v3f32(<3 x float>, <3 x float>)
+declare <4 x float> @llvm.dx.step.v4f32(<4 x float>, <4 x float>)
+
+define noundef half @test_step_half(half noundef %p0, half noundef %p1) {
+entry:
+  ; CHECK: %0 = fcmp olt half %p1, %p0
+  ; CHECK: %1 = select i1 %0, half 0xH0000, half 0xH3C00
+  ; DOPCHECK: asdahg
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bogner wrote:

Typo / something left over from debugging?

https://github.com/llvm/llvm-project/pull/106471