[llvm] Add PreLegalizer pattern matching for degrees GL extension (PR #216506)

[Kaitlin Peng via llvm-commits]

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@@ -45,6 +45,24 @@ entry:
   ret <4 x half> %elt.degrees
 }
 
+; CHECK-LABEL: Begin function fmul_to_degrees
+define noundef float @fmul_to_degrees(float noundef %x) {
+entry:
+; CHECK: %[[#arg:]] = OpFunctionParameter %[[#float_32]]
+; CHECK: %[[#]] = OpExtInst %[[#float_32]] %[[#op_ext_glsl]] Degrees %[[#arg]]
+  %mul = fmul reassoc nnan ninf nsz arcp afn float %x, f0x42652EE1
+  ret float %mul
+}
+
+; CHECK-LABEL: Begin function fmul_to_degrees_vector
+define hidden noundef nofpclass(nan inf) <4 x float> @fmul_to_degrees_vector(<4 x float> noundef nofpclass(nan inf) %v) local_unnamed_addr #0 {
+entry:
+; CHECK: %[[#arg:]] = OpFunctionParameter %[[#vec4_float_32]]
+; CHECK: %[[#]] = OpExtInst %[[#vec4_float_32]] %[[#op_ext_glsl]] Degrees %[[#arg]]
+  %mul.i = fmul reassoc nnan ninf nsz arcp afn <4 x float> %v, splat (float f0x42652EE1)
+  ret <4 x float> %mul.i
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kmpeng wrote:

I don't see a change for this? Either way it's fine if you don't want to change it, just a nit.

https://github.com/llvm/llvm-project/pull/216506