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

[Kaitlin Peng via llvm-commits]

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@@ -34,10 +34,16 @@ def matrix_multiply_lowering
                         [{ return Helper.matchMatrixMultiply(*${root}); }]),
                     (apply [{ Helper.applyMatrixMultiply(*${root}); }])>;
 
+def degrees_lowering
+    : GICombineRule<(defs root:$root),
+                    (match (wip_match_opcode G_FMUL):$root,
+                        [{ return Helper.matchDegrees(*${root}); }]),
+                    (apply [{ Helper.applyDegrees(*${root}); }])>;
+
 def SPIRVPreLegalizerCombiner
     : GICombiner<"SPIRVPreLegalizerCombinerImpl",
                  [vector_length_sub_to_distance_lowering,
                   vector_select_to_faceforward_lowering,
-                  matrix_transpose_lowering, matrix_multiply_lowering]> {
+                  matrix_transpose_lowering, matrix_multiply_lowering, degrees_lowering]> {
   let CombineAllMethodName = "tryCombineAllImpl";
-}
+}
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kmpeng wrote:

Revert this?

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