[llvm] [WebAssembly] [Codegen] Add pattern for relaxed min max from pmin/pmax-based patterns over v4f32 and v2f64 (PR #164486)

[Sam Parker via llvm-commits]

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@@ -1692,6 +1692,42 @@ defm SIMD_RELAXED_FMIN :
 defm SIMD_RELAXED_FMAX :
    RelaxedBinary<F64x2, int_wasm_relaxed_max, "relaxed_max", 0x110>;
 
+let Predicates = [HasRelaxedSIMD] in {
+  foreach vec = [F32x4, F64x2] in {
+    defvar relaxed_min = !cast<NI>("SIMD_RELAXED_FMIN_"#vec);
+    defvar relaxed_max = !cast<NI>("SIMD_RELAXED_FMAX_"#vec);
+
+    // Transform standard fminimum/fmaximum to relaxed versions
+    def : Pat<(vec.vt (fminnum (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+              (relaxed_min V128:$lhs, V128:$rhs)>;
+    def : Pat<(vec.vt (fminimumnum (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+              (relaxed_min V128:$lhs, V128:$rhs)>;
+    def : Pat<(vec.vt (fmaxnum (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+              (relaxed_max V128:$lhs, V128:$rhs)>;
+    def : Pat<(vec.vt (fmaximumnum (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+              (relaxed_max V128:$lhs, V128:$rhs)>;
+
+    // Transform pmin/max-supposed patterns to relaxed min max
+    let AddedComplexity = 1 in {
+      def : Pat<(vec.vt (pmin (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+                (relaxed_min $lhs, $rhs)>;
+      def : Pat<(vec.vt (pmax (vec.vt V128:$lhs), (vec.vt V128:$rhs))),
+                (relaxed_max $lhs, $rhs)>;
+
+      def : Pat<(vec.int_vt (vselect
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sparker-arm wrote:

I know this is how the original patterns are defined, but is there a way that we can fold this fragments into the definition of pmin/max? It just seems a bit cumbersome to have to duplicate it.

https://github.com/llvm/llvm-project/pull/164486