[llvm] s390x: pattern match saturated truncation (PR #155377)

[Folkert de Vries via llvm-commits]

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@@ -680,39 +696,39 @@ let Predicates = [FeatureVector] in {
   let isCommutable = 1 in {
     // Maximum.
     def VMX  : BinaryVRRcGeneric<"vmx", 0xE7FF>;
-    def VMXB : BinaryVRRc<"vmxb", 0xE7FF, null_frag, v128b, v128b, 0>;
-    def VMXH : BinaryVRRc<"vmxh", 0xE7FF, null_frag, v128h, v128h, 1>;
-    def VMXF : BinaryVRRc<"vmxf", 0xE7FF, null_frag, v128f, v128f, 2>;
-    def VMXG : BinaryVRRc<"vmxg", 0xE7FF, null_frag, v128g, v128g, 3>;
+    def VMXB : BinaryVRRc<"vmxb", 0xE7FF, smax, v128b, v128b, 0>;
+    def VMXH : BinaryVRRc<"vmxh", 0xE7FF, smax, v128h, v128h, 1>;
+    def VMXF : BinaryVRRc<"vmxf", 0xE7FF, smax, v128f, v128f, 2>;
+    def VMXG : BinaryVRRc<"vmxg", 0xE7FF, smax, v128g, v128g, 3>;
     let Predicates = [FeatureVectorEnhancements3] in
       def VMXQ : BinaryVRRc<"vmxq", 0xE7FF, null_frag, v128q, v128q, 4>;
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folkertdev wrote:

Done, it causes some trivial register renames in the tests, but otherwise seems to work ok.

https://github.com/llvm/llvm-project/pull/155377