[llvm] [LLVM][InstCombine][SVE] Refactor sve.mul/fmul combines. (PR #134116)

[Paul Walker via llvm-commits]

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@@ -1112,6 +1112,19 @@ struct SVEIntrinsicInfo {
     return *this;
   }
 
+  bool hasMatchingIROpode() const { return IROpcode != 0; }
+
+  unsigned getMatchingIROpode() const {
+    assert(hasMatchingIROpode() && "Propery not set!");
+    return IROpcode;
+  }
+
+  SVEIntrinsicInfo &setMatchingIROpcode(unsigned Opcode) {
+    assert(!hasMatchingIROpode() && "Cannot set property twice!");
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paulwalker-arm wrote:

I consider that a bug.  The intent is for an intrinsic's `SVEIntrinsicInfo` to be constant and I have a hope to one day make this static rather than having to recompute it as is done today.

https://github.com/llvm/llvm-project/pull/134116