[llvm] [GlobalIsel] Combine select of binops (PR #76763)

[Amara Emerson via llvm-commits]

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@@ -558,6 +558,109 @@ class GVecReduce : public GenericMachineInstr {
   }
 };
 
+// Represents a binary operation, i.e, x = y op z.
+class GBinOp : public GenericMachineInstr {
+public:
+  Register getLHSReg() const { return getReg(1); }
+  Register getRHSReg() const { return getReg(2); }
+
+  static bool classof(const MachineInstr *MI) {
+    switch (MI->getOpcode()) {
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aemerson wrote:

I was going to suggest that too but it won't compile due to not yet seeing the definition of `GIntBinOp` when parsing this class.

https://github.com/llvm/llvm-project/pull/76763