[llvm] [GlobalIsel] Combine G_VSCALE (PR #94096)

[Matt Arsenault via llvm-commits]

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@@ -856,6 +858,43 @@ class GTrunc : public GCastOp {
   };
 };
 
+/// Represents a vscale.
+class GVScale : public GenericMachineInstr {
+public:
+  APInt getSrc() const { return getOperand(1).getCImm()->getValue(); }
+
+  static bool classof(const MachineInstr *MI) {
+    return MI->getOpcode() == TargetOpcode::G_VSCALE;
+  };
+};
+
+/// Represents an integer subtraction.
+class GSub : public GIntBinOp {
+public:
+  static bool classof(const MachineInstr *MI) {
+    return MI->getOpcode() == TargetOpcode::G_SUB;
+  };
+};
+
+/// Represents an integer multiplication.
+class GMul : public GIntBinOp {
+public:
+  static bool classof(const MachineInstr *MI) {
+    return MI->getOpcode() == TargetOpcode::G_MUL;
+  };
+};
+
+/// Represents a shift left.
+class GSHL : public GenericMachineInstr {
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arsenm wrote:

Inconsistent capitalization with other ops, GShl? 

https://github.com/llvm/llvm-project/pull/94096