[llvm] [AMDGPU][AsmParser] Simplify getting source locations of operands. (PR #158323)

[Stanislav Mekhanoshin via llvm-commits]

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@@ -228,6 +213,9 @@ class AMDGPUOperand : public MCParsedAsmOperand {
     const MCExpr *Expr;
   };
 
+  // The index of the associated MCInst operand.
+  mutable int MCOpIdx = -1;
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rampitec wrote:

Can mutable be avoided?

https://github.com/llvm/llvm-project/pull/158323