[llvm] [MC][TableGen] Expand Opcode field of MCInstrDesc (PR #179652)

[Fangrui Song via llvm-commits]

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@@ -203,7 +203,7 @@ class MCInstrDesc {
   // the <Target>Insts table because they rely on knowing their own address to
   // find other information elsewhere in the same table.
 
-  unsigned short Opcode;         // The opcode number
+  unsigned int Opcode;           // The opcode number
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MaskRay wrote:

`unsigned `int` => `unsigned`

https://github.com/llvm/llvm-project/pull/179652