[llvm] [TableGen][DecoderEmitter] Add OPC_Scope opcode (PR #155580)

[Sergei Barannikov via llvm-commits]

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@@ -308,21 +306,17 @@ class DecoderTable {
 
 struct DecoderTableInfo {
   DecoderTable Table;
-  FixupScopeList FixupStack;
+  SmallVector<unsigned, 8> FixupStack;
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s-barannikov wrote:

Since we can only have one fixup location (for the innermost OPC_Scope), we no longer need vector of vectors.

https://github.com/llvm/llvm-project/pull/155580