[llvm] [GlobalISel] Change MatchTable entries to 1 byte each (PR #74429)

[Pierre van Houtryve via llvm-commits]

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@@ -1354,8 +1385,8 @@ bool GIMatchTableExecutor::executeMatchTable(
     }
 
     case GIR_MakeTempReg: {
-      int64_t TempRegID = MatchTable[CurrentIdx++];
-      int64_t TypeID = MatchTable[CurrentIdx++];
+      uint64_t TempRegID = nextULEB128();
+      int64_t TypeID = (int8_t)MatchTable[CurrentIdx++];
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Pierre-vh wrote:

Indeed but it's needed, I've added a `readS8` wrapper around it with a comment explaining why we use that.


https://github.com/llvm/llvm-project/pull/74429