[llvm] [WIP][RFC] Teach MCA constant registers do not create dependencies (PR #89387)

[Rin Dobrescu via llvm-commits]

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@@ -962,7 +962,7 @@ void RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
 
   OS << "extern const MCRegisterDesc " << TargetName
      << "RegDesc[] = { // Descriptors\n";
-  OS << "  { " << RegStrings.get("") << ", 0, 0, 0, 0, 0 },\n";
+  OS << "  { " << RegStrings.get("") << ", 0, 0, 0, 0, 0, 0 },\n";
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Rin18 wrote:

I'm not entirely sure what the purpose of this line is. Since it's printed before register descriptors are emitted, my assumption is that it's displaying the general layout of the MCRegisterDesc struct. As I am changing MCRegisterDesc to hold 7 instead of 6 elements, this change seemed relevant in order to keep the structure consistent.

https://github.com/llvm/llvm-project/pull/89387