[llvm] [SelectionDAG] Add space-optimized forms of OPC_CheckComplexPat (PR #73310)

[Matt Arsenault via llvm-commits]

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@@ -56,7 +56,7 @@ static MVT::SimpleValueType getRegisterValueType(Record *R,
 namespace {
   class MatcherGen {
     const PatternToMatch &Pattern;
-    const CodeGenDAGPatterns &CGP;
+    CodeGenDAGPatterns &CGP;
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arsenm wrote:

Seems unfortunate to lose const for this 

https://github.com/llvm/llvm-project/pull/73310