[llvm] [SelectionDAG] Add space-optimized forms of OPC_CheckPredicate (PR #77763)

[Fangrui Song via llvm-commits]

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@@ -88,6 +87,8 @@ class MatcherTableEmitter {
     DenseMap<const ComplexPattern *, unsigned> ComplexPatternUsage;
     // Record the usage of PatternPredicate.
     std::map<StringRef, unsigned> PatternPredicateUsage;
+    // Record the usage of Predicate.
+    DenseMap<TreePattern *, unsigned> PredicateUsage;
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MaskRay wrote:

This should use `MapVector`.  I've fixed `ComplexPatternUsage` in c230138011cbf07ad7caf9d256ae9d0c5032a974

https://github.com/llvm/llvm-project/pull/77763