[clang] [llvm] [NFC] Replace more DenseMaps with SmallDenseMaps (PR #111836)

[Nikita Popov via cfe-commits]

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@@ -51,7 +51,7 @@ class ConstraintSystem {
 
   /// A map of variables (IR values) to their corresponding index in the
   /// constraint system.
-  DenseMap<Value *, unsigned> Value2Index;
+  SmallDenseMap<Value *, unsigned, 16> Value2Index;
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nikic wrote:

I'd add a using/typedef for this one, especially as it needs to be synchronized with ConstraintElimination.

https://github.com/llvm/llvm-project/pull/111836