[llvm] [Mips] Fix cttz.i32 fails to lower on mips16 (PR #179633)

[Matt Arsenault via llvm-commits]

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@@ -727,6 +727,9 @@ class LLVM_ABI TargetLoweringBase {
     return false;
   }
 
+  /// Return true if constant pool can be used for CTTZ expansion.
+  virtual bool canUseConstantPoolForCTTZ() const { return true; }
+
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arsenm wrote:

This doesn't make any sense and is too specific 

https://github.com/llvm/llvm-project/pull/179633