[llvm] [TLI] Add getLibFunc that accepts an Opcode and scalar Type. (PR #75919)

[Paul Walker via llvm-commits]

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@@ -156,6 +156,10 @@ class TargetLibraryInfoImpl {
   /// FDecl is assumed to have a parent Module when using this function.
   bool getLibFunc(const Function &FDecl, LibFunc &F) const;
 
+  /// Searches for a function name using an Instruction \p Opcode.
+  /// Currently, only the frem instruction is supported.
+  bool getLibFunc(unsigned int Opcode, Type *ScalarTy, LibFunc &F) const;
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paulwalker-arm wrote:

I'd just use `Ty` instead of `ScalarTy` because the interface doesn't care what the type is.

https://github.com/llvm/llvm-project/pull/75919