[clang][bytecode][NFC] Remove unused function (llvm#139355)

Author: tbaederr

clang/lib/AST/ByteCode/Interp.cpp

@@ -942,15 +942,6 @@ bool CheckThis(InterpState &S, CodePtr OpPC, const Pointer &This) {
   return false;
 }
 
-bool CheckPure(InterpState &S, CodePtr OpPC, const CXXMethodDecl *MD) {
-  if (!MD->isPureVirtual())
-    return true;
-  const SourceInfo &E = S.Current->getSource(OpPC);
-  S.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << MD;
-  S.Note(MD->getLocation(), diag::note_declared_at);
-  return false;
-}
-
 bool CheckFloatResult(InterpState &S, CodePtr OpPC, const Floating &Result,
                       APFloat::opStatus Status, FPOptions FPO) {
   // [expr.pre]p4:

clang/lib/AST/ByteCode/Interp.h

@@ -114,9 +114,6 @@ bool CheckCallDepth(InterpState &S, CodePtr OpPC);
 /// Checks the 'this' pointer.
 bool CheckThis(InterpState &S, CodePtr OpPC, const Pointer &This);
 
-/// Checks if a method is pure virtual.
-bool CheckPure(InterpState &S, CodePtr OpPC, const CXXMethodDecl *MD);
-
 /// Checks if all the arguments annotated as 'nonnull' are in fact not null.
 bool CheckNonNullArgs(InterpState &S, CodePtr OpPC, const Function *F,
                       const CallExpr *CE, unsigned ArgSize);