[clang][Interp] Implement __builtin_classify_type (#71972)

This adds some infrastructure for unevaluated builtin calls, and uses the implementation from ExprConstant.cpp

1 files changed, 3 insertions, 35 deletions

diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 4fb444e..3a41e97 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -32,6 +32,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "ExprConstShared.h"
 #include "Interp/Context.h"
 #include "Interp/Frame.h"
 #include "Interp/State.h"
@@ -11492,43 +11493,10 @@ bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
   return false;
 }
 
-/// Values returned by __builtin_classify_type, chosen to match the values
-/// produced by GCC's builtin.
-enum class GCCTypeClass {
-  None = -1,
-  Void = 0,
-  Integer = 1,
-  // GCC reserves 2 for character types, but instead classifies them as
-  // integers.
-  Enum = 3,
-  Bool = 4,
-  Pointer = 5,
-  // GCC reserves 6 for references, but appears to never use it (because
-  // expressions never have reference type, presumably).
-  PointerToDataMember = 7,
-  RealFloat = 8,
-  Complex = 9,
-  // GCC reserves 10 for functions, but does not use it since GCC version 6 due
-  // to decay to pointer. (Prior to version 6 it was only used in C++ mode).
-  // GCC claims to reserve 11 for pointers to member functions, but *actually*
-  // uses 12 for that purpose, same as for a class or struct. Maybe it
-  // internally implements a pointer to member as a struct?  Who knows.
-  PointerToMemberFunction = 12, // Not a bug, see above.
-  ClassOrStruct = 12,
-  Union = 13,
-  // GCC reserves 14 for arrays, but does not use it since GCC version 6 due to
-  // decay to pointer. (Prior to version 6 it was only used in C++ mode).
-  // GCC reserves 15 for strings, but actually uses 5 (pointer) for string
-  // literals.
-  // Lang = 16,
-  // OpaqueType = 17,
-  BitInt = 18
-};
-
 /// EvaluateBuiltinClassifyType - Evaluate __builtin_classify_type the same way
 /// as GCC.
-static GCCTypeClass
-EvaluateBuiltinClassifyType(QualType T, const LangOptions &LangOpts) {
+GCCTypeClass EvaluateBuiltinClassifyType(QualType T,
+                                         const LangOptions &LangOpts) {
   assert(!T->isDependentType() && "unexpected dependent type");
 
   QualType CanTy = T.getCanonicalType();