[Clang] Add BuiltinTemplates.td to generate code for builtin templates

clang/include/clang/AST/ASTContext.h

@@ -410,14 +410,8 @@ class ASTContext : public RefCountedBase<ASTContext> {
   /// The identifier 'NSCopying'.
   IdentifierInfo *NSCopyingName = nullptr;
 
-  /// The identifier '__make_integer_seq'.
-  mutable IdentifierInfo *MakeIntegerSeqName = nullptr;
-
-  /// The identifier '__type_pack_element'.
-  mutable IdentifierInfo *TypePackElementName = nullptr;
-
-  /// The identifier '__builtin_common_type'.
-  mutable IdentifierInfo *BuiltinCommonTypeName = nullptr;
+#define BuiltinTemplate(BTName) mutable IdentifierInfo *Name##BTName = nullptr;
+#include "clang/Basic/BuiltinTemplates.inc"
 
   QualType ObjCConstantStringType;
   mutable RecordDecl *CFConstantStringTagDecl = nullptr;
@@ -629,9 +623,10 @@ class ASTContext : public RefCountedBase<ASTContext> {
 
   TranslationUnitDecl *TUDecl = nullptr;
   mutable ExternCContextDecl *ExternCContext = nullptr;
-  mutable BuiltinTemplateDecl *MakeIntegerSeqDecl = nullptr;
-  mutable BuiltinTemplateDecl *TypePackElementDecl = nullptr;
-  mutable BuiltinTemplateDecl *BuiltinCommonTypeDecl = nullptr;
+
+#define BuiltinTemplate(BTName)                                                \
+  mutable BuiltinTemplateDecl *Decl##BTName = nullptr;
+#include "clang/Basic/BuiltinTemplates.inc"
 
   /// The associated SourceManager object.
   SourceManager &SourceMgr;
@@ -1157,9 +1152,9 @@ class ASTContext : public RefCountedBase<ASTContext> {
   }
 
   ExternCContextDecl *getExternCContextDecl() const;
-  BuiltinTemplateDecl *getMakeIntegerSeqDecl() const;
-  BuiltinTemplateDecl *getTypePackElementDecl() const;
-  BuiltinTemplateDecl *getBuiltinCommonTypeDecl() const;
+
+#define BuiltinTemplate(BTName) BuiltinTemplateDecl *get##BTName##Decl() const;
+#include "clang/Basic/BuiltinTemplates.inc"
 
   // Builtin Types.
   CanQualType VoidTy;
@@ -2107,23 +2102,13 @@ class ASTContext : public RefCountedBase<ASTContext> {
     return BoolName;
   }
 
-  IdentifierInfo *getMakeIntegerSeqName() const {
-    if (!MakeIntegerSeqName)
-      MakeIntegerSeqName = &Idents.get("__make_integer_seq");
-    return MakeIntegerSeqName;
-  }
-
-  IdentifierInfo *getTypePackElementName() const {
-    if (!TypePackElementName)
-      TypePackElementName = &Idents.get("__type_pack_element");
-    return TypePackElementName;
-  }
-
-  IdentifierInfo *getBuiltinCommonTypeName() const {
-    if (!BuiltinCommonTypeName)
-      BuiltinCommonTypeName = &Idents.get("__builtin_common_type");
-    return BuiltinCommonTypeName;
+#define BuiltinTemplate(BTName)                                                \
+  IdentifierInfo *get##BTName##Name() const {                                  \
+    if (!Name##BTName)                                                         \
+      Name##BTName = &Idents.get(#BTName);                                     \
+    return Name##BTName;                                                       \
   }
+#include "clang/Basic/BuiltinTemplates.inc"
 
   /// Retrieve the Objective-C "instancetype" type, if already known;
   /// otherwise, returns a NULL type;

clang/include/clang/AST/DeclID.h

@@ -71,20 +71,14 @@ enum PredefinedDeclIDs {
   /// The extern "C" context.
   PREDEF_DECL_EXTERN_C_CONTEXT_ID,
 
-  /// The internal '__make_integer_seq' template.
-  PREDEF_DECL_MAKE_INTEGER_SEQ_ID,
-
   /// The internal '__NSConstantString' typedef.
   PREDEF_DECL_CF_CONSTANT_STRING_ID,
 
   /// The internal '__NSConstantString' tag type.
   PREDEF_DECL_CF_CONSTANT_STRING_TAG_ID,
 
-  /// The internal '__type_pack_element' template.
-  PREDEF_DECL_TYPE_PACK_ELEMENT_ID,
-
-  /// The internal '__builtin_common_type' template.
-  PREDEF_DECL_COMMON_TYPE_ID,
+#define BuiltinTemplate(BTName) PREDEF_DECL##BTName##_ID,
+#include "clang/Basic/BuiltinTemplates.inc"
 
   /// The number of declaration IDs that are predefined.
   NUM_PREDEF_DECL_IDS

clang/include/clang/Basic/BuiltinTemplates.td

@@ -0,0 +1,52 @@
+//===--- BuiltinTemplates.td - Clang builtin template aliases ---*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+class TemplateArg<string name> {
+  string Name = name;
+}
+
+class Template<list<TemplateArg> args, string name> : TemplateArg<name> {
+  list<TemplateArg> Args = args;
+}
+
+class Class<string name, bit is_variadic = 0> : TemplateArg<name> {
+  bit IsVariadic = is_variadic;
+}
+
+class NTTP<string type_name, string name, bit is_variadic = 0> : TemplateArg<name> {
+  string TypeName = type_name;
+  bit IsVariadic = is_variadic;
+}
+
+class BuiltinNTTP<string type_name> : TemplateArg<""> {
+  string TypeName = type_name;
+}
+
+def SizeT : BuiltinNTTP<"size_t"> {}
+
+class BuiltinTemplate<list<TemplateArg> template_head> {
+  list<TemplateArg> TemplateHead = template_head;
+}
+
+// template <template <class T, T... Ints> IntSeq, class T, T N>
+def __make_integer_seq : BuiltinTemplate<
+  [Template<[Class<"T">, NTTP<"T", "Ints", /*is_variadic=*/1>], "IntSeq">, Class<"T">, NTTP<"T", "N">]>;
+
+// template <size_t, class... T>
+def __type_pack_element : BuiltinTemplate<
+  [SizeT, Class<"T", /*is_variadic=*/1>]>;
+
+// template <template <class... Args> BaseTemplate,
+//           template <class TypeMember> HasTypeMember,
+//           class HasNoTypeMember
+//           class... Ts>
+def __builtin_common_type : BuiltinTemplate<
+  [Template<[Class<"Args", /*is_variadic=*/1>], "BaseTemplate">,
+   Template<[Class<"TypeMember">], "HasTypeMember">,
+   Class<"HasNoTypeMember">,
+   Class<"Ts", /*is_variadic=*/1>]>;

clang/include/clang/Basic/Builtins.h

@@ -459,14 +459,8 @@ bool evaluateRequiredTargetFeatures(
 
 /// Kinds of BuiltinTemplateDecl.
 enum BuiltinTemplateKind : int {
-  /// This names the __make_integer_seq BuiltinTemplateDecl.
-  BTK__make_integer_seq,
-
-  /// This names the __type_pack_element BuiltinTemplateDecl.
-  BTK__type_pack_element,
-
-  /// This names the __builtin_common_type BuiltinTemplateDecl.
-  BTK__builtin_common_type,
+#define BuiltinTemplate(BTName) BTK##BTName,
+#include "clang/Basic/BuiltinTemplates.inc"
 };
 
 } // end namespace clang

clang/include/clang/Basic/CMakeLists.txt

@@ -96,6 +96,10 @@ clang_tablegen(BuiltinsX86_64.inc -gen-clang-builtins
   SOURCE BuiltinsX86_64.td
   TARGET ClangBuiltinsX86_64)
 
+clang_tablegen(BuiltinTemplates.inc -gen-clang-builtin-templates
+  SOURCE BuiltinTemplates.td
+  TARGET ClangBuiltinTemplates)
+
 # ARM NEON and MVE
 clang_tablegen(arm_neon.inc -gen-arm-neon-sema
   SOURCE arm_neon.td

clang/lib/AST/ASTContext.cpp

@@ -1198,28 +1198,14 @@ ASTContext::buildBuiltinTemplateDecl(BuiltinTemplateKind BTK,
   return BuiltinTemplate;
 }
 
-BuiltinTemplateDecl *
-ASTContext::getMakeIntegerSeqDecl() const {
-  if (!MakeIntegerSeqDecl)
-    MakeIntegerSeqDecl = buildBuiltinTemplateDecl(BTK__make_integer_seq,
-                                                  getMakeIntegerSeqName());
-  return MakeIntegerSeqDecl;
-}
-
-BuiltinTemplateDecl *
-ASTContext::getTypePackElementDecl() const {
-  if (!TypePackElementDecl)
-    TypePackElementDecl = buildBuiltinTemplateDecl(BTK__type_pack_element,
-                                                   getTypePackElementName());
-  return TypePackElementDecl;
-}
-
-BuiltinTemplateDecl *ASTContext::getBuiltinCommonTypeDecl() const {
-  if (!BuiltinCommonTypeDecl)
-    BuiltinCommonTypeDecl = buildBuiltinTemplateDecl(
-        BTK__builtin_common_type, getBuiltinCommonTypeName());
-  return BuiltinCommonTypeDecl;
-}
+#define BuiltinTemplate(BTName)                                                \
+  BuiltinTemplateDecl *ASTContext::get##BTName##Decl() const {                 \
+    if (!Decl##BTName)                                                         \
+      Decl##BTName =                                                           \
+          buildBuiltinTemplateDecl(BTK##BTName, get##BTName##Name());          \
+    return Decl##BTName;                                                       \
+  }
+#include "clang/Basic/BuiltinTemplates.inc"
 
 RecordDecl *ASTContext::buildImplicitRecord(StringRef Name,
                                             RecordDecl::TagKind TK) const {

clang/lib/AST/ASTImporter.cpp

@@ -5465,15 +5465,11 @@ ExpectedDecl ASTNodeImporter::VisitUnresolvedUsingTypenameDecl(
 ExpectedDecl ASTNodeImporter::VisitBuiltinTemplateDecl(BuiltinTemplateDecl *D) {
   Decl* ToD = nullptr;
   switch (D->getBuiltinTemplateKind()) {
-  case BuiltinTemplateKind::BTK__make_integer_seq:
-    ToD = Importer.getToContext().getMakeIntegerSeqDecl();
-    break;
-  case BuiltinTemplateKind::BTK__type_pack_element:
-    ToD = Importer.getToContext().getTypePackElementDecl();
-    break;
-  case BuiltinTemplateKind::BTK__builtin_common_type:
-    ToD = Importer.getToContext().getBuiltinCommonTypeDecl();
+#define BuiltinTemplate(BTName)                                                \
+  case BuiltinTemplateKind::BTK##BTName:                                       \
+    ToD = Importer.getToContext().get##BTName##Decl();                         \
     break;
+#include "clang/Basic/BuiltinTemplates.inc"
   }
   assert(ToD && "BuiltinTemplateDecl of unsupported kind!");
   Importer.MapImported(D, ToD);

clang/lib/AST/DeclTemplate.cpp

@@ -1581,140 +1581,11 @@ SourceRange VarTemplatePartialSpecializationDecl::getSourceRange() const {
   return Range;
 }
 
-static TemplateParameterList *
-createMakeIntegerSeqParameterList(const ASTContext &C, DeclContext *DC) {
-  // typename T
-  auto *T = TemplateTypeParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/1, /*Position=*/0,
-      /*Id=*/nullptr, /*Typename=*/true, /*ParameterPack=*/false,
-      /*HasTypeConstraint=*/false);
-  T->setImplicit(true);
-
-  // T ...Ints
-  TypeSourceInfo *TI =
-      C.getTrivialTypeSourceInfo(QualType(T->getTypeForDecl(), 0));
-  auto *N = NonTypeTemplateParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/1,
-      /*Id=*/nullptr, TI->getType(), /*ParameterPack=*/true, TI);
-  N->setImplicit(true);
-
-  // <typename T, T ...Ints>
-  NamedDecl *P[2] = {T, N};
-  auto *TPL = TemplateParameterList::Create(
-      C, SourceLocation(), SourceLocation(), P, SourceLocation(), nullptr);
-
-  // template <typename T, ...Ints> class IntSeq
-  auto *TemplateTemplateParm = TemplateTemplateParmDecl::Create(
-      C, DC, SourceLocation(), /*Depth=*/0, /*Position=*/0,
-      /*ParameterPack=*/false, /*Id=*/nullptr, /*Typename=*/false, TPL);
-  TemplateTemplateParm->setImplicit(true);
-
-  // typename T
-  auto *TemplateTypeParm = TemplateTypeParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/1,
-      /*Id=*/nullptr, /*Typename=*/true, /*ParameterPack=*/false,
-      /*HasTypeConstraint=*/false);
-  TemplateTypeParm->setImplicit(true);
-
-  // T N
-  TypeSourceInfo *TInfo = C.getTrivialTypeSourceInfo(
-      QualType(TemplateTypeParm->getTypeForDecl(), 0));
-  auto *NonTypeTemplateParm = NonTypeTemplateParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/2,
-      /*Id=*/nullptr, TInfo->getType(), /*ParameterPack=*/false, TInfo);
-  NamedDecl *Params[] = {TemplateTemplateParm, TemplateTypeParm,
-                         NonTypeTemplateParm};
-
-  // template <template <typename T, T ...Ints> class IntSeq, typename T, T N>
-  return TemplateParameterList::Create(C, SourceLocation(), SourceLocation(),
-                                       Params, SourceLocation(), nullptr);
-}
-
-static TemplateParameterList *
-createTypePackElementParameterList(const ASTContext &C, DeclContext *DC) {
-  // std::size_t Index
-  TypeSourceInfo *TInfo = C.getTrivialTypeSourceInfo(C.getSizeType());
-  auto *Index = NonTypeTemplateParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/0,
-      /*Id=*/nullptr, TInfo->getType(), /*ParameterPack=*/false, TInfo);
-
-  // typename ...T
-  auto *Ts = TemplateTypeParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/1,
-      /*Id=*/nullptr, /*Typename=*/true, /*ParameterPack=*/true,
-      /*HasTypeConstraint=*/false);
-  Ts->setImplicit(true);
-
-  // template <std::size_t Index, typename ...T>
-  NamedDecl *Params[] = {Index, Ts};
-  return TemplateParameterList::Create(C, SourceLocation(), SourceLocation(),
-                                       llvm::ArrayRef(Params), SourceLocation(),
-                                       nullptr);
-}
-
-static TemplateParameterList *createBuiltinCommonTypeList(const ASTContext &C,
-                                                          DeclContext *DC) {
-  // class... Args
-  auto *Args =
-      TemplateTypeParmDecl::Create(C, DC, SourceLocation(), SourceLocation(),
-                                   /*Depth=*/1, /*Position=*/0, /*Id=*/nullptr,
-                                   /*Typename=*/false, /*ParameterPack=*/true);
-
-  // <class... Args>
-  auto *BaseTemplateList = TemplateParameterList::Create(
-      C, SourceLocation(), SourceLocation(), Args, SourceLocation(), nullptr);
-
-  // template <class... Args> class BaseTemplate
-  auto *BaseTemplate = TemplateTemplateParmDecl::Create(
-      C, DC, SourceLocation(), /*Depth=*/0, /*Position=*/0,
-      /*ParameterPack=*/false, /*Id=*/nullptr,
-      /*Typename=*/false, BaseTemplateList);
-
-  // class TypeMember
-  auto *TypeMember =
-      TemplateTypeParmDecl::Create(C, DC, SourceLocation(), SourceLocation(),
-                                   /*Depth=*/1, /*Position=*/0, /*Id=*/nullptr,
-                                   /*Typename=*/false, /*ParameterPack=*/false);
-
-  // <class TypeMember>
-  auto *HasTypeMemberList =
-      TemplateParameterList::Create(C, SourceLocation(), SourceLocation(),
-                                    TypeMember, SourceLocation(), nullptr);
-
-  // template <class TypeMember> class HasTypeMember
-  auto *HasTypeMember = TemplateTemplateParmDecl::Create(
-      C, DC, SourceLocation(), /*Depth=*/0, /*Position=*/1,
-      /*ParameterPack=*/false, /*Id=*/nullptr,
-      /*Typename=*/false, HasTypeMemberList);
-
-  // class HasNoTypeMember
-  auto *HasNoTypeMember = TemplateTypeParmDecl::Create(
-      C, DC, {}, {}, /*Depth=*/0, /*Position=*/2, /*Id=*/nullptr,
-      /*Typename=*/false, /*ParameterPack=*/false);
-
-  // class... Ts
-  auto *Ts = TemplateTypeParmDecl::Create(
-      C, DC, SourceLocation(), SourceLocation(), /*Depth=*/0, /*Position=*/3,
-      /*Id=*/nullptr, /*Typename=*/false, /*ParameterPack=*/true);
-
-  // template <template <class... Args> class BaseTemplate,
-  //   template <class TypeMember> class HasTypeMember, class HasNoTypeMember,
-  //   class... Ts>
-  return TemplateParameterList::Create(
-      C, SourceLocation(), SourceLocation(),
-      {BaseTemplate, HasTypeMember, HasNoTypeMember, Ts}, SourceLocation(),
-      nullptr);
-}
-
 static TemplateParameterList *createBuiltinTemplateParameterList(
     const ASTContext &C, DeclContext *DC, BuiltinTemplateKind BTK) {
   switch (BTK) {
-  case BTK__make_integer_seq:
-    return createMakeIntegerSeqParameterList(C, DC);
-  case BTK__type_pack_element:
-    return createTypePackElementParameterList(C, DC);
-  case BTK__builtin_common_type:
-    return createBuiltinCommonTypeList(C, DC);
+#define CREATE_BUILTIN_TEMPLATE_PARAMETER_LIST
+#include "clang/Basic/BuiltinTemplates.inc"
   }
 
   llvm_unreachable("unhandled BuiltinTemplateKind!");

clang/lib/Lex/PPMacroExpansion.cpp

@@ -1831,10 +1831,9 @@ void Preprocessor::ExpandBuiltinMacro(Token &Tok) {
             return true;
           } else {
             return llvm::StringSwitch<bool>(II->getName())
-                // Report builtin templates as being builtins.
-                .Case("__make_integer_seq", getLangOpts().CPlusPlus)
-                .Case("__type_pack_element", getLangOpts().CPlusPlus)
-                .Case("__builtin_common_type", getLangOpts().CPlusPlus)
+        // Report builtin templates as being builtins.
+#define BuiltinTemplate(BTName) .Case(#BTName, getLangOpts().CPlusPlus)
+#include "clang/Basic/BuiltinTemplates.inc"
                 // Likewise for some builtin preprocessor macros.
                 // FIXME: This is inconsistent; we usually suggest detecting
                 // builtin macros via #ifdef. Don't add more cases here.