[clang] [Clang] Implement the core language parts of P2786 - Trivial relocation (PR #127636)

[via cfe-commits]

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@@ -2692,16 +2693,75 @@ bool Parser::isCXX11FinalKeyword() const {
          Specifier == VirtSpecifiers::VS_Sealed;
 }
 
+bool Parser::isCXX2CTriviallyRelocatableKeyword(Token Tok) const {
+  if (!getLangOpts().CPlusPlus || Tok.isNot(tok::identifier))
+    return false;
+  if (!Ident_trivially_relocatable_if_eligible)
+    Ident_trivially_relocatable_if_eligible =
+        &PP.getIdentifierTable().get("trivially_relocatable_if_eligible");
+  IdentifierInfo *II = Tok.getIdentifierInfo();
+  return II == Ident_trivially_relocatable_if_eligible;
+}
+
+bool Parser::isCXX2CTriviallyRelocatableKeyword() const {
+  return isCXX2CTriviallyRelocatableKeyword(Tok);
+}
+
+void Parser::ParseOptionalCXX2CTriviallyRelocatableSpecifier(
+    TriviallyRelocatableSpecifier &TRS) {
+  assert(isCXX2CTriviallyRelocatableKeyword() &&
+         "expected a trivially_relocatable specifier");
+
+  Diag(Tok.getLocation(), getLangOpts().CPlusPlus26
+                              ? diag::warn_relocatable_keyword
+                              : diag::ext_relocatable_keyword)
+      << /*relocatable*/ 0;
+
+  TRS = Actions.ActOnTriviallyRelocatableSpecifier(ConsumeToken());
+}
+
+bool Parser::isCXX2CReplaceableKeyword(Token Tok) const {
+  if (!getLangOpts().CPlusPlus || Tok.isNot(tok::identifier))
+    return false;
+  if (!Ident_replaceable_if_eligible)
+    Ident_replaceable_if_eligible =
+        &PP.getIdentifierTable().get("replaceable_if_eligible");
+  IdentifierInfo *II = Tok.getIdentifierInfo();
+  return II == Ident_replaceable_if_eligible;
+}
+
+bool Parser::isCXX2CReplaceableKeyword() const {
+  return isCXX2CReplaceableKeyword(Tok);
+}
+
+void Parser::ParseOptionalCXX2CReplaceableSpecifier(ReplaceableSpecifier &MRS) {
+  assert(isCXX2CReplaceableKeyword() &&
+         "expected a replaceable_if_eligible specifier");
+
+  Diag(Tok.getLocation(), getLangOpts().CPlusPlus26
+                              ? diag::warn_relocatable_keyword
+                              : diag::ext_relocatable_keyword)
+      << /*replaceable*/ 1;
+
+  MRS = Actions.ActOnReplaceableSpecifier(ConsumeToken());
+}
+
 /// isClassCompatibleKeyword - Determine whether the next token is a C++11
 /// 'final' or Microsoft 'sealed' or 'abstract' contextual keywords.
----------------
Sirraide wrote:

nit: we might want to update this comment now

https://github.com/llvm/llvm-project/pull/127636