Add explicit attributes to mark functions as having had their

CoreFoundation object-transfer properties audited, and add a #pragma
to cause them to be automatically applied to functions in a particular
span of code.  This has to be implemented largely in the preprocessor
because of the requirement that the region be entirely contained in
a single file;  that's hard to impose from the parser without registering
for a ton of callbacks.

llvm-svn: 140846

1 files changed, 55 insertions, 0 deletions

diff --git a/clang/lib/Lex/Pragma.cpp b/clang/lib/Lex/Pragma.cpp
index d855baf9e29..f6532c2175a 100644
--- a/clang/lib/Lex/Pragma.cpp
+++ b/clang/lib/Lex/Pragma.cpp
@@ -1005,6 +1005,60 @@ struct PragmaSTDC_UnknownHandler : public PragmaHandler {
   }
 };
 
+/// PragmaARCCFCodeAuditedHandler - 
+///   #pragma clang arc_cf_code_audited begin/end
+struct PragmaARCCFCodeAuditedHandler : public PragmaHandler {
+  PragmaARCCFCodeAuditedHandler() : PragmaHandler("arc_cf_code_audited") {}
+  virtual void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
+                            Token &NameTok) {
+    SourceLocation Loc = NameTok.getLocation();
+    bool IsBegin;
+
+    Token Tok;
+
+    // Lex the 'begin' or 'end'.
+    PP.LexUnexpandedToken(Tok);
+    const IdentifierInfo *BeginEnd = Tok.getIdentifierInfo();
+    if (BeginEnd && BeginEnd->isStr("begin")) {
+      IsBegin = true;
+    } else if (BeginEnd && BeginEnd->isStr("end")) {
+      IsBegin = false;
+    } else {
+      PP.Diag(Tok.getLocation(), diag::err_pp_arc_cf_code_audited_syntax);
+      return;
+    }
+
+    // Verify that this is followed by EOD.
+    PP.LexUnexpandedToken(Tok);
+    if (Tok.isNot(tok::eod))
+      PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma";
+
+    // The start location of the active audit.
+    SourceLocation BeginLoc = PP.getPragmaARCCFCodeAuditedLoc();
+
+    // The start location we want after processing this.
+    SourceLocation NewLoc;
+
+    if (IsBegin) {
+      // Complain about attempts to re-enter an audit.
+      if (BeginLoc.isValid()) {
+        PP.Diag(Loc, diag::err_pp_double_begin_of_arc_cf_code_audited);
+        PP.Diag(BeginLoc, diag::note_pragma_entered_here);
+      }
+      NewLoc = Loc;
+    } else {
+      // Complain about attempts to leave an audit that doesn't exist.
+      if (!BeginLoc.isValid()) {
+        PP.Diag(Loc, diag::err_pp_unmatched_end_of_arc_cf_code_audited);
+        return;
+      }
+      NewLoc = SourceLocation();
+    }
+
+    PP.setPragmaARCCFCodeAuditedLoc(NewLoc);
+  }
+};
+
 }  // end anonymous namespace
 
 
@@ -1028,6 +1082,7 @@ void Preprocessor::RegisterBuiltinPragmas() {
   AddPragmaHandler("clang", new PragmaDebugHandler());
   AddPragmaHandler("clang", new PragmaDependencyHandler());
   AddPragmaHandler("clang", new PragmaDiagnosticHandler("clang"));
+  AddPragmaHandler("clang", new PragmaARCCFCodeAuditedHandler());
 
   AddPragmaHandler("STDC", new PragmaSTDC_FENV_ACCESSHandler());
   AddPragmaHandler("STDC", new PragmaSTDC_CX_LIMITED_RANGEHandler());