[arcmt] NSInvocation's [get/set]ReturnValue and [get/set]Argument are only safe

with __unsafe_unretained parameters. Emit error for strong/weak ones. rdar://9206226

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135381 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 89 insertions, 0 deletions

diff --git a/lib/ARCMigrate/TransAPIUses.cpp b/lib/ARCMigrate/TransAPIUses.cpp
new file mode 100644
index 0000000000..58fd3d07d0
--- /dev/null
+++ b/lib/ARCMigrate/TransAPIUses.cpp
@@ -0,0 +1,89 @@
+//===--- TransAPIUses.cpp - Tranformations to ARC mode --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// checkAPIUses:
+//
+// Emits error with some API uses that are not safe in ARC mode:
+//
+// - NSInvocation's [get/set]ReturnValue and [get/set]Argument are only safe
+//   with __unsafe_unretained objects.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Transforms.h"
+#include "Internals.h"
+
+using namespace clang;
+using namespace arcmt;
+using namespace trans;
+using llvm::StringRef;
+
+namespace {
+
+class APIChecker : public RecursiveASTVisitor<APIChecker> {
+  MigrationPass &Pass;
+  Selector getReturnValueSel, setReturnValueSel;
+  Selector getArgumentSel, setArgumentSel;
+
+public:
+  APIChecker(MigrationPass &pass) : Pass(pass) {
+    SelectorTable &sels = Pass.Ctx.Selectors;
+    IdentifierTable &ids = Pass.Ctx.Idents;
+    getReturnValueSel = sels.getUnarySelector(&ids.get("getReturnValue"));
+    setReturnValueSel = sels.getUnarySelector(&ids.get("setReturnValue"));
+
+    IdentifierInfo *selIds[2];
+    selIds[0] = &ids.get("getArgument");
+    selIds[1] = &ids.get("atIndex");
+    getArgumentSel = sels.getSelector(2, selIds);
+    selIds[0] = &ids.get("setArgument");
+    setArgumentSel = sels.getSelector(2, selIds);
+  }
+
+  bool VisitObjCMessageExpr(ObjCMessageExpr *E) {
+    if (E->isInstanceMessage() &&
+        E->getReceiverInterface() &&
+        E->getReceiverInterface()->getName() == "NSInvocation") {
+      StringRef selName;
+      if (E->getSelector() == getReturnValueSel)
+        selName = "getReturnValue";
+      else if (E->getSelector() == setReturnValueSel)
+        selName = "setReturnValue";
+      else if (E->getSelector() == getArgumentSel)
+        selName = "getArgument";
+      else if (E->getSelector() == setArgumentSel)
+        selName = "setArgument";
+
+      if (selName.empty())
+        return true;
+
+      Expr *parm = E->getArg(0)->IgnoreParenCasts();
+      QualType pointee = parm->getType()->getPointeeType();
+      if (pointee.isNull())
+        return true;
+
+      if (pointee.getObjCLifetime() > Qualifiers::OCL_ExplicitNone) {
+        std::string err = "NSInvocation's ";
+        err += selName;
+        err += " is not safe to be used with an object with ownership other "
+            "than __unsafe_unretained";
+        Pass.TA.reportError(err, parm->getLocStart(), parm->getSourceRange());
+      }
+      return true;
+    }
+
+    return true;
+  }
+};
+
+} // anonymous namespace
+
+void trans::checkAPIUses(MigrationPass &pass) {
+  APIChecker(pass).TraverseDecl(pass.Ctx.getTranslationUnitDecl());
+}