arc migrator: Provide infrastructure to add options

specific to migrator. Use its first option to
warn migrating from GC to arc when 
NSAllocateCollectable/NSReallocateCollectable is used.
// rdar://10532541

llvm-svn: 148887

clang/include/clang/Driver/CC1Options.td

@@ -100,6 +100,12 @@ def analyzer_disable_checker_EQ : Joined<"-analyzer-disable-checker=">,
 def analyzer_checker_help : Flag<"-analyzer-checker-help">,
   HelpText<"Display the list of analyzer checkers that are available">;
 
+//===----------------------------------------------------------------------===//
+// Migrator Options
+//===----------------------------------------------------------------------===//
+def migrator_no_nsalloc_error : Flag<"-no-ns-alloc-error">,
+  HelpText<"Do not error on use of NSAllocateCollectable/NSReallocateCollectable">;
+
 //===----------------------------------------------------------------------===//
 // CodeGen Options
 //===----------------------------------------------------------------------===//

clang/include/clang/Frontend/CompilerInvocation.h

@@ -14,6 +14,7 @@
 #include "clang/Basic/TargetOptions.h"
 #include "clang/Basic/FileSystemOptions.h"
 #include "clang/Frontend/AnalyzerOptions.h"
+#include "clang/Frontend/MigratorOptions.h"
 #include "clang/Frontend/CodeGenOptions.h"
 #include "clang/Frontend/DependencyOutputOptions.h"
 #include "clang/Frontend/DiagnosticOptions.h"
@@ -56,6 +57,8 @@ class CompilerInvocation : public CompilerInvocationBase {
   /// Options controlling the static analyzer.
   AnalyzerOptions AnalyzerOpts;
 
+  MigratorOptions MigratorOpts;
+  
   /// Options controlling IRgen and the backend.
   CodeGenOptions CodeGenOpts;
 
@@ -147,6 +150,11 @@ public:
     return AnalyzerOpts;
   }
 
+  MigratorOptions &getMigratorOpts() { return MigratorOpts; }
+  const MigratorOptions &getMigratorOpts() const {
+    return MigratorOpts;
+  }
+  
   CodeGenOptions &getCodeGenOpts() { return CodeGenOpts; }
   const CodeGenOptions &getCodeGenOpts() const {
     return CodeGenOpts;

clang/include/clang/Frontend/MigratorOptions.h

@@ -0,0 +1,29 @@
+//===--- MigratorOptions.h - MigratorOptions Options ------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This header contains the structures necessary for a front-end to specify
+// various migration analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_FRONTEND_MIGRATOROPTIONS
+#define LLVM_CLANG_FRONTEND_MIGRATOROPTIONS
+
+namespace clang {
+
+class MigratorOptions {
+public:
+  unsigned NoNSAllocReallocError : 1;
+  MigratorOptions() {
+    NoNSAllocReallocError = 0;
+  }
+};
+
+}
+#endif

clang/lib/ARCMigrate/ARCMT.cpp

@@ -229,6 +229,7 @@ bool arcmt::checkForManualIssues(CompilerInvocation &origCI,
     return false;
 
   LangOptions::GCMode OrigGCMode = origCI.getLangOpts()->getGC();
+  bool NoNSAllocReallocError = origCI.getMigratorOpts().NoNSAllocReallocError;
 
   std::vector<TransformFn> transforms = arcmt::getAllTransformations(OrigGCMode);
   assert(!transforms.empty());
@@ -292,6 +293,7 @@ bool arcmt::checkForManualIssues(CompilerInvocation &origCI,
 
   TransformActions testAct(*Diags, capturedDiags, Ctx, Unit->getPreprocessor());
   MigrationPass pass(Ctx, OrigGCMode, Unit->getSema(), testAct, ARCMTMacroLocs);
+  pass.setNSAllocReallocError(NoNSAllocReallocError);
 
   for (unsigned i=0, e = transforms.size(); i != e; ++i)
     transforms[i](pass);

clang/lib/ARCMigrate/Internals.h

@@ -94,6 +94,8 @@ public:
 
   void reportError(StringRef error, SourceLocation loc,
                    SourceRange range = SourceRange());
+  void reportWarning(StringRef warning, SourceLocation loc,
+                   SourceRange range = SourceRange());
   void reportNote(StringRef note, SourceLocation loc,
                   SourceRange range = SourceRange());
 
@@ -138,6 +140,7 @@ class MigrationPass {
 public:
   ASTContext &Ctx;
   LangOptions::GCMode OrigGCMode;
+  MigratorOptions MigOptions;
   Sema &SemaRef;
   TransformActions &TA;
   std::vector<SourceLocation> &ARCMTMacroLocs;
@@ -145,10 +148,13 @@ public:
   MigrationPass(ASTContext &Ctx, LangOptions::GCMode OrigGCMode,
                 Sema &sema, TransformActions &TA,
                 std::vector<SourceLocation> &ARCMTMacroLocs)
-    : Ctx(Ctx), OrigGCMode(OrigGCMode), SemaRef(sema), TA(TA),
+    : Ctx(Ctx), OrigGCMode(OrigGCMode), MigOptions(),
+      SemaRef(sema), TA(TA),
       ARCMTMacroLocs(ARCMTMacroLocs) { }
 
   bool isGCMigration() const { return OrigGCMode != LangOptions::NonGC; }
+  bool noNSAllocReallocError() const { return MigOptions.NoNSAllocReallocError; }
+  void setNSAllocReallocError(bool val) { MigOptions.NoNSAllocReallocError = val; }
 };
 
 static inline StringRef getARCMTMacroName() {

clang/lib/ARCMigrate/TransGCCalls.cpp

@@ -38,9 +38,14 @@ public:
     TransformActions &TA = MigrateCtx.Pass.TA;
 
     if (MigrateCtx.isGCOwnedNonObjC(E->getType())) {
-      TA.reportError("call returns pointer to GC managed memory; "
-                     "it will become unmanaged in ARC",
-                     E->getLocStart(), E->getSourceRange());
+      if (MigrateCtx.Pass.noNSAllocReallocError())
+        TA.reportWarning("call returns pointer to GC managed memory; "
+                       "it will become unmanaged in ARC",
+                       E->getLocStart(), E->getSourceRange());
+      else 
+        TA.reportError("call returns pointer to GC managed memory; "
+                       "it will become unmanaged in ARC",
+                       E->getLocStart(), E->getSourceRange());
       return true;
     }
 

clang/lib/ARCMigrate/TransformActions.cpp

@@ -692,6 +692,25 @@ void TransformActions::reportError(StringRef error, SourceLocation loc,
   ReportedErrors = true;
 }
 
+void TransformActions::reportWarning(StringRef warning, SourceLocation loc,
+                                   SourceRange range) {
+  assert(!static_cast<TransformActionsImpl*>(Impl)->isInTransaction() &&
+         "Warning should be emitted out of a transaction");
+  
+  SourceManager &SM = static_cast<TransformActionsImpl*>(Impl)->
+    getASTContext().getSourceManager();
+  if (SM.isInSystemHeader(SM.getExpansionLoc(loc)))
+    return;
+  
+  // FIXME: Use a custom category name to distinguish rewriter errors.
+  std::string rewriterWarn = "[rewriter] ";
+  rewriterWarn += warning;
+  unsigned diagID
+  = Diags.getDiagnosticIDs()->getCustomDiagID(DiagnosticIDs::Warning,
+                                              rewriterWarn);
+  Diags.Report(loc, diagID) << range;
+}
+
 void TransformActions::reportNote(StringRef note, SourceLocation loc,
                                   SourceRange range) {
   assert(!static_cast<TransformActionsImpl*>(Impl)->isInTransaction() &&

clang/lib/Frontend/CompilerInvocation.cpp

@@ -1053,6 +1053,11 @@ static bool ParseAnalyzerArgs(AnalyzerOptions &Opts, ArgList &Args,
   return Success;
 }
 
+static bool ParseMigratorArgs(MigratorOptions &Opts, ArgList &Args) {
+  Opts.NoNSAllocReallocError = Args.hasArg(OPT_migrator_no_nsalloc_error);
+  return true;
+}
+
 static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
                              DiagnosticsEngine &Diags) {
   using namespace cc1options;
@@ -2051,6 +2056,7 @@ bool CompilerInvocation::CreateFromArgs(CompilerInvocation &Res,
   }
 
   Success = ParseAnalyzerArgs(Res.getAnalyzerOpts(), *Args, Diags) && Success;
+  Success = ParseMigratorArgs(Res.getMigratorOpts(), *Args) && Success;
   ParseDependencyOutputArgs(Res.getDependencyOutputOpts(), *Args);
   Success = ParseDiagnosticArgs(Res.getDiagnosticOpts(), *Args, Diags)
             && Success;

clang/test/ARCMT/GC-check-warn-nsalloc.m

@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 -arcmt-check -verify -no-ns-alloc-error -triple x86_64-apple-darwin10 -fobjc-gc-only %s
+// RUN: %clang_cc1 -arcmt-check -verify -no-ns-alloc-error -triple x86_64-apple-darwin10 -fobjc-gc-only -x objective-c++ %s
+// DISABLE: mingw32
+// rdar://10532541
+// XFAIL: *
+
+typedef unsigned NSUInteger;
+void *__strong NSAllocateCollectable(NSUInteger size, NSUInteger options);
+
+void test1() {
+  NSAllocateCollectable(100, 0); // expected-warning {{call returns pointer to GC managed memory; it will become unmanaged in ARC}}
+}