[arcmt] Adds brackets in case statements that "contain" initialization of retaining
variable, thus emitting the "switch case is in protected scope" error.
rdar://12952016
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171484 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/ARCMigrate/TransProtectedScope.cpp b/lib/ARCMigrate/TransProtectedScope.cpp
new file mode 100644
index 0000000..b202600
--- /dev/null
+++ b/lib/ARCMigrate/TransProtectedScope.cpp
@@ -0,0 +1,118 @@
+//===--- TransProtectedScope.cpp - Transformations to ARC mode ------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Adds brackets in case statements that "contain" initialization of retaining
+// variable, thus emitting the "switch case is in protected scope" error.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Transforms.h"
+#include "Internals.h"
+#include "clang/Sema/SemaDiagnostic.h"
+
+using namespace clang;
+using namespace arcmt;
+using namespace trans;
+
+namespace {
+
+struct CaseInfo {
+ SwitchCase *SC;
+ SourceRange Range;
+ bool FixedBypass;
+
+ CaseInfo() : SC(0), FixedBypass(false) {}
+ CaseInfo(SwitchCase *S, SourceRange Range)
+ : SC(S), Range(Range), FixedBypass(false) {}
+};
+
+class CaseCollector : public RecursiveASTVisitor<CaseCollector> {
+ llvm::SmallVectorImpl<CaseInfo> &Cases;
+
+public:
+ CaseCollector(llvm::SmallVectorImpl<CaseInfo> &Cases)
+ : Cases(Cases) { }
+
+ bool VisitSwitchStmt(SwitchStmt *S) {
+ SourceLocation NextLoc = S->getLocEnd();
+ SwitchCase *Curr = S->getSwitchCaseList();
+ // We iterate over case statements in reverse source-order.
+ while (Curr) {
+ Cases.push_back(CaseInfo(Curr,SourceRange(Curr->getLocStart(), NextLoc)));
+ NextLoc = Curr->getLocStart();
+ Curr = Curr->getNextSwitchCase();
+ }
+ return true;
+ }
+};
+
+} // anonymous namespace
+
+static bool isInRange(FullSourceLoc Loc, SourceRange R) {
+ return !Loc.isBeforeInTranslationUnitThan(R.getBegin()) &&
+ Loc.isBeforeInTranslationUnitThan(R.getEnd());
+}
+
+static bool handleProtectedNote(const StoredDiagnostic &Diag,
+ llvm::SmallVectorImpl<CaseInfo> &Cases,
+ TransformActions &TA) {
+ assert(Diag.getLevel() == DiagnosticsEngine::Note);
+
+ for (unsigned i = 0; i != Cases.size(); i++) {
+ CaseInfo &info = Cases[i];
+ if (isInRange(Diag.getLocation(), info.Range)) {
+ TA.clearDiagnostic(Diag.getID(), Diag.getLocation());
+ if (!info.FixedBypass) {
+ TA.insertAfterToken(info.SC->getColonLoc(), " {");
+ TA.insert(info.Range.getEnd(), "}\n");
+ info.FixedBypass = true;
+ }
+ return true;
+ }
+ }
+
+ return false;
+}
+
+static void handleProtectedScopeError(CapturedDiagList::iterator &DiagI,
+ CapturedDiagList::iterator DiagE,
+ llvm::SmallVectorImpl<CaseInfo> &Cases,
+ TransformActions &TA) {
+ Transaction Trans(TA);
+ assert(DiagI->getID() == diag::err_switch_into_protected_scope);
+ SourceLocation ErrLoc = DiagI->getLocation();
+ bool handledAllNotes = true;
+ ++DiagI;
+ for (; DiagI != DiagE && DiagI->getLevel() == DiagnosticsEngine::Note;
+ ++DiagI) {
+ if (!handleProtectedNote(*DiagI, Cases, TA))
+ handledAllNotes = false;
+ }
+
+ if (handledAllNotes)
+ TA.clearDiagnostic(diag::err_switch_into_protected_scope, ErrLoc);
+}
+
+void ProtectedScopeTraverser::traverseBody(BodyContext &BodyCtx) {
+ MigrationPass &Pass = BodyCtx.getMigrationContext().Pass;
+ SmallVector<CaseInfo, 16> Cases;
+ CaseCollector(Cases).TraverseStmt(BodyCtx.getTopStmt());
+
+ SourceRange BodyRange = BodyCtx.getTopStmt()->getSourceRange();
+ const CapturedDiagList &DiagList = Pass.getDiags();
+ CapturedDiagList::iterator I = DiagList.begin(), E = DiagList.end();
+ while (I != E) {
+ if (I->getID() == diag::err_switch_into_protected_scope &&
+ isInRange(I->getLocation(), BodyRange)) {
+ handleProtectedScopeError(I, E, Cases, Pass.TA);
+ continue;
+ }
+ ++I;
+ }
+}