llvm-project/clang/lib/ARCMigrate/TransProtectedScope.cpp

119 lines
3.7 KiB
C++

//===--- 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;
}
}