//===--- DiagnosticRenderer.cpp - Diagnostic Pretty-Printing --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "clang/Frontend/DiagnosticRenderer.h"
#include "clang/Basic/DiagnosticOptions.h"
#include "clang/Basic/FileManager.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Edit/Commit.h"
#include "clang/Edit/EditedSource.h"
#include "clang/Edit/EditsReceiver.h"
#include "clang/Lex/Lexer.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
using namespace clang;
/// \brief Retrieve the name of the immediate macro expansion.
///
/// This routine starts from a source location, and finds the name of the macro
/// responsible for its immediate expansion. It looks through any intervening
/// macro argument expansions to compute this. It returns a StringRef which
/// refers to the SourceManager-owned buffer of the source where that macro
/// name is spelled. Thus, the result shouldn't out-live that SourceManager.
///
/// This differs from Lexer::getImmediateMacroName in that any macro argument
/// location will result in the topmost function macro that accepted it.
/// e.g.
/// \code
/// MAC1( MAC2(foo) )
/// \endcode
/// for location of 'foo' token, this function will return "MAC1" while
/// Lexer::getImmediateMacroName will return "MAC2".
static StringRef getImmediateMacroName(SourceLocation Loc,
const SourceManager &SM,
const LangOptions &LangOpts) {
assert(Loc.isMacroID() && "Only reasonble to call this on macros");
// Walk past macro argument expanions.
while (SM.isMacroArgExpansion(Loc))
Loc = SM.getImmediateExpansionRange(Loc).first;
// If the macro's spelling has no FileID, then it's actually a token paste
// or stringization (or similar) and not a macro at all.
if (!SM.getFileEntryForID(SM.getFileID(SM.getSpellingLoc(Loc))))
return StringRef();
// Find the spelling location of the start of the non-argument expansion
// range. This is where the macro name was spelled in order to begin
// expanding this macro.
Loc = SM.getSpellingLoc(SM.getImmediateExpansionRange(Loc).first);
// Dig out the buffer where the macro name was spelled and the extents of the
// name so that we can render it into the expansion note.
std::pair<FileID, unsigned> ExpansionInfo = SM.getDecomposedLoc(Loc);
unsigned MacroTokenLength = Lexer::MeasureTokenLength(Loc, SM, LangOpts);
StringRef ExpansionBuffer = SM.getBufferData(ExpansionInfo.first);
return ExpansionBuffer.substr(ExpansionInfo.second, MacroTokenLength);
}
DiagnosticRenderer::DiagnosticRenderer(const LangOptions &LangOpts,
DiagnosticOptions *DiagOpts)
: LangOpts(LangOpts), DiagOpts(DiagOpts), LastLevel() {}
DiagnosticRenderer::~DiagnosticRenderer() {}
namespace {
class FixitReceiver : public edit::EditsReceiver {
SmallVectorImpl<FixItHint> &MergedFixits;
public:
FixitReceiver(SmallVectorImpl<FixItHint> &MergedFixits)
: MergedFixits(MergedFixits) { }
void insert(SourceLocation loc, StringRef text) override {
MergedFixits.push_back(FixItHint::CreateInsertion(loc, text));
}
void replace(CharSourceRange range, StringRef text) override {
MergedFixits.push_back(FixItHint::CreateReplacement(range, text));
}
};
}
static void mergeFixits(ArrayRef<FixItHint> FixItHints,
const SourceManager &SM, const LangOptions &LangOpts,
SmallVectorImpl<FixItHint> &MergedFixits) {
edit::Commit commit(SM, LangOpts);
for (ArrayRef<FixItHint>::const_iterator
I = FixItHints.begin(), E = FixItHints.end(); I != E; ++I) {
const FixItHint &Hint = *I;
if (Hint.CodeToInsert.empty()) {
if (Hint.InsertFromRange.isValid())
commit.insertFromRange(Hint.RemoveRange.getBegin(),
Hint.InsertFromRange, /*afterToken=*/false,
Hint.BeforePreviousInsertions);
else
commit.remove(Hint.RemoveRange);
} else {
if (Hint.RemoveRange.isTokenRange() ||
Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
else
commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
/*afterToken=*/false, Hint.BeforePreviousInsertions);
}
}
edit::EditedSource Editor(SM, LangOpts);
if (Editor.commit(commit)) {
FixitReceiver Rec(MergedFixits);
Editor.applyRewrites(Rec);
}
}
void DiagnosticRenderer::emitDiagnostic(SourceLocation Loc,
DiagnosticsEngine::Level Level,
StringRef Message,
ArrayRef<CharSourceRange> Ranges,
ArrayRef<FixItHint> FixItHints,
const SourceManager *SM,
DiagOrStoredDiag D) {
assert(SM || Loc.isInvalid());
beginDiagnostic(D, Level);
if (!Loc.isValid())
// If we have no source location, just emit the diagnostic message.
emitDiagnosticMessage(Loc, PresumedLoc(), Level, Message, Ranges, SM, D);
else {
// Get the ranges into a local array we can hack on.
SmallVector<CharSourceRange, 20> MutableRanges(Ranges.begin(),
Ranges.end());
SmallVector<FixItHint, 8> MergedFixits;
if (!FixItHints.empty()) {
mergeFixits(FixItHints, *SM, LangOpts, MergedFixits);
FixItHints = MergedFixits;
}
for (ArrayRef<FixItHint>::const_iterator I = FixItHints.begin(),
E = FixItHints.end();
I != E; ++I)
if (I->RemoveRange.isValid())
MutableRanges.push_back(I->RemoveRange);
SourceLocation UnexpandedLoc = Loc;
// Find the ultimate expansion location for the diagnostic.
Loc = SM->getFileLoc(Loc);
PresumedLoc PLoc = SM->getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
// First, if this diagnostic is not in the main file, print out the
// "included from" lines.
emitIncludeStack(Loc, PLoc, Level, *SM);
// Next, emit the actual diagnostic message and caret.
emitDiagnosticMessage(Loc, PLoc, Level, Message, Ranges, SM, D);
emitCaret(Loc, Level, MutableRanges, FixItHints, *SM);
// If this location is within a macro, walk from UnexpandedLoc up to Loc
// and produce a macro backtrace.
if (UnexpandedLoc.isValid() && UnexpandedLoc.isMacroID()) {
unsigned MacroDepth = 0;
emitMacroExpansions(UnexpandedLoc, Level, MutableRanges, FixItHints, *SM,
MacroDepth);
}
}
LastLoc = Loc;
LastLevel = Level;
endDiagnostic(D, Level);
}
void DiagnosticRenderer::emitStoredDiagnostic(StoredDiagnostic &Diag) {
emitDiagnostic(Diag.getLocation(), Diag.getLevel(), Diag.getMessage(),
Diag.getRanges(), Diag.getFixIts(),
Diag.getLocation().isValid() ? &Diag.getLocation().getManager()
: nullptr,
&Diag);
}
void DiagnosticRenderer::emitBasicNote(StringRef Message) {
emitDiagnosticMessage(
SourceLocation(), PresumedLoc(), DiagnosticsEngine::Note, Message,
ArrayRef<CharSourceRange>(), nullptr, DiagOrStoredDiag());
}
/// \brief Prints an include stack when appropriate for a particular
/// diagnostic level and location.
///
/// This routine handles all the logic of suppressing particular include
/// stacks (such as those for notes) and duplicate include stacks when
/// repeated warnings occur within the same file. It also handles the logic
/// of customizing the formatting and display of the include stack.
///
/// \param Loc The diagnostic location.
/// \param PLoc The presumed location of the diagnostic location.
/// \param Level The diagnostic level of the message this stack pertains to.
void DiagnosticRenderer::emitIncludeStack(SourceLocation Loc,
PresumedLoc PLoc,
DiagnosticsEngine::Level Level,
const SourceManager &SM) {
SourceLocation IncludeLoc = PLoc.getIncludeLoc();
// Skip redundant include stacks altogether.
if (LastIncludeLoc == IncludeLoc)
return;
LastIncludeLoc = IncludeLoc;
if (!DiagOpts->ShowNoteIncludeStack && Level == DiagnosticsEngine::Note)
return;
if (IncludeLoc.isValid())
emitIncludeStackRecursively(IncludeLoc, SM);
else {
emitModuleBuildStack(SM);
emitImportStack(Loc, SM);
}
}
/// \brief Helper to recursivly walk up the include stack and print each layer
/// on the way back down.
void DiagnosticRenderer::emitIncludeStackRecursively(SourceLocation Loc,
const SourceManager &SM) {
if (Loc.isInvalid()) {
emitModuleBuildStack(SM);
return;
}
PresumedLoc PLoc = SM.getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
if (PLoc.isInvalid())
return;
// If this source location was imported from a module, print the module
// import stack rather than the
// FIXME: We want submodule granularity here.
std::pair<SourceLocation, StringRef> Imported = SM.getModuleImportLoc(Loc);
if (Imported.first.isValid()) {
// This location was imported by a module. Emit the module import stack.
emitImportStackRecursively(Imported.first, Imported.second, SM);
return;
}
// Emit the other include frames first.
emitIncludeStackRecursively(PLoc.getIncludeLoc(), SM);
// Emit the inclusion text/note.
emitIncludeLocation(Loc, PLoc, SM);
}
/// \brief Emit the module import stack associated with the current location.
void DiagnosticRenderer::emitImportStack(SourceLocation Loc,
const SourceManager &SM) {
if (Loc.isInvalid()) {
emitModuleBuildStack(SM);
return;
}
std::pair<SourceLocation, StringRef> NextImportLoc
= SM.getModuleImportLoc(Loc);
emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second, SM);
}
/// \brief Helper to recursivly walk up the import stack and print each layer
/// on the way back down.
void DiagnosticRenderer::emitImportStackRecursively(SourceLocation Loc,
StringRef ModuleName,
const SourceManager &SM) {
if (Loc.isInvalid()) {
return;
}
PresumedLoc PLoc = SM.getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
if (PLoc.isInvalid())
return;
// Emit the other import frames first.
std::pair<SourceLocation, StringRef> NextImportLoc
= SM.getModuleImportLoc(Loc);
emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second, SM);
// Emit the inclusion text/note.
emitImportLocation(Loc, PLoc, ModuleName, SM);
}
/// \brief Emit the module build stack, for cases where a module is (re-)built
/// on demand.
void DiagnosticRenderer::emitModuleBuildStack(const SourceManager &SM) {
ModuleBuildStack Stack = SM.getModuleBuildStack();
for (unsigned I = 0, N = Stack.size(); I != N; ++I) {
const SourceManager &CurSM = Stack[I].second.getManager();
SourceLocation CurLoc = Stack[I].second;
emitBuildingModuleLocation(CurLoc,
CurSM.getPresumedLoc(CurLoc,
DiagOpts->ShowPresumedLoc),
Stack[I].first,
CurSM);
}
}
// Helper function to fix up source ranges. It takes in an array of ranges,
// and outputs an array of ranges where we want to draw the range highlighting
// around the location specified by CaretLoc.
//
// To find locations which correspond to the caret, we crawl the macro caller
// chain for the beginning and end of each range. If the caret location
// is in a macro expansion, we search each chain for a location
// in the same expansion as the caret; otherwise, we crawl to the top of
// each chain. Two locations are part of the same macro expansion
// iff the FileID is the same.
static void mapDiagnosticRanges(
SourceLocation CaretLoc,
ArrayRef<CharSourceRange> Ranges,
SmallVectorImpl<CharSourceRange> &SpellingRanges,
const SourceManager *SM) {
FileID CaretLocFileID = SM->getFileID(CaretLoc);
for (ArrayRef<CharSourceRange>::const_iterator I = Ranges.begin(),
E = Ranges.end();
I != E; ++I) {
SourceLocation Begin = I->getBegin(), End = I->getEnd();
bool IsTokenRange = I->isTokenRange();
FileID BeginFileID = SM->getFileID(Begin);
FileID EndFileID = SM->getFileID(End);
// Find the common parent for the beginning and end of the range.
// First, crawl the expansion chain for the beginning of the range.
llvm::SmallDenseMap<FileID, SourceLocation> BeginLocsMap;
while (Begin.isMacroID() && BeginFileID != EndFileID) {
BeginLocsMap[BeginFileID] = Begin;
Begin = SM->getImmediateExpansionRange(Begin).first;
BeginFileID = SM->getFileID(Begin);
}
// Then, crawl the expansion chain for the end of the range.
if (BeginFileID != EndFileID) {
while (End.isMacroID() && !BeginLocsMap.count(EndFileID)) {
End = SM->getImmediateExpansionRange(End).second;
EndFileID = SM->getFileID(End);
}
if (End.isMacroID()) {
Begin = BeginLocsMap[EndFileID];
BeginFileID = EndFileID;
}
}
while (Begin.isMacroID() && BeginFileID != CaretLocFileID) {
if (SM->isMacroArgExpansion(Begin)) {
Begin = SM->getImmediateSpellingLoc(Begin);
End = SM->getImmediateSpellingLoc(End);
} else {
Begin = SM->getImmediateExpansionRange(Begin).first;
End = SM->getImmediateExpansionRange(End).second;
}
BeginFileID = SM->getFileID(Begin);
if (BeginFileID != SM->getFileID(End)) {
// FIXME: Ugly hack to stop a crash; this code is making bad
// assumptions and it's too complicated for me to reason
// about.
Begin = End = SourceLocation();
break;
}
}
// Return the spelling location of the beginning and end of the range.
Begin = SM->getSpellingLoc(Begin);
End = SM->getSpellingLoc(End);
SpellingRanges.push_back(CharSourceRange(SourceRange(Begin, End),
IsTokenRange));
}
}
void DiagnosticRenderer::emitCaret(SourceLocation Loc,
DiagnosticsEngine::Level Level,
ArrayRef<CharSourceRange> Ranges,
ArrayRef<FixItHint> Hints,
const SourceManager &SM) {
SmallVector<CharSourceRange, 4> SpellingRanges;
mapDiagnosticRanges(Loc, Ranges, SpellingRanges, &SM);
emitCodeContext(Loc, Level, SpellingRanges, Hints, SM);
}
/// \brief Recursively emit notes for each macro expansion and caret
/// diagnostics where appropriate.
///
/// Walks up the macro expansion stack printing expansion notes, the code
/// snippet, caret, underlines and FixItHint display as appropriate at each
/// level.
///
/// \param Loc The location for this caret.
/// \param Level The diagnostic level currently being emitted.
/// \param Ranges The underlined ranges for this code snippet.
/// \param Hints The FixIt hints active for this diagnostic.
/// \param OnMacroInst The current depth of the macro expansion stack.
void DiagnosticRenderer::emitMacroExpansions(SourceLocation Loc,
DiagnosticsEngine::Level Level,
ArrayRef<CharSourceRange> Ranges,
ArrayRef<FixItHint> Hints,
const SourceManager &SM,
unsigned &MacroDepth,
unsigned OnMacroInst) {
assert(!Loc.isInvalid() && "must have a valid source location here");
// Walk up to the caller of this macro, and produce a backtrace down to there.
SourceLocation OneLevelUp = SM.getImmediateMacroCallerLoc(Loc);
if (OneLevelUp.isMacroID())
emitMacroExpansions(OneLevelUp, Level, Ranges, Hints, SM,
MacroDepth, OnMacroInst + 1);
else
MacroDepth = OnMacroInst + 1;
unsigned MacroSkipStart = 0, MacroSkipEnd = 0;
if (MacroDepth > DiagOpts->MacroBacktraceLimit &&
DiagOpts->MacroBacktraceLimit != 0) {
MacroSkipStart = DiagOpts->MacroBacktraceLimit / 2 +
DiagOpts->MacroBacktraceLimit % 2;
MacroSkipEnd = MacroDepth - DiagOpts->MacroBacktraceLimit / 2;
}
// Whether to suppress printing this macro expansion.
bool Suppressed = (OnMacroInst >= MacroSkipStart &&
OnMacroInst < MacroSkipEnd);
if (Suppressed) {
// Tell the user that we've skipped contexts.
if (OnMacroInst == MacroSkipStart) {
SmallString<200> MessageStorage;
llvm::raw_svector_ostream Message(MessageStorage);
Message << "(skipping " << (MacroSkipEnd - MacroSkipStart)
<< " expansions in backtrace; use -fmacro-backtrace-limit=0 to "
"see all)";
emitBasicNote(Message.str());
}
return;
}
// Find the spelling location for the macro definition. We must use the
// spelling location here to avoid emitting a macro bactrace for the note.
SourceLocation SpellingLoc = Loc;
// If this is the expansion of a macro argument, point the caret at the
// use of the argument in the definition of the macro, not the expansion.
if (SM.isMacroArgExpansion(Loc))
SpellingLoc = SM.getImmediateExpansionRange(Loc).first;
SpellingLoc = SM.getSpellingLoc(SpellingLoc);
// Map the ranges into the FileID of the diagnostic location.
SmallVector<CharSourceRange, 4> SpellingRanges;
mapDiagnosticRanges(Loc, Ranges, SpellingRanges, &SM);
SmallString<100> MessageStorage;
llvm::raw_svector_ostream Message(MessageStorage);
StringRef MacroName = getImmediateMacroName(Loc, SM, LangOpts);
if (MacroName.empty())
Message << "expanded from here";
else
Message << "expanded from macro '" << MacroName << "'";
emitDiagnostic(SpellingLoc, DiagnosticsEngine::Note, Message.str(),
SpellingRanges, None, &SM);
}
DiagnosticNoteRenderer::~DiagnosticNoteRenderer() {}
void DiagnosticNoteRenderer::emitIncludeLocation(SourceLocation Loc,
PresumedLoc PLoc,
const SourceManager &SM) {
// Generate a note indicating the include location.
SmallString<200> MessageStorage;
llvm::raw_svector_ostream Message(MessageStorage);
Message << "in file included from " << PLoc.getFilename() << ':'
<< PLoc.getLine() << ":";
emitNote(Loc, Message.str(), &SM);
}
void DiagnosticNoteRenderer::emitImportLocation(SourceLocation Loc,
PresumedLoc PLoc,
StringRef ModuleName,
const SourceManager &SM) {
// Generate a note indicating the include location.
SmallString<200> MessageStorage;
llvm::raw_svector_ostream Message(MessageStorage);
Message << "in module '" << ModuleName << "' imported from "
<< PLoc.getFilename() << ':' << PLoc.getLine() << ":";
emitNote(Loc, Message.str(), &SM);
}
void
DiagnosticNoteRenderer::emitBuildingModuleLocation(SourceLocation Loc,
PresumedLoc PLoc,
StringRef ModuleName,
const SourceManager &SM) {
// Generate a note indicating the include location.
SmallString<200> MessageStorage;
llvm::raw_svector_ostream Message(MessageStorage);
if (PLoc.getFilename())
Message << "while building module '" << ModuleName << "' imported from "
<< PLoc.getFilename() << ':' << PLoc.getLine() << ":";
else
Message << "while building module '" << ModuleName << ":";
emitNote(Loc, Message.str(), &SM);
}