Refactor 'TextDiagnostic' to have a parent class 'DiagnosticRenderer' which handles
the policy of how diagnostics are lowered/rendered, while TextDiagnostic handles
the actual pretty-printing.
This is a first part of reworking SerializedDiagnosticPrinter to use the same
inclusion-stack/macro-expansion logic as TextDiagnostic.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146819 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/DiagnosticRenderer.cpp b/lib/Frontend/DiagnosticRenderer.cpp
new file mode 100644
index 0000000..293ffb7
--- /dev/null
+++ b/lib/Frontend/DiagnosticRenderer.cpp
@@ -0,0 +1,297 @@
+//===--- 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/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/DiagnosticOptions.h"
+#include "clang/Lex/Lexer.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/ADT/SmallString.h"
+#include <algorithm>
+using namespace clang;
+
+/// Look through spelling locations for a macro argument expansion, and
+/// if found skip to it so that we can trace the argument rather than the macros
+/// in which that argument is used. If no macro argument expansion is found,
+/// don't skip anything and return the starting location.
+static SourceLocation skipToMacroArgExpansion(const SourceManager &SM,
+ SourceLocation StartLoc) {
+ for (SourceLocation L = StartLoc; L.isMacroID();
+ L = SM.getImmediateSpellingLoc(L)) {
+ if (SM.isMacroArgExpansion(L))
+ return L;
+ }
+
+ // Otherwise just return initial location, there's nothing to skip.
+ return StartLoc;
+}
+
+/// Gets the location of the immediate macro caller, one level up the stack
+/// toward the initial macro typed into the source.
+static SourceLocation getImmediateMacroCallerLoc(const SourceManager &SM,
+ SourceLocation Loc) {
+ if (!Loc.isMacroID()) return Loc;
+
+ // When we have the location of (part of) an expanded parameter, its spelling
+ // location points to the argument as typed into the macro call, and
+ // therefore is used to locate the macro caller.
+ if (SM.isMacroArgExpansion(Loc))
+ return SM.getImmediateSpellingLoc(Loc);
+
+ // Otherwise, the caller of the macro is located where this macro is
+ // expanded (while the spelling is part of the macro definition).
+ return SM.getImmediateExpansionRange(Loc).first;
+}
+
+/// Gets the location of the immediate macro callee, one level down the stack
+/// toward the leaf macro.
+static SourceLocation getImmediateMacroCalleeLoc(const SourceManager &SM,
+ SourceLocation Loc) {
+ if (!Loc.isMacroID()) return Loc;
+
+ // When we have the location of (part of) an expanded parameter, its
+ // expansion location points to the unexpanded paramater reference within
+ // the macro definition (or callee).
+ if (SM.isMacroArgExpansion(Loc))
+ return SM.getImmediateExpansionRange(Loc).first;
+
+ // Otherwise, the callee of the macro is located where this location was
+ // spelled inside the macro definition.
+ return SM.getImmediateSpellingLoc(Loc);
+}
+
+/// \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.
+///
+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;
+
+ // 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);
+}
+
+/// Get the presumed location of a diagnostic message. This computes the
+/// presumed location for the top of any macro backtrace when present.
+static PresumedLoc getDiagnosticPresumedLoc(const SourceManager &SM,
+ SourceLocation Loc) {
+ // This is a condensed form of the algorithm used by emitCaretDiagnostic to
+ // walk to the top of the macro call stack.
+ while (Loc.isMacroID()) {
+ Loc = skipToMacroArgExpansion(SM, Loc);
+ Loc = getImmediateMacroCallerLoc(SM, Loc);
+ }
+
+ return SM.getPresumedLoc(Loc);
+}
+
+DiagnosticRenderer::DiagnosticRenderer(const SourceManager &SM,
+ const LangOptions &LangOpts,
+ const DiagnosticOptions &DiagOpts)
+: SM(SM), LangOpts(LangOpts), DiagOpts(DiagOpts), LastLevel() {}
+
+DiagnosticRenderer::~DiagnosticRenderer() {}
+
+
+void DiagnosticRenderer::emitDiagnostic(SourceLocation Loc,
+ DiagnosticsEngine::Level Level,
+ StringRef Message,
+ ArrayRef<CharSourceRange> Ranges,
+ ArrayRef<FixItHint> FixItHints,
+ const Diagnostic *Info) {
+
+ beginDiagnostic(Info, Level);
+
+ PresumedLoc PLoc = getDiagnosticPresumedLoc(SM, Loc);
+
+ // First, if this diagnostic is not in the main file, print out the
+ // "included from" lines.
+ emitIncludeStack(PLoc.getIncludeLoc(), Level);
+
+ // Next, emit the actual diagnostic message.
+ emitDiagnosticMessage(Loc, PLoc, Level, Message, Ranges, Info);
+
+ // Only recurse if we have a valid location.
+ if (Loc.isValid()) {
+ // Get the ranges into a local array we can hack on.
+ SmallVector<CharSourceRange, 20> MutableRanges(Ranges.begin(),
+ Ranges.end());
+
+ for (ArrayRef<FixItHint>::const_iterator I = FixItHints.begin(),
+ E = FixItHints.end();
+ I != E; ++I)
+ if (I->RemoveRange.isValid())
+ MutableRanges.push_back(I->RemoveRange);
+
+ unsigned MacroDepth = 0;
+ emitMacroExpansionsAndCarets(Loc, Level, MutableRanges, FixItHints,
+ MacroDepth);
+ }
+
+ LastLoc = Loc;
+ LastLevel = Level;
+
+ endDiagnostic(Info, Level);
+}
+
+/// \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 Level The diagnostic level of the message this stack pertains to.
+/// \param Loc The include location of the current file (not the diagnostic
+/// location).
+void DiagnosticRenderer::emitIncludeStack(SourceLocation Loc,
+ DiagnosticsEngine::Level Level) {
+ // Skip redundant include stacks altogether.
+ if (LastIncludeLoc == Loc)
+ return;
+ LastIncludeLoc = Loc;
+
+ if (!DiagOpts.ShowNoteIncludeStack && Level == DiagnosticsEngine::Note)
+ return;
+
+ emitIncludeStackRecursively(Loc);
+}
+
+/// \brief Helper to recursivly walk up the include stack and print each layer
+/// on the way back down.
+void DiagnosticRenderer::emitIncludeStackRecursively(SourceLocation Loc) {
+ if (Loc.isInvalid())
+ return;
+
+ PresumedLoc PLoc = SM.getPresumedLoc(Loc);
+ if (PLoc.isInvalid())
+ return;
+
+ // Emit the other include frames first.
+ emitIncludeStackRecursively(PLoc.getIncludeLoc());
+
+ // Emit the inclusion text/note.
+ emitIncludeLocation(Loc, PLoc);
+}
+
+/// \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 MacroSkipEnd The depth to stop skipping macro expansions.
+/// \param OnMacroInst The current depth of the macro expansion stack.
+void DiagnosticRenderer::emitMacroExpansionsAndCarets(
+ SourceLocation Loc,
+ DiagnosticsEngine::Level Level,
+ SmallVectorImpl<CharSourceRange>& Ranges,
+ ArrayRef<FixItHint> Hints,
+ unsigned &MacroDepth,
+ unsigned OnMacroInst)
+{
+ assert(!Loc.isInvalid() && "must have a valid source location here");
+
+ // If this is a file source location, directly emit the source snippet and
+ // caret line. Also record the macro depth reached.
+ if (Loc.isFileID()) {
+ assert(MacroDepth == 0 && "We shouldn't hit a leaf node twice!");
+ MacroDepth = OnMacroInst;
+ emitCodeContext(Loc, Level, Ranges, Hints);
+ return;
+ }
+ // Otherwise recurse through each macro expansion layer.
+
+ // When processing macros, skip over the expansions leading up to
+ // a macro argument, and trace the argument's expansion stack instead.
+ Loc = skipToMacroArgExpansion(SM, Loc);
+
+ SourceLocation OneLevelUp = getImmediateMacroCallerLoc(SM, Loc);
+
+ // FIXME: Map ranges?
+ emitMacroExpansionsAndCarets(OneLevelUp, Level, Ranges, Hints, MacroDepth,
+ OnMacroInst + 1);
+
+ // Save the original location so we can find the spelling of the macro call.
+ SourceLocation MacroLoc = Loc;
+
+ // Map the location.
+ Loc = getImmediateMacroCalleeLoc(SM, Loc);
+
+ unsigned MacroSkipStart = 0, MacroSkipEnd = 0;
+ if (MacroDepth > DiagOpts.MacroBacktraceLimit) {
+ 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);
+
+ // Map the ranges.
+ for (SmallVectorImpl<CharSourceRange>::iterator I = Ranges.begin(),
+ E = Ranges.end();
+ I != E; ++I) {
+ SourceLocation Start = I->getBegin(), End = I->getEnd();
+ if (Start.isMacroID())
+ I->setBegin(getImmediateMacroCalleeLoc(SM, Start));
+ if (End.isMacroID())
+ I->setEnd(getImmediateMacroCalleeLoc(SM, End));
+ }
+
+ if (Suppressed) {
+ // Tell the user that we've skipped contexts.
+ if (OnMacroInst == MacroSkipStart) {
+ llvm::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;
+ }
+
+ llvm::SmallString<100> MessageStorage;
+ llvm::raw_svector_ostream Message(MessageStorage);
+ Message << "expanded from macro '"
+ << getImmediateMacroName(MacroLoc, SM, LangOpts) << "'";
+ emitDiagnostic(SM.getSpellingLoc(Loc), DiagnosticsEngine::Note,
+ Message.str(),
+ Ranges, ArrayRef<FixItHint>());
+}
+