llvm-project/clang/lib/Frontend/PrintPreprocessedOutput.cpp

1028 lines
37 KiB
C++

//===--- PrintPreprocessedOutput.cpp - Implement the -E mode --------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This code simply runs the preprocessor on the input file and prints out the
// result. This is the traditional behavior of the -E option.
//
//===----------------------------------------------------------------------===//
#include "clang/Frontend/Utils.h"
#include "clang/Basic/CharInfo.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Frontend/PreprocessorOutputOptions.h"
#include "clang/Lex/MacroInfo.h"
#include "clang/Lex/PPCallbacks.h"
#include "clang/Lex/Pragma.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/TokenConcatenation.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <cstdio>
using namespace clang;
/// PrintMacroDefinition - Print a macro definition in a form that will be
/// properly accepted back as a definition.
static void PrintMacroDefinition(const IdentifierInfo &II, const MacroInfo &MI,
Preprocessor &PP, raw_ostream &OS) {
OS << "#define " << II.getName();
if (MI.isFunctionLike()) {
OS << '(';
if (!MI.param_empty()) {
MacroInfo::param_iterator AI = MI.param_begin(), E = MI.param_end();
for (; AI+1 != E; ++AI) {
OS << (*AI)->getName();
OS << ',';
}
// Last argument.
if ((*AI)->getName() == "__VA_ARGS__")
OS << "...";
else
OS << (*AI)->getName();
}
if (MI.isGNUVarargs())
OS << "..."; // #define foo(x...)
OS << ')';
}
// GCC always emits a space, even if the macro body is empty. However, do not
// want to emit two spaces if the first token has a leading space.
if (MI.tokens_empty() || !MI.tokens_begin()->hasLeadingSpace())
OS << ' ';
SmallString<128> SpellingBuffer;
for (const auto &T : MI.tokens()) {
if (T.hasLeadingSpace())
OS << ' ';
OS << PP.getSpelling(T, SpellingBuffer);
}
}
//===----------------------------------------------------------------------===//
// Preprocessed token printer
//===----------------------------------------------------------------------===//
namespace {
class PrintPPOutputPPCallbacks : public PPCallbacks {
Preprocessor &PP;
SourceManager &SM;
TokenConcatenation ConcatInfo;
public:
raw_ostream &OS;
private:
unsigned CurLine;
bool EmittedTokensOnThisLine;
bool EmittedDirectiveOnThisLine;
SrcMgr::CharacteristicKind FileType;
SmallString<512> CurFilename;
bool Initialized;
bool DisableLineMarkers;
bool DumpDefines;
bool DumpIncludeDirectives;
bool UseLineDirectives;
bool IsFirstFileEntered;
bool MinimizeWhitespace;
Token PrevTok;
Token PrevPrevTok;
public:
PrintPPOutputPPCallbacks(Preprocessor &pp, raw_ostream &os, bool lineMarkers,
bool defines, bool DumpIncludeDirectives,
bool UseLineDirectives, bool MinimizeWhitespace)
: PP(pp), SM(PP.getSourceManager()), ConcatInfo(PP), OS(os),
DisableLineMarkers(lineMarkers), DumpDefines(defines),
DumpIncludeDirectives(DumpIncludeDirectives),
UseLineDirectives(UseLineDirectives),
MinimizeWhitespace(MinimizeWhitespace) {
CurLine = 0;
CurFilename += "<uninit>";
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
FileType = SrcMgr::C_User;
Initialized = false;
IsFirstFileEntered = false;
PrevTok.startToken();
PrevPrevTok.startToken();
}
bool isMinimizeWhitespace() const { return MinimizeWhitespace; }
void setEmittedTokensOnThisLine() { EmittedTokensOnThisLine = true; }
bool hasEmittedTokensOnThisLine() const { return EmittedTokensOnThisLine; }
void setEmittedDirectiveOnThisLine() { EmittedDirectiveOnThisLine = true; }
bool hasEmittedDirectiveOnThisLine() const {
return EmittedDirectiveOnThisLine;
}
/// Ensure that the output stream position is at the beginning of a new line
/// and inserts one if it does not. It is intended to ensure that directives
/// inserted by the directives not from the input source (such as #line) are
/// in the first column. To insert newlines that represent the input, use
/// MoveToLine(/*...*/, /*RequireStartOfLine=*/true).
void startNewLineIfNeeded();
void FileChanged(SourceLocation Loc, FileChangeReason Reason,
SrcMgr::CharacteristicKind FileType,
FileID PrevFID) override;
void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
StringRef FileName, bool IsAngled,
CharSourceRange FilenameRange, const FileEntry *File,
StringRef SearchPath, StringRef RelativePath,
const Module *Imported,
SrcMgr::CharacteristicKind FileType) override;
void Ident(SourceLocation Loc, StringRef str) override;
void PragmaMessage(SourceLocation Loc, StringRef Namespace,
PragmaMessageKind Kind, StringRef Str) override;
void PragmaDebug(SourceLocation Loc, StringRef DebugType) override;
void PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) override;
void PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) override;
void PragmaDiagnostic(SourceLocation Loc, StringRef Namespace,
diag::Severity Map, StringRef Str) override;
void PragmaWarning(SourceLocation Loc, PragmaWarningSpecifier WarningSpec,
ArrayRef<int> Ids) override;
void PragmaWarningPush(SourceLocation Loc, int Level) override;
void PragmaWarningPop(SourceLocation Loc) override;
void PragmaExecCharsetPush(SourceLocation Loc, StringRef Str) override;
void PragmaExecCharsetPop(SourceLocation Loc) override;
void PragmaAssumeNonNullBegin(SourceLocation Loc) override;
void PragmaAssumeNonNullEnd(SourceLocation Loc) override;
/// Insert whitespace before emitting the next token.
///
/// @param Tok Next token to be emitted.
/// @param RequireSpace Ensure at least one whitespace is emitted. Useful
/// if non-tokens have been emitted to the stream.
/// @param RequireSameLine Never emit newlines. Useful when semantics depend
/// on being on the same line, such as directives.
void HandleWhitespaceBeforeTok(const Token &Tok, bool RequireSpace,
bool RequireSameLine);
/// Move to the line of the provided source location. This will
/// return true if a newline was inserted or if
/// the requested location is the first token on the first line.
/// In these cases the next output will be the first column on the line and
/// make it possible to insert indention. The newline was inserted
/// implicitly when at the beginning of the file.
///
/// @param Tok Token where to move to.
/// @param RequireStartOfLine Whether the next line depends on being in the
/// first column, such as a directive.
///
/// @return Whether column adjustments are necessary.
bool MoveToLine(const Token &Tok, bool RequireStartOfLine) {
PresumedLoc PLoc = SM.getPresumedLoc(Tok.getLocation());
unsigned TargetLine = PLoc.isValid() ? PLoc.getLine() : CurLine;
bool IsFirstInFile =
Tok.isAtStartOfLine() && PLoc.isValid() && PLoc.getLine() == 1;
return MoveToLine(TargetLine, RequireStartOfLine) || IsFirstInFile;
}
/// Move to the line of the provided source location. Returns true if a new
/// line was inserted.
bool MoveToLine(SourceLocation Loc, bool RequireStartOfLine) {
PresumedLoc PLoc = SM.getPresumedLoc(Loc);
unsigned TargetLine = PLoc.isValid() ? PLoc.getLine() : CurLine;
return MoveToLine(TargetLine, RequireStartOfLine);
}
bool MoveToLine(unsigned LineNo, bool RequireStartOfLine);
bool AvoidConcat(const Token &PrevPrevTok, const Token &PrevTok,
const Token &Tok) {
return ConcatInfo.AvoidConcat(PrevPrevTok, PrevTok, Tok);
}
void WriteLineInfo(unsigned LineNo, const char *Extra=nullptr,
unsigned ExtraLen=0);
bool LineMarkersAreDisabled() const { return DisableLineMarkers; }
void HandleNewlinesInToken(const char *TokStr, unsigned Len);
/// MacroDefined - This hook is called whenever a macro definition is seen.
void MacroDefined(const Token &MacroNameTok,
const MacroDirective *MD) override;
/// MacroUndefined - This hook is called whenever a macro #undef is seen.
void MacroUndefined(const Token &MacroNameTok,
const MacroDefinition &MD,
const MacroDirective *Undef) override;
void BeginModule(const Module *M);
void EndModule(const Module *M);
};
} // end anonymous namespace
void PrintPPOutputPPCallbacks::WriteLineInfo(unsigned LineNo,
const char *Extra,
unsigned ExtraLen) {
startNewLineIfNeeded();
// Emit #line directives or GNU line markers depending on what mode we're in.
if (UseLineDirectives) {
OS << "#line" << ' ' << LineNo << ' ' << '"';
OS.write_escaped(CurFilename);
OS << '"';
} else {
OS << '#' << ' ' << LineNo << ' ' << '"';
OS.write_escaped(CurFilename);
OS << '"';
if (ExtraLen)
OS.write(Extra, ExtraLen);
if (FileType == SrcMgr::C_System)
OS.write(" 3", 2);
else if (FileType == SrcMgr::C_ExternCSystem)
OS.write(" 3 4", 4);
}
OS << '\n';
}
/// MoveToLine - Move the output to the source line specified by the location
/// object. We can do this by emitting some number of \n's, or be emitting a
/// #line directive. This returns false if already at the specified line, true
/// if some newlines were emitted.
bool PrintPPOutputPPCallbacks::MoveToLine(unsigned LineNo,
bool RequireStartOfLine) {
// If it is required to start a new line or finish the current, insert
// vertical whitespace now and take it into account when moving to the
// expected line.
bool StartedNewLine = false;
if ((RequireStartOfLine && EmittedTokensOnThisLine) ||
EmittedDirectiveOnThisLine) {
OS << '\n';
StartedNewLine = true;
CurLine += 1;
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
}
// If this line is "close enough" to the original line, just print newlines,
// otherwise print a #line directive.
if (CurLine == LineNo) {
// Nothing to do if we are already on the correct line.
} else if (MinimizeWhitespace && DisableLineMarkers) {
// With -E -P -fminimize-whitespace, don't emit anything if not necessary.
} else if (!StartedNewLine && LineNo - CurLine == 1) {
// Printing a single line has priority over printing a #line directive, even
// when minimizing whitespace which otherwise would print #line directives
// for every single line.
OS << '\n';
StartedNewLine = true;
} else if (!DisableLineMarkers) {
if (LineNo - CurLine <= 8) {
const char *NewLines = "\n\n\n\n\n\n\n\n";
OS.write(NewLines, LineNo - CurLine);
} else {
// Emit a #line or line marker.
WriteLineInfo(LineNo, nullptr, 0);
}
StartedNewLine = true;
} else if (EmittedTokensOnThisLine) {
// If we are not on the correct line and don't need to be line-correct,
// at least ensure we start on a new line.
OS << '\n';
StartedNewLine = true;
}
if (StartedNewLine) {
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
}
CurLine = LineNo;
return StartedNewLine;
}
void PrintPPOutputPPCallbacks::startNewLineIfNeeded() {
if (EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) {
OS << '\n';
EmittedTokensOnThisLine = false;
EmittedDirectiveOnThisLine = false;
}
}
/// FileChanged - Whenever the preprocessor enters or exits a #include file
/// it invokes this handler. Update our conception of the current source
/// position.
void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,
FileChangeReason Reason,
SrcMgr::CharacteristicKind NewFileType,
FileID PrevFID) {
// Unless we are exiting a #include, make sure to skip ahead to the line the
// #include directive was at.
SourceManager &SourceMgr = SM;
PresumedLoc UserLoc = SourceMgr.getPresumedLoc(Loc);
if (UserLoc.isInvalid())
return;
unsigned NewLine = UserLoc.getLine();
if (Reason == PPCallbacks::EnterFile) {
SourceLocation IncludeLoc = UserLoc.getIncludeLoc();
if (IncludeLoc.isValid())
MoveToLine(IncludeLoc, /*RequireStartOfLine=*/false);
} else if (Reason == PPCallbacks::SystemHeaderPragma) {
// GCC emits the # directive for this directive on the line AFTER the
// directive and emits a bunch of spaces that aren't needed. This is because
// otherwise we will emit a line marker for THIS line, which requires an
// extra blank line after the directive to avoid making all following lines
// off by one. We can do better by simply incrementing NewLine here.
NewLine += 1;
}
CurLine = NewLine;
CurFilename.clear();
CurFilename += UserLoc.getFilename();
FileType = NewFileType;
if (DisableLineMarkers) {
if (!MinimizeWhitespace)
startNewLineIfNeeded();
return;
}
if (!Initialized) {
WriteLineInfo(CurLine);
Initialized = true;
}
// Do not emit an enter marker for the main file (which we expect is the first
// entered file). This matches gcc, and improves compatibility with some tools
// which track the # line markers as a way to determine when the preprocessed
// output is in the context of the main file.
if (Reason == PPCallbacks::EnterFile && !IsFirstFileEntered) {
IsFirstFileEntered = true;
return;
}
switch (Reason) {
case PPCallbacks::EnterFile:
WriteLineInfo(CurLine, " 1", 2);
break;
case PPCallbacks::ExitFile:
WriteLineInfo(CurLine, " 2", 2);
break;
case PPCallbacks::SystemHeaderPragma:
case PPCallbacks::RenameFile:
WriteLineInfo(CurLine);
break;
}
}
void PrintPPOutputPPCallbacks::InclusionDirective(
SourceLocation HashLoc,
const Token &IncludeTok,
StringRef FileName,
bool IsAngled,
CharSourceRange FilenameRange,
const FileEntry *File,
StringRef SearchPath,
StringRef RelativePath,
const Module *Imported,
SrcMgr::CharacteristicKind FileType) {
// In -dI mode, dump #include directives prior to dumping their content or
// interpretation.
if (DumpIncludeDirectives) {
MoveToLine(HashLoc, /*RequireStartOfLine=*/true);
const std::string TokenText = PP.getSpelling(IncludeTok);
assert(!TokenText.empty());
OS << "#" << TokenText << " "
<< (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
<< " /* clang -E -dI */";
setEmittedDirectiveOnThisLine();
}
// When preprocessing, turn implicit imports into module import pragmas.
if (Imported) {
switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {
case tok::pp_include:
case tok::pp_import:
case tok::pp_include_next:
MoveToLine(HashLoc, /*RequireStartOfLine=*/true);
OS << "#pragma clang module import " << Imported->getFullModuleName(true)
<< " /* clang -E: implicit import for "
<< "#" << PP.getSpelling(IncludeTok) << " "
<< (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')
<< " */";
setEmittedDirectiveOnThisLine();
break;
case tok::pp___include_macros:
// #__include_macros has no effect on a user of a preprocessed source
// file; the only effect is on preprocessing.
//
// FIXME: That's not *quite* true: it causes the module in question to
// be loaded, which can affect downstream diagnostics.
break;
default:
llvm_unreachable("unknown include directive kind");
break;
}
}
}
/// Handle entering the scope of a module during a module compilation.
void PrintPPOutputPPCallbacks::BeginModule(const Module *M) {
startNewLineIfNeeded();
OS << "#pragma clang module begin " << M->getFullModuleName(true);
setEmittedDirectiveOnThisLine();
}
/// Handle leaving the scope of a module during a module compilation.
void PrintPPOutputPPCallbacks::EndModule(const Module *M) {
startNewLineIfNeeded();
OS << "#pragma clang module end /*" << M->getFullModuleName(true) << "*/";
setEmittedDirectiveOnThisLine();
}
/// Ident - Handle #ident directives when read by the preprocessor.
///
void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, StringRef S) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS.write("#ident ", strlen("#ident "));
OS.write(S.begin(), S.size());
setEmittedTokensOnThisLine();
}
/// MacroDefined - This hook is called whenever a macro definition is seen.
void PrintPPOutputPPCallbacks::MacroDefined(const Token &MacroNameTok,
const MacroDirective *MD) {
const MacroInfo *MI = MD->getMacroInfo();
// Only print out macro definitions in -dD mode.
if (!DumpDefines ||
// Ignore __FILE__ etc.
MI->isBuiltinMacro()) return;
MoveToLine(MI->getDefinitionLoc(), /*RequireStartOfLine=*/true);
PrintMacroDefinition(*MacroNameTok.getIdentifierInfo(), *MI, PP, OS);
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::MacroUndefined(const Token &MacroNameTok,
const MacroDefinition &MD,
const MacroDirective *Undef) {
// Only print out macro definitions in -dD mode.
if (!DumpDefines) return;
MoveToLine(MacroNameTok.getLocation(), /*RequireStartOfLine=*/true);
OS << "#undef " << MacroNameTok.getIdentifierInfo()->getName();
setEmittedDirectiveOnThisLine();
}
static void outputPrintable(raw_ostream &OS, StringRef Str) {
for (unsigned char Char : Str) {
if (isPrintable(Char) && Char != '\\' && Char != '"')
OS << (char)Char;
else // Output anything hard as an octal escape.
OS << '\\'
<< (char)('0' + ((Char >> 6) & 7))
<< (char)('0' + ((Char >> 3) & 7))
<< (char)('0' + ((Char >> 0) & 7));
}
}
void PrintPPOutputPPCallbacks::PragmaMessage(SourceLocation Loc,
StringRef Namespace,
PragmaMessageKind Kind,
StringRef Str) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma ";
if (!Namespace.empty())
OS << Namespace << ' ';
switch (Kind) {
case PMK_Message:
OS << "message(\"";
break;
case PMK_Warning:
OS << "warning \"";
break;
case PMK_Error:
OS << "error \"";
break;
}
outputPrintable(OS, Str);
OS << '"';
if (Kind == PMK_Message)
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaDebug(SourceLocation Loc,
StringRef DebugType) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma clang __debug ";
OS << DebugType;
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma " << Namespace << " diagnostic push";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma " << Namespace << " diagnostic pop";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaDiagnostic(SourceLocation Loc,
StringRef Namespace,
diag::Severity Map,
StringRef Str) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma " << Namespace << " diagnostic ";
switch (Map) {
case diag::Severity::Remark:
OS << "remark";
break;
case diag::Severity::Warning:
OS << "warning";
break;
case diag::Severity::Error:
OS << "error";
break;
case diag::Severity::Ignored:
OS << "ignored";
break;
case diag::Severity::Fatal:
OS << "fatal";
break;
}
OS << " \"" << Str << '"';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaWarning(SourceLocation Loc,
PragmaWarningSpecifier WarningSpec,
ArrayRef<int> Ids) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma warning(";
switch(WarningSpec) {
case PWS_Default: OS << "default"; break;
case PWS_Disable: OS << "disable"; break;
case PWS_Error: OS << "error"; break;
case PWS_Once: OS << "once"; break;
case PWS_Suppress: OS << "suppress"; break;
case PWS_Level1: OS << '1'; break;
case PWS_Level2: OS << '2'; break;
case PWS_Level3: OS << '3'; break;
case PWS_Level4: OS << '4'; break;
}
OS << ':';
for (ArrayRef<int>::iterator I = Ids.begin(), E = Ids.end(); I != E; ++I)
OS << ' ' << *I;
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaWarningPush(SourceLocation Loc,
int Level) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma warning(push";
if (Level >= 0)
OS << ", " << Level;
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaWarningPop(SourceLocation Loc) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma warning(pop)";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaExecCharsetPush(SourceLocation Loc,
StringRef Str) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma character_execution_set(push";
if (!Str.empty())
OS << ", " << Str;
OS << ')';
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::PragmaExecCharsetPop(SourceLocation Loc) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma character_execution_set(pop)";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaAssumeNonNullBegin(SourceLocation Loc) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma clang assume_nonnull begin";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::
PragmaAssumeNonNullEnd(SourceLocation Loc) {
MoveToLine(Loc, /*RequireStartOfLine=*/true);
OS << "#pragma clang assume_nonnull end";
setEmittedDirectiveOnThisLine();
}
void PrintPPOutputPPCallbacks::HandleWhitespaceBeforeTok(const Token &Tok,
bool RequireSpace,
bool RequireSameLine) {
// These tokens are not expanded to anything and don't need whitespace before
// them.
if (Tok.is(tok::eof) ||
(Tok.isAnnotation() && !Tok.is(tok::annot_header_unit) &&
!Tok.is(tok::annot_module_begin) && !Tok.is(tok::annot_module_end)))
return;
// EmittedDirectiveOnThisLine takes priority over RequireSameLine.
if ((!RequireSameLine || EmittedDirectiveOnThisLine) &&
MoveToLine(Tok, /*RequireStartOfLine=*/EmittedDirectiveOnThisLine)) {
if (MinimizeWhitespace) {
// Avoid interpreting hash as a directive under -fpreprocessed.
if (Tok.is(tok::hash))
OS << ' ';
} else {
// Print out space characters so that the first token on a line is
// indented for easy reading.
unsigned ColNo = SM.getExpansionColumnNumber(Tok.getLocation());
// The first token on a line can have a column number of 1, yet still
// expect leading white space, if a macro expansion in column 1 starts
// with an empty macro argument, or an empty nested macro expansion. In
// this case, move the token to column 2.
if (ColNo == 1 && Tok.hasLeadingSpace())
ColNo = 2;
// This hack prevents stuff like:
// #define HASH #
// HASH define foo bar
// From having the # character end up at column 1, which makes it so it
// is not handled as a #define next time through the preprocessor if in
// -fpreprocessed mode.
if (ColNo <= 1 && Tok.is(tok::hash))
OS << ' ';
// Otherwise, indent the appropriate number of spaces.
for (; ColNo > 1; --ColNo)
OS << ' ';
}
} else {
// Insert whitespace between the previous and next token if either
// - The caller requires it
// - The input had whitespace between them and we are not in
// whitespace-minimization mode
// - The whitespace is necessary to keep the tokens apart and there is not
// already a newline between them
if (RequireSpace || (!MinimizeWhitespace && Tok.hasLeadingSpace()) ||
((EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) &&
AvoidConcat(PrevPrevTok, PrevTok, Tok)))
OS << ' ';
}
PrevPrevTok = PrevTok;
PrevTok = Tok;
}
void PrintPPOutputPPCallbacks::HandleNewlinesInToken(const char *TokStr,
unsigned Len) {
unsigned NumNewlines = 0;
for (; Len; --Len, ++TokStr) {
if (*TokStr != '\n' &&
*TokStr != '\r')
continue;
++NumNewlines;
// If we have \n\r or \r\n, skip both and count as one line.
if (Len != 1 &&
(TokStr[1] == '\n' || TokStr[1] == '\r') &&
TokStr[0] != TokStr[1]) {
++TokStr;
--Len;
}
}
if (NumNewlines == 0) return;
CurLine += NumNewlines;
}
namespace {
struct UnknownPragmaHandler : public PragmaHandler {
const char *Prefix;
PrintPPOutputPPCallbacks *Callbacks;
// Set to true if tokens should be expanded
bool ShouldExpandTokens;
UnknownPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks,
bool RequireTokenExpansion)
: Prefix(prefix), Callbacks(callbacks),
ShouldExpandTokens(RequireTokenExpansion) {}
void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,
Token &PragmaTok) override {
// Figure out what line we went to and insert the appropriate number of
// newline characters.
Callbacks->MoveToLine(PragmaTok.getLocation(), /*RequireStartOfLine=*/true);
Callbacks->OS.write(Prefix, strlen(Prefix));
Callbacks->setEmittedTokensOnThisLine();
if (ShouldExpandTokens) {
// The first token does not have expanded macros. Expand them, if
// required.
auto Toks = std::make_unique<Token[]>(1);
Toks[0] = PragmaTok;
PP.EnterTokenStream(std::move(Toks), /*NumToks=*/1,
/*DisableMacroExpansion=*/false,
/*IsReinject=*/false);
PP.Lex(PragmaTok);
}
// Read and print all of the pragma tokens.
bool IsFirst = true;
while (PragmaTok.isNot(tok::eod)) {
Callbacks->HandleWhitespaceBeforeTok(PragmaTok, /*RequireSpace=*/IsFirst,
/*RequireSameLine=*/true);
IsFirst = false;
std::string TokSpell = PP.getSpelling(PragmaTok);
Callbacks->OS.write(&TokSpell[0], TokSpell.size());
Callbacks->setEmittedTokensOnThisLine();
if (ShouldExpandTokens)
PP.Lex(PragmaTok);
else
PP.LexUnexpandedToken(PragmaTok);
}
Callbacks->setEmittedDirectiveOnThisLine();
}
};
} // end anonymous namespace
static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok,
PrintPPOutputPPCallbacks *Callbacks,
raw_ostream &OS) {
bool DropComments = PP.getLangOpts().TraditionalCPP &&
!PP.getCommentRetentionState();
bool IsStartOfLine = false;
char Buffer[256];
while (true) {
// Two lines joined with line continuation ('\' as last character on the
// line) must be emitted as one line even though Tok.getLine() returns two
// different values. In this situation Tok.isAtStartOfLine() is false even
// though it may be the first token on the lexical line. When
// dropping/skipping a token that is at the start of a line, propagate the
// start-of-line-ness to the next token to not append it to the previous
// line.
IsStartOfLine = IsStartOfLine || Tok.isAtStartOfLine();
Callbacks->HandleWhitespaceBeforeTok(Tok, /*RequireSpace=*/false,
/*RequireSameLine=*/!IsStartOfLine);
if (DropComments && Tok.is(tok::comment)) {
// Skip comments. Normally the preprocessor does not generate
// tok::comment nodes at all when not keeping comments, but under
// -traditional-cpp the lexer keeps /all/ whitespace, including comments.
PP.Lex(Tok);
continue;
} else if (Tok.is(tok::eod)) {
// Don't print end of directive tokens, since they are typically newlines
// that mess up our line tracking. These come from unknown pre-processor
// directives or hash-prefixed comments in standalone assembly files.
PP.Lex(Tok);
// FIXME: The token on the next line after #include should have
// Tok.isAtStartOfLine() set.
IsStartOfLine = true;
continue;
} else if (Tok.is(tok::annot_module_include)) {
// PrintPPOutputPPCallbacks::InclusionDirective handles producing
// appropriate output here. Ignore this token entirely.
PP.Lex(Tok);
IsStartOfLine = true;
continue;
} else if (Tok.is(tok::annot_module_begin)) {
// FIXME: We retrieve this token after the FileChanged callback, and
// retrieve the module_end token before the FileChanged callback, so
// we render this within the file and render the module end outside the
// file, but this is backwards from the token locations: the module_begin
// token is at the include location (outside the file) and the module_end
// token is at the EOF location (within the file).
Callbacks->BeginModule(
reinterpret_cast<Module *>(Tok.getAnnotationValue()));
PP.Lex(Tok);
IsStartOfLine = true;
continue;
} else if (Tok.is(tok::annot_module_end)) {
Callbacks->EndModule(
reinterpret_cast<Module *>(Tok.getAnnotationValue()));
PP.Lex(Tok);
IsStartOfLine = true;
continue;
} else if (Tok.is(tok::annot_header_unit)) {
// This is a header-name that has been (effectively) converted into a
// module-name.
// FIXME: The module name could contain non-identifier module name
// components. We don't have a good way to round-trip those.
Module *M = reinterpret_cast<Module *>(Tok.getAnnotationValue());
std::string Name = M->getFullModuleName();
OS.write(Name.data(), Name.size());
Callbacks->HandleNewlinesInToken(Name.data(), Name.size());
} else if (Tok.isAnnotation()) {
// Ignore annotation tokens created by pragmas - the pragmas themselves
// will be reproduced in the preprocessed output.
PP.Lex(Tok);
continue;
} else if (IdentifierInfo *II = Tok.getIdentifierInfo()) {
OS << II->getName();
} else if (Tok.isLiteral() && !Tok.needsCleaning() &&
Tok.getLiteralData()) {
OS.write(Tok.getLiteralData(), Tok.getLength());
} else if (Tok.getLength() < llvm::array_lengthof(Buffer)) {
const char *TokPtr = Buffer;
unsigned Len = PP.getSpelling(Tok, TokPtr);
OS.write(TokPtr, Len);
// Tokens that can contain embedded newlines need to adjust our current
// line number.
// FIXME: The token may end with a newline in which case
// setEmittedDirectiveOnThisLine/setEmittedTokensOnThisLine afterwards is
// wrong.
if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
Callbacks->HandleNewlinesInToken(TokPtr, Len);
if (Tok.is(tok::comment) && Len >= 2 && TokPtr[0] == '/' &&
TokPtr[1] == '/') {
// It's a line comment;
// Ensure that we don't concatenate anything behind it.
Callbacks->setEmittedDirectiveOnThisLine();
}
} else {
std::string S = PP.getSpelling(Tok);
OS.write(S.data(), S.size());
// Tokens that can contain embedded newlines need to adjust our current
// line number.
if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)
Callbacks->HandleNewlinesInToken(S.data(), S.size());
if (Tok.is(tok::comment) && S.size() >= 2 && S[0] == '/' && S[1] == '/') {
// It's a line comment;
// Ensure that we don't concatenate anything behind it.
Callbacks->setEmittedDirectiveOnThisLine();
}
}
Callbacks->setEmittedTokensOnThisLine();
IsStartOfLine = false;
if (Tok.is(tok::eof)) break;
PP.Lex(Tok);
}
}
typedef std::pair<const IdentifierInfo *, MacroInfo *> id_macro_pair;
static int MacroIDCompare(const id_macro_pair *LHS, const id_macro_pair *RHS) {
return LHS->first->getName().compare(RHS->first->getName());
}
static void DoPrintMacros(Preprocessor &PP, raw_ostream *OS) {
// Ignore unknown pragmas.
PP.IgnorePragmas();
// -dM mode just scans and ignores all tokens in the files, then dumps out
// the macro table at the end.
PP.EnterMainSourceFile();
Token Tok;
do PP.Lex(Tok);
while (Tok.isNot(tok::eof));
SmallVector<id_macro_pair, 128> MacrosByID;
for (Preprocessor::macro_iterator I = PP.macro_begin(), E = PP.macro_end();
I != E; ++I) {
auto *MD = I->second.getLatest();
if (MD && MD->isDefined())
MacrosByID.push_back(id_macro_pair(I->first, MD->getMacroInfo()));
}
llvm::array_pod_sort(MacrosByID.begin(), MacrosByID.end(), MacroIDCompare);
for (unsigned i = 0, e = MacrosByID.size(); i != e; ++i) {
MacroInfo &MI = *MacrosByID[i].second;
// Ignore computed macros like __LINE__ and friends.
if (MI.isBuiltinMacro()) continue;
PrintMacroDefinition(*MacrosByID[i].first, MI, PP, *OS);
*OS << '\n';
}
}
/// DoPrintPreprocessedInput - This implements -E mode.
///
void clang::DoPrintPreprocessedInput(Preprocessor &PP, raw_ostream *OS,
const PreprocessorOutputOptions &Opts) {
// Show macros with no output is handled specially.
if (!Opts.ShowCPP) {
assert(Opts.ShowMacros && "Not yet implemented!");
DoPrintMacros(PP, OS);
return;
}
// Inform the preprocessor whether we want it to retain comments or not, due
// to -C or -CC.
PP.SetCommentRetentionState(Opts.ShowComments, Opts.ShowMacroComments);
PrintPPOutputPPCallbacks *Callbacks = new PrintPPOutputPPCallbacks(
PP, *OS, !Opts.ShowLineMarkers, Opts.ShowMacros,
Opts.ShowIncludeDirectives, Opts.UseLineDirectives,
Opts.MinimizeWhitespace);
// Expand macros in pragmas with -fms-extensions. The assumption is that
// the majority of pragmas in such a file will be Microsoft pragmas.
// Remember the handlers we will add so that we can remove them later.
std::unique_ptr<UnknownPragmaHandler> MicrosoftExtHandler(
new UnknownPragmaHandler(
"#pragma", Callbacks,
/*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
std::unique_ptr<UnknownPragmaHandler> GCCHandler(new UnknownPragmaHandler(
"#pragma GCC", Callbacks,
/*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
std::unique_ptr<UnknownPragmaHandler> ClangHandler(new UnknownPragmaHandler(
"#pragma clang", Callbacks,
/*RequireTokenExpansion=*/PP.getLangOpts().MicrosoftExt));
PP.AddPragmaHandler(MicrosoftExtHandler.get());
PP.AddPragmaHandler("GCC", GCCHandler.get());
PP.AddPragmaHandler("clang", ClangHandler.get());
// The tokens after pragma omp need to be expanded.
//
// OpenMP [2.1, Directive format]
// Preprocessing tokens following the #pragma omp are subject to macro
// replacement.
std::unique_ptr<UnknownPragmaHandler> OpenMPHandler(
new UnknownPragmaHandler("#pragma omp", Callbacks,
/*RequireTokenExpansion=*/true));
PP.AddPragmaHandler("omp", OpenMPHandler.get());
PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(Callbacks));
// After we have configured the preprocessor, enter the main file.
PP.EnterMainSourceFile();
// Consume all of the tokens that come from the predefines buffer. Those
// should not be emitted into the output and are guaranteed to be at the
// start.
const SourceManager &SourceMgr = PP.getSourceManager();
Token Tok;
do {
PP.Lex(Tok);
if (Tok.is(tok::eof) || !Tok.getLocation().isFileID())
break;
PresumedLoc PLoc = SourceMgr.getPresumedLoc(Tok.getLocation());
if (PLoc.isInvalid())
break;
if (strcmp(PLoc.getFilename(), "<built-in>"))
break;
} while (true);
// Read all the preprocessed tokens, printing them out to the stream.
PrintPreprocessedTokens(PP, Tok, Callbacks, *OS);
*OS << '\n';
// Remove the handlers we just added to leave the preprocessor in a sane state
// so that it can be reused (for example by a clang::Parser instance).
PP.RemovePragmaHandler(MicrosoftExtHandler.get());
PP.RemovePragmaHandler("GCC", GCCHandler.get());
PP.RemovePragmaHandler("clang", ClangHandler.get());
PP.RemovePragmaHandler("omp", OpenMPHandler.get());
}