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Diffstat (limited to 'clang/lib/Lex/PPMacroExpansion.cpp')
-rw-r--r-- | clang/lib/Lex/PPMacroExpansion.cpp | 530 |
1 files changed, 0 insertions, 530 deletions
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp deleted file mode 100644 index fb9b613..0000000 --- a/clang/lib/Lex/PPMacroExpansion.cpp +++ /dev/null @@ -1,530 +0,0 @@ -//===--- MacroExpansion.cpp - Top level Macro Expansion -------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the top level handling of macro expasion for the -// preprocessor. -// -//===----------------------------------------------------------------------===// - -#include "clang/Lex/Preprocessor.h" -#include "MacroArgs.h" -#include "clang/Lex/MacroInfo.h" -#include "clang/Basic/SourceManager.h" -#include "clang/Basic/FileManager.h" -#include "clang/Basic/Diagnostic.h" -#include <ctime> -using namespace clang; - -/// setMacroInfo - Specify a macro for this identifier. -/// -void Preprocessor::setMacroInfo(IdentifierInfo *II, MacroInfo *MI) { - if (MI == 0) { - if (II->hasMacroDefinition()) { - Macros.erase(II); - II->setHasMacroDefinition(false); - } - } else { - Macros[II] = MI; - II->setHasMacroDefinition(true); - } -} - -/// RegisterBuiltinMacro - Register the specified identifier in the identifier -/// table and mark it as a builtin macro to be expanded. -IdentifierInfo *Preprocessor::RegisterBuiltinMacro(const char *Name) { - // Get the identifier. - IdentifierInfo *Id = getIdentifierInfo(Name); - - // Mark it as being a macro that is builtin. - MacroInfo *MI = new MacroInfo(SourceLocation()); - MI->setIsBuiltinMacro(); - setMacroInfo(Id, MI); - return Id; -} - - -/// RegisterBuiltinMacros - Register builtin macros, such as __LINE__ with the -/// identifier table. -void Preprocessor::RegisterBuiltinMacros() { - Ident__LINE__ = RegisterBuiltinMacro("__LINE__"); - Ident__FILE__ = RegisterBuiltinMacro("__FILE__"); - Ident__DATE__ = RegisterBuiltinMacro("__DATE__"); - Ident__TIME__ = RegisterBuiltinMacro("__TIME__"); - Ident_Pragma = RegisterBuiltinMacro("_Pragma"); - - // GCC Extensions. - Ident__BASE_FILE__ = RegisterBuiltinMacro("__BASE_FILE__"); - Ident__INCLUDE_LEVEL__ = RegisterBuiltinMacro("__INCLUDE_LEVEL__"); - Ident__TIMESTAMP__ = RegisterBuiltinMacro("__TIMESTAMP__"); -} - -/// isTrivialSingleTokenExpansion - Return true if MI, which has a single token -/// in its expansion, currently expands to that token literally. -static bool isTrivialSingleTokenExpansion(const MacroInfo *MI, - const IdentifierInfo *MacroIdent, - Preprocessor &PP) { - IdentifierInfo *II = MI->getReplacementToken(0).getIdentifierInfo(); - - // If the token isn't an identifier, it's always literally expanded. - if (II == 0) return true; - - // If the identifier is a macro, and if that macro is enabled, it may be - // expanded so it's not a trivial expansion. - if (II->hasMacroDefinition() && PP.getMacroInfo(II)->isEnabled() && - // Fast expanding "#define X X" is ok, because X would be disabled. - II != MacroIdent) - return false; - - // If this is an object-like macro invocation, it is safe to trivially expand - // it. - if (MI->isObjectLike()) return true; - - // If this is a function-like macro invocation, it's safe to trivially expand - // as long as the identifier is not a macro argument. - for (MacroInfo::arg_iterator I = MI->arg_begin(), E = MI->arg_end(); - I != E; ++I) - if (*I == II) - return false; // Identifier is a macro argument. - - return true; -} - - -/// isNextPPTokenLParen - Determine whether the next preprocessor token to be -/// lexed is a '('. If so, consume the token and return true, if not, this -/// method should have no observable side-effect on the lexed tokens. -bool Preprocessor::isNextPPTokenLParen() { - // Do some quick tests for rejection cases. - unsigned Val; - if (CurLexer) - Val = CurLexer->isNextPPTokenLParen(); - else - Val = CurTokenLexer->isNextTokenLParen(); - - if (Val == 2) { - // We have run off the end. If it's a source file we don't - // examine enclosing ones (C99 5.1.1.2p4). Otherwise walk up the - // macro stack. - if (CurLexer) - return false; - for (unsigned i = IncludeMacroStack.size(); i != 0; --i) { - IncludeStackInfo &Entry = IncludeMacroStack[i-1]; - if (Entry.TheLexer) - Val = Entry.TheLexer->isNextPPTokenLParen(); - else - Val = Entry.TheTokenLexer->isNextTokenLParen(); - - if (Val != 2) - break; - - // Ran off the end of a source file? - if (Entry.TheLexer) - return false; - } - } - - // Okay, if we know that the token is a '(', lex it and return. Otherwise we - // have found something that isn't a '(' or we found the end of the - // translation unit. In either case, return false. - if (Val != 1) - return false; - - Token Tok; - LexUnexpandedToken(Tok); - assert(Tok.is(tok::l_paren) && "Error computing l-paren-ness?"); - return true; -} - -/// HandleMacroExpandedIdentifier - If an identifier token is read that is to be -/// expanded as a macro, handle it and return the next token as 'Identifier'. -bool Preprocessor::HandleMacroExpandedIdentifier(Token &Identifier, - MacroInfo *MI) { - // If this is a macro exapnsion in the "#if !defined(x)" line for the file, - // then the macro could expand to different things in other contexts, we need - // to disable the optimization in this case. - if (CurLexer) CurLexer->MIOpt.ExpandedMacro(); - - // If this is a builtin macro, like __LINE__ or _Pragma, handle it specially. - if (MI->isBuiltinMacro()) { - ExpandBuiltinMacro(Identifier); - return false; - } - - /// Args - If this is a function-like macro expansion, this contains, - /// for each macro argument, the list of tokens that were provided to the - /// invocation. - MacroArgs *Args = 0; - - // If this is a function-like macro, read the arguments. - if (MI->isFunctionLike()) { - // C99 6.10.3p10: If the preprocessing token immediately after the the macro - // name isn't a '(', this macro should not be expanded. Otherwise, consume - // it. - if (!isNextPPTokenLParen()) - return true; - - // Remember that we are now parsing the arguments to a macro invocation. - // Preprocessor directives used inside macro arguments are not portable, and - // this enables the warning. - InMacroArgs = true; - Args = ReadFunctionLikeMacroArgs(Identifier, MI); - - // Finished parsing args. - InMacroArgs = false; - - // If there was an error parsing the arguments, bail out. - if (Args == 0) return false; - - ++NumFnMacroExpanded; - } else { - ++NumMacroExpanded; - } - - // Notice that this macro has been used. - MI->setIsUsed(true); - - // If we started lexing a macro, enter the macro expansion body. - - // If this macro expands to no tokens, don't bother to push it onto the - // expansion stack, only to take it right back off. - if (MI->getNumTokens() == 0) { - // No need for arg info. - if (Args) Args->destroy(); - - // Ignore this macro use, just return the next token in the current - // buffer. - bool HadLeadingSpace = Identifier.hasLeadingSpace(); - bool IsAtStartOfLine = Identifier.isAtStartOfLine(); - - Lex(Identifier); - - // If the identifier isn't on some OTHER line, inherit the leading - // whitespace/first-on-a-line property of this token. This handles - // stuff like "! XX," -> "! ," and " XX," -> " ,", when XX is - // empty. - if (!Identifier.isAtStartOfLine()) { - if (IsAtStartOfLine) Identifier.setFlag(Token::StartOfLine); - if (HadLeadingSpace) Identifier.setFlag(Token::LeadingSpace); - } - ++NumFastMacroExpanded; - return false; - - } else if (MI->getNumTokens() == 1 && - isTrivialSingleTokenExpansion(MI, Identifier.getIdentifierInfo(), - *this)){ - // Otherwise, if this macro expands into a single trivially-expanded - // token: expand it now. This handles common cases like - // "#define VAL 42". - - // No need for arg info. - if (Args) Args->destroy(); - - // Propagate the isAtStartOfLine/hasLeadingSpace markers of the macro - // identifier to the expanded token. - bool isAtStartOfLine = Identifier.isAtStartOfLine(); - bool hasLeadingSpace = Identifier.hasLeadingSpace(); - - // Remember where the token is instantiated. - SourceLocation InstantiateLoc = Identifier.getLocation(); - - // Replace the result token. - Identifier = MI->getReplacementToken(0); - - // Restore the StartOfLine/LeadingSpace markers. - Identifier.setFlagValue(Token::StartOfLine , isAtStartOfLine); - Identifier.setFlagValue(Token::LeadingSpace, hasLeadingSpace); - - // Update the tokens location to include both its logical and physical - // locations. - SourceLocation Loc = - SourceMgr.getInstantiationLoc(Identifier.getLocation(), InstantiateLoc); - Identifier.setLocation(Loc); - - // If this is #define X X, we must mark the result as unexpandible. - if (IdentifierInfo *NewII = Identifier.getIdentifierInfo()) - if (getMacroInfo(NewII) == MI) - Identifier.setFlag(Token::DisableExpand); - - // Since this is not an identifier token, it can't be macro expanded, so - // we're done. - ++NumFastMacroExpanded; - return false; - } - - // Start expanding the macro. - EnterMacro(Identifier, Args); - - // Now that the macro is at the top of the include stack, ask the - // preprocessor to read the next token from it. - Lex(Identifier); - return false; -} - -/// ReadFunctionLikeMacroArgs - After reading "MACRO(", this method is -/// invoked to read all of the actual arguments specified for the macro -/// invocation. This returns null on error. -MacroArgs *Preprocessor::ReadFunctionLikeMacroArgs(Token &MacroName, - MacroInfo *MI) { - // The number of fixed arguments to parse. - unsigned NumFixedArgsLeft = MI->getNumArgs(); - bool isVariadic = MI->isVariadic(); - - // Outer loop, while there are more arguments, keep reading them. - Token Tok; - Tok.setKind(tok::comma); - --NumFixedArgsLeft; // Start reading the first arg. - - // ArgTokens - Build up a list of tokens that make up each argument. Each - // argument is separated by an EOF token. Use a SmallVector so we can avoid - // heap allocations in the common case. - llvm::SmallVector<Token, 64> ArgTokens; - - unsigned NumActuals = 0; - while (Tok.is(tok::comma)) { - // C99 6.10.3p11: Keep track of the number of l_parens we have seen. Note - // that we already consumed the first one. - unsigned NumParens = 0; - - while (1) { - // Read arguments as unexpanded tokens. This avoids issues, e.g., where - // an argument value in a macro could expand to ',' or '(' or ')'. - LexUnexpandedToken(Tok); - - if (Tok.is(tok::eof) || Tok.is(tok::eom)) { // "#if f(<eof>" & "#if f(\n" - Diag(MacroName, diag::err_unterm_macro_invoc); - // Do not lose the EOF/EOM. Return it to the client. - MacroName = Tok; - return 0; - } else if (Tok.is(tok::r_paren)) { - // If we found the ) token, the macro arg list is done. - if (NumParens-- == 0) - break; - } else if (Tok.is(tok::l_paren)) { - ++NumParens; - } else if (Tok.is(tok::comma) && NumParens == 0) { - // Comma ends this argument if there are more fixed arguments expected. - if (NumFixedArgsLeft) - break; - - // If this is not a variadic macro, too many args were specified. - if (!isVariadic) { - // Emit the diagnostic at the macro name in case there is a missing ). - // Emitting it at the , could be far away from the macro name. - Diag(MacroName, diag::err_too_many_args_in_macro_invoc); - return 0; - } - // Otherwise, continue to add the tokens to this variable argument. - } else if (Tok.is(tok::comment) && !KeepMacroComments) { - // If this is a comment token in the argument list and we're just in - // -C mode (not -CC mode), discard the comment. - continue; - } else if (Tok.is(tok::identifier)) { - // Reading macro arguments can cause macros that we are currently - // expanding from to be popped off the expansion stack. Doing so causes - // them to be reenabled for expansion. Here we record whether any - // identifiers we lex as macro arguments correspond to disabled macros. - // If so, we mark the token as noexpand. This is a subtle aspect of - // C99 6.10.3.4p2. - if (MacroInfo *MI = getMacroInfo(Tok.getIdentifierInfo())) - if (!MI->isEnabled()) - Tok.setFlag(Token::DisableExpand); - } - - ArgTokens.push_back(Tok); - } - - // Empty arguments are standard in C99 and supported as an extension in - // other modes. - if (ArgTokens.empty() && !Features.C99) - Diag(Tok, diag::ext_empty_fnmacro_arg); - - // Add a marker EOF token to the end of the token list for this argument. - Token EOFTok; - EOFTok.startToken(); - EOFTok.setKind(tok::eof); - EOFTok.setLocation(Tok.getLocation()); - EOFTok.setLength(0); - ArgTokens.push_back(EOFTok); - ++NumActuals; - --NumFixedArgsLeft; - }; - - // Okay, we either found the r_paren. Check to see if we parsed too few - // arguments. - unsigned MinArgsExpected = MI->getNumArgs(); - - // See MacroArgs instance var for description of this. - bool isVarargsElided = false; - - if (NumActuals < MinArgsExpected) { - // There are several cases where too few arguments is ok, handle them now. - if (NumActuals+1 == MinArgsExpected && MI->isVariadic()) { - // Varargs where the named vararg parameter is missing: ok as extension. - // #define A(x, ...) - // A("blah") - Diag(Tok, diag::ext_missing_varargs_arg); - - // Remember this occurred if this is a macro invocation with at least - // one actual argument. This allows us to elide the comma when used for - // cases like: - // #define A(x, foo...) blah(a, ## foo) - // #define A(x, ...) blah(a, ## __VA_ARGS__) - isVarargsElided = MI->getNumArgs() > 1; - } else if (MI->getNumArgs() == 1) { - // #define A(x) - // A() - // is ok because it is an empty argument. - - // Empty arguments are standard in C99 and supported as an extension in - // other modes. - if (ArgTokens.empty() && !Features.C99) - Diag(Tok, diag::ext_empty_fnmacro_arg); - } else { - // Otherwise, emit the error. - Diag(Tok, diag::err_too_few_args_in_macro_invoc); - return 0; - } - - // Add a marker EOF token to the end of the token list for this argument. - SourceLocation EndLoc = Tok.getLocation(); - Tok.startToken(); - Tok.setKind(tok::eof); - Tok.setLocation(EndLoc); - Tok.setLength(0); - ArgTokens.push_back(Tok); - } - - return MacroArgs::create(MI, &ArgTokens[0], ArgTokens.size(),isVarargsElided); -} - -/// ComputeDATE_TIME - Compute the current time, enter it into the specified -/// scratch buffer, then return DATELoc/TIMELoc locations with the position of -/// the identifier tokens inserted. -static void ComputeDATE_TIME(SourceLocation &DATELoc, SourceLocation &TIMELoc, - Preprocessor &PP) { - time_t TT = time(0); - struct tm *TM = localtime(&TT); - - static const char * const Months[] = { - "Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec" - }; - - char TmpBuffer[100]; - sprintf(TmpBuffer, "\"%s %2d %4d\"", Months[TM->tm_mon], TM->tm_mday, - TM->tm_year+1900); - DATELoc = PP.CreateString(TmpBuffer, strlen(TmpBuffer)); - - sprintf(TmpBuffer, "\"%02d:%02d:%02d\"", TM->tm_hour, TM->tm_min, TM->tm_sec); - TIMELoc = PP.CreateString(TmpBuffer, strlen(TmpBuffer)); -} - -/// ExpandBuiltinMacro - If an identifier token is read that is to be expanded -/// as a builtin macro, handle it and return the next token as 'Tok'. -void Preprocessor::ExpandBuiltinMacro(Token &Tok) { - // Figure out which token this is. - IdentifierInfo *II = Tok.getIdentifierInfo(); - assert(II && "Can't be a macro without id info!"); - - // If this is an _Pragma directive, expand it, invoke the pragma handler, then - // lex the token after it. - if (II == Ident_Pragma) - return Handle_Pragma(Tok); - - ++NumBuiltinMacroExpanded; - - char TmpBuffer[100]; - - // Set up the return result. - Tok.setIdentifierInfo(0); - Tok.clearFlag(Token::NeedsCleaning); - - if (II == Ident__LINE__) { - // __LINE__ expands to a simple numeric value. - sprintf(TmpBuffer, "%u", SourceMgr.getLogicalLineNumber(Tok.getLocation())); - unsigned Length = strlen(TmpBuffer); - Tok.setKind(tok::numeric_constant); - Tok.setLength(Length); - Tok.setLocation(CreateString(TmpBuffer, Length, Tok.getLocation())); - } else if (II == Ident__FILE__ || II == Ident__BASE_FILE__) { - SourceLocation Loc = Tok.getLocation(); - if (II == Ident__BASE_FILE__) { - Diag(Tok, diag::ext_pp_base_file); - SourceLocation NextLoc = SourceMgr.getIncludeLoc(Loc); - while (NextLoc.isValid()) { - Loc = NextLoc; - NextLoc = SourceMgr.getIncludeLoc(Loc); - } - } - - // Escape this filename. Turn '\' -> '\\' '"' -> '\"' - std::string FN = SourceMgr.getSourceName(SourceMgr.getLogicalLoc(Loc)); - FN = '"' + Lexer::Stringify(FN) + '"'; - Tok.setKind(tok::string_literal); - Tok.setLength(FN.size()); - Tok.setLocation(CreateString(&FN[0], FN.size(), Tok.getLocation())); - } else if (II == Ident__DATE__) { - if (!DATELoc.isValid()) - ComputeDATE_TIME(DATELoc, TIMELoc, *this); - Tok.setKind(tok::string_literal); - Tok.setLength(strlen("\"Mmm dd yyyy\"")); - Tok.setLocation(SourceMgr.getInstantiationLoc(DATELoc, Tok.getLocation())); - } else if (II == Ident__TIME__) { - if (!TIMELoc.isValid()) - ComputeDATE_TIME(DATELoc, TIMELoc, *this); - Tok.setKind(tok::string_literal); - Tok.setLength(strlen("\"hh:mm:ss\"")); - Tok.setLocation(SourceMgr.getInstantiationLoc(TIMELoc, Tok.getLocation())); - } else if (II == Ident__INCLUDE_LEVEL__) { - Diag(Tok, diag::ext_pp_include_level); - - // Compute the include depth of this token. - unsigned Depth = 0; - SourceLocation Loc = SourceMgr.getIncludeLoc(Tok.getLocation()); - for (; Loc.isValid(); ++Depth) - Loc = SourceMgr.getIncludeLoc(Loc); - - // __INCLUDE_LEVEL__ expands to a simple numeric value. - sprintf(TmpBuffer, "%u", Depth); - unsigned Length = strlen(TmpBuffer); - Tok.setKind(tok::numeric_constant); - Tok.setLength(Length); - Tok.setLocation(CreateString(TmpBuffer, Length, Tok.getLocation())); - } else if (II == Ident__TIMESTAMP__) { - // MSVC, ICC, GCC, VisualAge C++ extension. The generated string should be - // of the form "Ddd Mmm dd hh::mm::ss yyyy", which is returned by asctime. - Diag(Tok, diag::ext_pp_timestamp); - - // Get the file that we are lexing out of. If we're currently lexing from - // a macro, dig into the include stack. - const FileEntry *CurFile = 0; - Lexer *TheLexer = getCurrentFileLexer(); - - if (TheLexer) - CurFile = SourceMgr.getFileEntryForLoc(TheLexer->getFileLoc()); - - // If this file is older than the file it depends on, emit a diagnostic. - const char *Result; - if (CurFile) { - time_t TT = CurFile->getModificationTime(); - struct tm *TM = localtime(&TT); - Result = asctime(TM); - } else { - Result = "??? ??? ?? ??:??:?? ????\n"; - } - TmpBuffer[0] = '"'; - strcpy(TmpBuffer+1, Result); - unsigned Len = strlen(TmpBuffer); - TmpBuffer[Len-1] = '"'; // Replace the newline with a quote. - Tok.setKind(tok::string_literal); - Tok.setLength(Len); - Tok.setLocation(CreateString(TmpBuffer, Len, Tok.getLocation())); - } else { - assert(0 && "Unknown identifier!"); - } -} |