273 lines
11 KiB
C++
273 lines
11 KiB
C++
//===--- TokenConcatenation.cpp - Token Concatenation Avoidance -----------===//
|
|
//
|
|
// 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 TokenConcatenation class.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "clang/Lex/TokenConcatenation.h"
|
|
#include "clang/Basic/CharInfo.h"
|
|
#include "clang/Lex/Preprocessor.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
using namespace clang;
|
|
|
|
|
|
/// IsStringPrefix - Return true if Str is a string prefix.
|
|
/// 'L', 'u', 'U', or 'u8'. Including raw versions.
|
|
static bool IsStringPrefix(StringRef Str, bool CPlusPlus11) {
|
|
|
|
if (Str[0] == 'L' ||
|
|
(CPlusPlus11 && (Str[0] == 'u' || Str[0] == 'U' || Str[0] == 'R'))) {
|
|
|
|
if (Str.size() == 1)
|
|
return true; // "L", "u", "U", and "R"
|
|
|
|
// Check for raw flavors. Need to make sure the first character wasn't
|
|
// already R. Need CPlusPlus11 check for "LR".
|
|
if (Str[1] == 'R' && Str[0] != 'R' && Str.size() == 2 && CPlusPlus11)
|
|
return true; // "LR", "uR", "UR"
|
|
|
|
// Check for "u8" and "u8R"
|
|
if (Str[0] == 'u' && Str[1] == '8') {
|
|
if (Str.size() == 2) return true; // "u8"
|
|
if (Str.size() == 3 && Str[2] == 'R') return true; // "u8R"
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/// IsIdentifierStringPrefix - Return true if the spelling of the token
|
|
/// is literally 'L', 'u', 'U', or 'u8'. Including raw versions.
|
|
bool TokenConcatenation::IsIdentifierStringPrefix(const Token &Tok) const {
|
|
const LangOptions &LangOpts = PP.getLangOpts();
|
|
|
|
if (!Tok.needsCleaning()) {
|
|
if (Tok.getLength() < 1 || Tok.getLength() > 3)
|
|
return false;
|
|
SourceManager &SM = PP.getSourceManager();
|
|
const char *Ptr = SM.getCharacterData(SM.getSpellingLoc(Tok.getLocation()));
|
|
return IsStringPrefix(StringRef(Ptr, Tok.getLength()),
|
|
LangOpts.CPlusPlus11);
|
|
}
|
|
|
|
if (Tok.getLength() < 256) {
|
|
char Buffer[256];
|
|
const char *TokPtr = Buffer;
|
|
unsigned length = PP.getSpelling(Tok, TokPtr);
|
|
return IsStringPrefix(StringRef(TokPtr, length), LangOpts.CPlusPlus11);
|
|
}
|
|
|
|
return IsStringPrefix(StringRef(PP.getSpelling(Tok)), LangOpts.CPlusPlus11);
|
|
}
|
|
|
|
TokenConcatenation::TokenConcatenation(Preprocessor &pp) : PP(pp) {
|
|
memset(TokenInfo, 0, sizeof(TokenInfo));
|
|
|
|
// These tokens have custom code in AvoidConcat.
|
|
TokenInfo[tok::identifier ] |= aci_custom;
|
|
TokenInfo[tok::numeric_constant] |= aci_custom_firstchar;
|
|
TokenInfo[tok::period ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::amp ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::plus ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::minus ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::slash ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::less ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::greater ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::pipe ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::percent ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::colon ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::hash ] |= aci_custom_firstchar;
|
|
TokenInfo[tok::arrow ] |= aci_custom_firstchar;
|
|
|
|
// These tokens have custom code in C++11 mode.
|
|
if (PP.getLangOpts().CPlusPlus11) {
|
|
TokenInfo[tok::string_literal ] |= aci_custom;
|
|
TokenInfo[tok::wide_string_literal ] |= aci_custom;
|
|
TokenInfo[tok::utf8_string_literal ] |= aci_custom;
|
|
TokenInfo[tok::utf16_string_literal] |= aci_custom;
|
|
TokenInfo[tok::utf32_string_literal] |= aci_custom;
|
|
TokenInfo[tok::char_constant ] |= aci_custom;
|
|
TokenInfo[tok::wide_char_constant ] |= aci_custom;
|
|
TokenInfo[tok::utf16_char_constant ] |= aci_custom;
|
|
TokenInfo[tok::utf32_char_constant ] |= aci_custom;
|
|
}
|
|
|
|
// These tokens change behavior if followed by an '='.
|
|
TokenInfo[tok::amp ] |= aci_avoid_equal; // &=
|
|
TokenInfo[tok::plus ] |= aci_avoid_equal; // +=
|
|
TokenInfo[tok::minus ] |= aci_avoid_equal; // -=
|
|
TokenInfo[tok::slash ] |= aci_avoid_equal; // /=
|
|
TokenInfo[tok::less ] |= aci_avoid_equal; // <=
|
|
TokenInfo[tok::greater ] |= aci_avoid_equal; // >=
|
|
TokenInfo[tok::pipe ] |= aci_avoid_equal; // |=
|
|
TokenInfo[tok::percent ] |= aci_avoid_equal; // %=
|
|
TokenInfo[tok::star ] |= aci_avoid_equal; // *=
|
|
TokenInfo[tok::exclaim ] |= aci_avoid_equal; // !=
|
|
TokenInfo[tok::lessless ] |= aci_avoid_equal; // <<=
|
|
TokenInfo[tok::greatergreater] |= aci_avoid_equal; // >>=
|
|
TokenInfo[tok::caret ] |= aci_avoid_equal; // ^=
|
|
TokenInfo[tok::equal ] |= aci_avoid_equal; // ==
|
|
}
|
|
|
|
/// GetFirstChar - Get the first character of the token \arg Tok,
|
|
/// avoiding calls to getSpelling where possible.
|
|
static char GetFirstChar(Preprocessor &PP, const Token &Tok) {
|
|
if (IdentifierInfo *II = Tok.getIdentifierInfo()) {
|
|
// Avoid spelling identifiers, the most common form of token.
|
|
return II->getNameStart()[0];
|
|
} else if (!Tok.needsCleaning()) {
|
|
if (Tok.isLiteral() && Tok.getLiteralData()) {
|
|
return *Tok.getLiteralData();
|
|
} else {
|
|
SourceManager &SM = PP.getSourceManager();
|
|
return *SM.getCharacterData(SM.getSpellingLoc(Tok.getLocation()));
|
|
}
|
|
} else if (Tok.getLength() < 256) {
|
|
char Buffer[256];
|
|
const char *TokPtr = Buffer;
|
|
PP.getSpelling(Tok, TokPtr);
|
|
return TokPtr[0];
|
|
} else {
|
|
return PP.getSpelling(Tok)[0];
|
|
}
|
|
}
|
|
|
|
/// AvoidConcat - If printing PrevTok immediately followed by Tok would cause
|
|
/// the two individual tokens to be lexed as a single token, return true
|
|
/// (which causes a space to be printed between them). This allows the output
|
|
/// of -E mode to be lexed to the same token stream as lexing the input
|
|
/// directly would.
|
|
///
|
|
/// This code must conservatively return true if it doesn't want to be 100%
|
|
/// accurate. This will cause the output to include extra space characters,
|
|
/// but the resulting output won't have incorrect concatenations going on.
|
|
/// Examples include "..", which we print with a space between, because we
|
|
/// don't want to track enough to tell "x.." from "...".
|
|
bool TokenConcatenation::AvoidConcat(const Token &PrevPrevTok,
|
|
const Token &PrevTok,
|
|
const Token &Tok) const {
|
|
// First, check to see if the tokens were directly adjacent in the original
|
|
// source. If they were, it must be okay to stick them together: if there
|
|
// were an issue, the tokens would have been lexed differently.
|
|
SourceManager &SM = PP.getSourceManager();
|
|
SourceLocation PrevSpellLoc = SM.getSpellingLoc(PrevTok.getLocation());
|
|
SourceLocation SpellLoc = SM.getSpellingLoc(Tok.getLocation());
|
|
if (PrevSpellLoc.getLocWithOffset(PrevTok.getLength()) == SpellLoc)
|
|
return false;
|
|
|
|
tok::TokenKind PrevKind = PrevTok.getKind();
|
|
if (PrevTok.getIdentifierInfo()) // Language keyword or named operator.
|
|
PrevKind = tok::identifier;
|
|
|
|
// Look up information on when we should avoid concatenation with prevtok.
|
|
unsigned ConcatInfo = TokenInfo[PrevKind];
|
|
|
|
// If prevtok never causes a problem for anything after it, return quickly.
|
|
if (ConcatInfo == 0) return false;
|
|
|
|
if (ConcatInfo & aci_avoid_equal) {
|
|
// If the next token is '=' or '==', avoid concatenation.
|
|
if (Tok.is(tok::equal) || Tok.is(tok::equalequal))
|
|
return true;
|
|
ConcatInfo &= ~aci_avoid_equal;
|
|
}
|
|
|
|
if (ConcatInfo == 0) return false;
|
|
|
|
// Basic algorithm: we look at the first character of the second token, and
|
|
// determine whether it, if appended to the first token, would form (or
|
|
// would contribute) to a larger token if concatenated.
|
|
char FirstChar = 0;
|
|
if (ConcatInfo & aci_custom) {
|
|
// If the token does not need to know the first character, don't get it.
|
|
} else {
|
|
FirstChar = GetFirstChar(PP, Tok);
|
|
}
|
|
|
|
switch (PrevKind) {
|
|
default:
|
|
llvm_unreachable("InitAvoidConcatTokenInfo built wrong");
|
|
|
|
case tok::raw_identifier:
|
|
llvm_unreachable("tok::raw_identifier in non-raw lexing mode!");
|
|
|
|
case tok::string_literal:
|
|
case tok::wide_string_literal:
|
|
case tok::utf8_string_literal:
|
|
case tok::utf16_string_literal:
|
|
case tok::utf32_string_literal:
|
|
case tok::char_constant:
|
|
case tok::wide_char_constant:
|
|
case tok::utf16_char_constant:
|
|
case tok::utf32_char_constant:
|
|
if (!PP.getLangOpts().CPlusPlus11)
|
|
return false;
|
|
|
|
// In C++11, a string or character literal followed by an identifier is a
|
|
// single token.
|
|
if (Tok.getIdentifierInfo())
|
|
return true;
|
|
|
|
// A ud-suffix is an identifier. If the previous token ends with one, treat
|
|
// it as an identifier.
|
|
if (!PrevTok.hasUDSuffix())
|
|
return false;
|
|
// FALL THROUGH.
|
|
case tok::identifier: // id+id or id+number or id+L"foo".
|
|
// id+'.'... will not append.
|
|
if (Tok.is(tok::numeric_constant))
|
|
return GetFirstChar(PP, Tok) != '.';
|
|
|
|
if (Tok.getIdentifierInfo() || Tok.is(tok::wide_string_literal) ||
|
|
Tok.is(tok::utf8_string_literal) || Tok.is(tok::utf16_string_literal) ||
|
|
Tok.is(tok::utf32_string_literal) || Tok.is(tok::wide_char_constant) ||
|
|
Tok.is(tok::utf16_char_constant) || Tok.is(tok::utf32_char_constant))
|
|
return true;
|
|
|
|
// If this isn't identifier + string, we're done.
|
|
if (Tok.isNot(tok::char_constant) && Tok.isNot(tok::string_literal))
|
|
return false;
|
|
|
|
// Otherwise, this is a narrow character or string. If the *identifier*
|
|
// is a literal 'L', 'u8', 'u' or 'U', avoid pasting L "foo" -> L"foo".
|
|
return IsIdentifierStringPrefix(PrevTok);
|
|
|
|
case tok::numeric_constant:
|
|
return isPreprocessingNumberBody(FirstChar) ||
|
|
FirstChar == '+' || FirstChar == '-';
|
|
case tok::period: // ..., .*, .1234
|
|
return (FirstChar == '.' && PrevPrevTok.is(tok::period)) ||
|
|
isDigit(FirstChar) ||
|
|
(PP.getLangOpts().CPlusPlus && FirstChar == '*');
|
|
case tok::amp: // &&
|
|
return FirstChar == '&';
|
|
case tok::plus: // ++
|
|
return FirstChar == '+';
|
|
case tok::minus: // --, ->, ->*
|
|
return FirstChar == '-' || FirstChar == '>';
|
|
case tok::slash: //, /*, //
|
|
return FirstChar == '*' || FirstChar == '/';
|
|
case tok::less: // <<, <<=, <:, <%
|
|
return FirstChar == '<' || FirstChar == ':' || FirstChar == '%';
|
|
case tok::greater: // >>, >>=
|
|
return FirstChar == '>';
|
|
case tok::pipe: // ||
|
|
return FirstChar == '|';
|
|
case tok::percent: // %>, %:
|
|
return FirstChar == '>' || FirstChar == ':';
|
|
case tok::colon: // ::, :>
|
|
return FirstChar == '>' ||
|
|
(PP.getLangOpts().CPlusPlus && FirstChar == ':');
|
|
case tok::hash: // ##, #@, %:%:
|
|
return FirstChar == '#' || FirstChar == '@' || FirstChar == '%';
|
|
case tok::arrow: // ->*
|
|
return PP.getLangOpts().CPlusPlus && FirstChar == '*';
|
|
}
|
|
}
|