Disambiguate Numbers and Identifiers

Use lookahead to determine whether a number is really a number or is
part of something forming an identifier.  This won't come into play
until the paste operator is recognized as a unique token.

llvm-svn: 142513
This commit is contained in:
David Greene 2011-10-19 13:03:39 +00:00
parent 9ba42085da
commit 5c9fa026dc
1 changed files with 37 additions and 1 deletions

View File

@ -132,8 +132,44 @@ tgtok::TokKind TGLexer::LexToken() {
return LexToken();
case '-': case '+':
case '0': case '1': case '2': case '3': case '4': case '5': case '6':
case '7': case '8': case '9':
case '7': case '8': case '9': {
int NextChar = 0;
if (isdigit(CurChar)) {
// Allow identifiers to start with a number if it is followed by
// an identifier. This can happen with paste operations like
// foo#8i.
int i = 0;
do {
NextChar = peekNextChar(i++);
} while (isdigit(NextChar));
if (NextChar == 'x' || NextChar == 'b') {
// If this is [0-9]b[01] or [0-9]x[0-9A-fa-f] this is most
// likely a number.
int NextNextChar = peekNextChar(i);
switch (NextNextChar) {
default:
break;
case '0': case '1':
if (NextChar == 'b')
return LexNumber();
// Fallthrough
case '2': case '3': case '4': case '5':
case '6': case '7': case '8': case '9':
case 'a': case 'b': case 'c': case 'd': case 'e': case 'f':
case 'A': case 'B': case 'C': case 'D': case 'E': case 'F':
if (NextChar == 'x')
return LexNumber();
break;
}
}
}
if (isalpha(NextChar) || NextChar == '_')
return LexIdentifier();
return LexNumber();
}
case '"': return LexString();
case '$': return LexVarName();
case '[': return LexBracket();