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/* Source code for RCC-Legacy.
Copyright (C) 2026 Richard Qin
This file is part of RCC.
RCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
RCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with RCC; see the file LICENSE. If not see
<http://www.gnu.org/licenses/>. */
%{
/* lexer.l - SysY2022 Lexer */
#include "rcc/ast.h"
#include "parser.tab.h"
#include <cstdlib>
#include <cstring>
// Line number tracking
int yylineno_val = 1;
#define YY_USER_ACTION yylloc.first_line = yylineno_val;
using namespace rcc;
%}
%option noyywrap nounput noinput
/* Exclusive start condition: multi-line comments */
%x COMMENT
%%
/* ─── Whitespace and Newlines ─── */
[ \t\r]+ { /* skip whitespace */ }
\n { yylineno_val++; }
/* ─── Comments ─── */
"//"[^\n]* { /* single-line comment */ }
"/*" { BEGIN(COMMENT); }
<COMMENT>"*/" { BEGIN(INITIAL); }
<COMMENT>\n { yylineno_val++; }
<COMMENT>. { /* eat anything inside comment */ }
/* ─── Keywords ─── */
"int" { return T_INT; }
"float" { return T_FLOAT; }
"void" { return T_VOID; }
"const" { return T_CONST; }
"if" { return T_IF; }
"else" { return T_ELSE; }
"while" { return T_WHILE; }
"break" { return T_BREAK; }
"continue" { return T_CONTINUE; }
"return" { return T_RETURN; }
/* ─── Integer Constants (Hex > Octal > Decimal, order is important) ─── */
0[xX][0-9a-fA-F]+ { yylval.int_val = static_cast<int32_t>(strtoul(yytext, nullptr, 16)); return INT_CONST; }
0[0-7]+ { yylval.int_val = static_cast<int32_t>(strtoul(yytext, nullptr, 8)); return INT_CONST; }
[0-9]+ { yylval.int_val = static_cast<int32_t>(strtoul(yytext, nullptr, 10)); return INT_CONST; }
/* ─── Floating Point Constants (Hex float + Decimal float) ─── */
0[xX][0-9a-fA-F]*\.[0-9a-fA-F]+([pP][+-]?[0-9]+)? { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
0[xX][0-9a-fA-F]+\.[0-9a-fA-F]*([pP][+-]?[0-9]+)? { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
0[xX][0-9a-fA-F]+[pP][+-]?[0-9]+ { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
[0-9]*\.[0-9]+([eE][+-]?[0-9]+)? { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
[0-9]+\.[0-9]*([eE][+-]?[0-9]+)? { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
[0-9]+[eE][+-]?[0-9]+ { yylval.float_val = strtof(yytext, nullptr); return FLOAT_CONST; }
/* ─── Identifiers ─── */
[a-zA-Z_][a-zA-Z0-9_]* { yylval.str_val = strdup(yytext); return IDENT; }
/* ─── Multi-character Operators ─── */
"&&" { return T_AND; }
"||" { return T_OR; }
"<=" { return T_LE; }
">=" { return T_GE; }
"==" { return T_EQ; }
"!=" { return T_NE; }
/* ─── Format Strings (for putf only) ─── */
\"[^\"]*\" { yylval.str_val = strdup(yytext); return STRING_CONST; }
/* ─── Single-character Operators and Delimiters, return ASCII directly ─── */
. { return yytext[0]; }
%%
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