%{
/* sbc.y: A POSIX bc processor written for minix with no extensions. */
/* This file is part of GNU bc.
Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc.
This program 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 2 of the License , or
(at your option) any later version.
This program 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 this program; see the file COPYING. If not, write to
The Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor
Boston, MA 02110-1301 USA
You may contact the author by:
e-mail: philnelson@acm.org
us-mail: Philip A. Nelson
Computer Science Department, 9062
Western Washington University
Bellingham, WA 98226-9062
*************************************************************************/
#include "bcdefs.h"
#include "global.h" /* To get the global variables. */
#include "proto.h"
%}
%start program
%union {
char *s_value;
char c_value;
int i_value;
arg_list *a_value;
}
%token <i_value> ENDOFLINE AND OR NOT
%token <s_value> STRING NAME NUMBER
/* '-', '+' are tokens themselves */
%token <c_value> ASSIGN_OP
/* '=', '+=', '-=', '*=', '/=', '%=', '^=' */
%token <s_value> REL_OP
/* '==', '<=', '>=', '!=', '<', '>' */
%token <c_value> INCR_DECR
/* '++', '--' */
%token <i_value> Define Break Quit Length
/* 'define', 'break', 'quit', 'length' */
%token <i_value> Return For If While Sqrt Else
/* 'return', 'for', 'if', 'while', 'sqrt', 'else' */
%token <i_value> Scale Ibase Obase Auto Read
/* 'scale', 'ibase', 'obase', 'auto', 'read' */
%token <i_value> Warranty, Halt, Last, Continue, Print, Limits
/* 'warranty', 'halt', 'last', 'continue', 'print', 'limits' */
/* The types of all other non-terminals. */
%type <i_value> expression named_expression return_expression
%type <a_value> opt_parameter_list parameter_list opt_auto_define_list
%type <a_value> define_list opt_argument_list argument_list
%type <i_value> program input_item semicolon_list statement_list
%type <i_value> statement_or_error statement function relational_expression
/* precedence */
%nonassoc REL_OP
%right ASSIGN_OP
%left '+' '-'
%left '*' '/' '%'
%right '^'
%nonassoc UNARY_MINUS
%nonassoc INCR_DECR
%%
program : /* empty */
{
$$ = 0;
std_only = TRUE;
if (interactive && !quiet)
{
show_bc_version ();
welcome ();
}
}
| program input_item
;
input_item : semicolon_list ENDOFLINE
{ run_code (); }
| function
{ run_code (); }
| error ENDOFLINE
{
yyerrok;
init_gen () ;
}
;
semicolon_list : /* empty */
{ $$ = 0; }
| statement_or_error
| semicolon_list ';' statement_or_error
| semicolon_list ';'
;
statement_list : /* empty */
{ $$ = 0; }
| statement
| statement_list ENDOFLINE
| statement_list ENDOFLINE statement
| statement_list ';'
| statement_list ';' statement
;
statement_or_error : statement
| error statement
{ $$ = $2; }
;
statement : Warranty
{ warranty ("s"); }
| expression
{
if ($1 & 1)
generate ("W");
else
generate ("p");
}
| STRING
{
$$ = 0;
generate ("w");
generate ($1);
free ($1);
}
| Break
{
if (break_label == 0)
yyerror ("Break outside a for/while");
else
{
sprintf (genstr, "J%1d:", break_label);
generate (genstr);
}
}
| Quit
{ bc_exit (0); }
| Return
{ generate ("0R"); }
| Return '(' return_expression ')'
{ generate ("R"); }
| For
{
$1 = break_label;
break_label = next_label++;
}
'(' expression ';'
{
$4 = next_label++;
sprintf (genstr, "pN%1d:", $4);
generate (genstr);
}
relational_expression ';'
{
$7 = next_label++;
sprintf (genstr, "B%1d:J%1d:", $7, break_label);
generate (genstr);
$<i_value>$ = next_label++;
sprintf (genstr, "N%1d:", $<i_value>$);
generate (genstr);
}
expression ')'
{
sprintf (genstr, "pJ%1d:N%1d:", $4, $7);
generate (genstr);
}
statement
{
sprintf (genstr, "J%1d:N%1d:", $<i_value>9,
break_label);
generate (genstr);
break_label = $1;
}
| If '(' relational_expression ')'
{
$3 = next_label++;
sprintf (genstr, "Z%1d:", $3);
generate (genstr);
}
statement
{
sprintf (genstr, "N%1d:", $3);
generate (genstr);
}
| While
{
$1 = next_label++;
sprintf (genstr, "N%1d:", $1);
generate (genstr);
}
'(' relational_expression
{
$4 = break_label;
break_label = next_label++;
sprintf (genstr, "Z%1d:", break_label);
generate (genstr);
}
')' statement
{
sprintf (genstr, "J%1d:N%1d:", $1, break_label);
generate (genstr);
break_label = $4;
}
| '{' statement_list '}'
{ $$ = 0; }
;
function : Define NAME '(' opt_parameter_list ')' '{'
ENDOFLINE opt_auto_define_list
{ char *params, *autos;
check_params ($4,$8);
params = arg_str ($4);
autos = arg_str ($8);
set_genstr_size (30 + strlen (params)
+ strlen (autos));
sprintf (genstr, "F%d,%s.%s[", lookup ($2,FUNCT),
params, autos);
generate (genstr);
free_args ($4);
free_args ($8);
$1 = next_label;
next_label = 0;
}
statement_list ENDOFLINE '}'
{
generate ("0R]");
next_label = $1;
}
;
opt_parameter_list : /* empty */
{ $$ = NULL; }
| parameter_list
;
parameter_list : NAME
{ $$ = nextarg (NULL, lookup ($1,SIMPLE), FALSE); }
| define_list ',' NAME
{ $$ = nextarg ($1, lookup ($3,SIMPLE), FALSE); }
;
opt_auto_define_list : /* empty */
{ $$ = NULL; }
| Auto define_list ENDOFLINE
{ $$ = $2; }
| Auto define_list ';'
{ $$ = $2; }
;
define_list : NAME
{ $$ = nextarg (NULL, lookup ($1,SIMPLE), FALSE); }
| NAME '[' ']'
{ $$ = nextarg (NULL, lookup ($1,ARRAY), FALSE); }
| define_list ',' NAME
{ $$ = nextarg ($1, lookup ($3,SIMPLE), FALSE); }
| define_list ',' NAME '[' ']'
{ $$ = nextarg ($1, lookup ($3,ARRAY), FALSE); }
;
opt_argument_list : /* empty */
{ $$ = NULL; }
| argument_list
;
argument_list : expression
{ $$ = nextarg (NULL,0, FALSE); }
| argument_list ',' expression
{ $$ = nextarg ($1,0, FALSE); }
;
relational_expression : expression
{ $$ = 0; }
| expression REL_OP expression
{
$$ = 0;
switch (*($2))
{
case '=':
generate ("=");
break;
case '!':
generate ("#");
break;
case '<':
if ($2[1] == '=')
generate ("{");
else
generate ("<");
break;
case '>':
if ($2[1] == '=')
generate ("}");
else
generate (">");
break;
}
}
;
return_expression : /* empty */
{
$$ = 0;
generate ("0");
}
| expression
;
expression : named_expression ASSIGN_OP
{
if ($2 != '=')
{
if ($1 < 0)
sprintf (genstr, "DL%d:", -$1);
else
sprintf (genstr, "l%d:", $1);
generate (genstr);
}
}
expression
{
$$ = 0;
if ($2 != '=')
{
sprintf (genstr, "%c", $2);
generate (genstr);
}
if ($1 < 0)
sprintf (genstr, "S%d:", -$1);
else
sprintf (genstr, "s%d:", $1);
generate (genstr);
}
| expression '+' expression
{ generate ("+"); }
| expression '-' expression
{ generate ("-"); }
| expression '*' expression
{ generate ("*"); }
| expression '/' expression
{ generate ("/"); }
| expression '%' expression
{ generate ("%"); }
| expression '^' expression
{ generate ("^"); }
| '-' expression %prec UNARY_MINUS
{ generate ("n"); $$ = 1;}
| named_expression
{
$$ = 1;
if ($1 < 0)
sprintf (genstr, "L%d:", -$1);
else
sprintf (genstr, "l%d:", $1);
generate (genstr);
}
| NUMBER
{
int len = strlen ($1);
$$ = 1;
if (len == 1 && *$1 == '0')
generate ("0");
else
{
if (len == 1 && *$1 == '1')
generate ("1");
else
{
generate ("K");
generate ($1);
generate (":");
}
free ($1);
}
}
| '(' expression ')'
{ $$ = 1; }
| NAME '(' opt_argument_list ')'
{
$$ = 1;
if ($3 != NULL)
{ char *params = call_str ($3);
set_genstr_size (20 + strlen (params));
sprintf (genstr, "C%d,%s:",
lookup ($1,FUNCT), params);
free_args ($3);
}
else
sprintf (genstr, "C%d:", lookup ($1,FUNCT));
generate (genstr);
}
| INCR_DECR named_expression
{
$$ = 1;
if ($2 < 0)
{
if ($1 == '+')
sprintf (genstr, "DA%d:L%d:", -$2, -$2);
else
sprintf (genstr, "DM%d:L%d:", -$2, -$2);
}
else
{
if ($1 == '+')
sprintf (genstr, "i%d:l%d:", $2, $2);
else
sprintf (genstr, "d%d:l%d:", $2, $2);
}
generate (genstr);
}
| named_expression INCR_DECR
{
$$ = 1;
if ($1 < 0)
{
sprintf (genstr, "DL%d:x", -$1);
generate (genstr);
if ($2 == '+')
sprintf (genstr, "A%d:", -$1);
else
sprintf (genstr, "M%d:", -$1);
}
else
{
sprintf (genstr, "l%d:", $1);
generate (genstr);
if ($2 == '+')
sprintf (genstr, "i%d:", $1);
else
sprintf (genstr, "d%d:", $1);
}
generate (genstr);
}
| Length '(' expression ')'
{ generate ("cL"); $$ = 1;}
| Sqrt '(' expression ')'
{ generate ("cR"); $$ = 1;}
| Scale '(' expression ')'
{ generate ("cS"); $$ = 1;}
;
named_expression : NAME
{ $$ = lookup ($1,SIMPLE); }
| NAME '[' expression ']'
{ $$ = lookup ($1,ARRAY); }
| Ibase
{ $$ = 0; }
| Obase
{ $$ = 1; }
| Scale
{ $$ = 2; }
;
%%