240 lines
6.3 KiB
C
240 lines
6.3 KiB
C
/* cond.c - conditional assembly pseudo-ops, and .include
|
|
Copyright (C) 1990, 1991, 1992 Free Software Foundation, Inc.
|
|
|
|
This file is part of GAS, the GNU Assembler.
|
|
|
|
GAS 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, or (at your option)
|
|
any later version.
|
|
|
|
GAS 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 GAS; see the file COPYING. If not, write to
|
|
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
|
|
|
|
#ifndef lint
|
|
static char rcsid[] = "$Id: cond.c,v 1.1 1993/10/02 20:57:20 pk Exp $";
|
|
#endif
|
|
|
|
#include "as.h"
|
|
|
|
#include "obstack.h"
|
|
|
|
/* This is allocated to grow and shrink as .ifdef/.endif pairs are scanned. */
|
|
struct obstack cond_obstack;
|
|
|
|
struct file_line {
|
|
char *logical_file;
|
|
int logical_line;
|
|
char *physical_file;
|
|
int physical_line;
|
|
}; /* file_line */
|
|
|
|
/* This is what we push and pop. */
|
|
struct conditional_frame {
|
|
struct file_line if_file_line; /* the source file & line number of the "if" */
|
|
struct file_line else_file_line; /* the source file & line of the "else" */
|
|
struct conditional_frame *previous_cframe;
|
|
int else_seen; /* have we seen an else yet? */
|
|
int ignoring; /* if we are currently ignoring input. */
|
|
int dead_tree; /* if a conditional at a higher level is ignoring input. */
|
|
}; /* conditional_frame */
|
|
|
|
#if __STDC__ == 1
|
|
|
|
static void get_file_line(struct file_line *into);
|
|
static void initialize_cframe(struct conditional_frame *cframe);
|
|
static void set_file_line(struct file_line *from);
|
|
|
|
#else
|
|
|
|
static void get_file_line();
|
|
static void initialize_cframe();
|
|
static void set_file_line();
|
|
|
|
#endif
|
|
|
|
static struct conditional_frame *current_cframe = NULL;
|
|
|
|
void s_ifdef(arg)
|
|
int arg;
|
|
{
|
|
register char *name; /* points to name of symbol */
|
|
register struct symbol *symbolP; /* Points to symbol */
|
|
struct conditional_frame cframe;
|
|
|
|
SKIP_WHITESPACE(); /* Leading whitespace is part of operand. */
|
|
name = input_line_pointer;
|
|
|
|
if (!is_name_beginner(*name)) {
|
|
as_bad("invalid identifier for \".ifdef\"");
|
|
obstack_1grow(&cond_obstack, 0);
|
|
} else {
|
|
get_symbol_end();
|
|
++input_line_pointer;
|
|
symbolP = symbol_find(name);
|
|
|
|
initialize_cframe(&cframe);
|
|
cframe.ignoring = cframe.dead_tree && !((symbolP != 0) ^ arg);
|
|
current_cframe = (struct conditional_frame *) obstack_copy(&cond_obstack, &cframe, sizeof(cframe));
|
|
} /* if a valid identifyer name */
|
|
|
|
return;
|
|
} /* s_ifdef() */
|
|
|
|
void s_if(arg)
|
|
int arg;
|
|
{
|
|
expressionS operand;
|
|
struct conditional_frame cframe;
|
|
|
|
SKIP_WHITESPACE(); /* Leading whitespace is part of operand. */
|
|
expr(0, &operand);
|
|
|
|
if (operand.X_add_symbol != NULL
|
|
|| operand.X_subtract_symbol != NULL) {
|
|
as_bad("non-constant expression in \".if\" statement");
|
|
} /* bad condition */
|
|
|
|
/* If the above error is signaled, this will dispatch
|
|
using an undefined result. No big deal. */
|
|
initialize_cframe(&cframe);
|
|
cframe.ignoring = cframe.dead_tree || !((operand.X_add_number != 0) ^ arg);
|
|
current_cframe = (struct conditional_frame *) obstack_copy(&cond_obstack, &cframe, sizeof(cframe));
|
|
return;
|
|
} /* s_if() */
|
|
|
|
void s_endif(arg)
|
|
int arg;
|
|
{
|
|
struct conditional_frame *hold;
|
|
|
|
if (current_cframe == NULL) {
|
|
as_bad("\".endif\" without \".if\"");
|
|
} else {
|
|
hold = current_cframe;
|
|
current_cframe = current_cframe->previous_cframe;
|
|
obstack_free(&cond_obstack, hold);
|
|
} /* if one pop too many */
|
|
|
|
return;
|
|
} /* s_endif() */
|
|
|
|
void s_else(arg)
|
|
int arg;
|
|
{
|
|
if (current_cframe == NULL) {
|
|
as_bad(".else without matching .if - ignored");
|
|
|
|
} else if (current_cframe->else_seen) {
|
|
struct file_line hold;
|
|
as_bad("duplicate \"else\" - ignored");
|
|
|
|
get_file_line(&hold);
|
|
set_file_line(¤t_cframe->else_file_line);
|
|
as_bad("here is the previous \"else\".");
|
|
set_file_line(¤t_cframe->if_file_line);
|
|
as_bad("here is the matching \".if\".");
|
|
set_file_line(&hold);
|
|
|
|
} else {
|
|
get_file_line(¤t_cframe->else_file_line);
|
|
|
|
if (!current_cframe->dead_tree) {
|
|
current_cframe->ignoring = !current_cframe->ignoring;
|
|
} /* if not a dead tree */
|
|
|
|
current_cframe->else_seen = 1;
|
|
} /* if error else do it */
|
|
|
|
return;
|
|
} /* s_else() */
|
|
|
|
void s_ifeqs(arg)
|
|
int arg;
|
|
{
|
|
as_bad("ifeqs not implemented.");
|
|
|
|
return;
|
|
} /* s_ifeqs() */
|
|
|
|
void s_end(arg)
|
|
int arg;
|
|
{
|
|
return;
|
|
} /* s_end() */
|
|
|
|
int ignore_input() {
|
|
char *ptr = obstack_next_free (&cond_obstack);
|
|
|
|
/* We cannot ignore certain pseudo ops. */
|
|
if (input_line_pointer[-1] == '.'
|
|
&& ((input_line_pointer[0] == 'i'
|
|
&& (!strncmp (input_line_pointer, "if", 2)
|
|
|| !strncmp (input_line_pointer, "ifdef", 5)
|
|
|| !strncmp (input_line_pointer, "ifndef", 6)))
|
|
|| (input_line_pointer[0] == 'e'
|
|
&& (!strncmp (input_line_pointer, "else", 4)
|
|
|| !strncmp (input_line_pointer, "endif", 5))))) {
|
|
return 0;
|
|
}
|
|
|
|
return((current_cframe != NULL) && (current_cframe->ignoring));
|
|
} /* ignore_input() */
|
|
|
|
static void initialize_cframe(cframe)
|
|
struct conditional_frame *cframe;
|
|
{
|
|
memset(cframe, 0, sizeof(*cframe));
|
|
get_file_line(&(cframe->if_file_line));
|
|
cframe->previous_cframe = current_cframe;
|
|
cframe->dead_tree = current_cframe != NULL && current_cframe->ignoring;
|
|
|
|
return;
|
|
} /* initialize_cframe() */
|
|
|
|
static void get_file_line(into)
|
|
struct file_line *into;
|
|
{
|
|
extern char *logical_input_file;
|
|
extern char *physical_input_file;
|
|
extern int logical_input_line;
|
|
extern int physical_input_line;
|
|
|
|
into->logical_file = logical_input_file;
|
|
into->logical_line = logical_input_line;
|
|
into->physical_file = physical_input_file;
|
|
into->physical_line = physical_input_line;
|
|
|
|
return;
|
|
} /* get_file_line() */
|
|
|
|
static void set_file_line(from)
|
|
struct file_line *from;
|
|
{
|
|
extern char *logical_input_file;
|
|
extern char *physical_input_file;
|
|
extern int logical_input_line;
|
|
extern int physical_input_line;
|
|
|
|
logical_input_file = from->logical_file;
|
|
logical_input_line = from->logical_line;
|
|
physical_input_file = from->physical_file;
|
|
physical_input_line = from->physical_line;
|
|
return;
|
|
} /* set_file_line() */
|
|
|
|
/*
|
|
* Local Variables:
|
|
* fill-column: 131
|
|
* comment-column: 0
|
|
* End:
|
|
*/
|
|
|
|
/* end of cond.c */
|