/* cond.c - conditional assembly pseudo-ops, and .include
- Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+ Copyright (C) 1990, 1991, 1992, 1993 Free Software Foundation, Inc.
-This file is part of GAS, the GNU Assembler.
+ 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 1, or (at your option)
-any later version.
+ 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.
+ 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. */
-
-/* static const char rcsid[] = "$Id$"; */
+ 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include "as.h"
#include "obstack.h"
-void s_ifdef(arg)
-int arg;
+/* This is allocated to grow and shrink as .ifdef/.endif pairs are scanned. */
+struct obstack cond_obstack;
+
+struct file_line
{
-/* register char c; */
- register char *name; /* points to name of symbol */
- register struct symbol * symbolP; /* Points to symbol */
-
- 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);
-
- /* ??? Should we try to optimize such that if we hit a .endif
- before a .else, we don't need to push state? */
- obstack_1grow(&cond_obstack, (symbolP != 0) ^ arg);
- }
-} /* s_ifdef() */
+ char *file;
+ unsigned int line;
+}; /* file_line */
-/* This is allocated to grow and shrink as .ifdef/.endif pairs
- are scanned. When the top element is nonzero, it means
- we should accept input. Otherwise, we should ignore input. */
-struct obstack cond_obstack;
+/* 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 */
-void s_if(arg)
-int arg;
+static void initialize_cframe PARAMS ((struct conditional_frame *cframe));
+static char *get_mri_string PARAMS ((int, int *));
+
+static struct conditional_frame *current_cframe = NULL;
+
+void
+s_ifdef (arg)
+ int arg;
{
- expressionS operand;
-
- 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");
-
- /* If the above error is signaled, this will dispatch
- using an undefined result. No big deal. */
- obstack_1grow(&cond_obstack, (operand.X_add_number != 0) ^ arg);
-} /* s_if() */
-
-void s_endif(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);
+ ignore_rest_of_line ();
+ }
+ else
+ {
+ char c;
+
+ c = get_symbol_end ();
+ symbolP = symbol_find (name);
+ *input_line_pointer = c;
+
+ initialize_cframe (&cframe);
+ cframe.ignoring = cframe.dead_tree || !((symbolP != 0) ^ arg);
+ current_cframe = ((struct conditional_frame *)
+ obstack_copy (&cond_obstack, &cframe,
+ sizeof (cframe)));
+ demand_empty_rest_of_line ();
+ } /* if a valid identifyer name */
+} /* s_ifdef() */
+
+void
+s_if (arg)
+ int arg;
{
- char *base = obstack_base(&cond_obstack);
- char *ptr = obstack_next_free(&cond_obstack);
-
- if (ptr-1 == base) {
- as_bad("unbalanced .endif");
- } else {
- obstack_free(&cond_obstack, ptr-1);
- cond_obstack.object_base = base;
- }
-} /* s_endif() */
+ expressionS operand;
+ struct conditional_frame cframe;
+ int t;
-void s_else(arg)
-int arg;
+ SKIP_WHITESPACE (); /* Leading whitespace is part of operand. */
+
+ if (current_cframe != NULL && current_cframe->ignoring)
+ {
+ operand.X_add_number = 0;
+ while (! is_end_of_line[(unsigned char) *input_line_pointer])
+ ++input_line_pointer;
+ }
+ else
+ {
+ expression (&operand);
+ if (operand.X_op != O_constant)
+ as_bad ("non-constant expression in \".if\" statement");
+ }
+
+ switch ((operatorT) arg)
+ {
+ case O_eq: t = operand.X_add_number == 0; break;
+ case O_ne: t = operand.X_add_number != 0; break;
+ case O_lt: t = operand.X_add_number < 0; break;
+ case O_le: t = operand.X_add_number <= 0; break;
+ case O_ge: t = operand.X_add_number >= 0; break;
+ case O_gt: t = operand.X_add_number > 0; break;
+ default:
+ abort ();
+ }
+
+ /* If the above error is signaled, this will dispatch
+ using an undefined result. No big deal. */
+ initialize_cframe (&cframe);
+ cframe.ignoring = cframe.dead_tree || ! t;
+ current_cframe = ((struct conditional_frame *)
+ obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));
+
+ demand_empty_rest_of_line ();
+} /* s_if() */
+
+/* Get a string for the MRI IFC or IFNC pseudo-ops. */
+
+static char *
+get_mri_string (terminator, len)
+ int terminator;
+ int *len;
{
- char *ptr = obstack_next_free(&cond_obstack);
- if (ptr-1 == obstack_base(&cond_obstack)) {
- as_bad(".else without matching .if");
- } else {
- ptr[-1] = !ptr[-1];
+ char *ret;
+ char *s;
+
+ SKIP_WHITESPACE ();
+ s = ret = input_line_pointer;
+ if (*input_line_pointer == '\'')
+ {
+ ++s;
+ ++input_line_pointer;
+ while (! is_end_of_line[(unsigned char) *input_line_pointer])
+ {
+ *s++ = *input_line_pointer++;
+ if (s[-1] == '\'')
+ {
+ if (*input_line_pointer != '\'')
+ break;
+ ++input_line_pointer;
+ }
}
-} /* s_else() */
+ SKIP_WHITESPACE ();
+ }
+ else
+ {
+ while (*input_line_pointer != terminator
+ && ! is_end_of_line[(unsigned char) *input_line_pointer])
+ ++input_line_pointer;
+ s = input_line_pointer;
+ while (s > ret && (s[-1] == ' ' || s[-1] == '\t'))
+ --s;
+ }
+
+ *len = s - ret;
+ return ret;
+}
+
+/* The MRI IFC and IFNC pseudo-ops. */
-void s_ifeqs(arg)
-int arg;
+void
+s_ifc (arg)
+ int arg;
{
- as_bad("ifeqs not implemented.");
-} /* s_ifeqs() */
+ char *s1, *s2;
+ int len1, len2;
+ int res;
+ struct conditional_frame cframe;
-void s_end(arg)
-int arg;
+ s1 = get_mri_string (',', &len1);
+
+ if (*input_line_pointer != ',')
+ as_bad ("bad format for ifc or ifnc");
+ else
+ ++input_line_pointer;
+
+ s2 = get_mri_string (';', &len2);
+
+ res = len1 == len2 && strncmp (s1, s2, len1) == 0;
+
+ initialize_cframe (&cframe);
+ cframe.ignoring = cframe.dead_tree || ! (res ^ arg);
+ current_cframe = ((struct conditional_frame *)
+ obstack_copy (&cond_obstack, &cframe, sizeof (cframe)));
+}
+
+void
+s_endif (arg)
+ int arg;
{
- ;
-} /* s_end() */
+ struct conditional_frame *hold;
-int ignore_input() {
- char *ptr = obstack_next_free (&cond_obstack);
+ 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 */
- /* We cannot ignore certain pseudo ops. */
- if (input_line_pointer[-1] == '.')
+ 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)
{
- if (input_line_pointer[0] == 'i'
- && (!strncmp (input_line_pointer, "if", 2)
- || !strncmp (input_line_pointer, "ifdef", 5)
- || !strncmp (input_line_pointer, "ifndef", 6)))
- return 0;
- if (input_line_pointer[0] == 'e'
- && (!strncmp (input_line_pointer, "else", 4)
- || !strncmp (input_line_pointer, "endif", 5)))
- return 0;
+ as_bad ("duplicate \"else\" - ignored");
+ as_bad_where (current_cframe->else_file_line.file,
+ current_cframe->else_file_line.line,
+ "here is the previous \"else\"");
+ as_bad_where (current_cframe->if_file_line.file,
+ current_cframe->if_file_line.line,
+ "here is the previous \"if\"");
}
+ else
+ {
+ as_where (¤t_cframe->else_file_line.file,
+ ¤t_cframe->else_file_line.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() */
+
+int
+ignore_input ()
+{
+ char *s;
+
+ s = input_line_pointer;
+
+ if (flag_mri
+#ifdef NO_PSEUDO_DOT
+ || 1
+#endif
+ )
+ {
+ if (s[-1] != '.')
+ --s;
+ }
+ else
+ {
+ if (s[-1] != '.')
+ return (current_cframe != NULL) && (current_cframe->ignoring);
+ }
+
+ /* We cannot ignore certain pseudo ops. */
+ if (((s[0] == 'i'
+ || s[0] == 'I')
+ && (!strncasecmp (s, "if", 2)
+ || !strncasecmp (s, "ifdef", 5)
+ || !strncasecmp (s, "ifndef", 6)))
+ || ((s[0] == 'e'
+ || s[0] == 'E')
+ && (!strncasecmp (s, "else", 4)
+ || !strncasecmp (s, "endif", 5)
+ || !strncasecmp (s, "endc", 4))))
+ 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));
+ as_where (&cframe->if_file_line.file,
+ &cframe->if_file_line.line);
+ cframe->previous_cframe = current_cframe;
+ cframe->dead_tree = current_cframe != NULL && current_cframe->ignoring;
+
+ return;
+} /* initialize_cframe() */
- return (ptr[-1] == 0);
-} /* ignore_input() */
+/*
+ * Local Variables:
+ * fill-column: 131
+ * comment-column: 0
+ * End:
+ */
/* end of cond.c */