usr/src/usr.bin/gas/as.h

/* as.h - global header file
   Copyright (C) 1987 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 1, 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 asH
#define asH                     /* Don't declare things twice. */

#if !defined(__STDC__) && !defined(const)
#define const /* ignore */
#endif

#ifdef USG
#define index strchr
#define bzero(s,n) memset((s),0,(n))
#define bcopy(from,to,n) memcpy((to),(from),(n))
#define setbuffer(a,b,c)
#endif

/*
 * CAPITALISED names are #defined.
 * "lowercaseH" is #defined if "lowercase.h" has been #include-d.
 * "lowercaseT" is a typedef of "lowercase" objects.
 * "lowercaseP" is type "pointer to object of type 'lowercase'".
 * "lowercaseS" is typedef struct ... lowercaseS.
 *
 * #define SUSPECT when debugging.
 * #define DUMP to include data-structure dumpers.
 * #define COMMON as "extern" for all modules except one, where you #define
 *      COMMON as "".
 * If TEST is #defined, then we are testing a module: #define COMMON as "".
 */


/* These #defines are for parameters of entire assembler. */

/* #define SUSPECT JF remove for speed testing */
/* #define DUMP */
#define NDEBUG          /* JF disable asserts */
/* These #includes are for type definitions etc. */

/* #include "style.h" */
#include <stdio.h>
#include <assert.h>
#define obstack_chunk_alloc     xmalloc
#define obstack_chunk_free      xfree

/* These defines are potentially useful */
#define FALSE   (0)
#define TRUE    (!FALSE)
#define ASSERT  assert
#define BAD_CASE(value)                                                 \
{                                                                       \
  as_fatal ("Case value %d unexpected at line %d of file \"%s\"\n",     \
           value, __LINE__, __FILE__);                                  \
}


\f
/* These are assembler-wide concepts */


#ifndef COMMON
#ifdef TEST
#define COMMON                  /* declare our COMMONs storage here. */
#else
#define COMMON extern           /* our commons live elswhere */
#endif
#endif
                                /* COMMON now defined */

#ifdef SUSPECT
#define register                /* no registers: helps debugging */
#define know(p) ASSERT(p)       /* know() is less ugly than #ifdef SUSPECT/ */
                                /* assert()/#endif. */
#else
#define know(p)                 /* know() checks are no-op.ed */
#endif                          /* #ifdef SUSPECT */


char    *xmalloc();             /* keep C compilers happy */
char    *xrealloc();            /* " */
void    free();                 /* " */
#define xfree free
\f
/* input_scrub.c */

/*
 * Supplies sanitised buffers to read.c.
 * Also understands printing line-number part of error messages.
 */

                                /* Line number things. */
int     seen_at_least_1_file();
void    bump_line_counters();
void    new_logical_line();
void    as_where();
void    as_perror();
void    as_howmuch();
                                /* Sanitising things. */
void    input_scrub_begin();
void    input_scrub_end();
char    *input_scrub_new_file();
char    *input_scrub_next_buffer();
\f
/* subsegs.c     Sub-segments. Also, segment(=expression type)s.*/

/*
 * This table describes the use of segments as EXPRESSION types.
 *
 *      X_seg   X_add_symbol  X_subtract_symbol X_add_number
 * SEG_NONE                                             no (legal) expression
 * SEG_PASS1                                            no (defined) "
 * SEG_BIG                                      *       > 32 bits const.
 * SEG_ABSOLUTE                                 0
 * SEG_DATA             *                       0
 * SEG_TEXT             *                       0
 * SEG_BSS              *                       0
 * SEG_UNKNOWN          *                       0
 * SEG_DIFFERENCE       0               *       0
 *
 * The blank fields MUST be 0, and are nugatory.
 * The '0' fields MAY be 0. The '*' fields MAY NOT be 0.
 *
 * SEG_BIG: X_add_number is < 0 if the result is in
 *      generic_floating_point_number.  The value is -'c' where c is the
 *      character that introduced the constant.  e.g. "0f6.9" will have  -'f'
 *      as a X_add_number value.
 *      X_add_number > 0 is a count of how many littlenums it took to
 *      represent a bignum.
 * SEG_DIFFERENCE:
 * If segments of both symbols are known, they are the same segment.
 * X_add_symbol != X_sub_symbol (then we just cancel them, => SEG_ABSOLUTE).
 */

typedef enum
{
        SEG_ABSOLUTE,
        SEG_TEXT,
        SEG_DATA,
        SEG_BSS,
        SEG_UNKNOWN,
        SEG_NONE,               /* Mythical Segment: NO expression seen. */
        SEG_PASS1,              /* Mythical Segment: Need another pass. */
        SEG_GOOF,               /* Only happens if AS has a logic error. */
                                /* Invented so we don't crash printing */
                                /* error message involving weird segment. */
        SEG_BIG,                        /* Bigger than 32 bits constant. */
        SEG_DIFFERENCE          /* Mythical Segment: absolute difference. */
}               segT;
#define SEG_MAXIMUM_ORDINAL (SEG_DIFFERENCE)

typedef unsigned char   subsegT;

COMMON subsegT                  now_subseg;
                                /* What subseg we are accreting now? */


COMMON segT                     now_seg;
                                /* Segment our instructions emit to. */
                                /* Only OK values are SEG_TEXT or SEG_DATA. */


extern char *const seg_name[];
extern const int   seg_N_TYPE[];
extern const segT  N_TYPE_seg[];
void    subsegs_begin();
void    subseg_change();
void    subseg_new();
\f
/* relax() */

typedef enum
{
        rs_fill,                /* Variable chars to be repeated fr_offset */
                                /* times. Fr_symbol unused. */
                                /* Used with fr_offset == 0 for a constant */
                                /* length frag. */

        rs_align,               /* Align: Fr_offset: power of 2. */
                                /* 1 variable char: fill character. */
        rs_org,                 /* Org: Fr_offset, fr_symbol: address. */
                                /* 1 variable char: fill character. */

        rs_machine_dependent,
#ifndef WORKING_DOT_WORD
        rs_broken_word,         /* JF: gunpoint */
#endif
}
relax_stateT;

/* typedef unsigned char relax_substateT; */
/* JF this is more likely to leave the end of a struct frag on an align
   boundry.  Be very careful with this.  */
typedef unsigned long int relax_substateT;

typedef unsigned long int relax_addressT;/* Enough bits for address. */
                                /* Still an integer type. */

\f
/* frags.c */

/*
 * A code fragment (frag) is some known number of chars, followed by some
 * unknown number of chars. Typically the unknown number of chars is an
 * instruction address whose size is yet unknown. We always know the greatest
 * possible size the unknown number of chars may become, and reserve that
 * much room at the end of the frag.
 * Once created, frags do not change address during assembly.
 * We chain the frags in (a) forward-linked list(s). The object-file address
 * of the 1st char of a frag is generally not known until after relax().
 * Many things at assembly time describe an address by {object-file-address
 * of a particular frag}+offset.

 BUG: it may be smarter to have a single pointer off to various different
notes for different frag kinds. See how code pans out.


 */
struct frag                     /* a code fragment */
{
        long unsigned int fr_address; /* Object file address. */
        struct frag *fr_next;   /* Chain forward; ascending address order. */
                                /* Rooted in frch_root. */

        long int fr_fix;        /* (Fixed) number of chars we know we have. */
                                /* May be 0. */
        long int fr_var;        /* (Variable) number of chars after above. */
                                /* May be 0. */
        struct symbol *fr_symbol; /* For variable-length tail. */
        long int fr_offset;     /* For variable-length tail. */
        char    *fr_opcode;     /*->opcode low addr byte,for relax()ation*/
        relax_stateT fr_type;   /* What state is my tail in? */
        relax_substateT fr_subtype;
                /* These are needed only on the NS32K machines */
        char    fr_pcrel_adjust;
        char    fr_bsr;
        char    fr_literal [1]; /* Chars begin here. */
                                /* One day we will compile fr_literal[0]. */
};
#define SIZEOF_STRUCT_FRAG \
 ((int)zero_address_frag.fr_literal-(int)&zero_address_frag)
                                /* We want to say fr_literal[0] above. */

typedef struct frag fragS;

COMMON fragS *  frag_now;       /* -> current frag we are building. */
                                /* This frag is incomplete. */
                                /* It is, however, included in frchain_now. */
                                /* Frag_now->fr_fix is bogus. Use: */
/* Virtual frag_now->fr_fix==obstack_next_free(&frags)-frag_now->fr_literal.*/

COMMON fragS zero_address_frag; /* For foreign-segment symbol fixups. */
COMMON fragS  bss_address_frag; /* For local common (N_BSS segment) fixups. */

void            frag_new();
char *          frag_more();
char *          frag_var();
void            frag_wane();
void            frag_align();
\f

/* main program "as.c" (command arguments etc) */

COMMON char
flagseen[128];                  /* ['x'] TRUE if "-x" seen. */

COMMON char *
out_file_name;                  /* name of emitted object file */

COMMON int      need_pass_2;    /* TRUE if we need a second pass. */


#endif                          /* #ifdef asH */

/* end: as.h */