rs6000.h

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/* IBM RS/6000 "XCOFF" file definitions for BFD.
   Copyright (C) 1990, 1991 Free Software Foundation, Inc.
   FIXME: Can someone provide a transliteration of this name into ASCII?
   Using the following chars caused a compiler warning on HIUX (so I replaced
   them with octal escapes), and isn't useful without an understanding of what
   character set it is.
   Written by Mimi Ph\373\364ng-Th\345o V\365 of IBM
   and John Gilmore of Cygnus Support.  */

/********************** FILE HEADER **********************/

struct external_filehdr {
    char f_magic[2];    /* magic number         */
    char f_nscns[2];    /* number of sections       */
    char f_timdat[4];   /* time & date stamp        */
    char f_symptr[4];   /* file pointer to symtab   */
    char f_nsyms[4];    /* number of symtab entries */
    char f_opthdr[2];   /* sizeof(optional hdr)     */
    char f_flags[2];    /* flags            */
};

        /* IBM RS/6000 */
#define U802WRMAGIC     0730    /* writeable text segments **chh**      */
#define U802ROMAGIC     0735    /* readonly sharable text segments      */
#define U802TOCMAGIC    0737    /* readonly text segments and TOC       */

#define BADMAG(x)   \
    ((x).f_magic != U802ROMAGIC && (x).f_magic != U802WRMAGIC && \
     (x).f_magic != U802TOCMAGIC)

#define FILHDR  struct external_filehdr
#define FILHSZ  20


/********************** AOUT "OPTIONAL HEADER" **********************/


typedef struct
{
  unsigned char magic[2];   /* type of file         */
  unsigned char vstamp[2];  /* version stamp        */
  unsigned char tsize[4];   /* text size in bytes, padded to FW bdry */
  unsigned char dsize[4];   /* initialized data "  "    */
  unsigned char bsize[4];   /* uninitialized data "   " */
  unsigned char entry[4];   /* entry pt.            */
  unsigned char text_start[4];  /* base of text used for this file */
  unsigned char data_start[4];  /* base of data used for this file */
  unsigned char o_toc[4];   /* address of TOC */
  unsigned char o_snentry[2];   /* section number of entry point */
  unsigned char o_sntext[2];    /* section number of .text section */
  unsigned char o_sndata[2];    /* section number of .data section */
  unsigned char o_sntoc[2]; /* section number of TOC */
  unsigned char o_snloader[2];  /* section number of .loader section */
  unsigned char o_snbss[2]; /* section number of .bss section */
  unsigned char o_algntext[2];  /* .text alignment */
  unsigned char o_algndata[2];  /* .data alignment */
  unsigned char o_modtype[2];   /* module type (??) */
  unsigned char o_cputype[2];   /* cpu type */
  unsigned char o_maxstack[4];  /* max stack size (??) */
  unsigned char o_maxdata[4];   /* max data size (??) */
  unsigned char o_resv2[12];    /* reserved */
}
AOUTHDR;

#define AOUTSZ 72
#define SMALL_AOUTSZ (28)
#define AOUTHDRSZ 72

#define RS6K_AOUTHDR_OMAGIC 0x0107  /* old: text & data writeable */
#define RS6K_AOUTHDR_NMAGIC 0x0108  /* new: text r/o, data r/w */
#define RS6K_AOUTHDR_ZMAGIC 0x010B  /* paged: text r/o, both page-aligned */


/********************** SECTION HEADER **********************/


struct external_scnhdr {
    char        s_name[8];  /* section name         */
    char        s_paddr[4]; /* physical address, aliased s_nlib */
    char        s_vaddr[4]; /* virtual address      */
    char        s_size[4];  /* section size         */
    char        s_scnptr[4];    /* file ptr to raw data for section */
    char        s_relptr[4];    /* file ptr to relocation   */
    char        s_lnnoptr[4];   /* file ptr to line numbers */
    char        s_nreloc[2];    /* number of relocation entries */
    char        s_nlnno[2]; /* number of line number entries*/
    char        s_flags[4]; /* flags            */
};

/*
 * names of "special" sections
 */
#define _TEXT   ".text"
#define _DATA   ".data"
#define _BSS    ".bss"
#define _PAD    ".pad"
#define _LOADER ".loader"

#define SCNHDR  struct external_scnhdr
#define SCNHSZ  40

/* XCOFF uses a special .loader section with type STYP_LOADER.  */
#define STYP_LOADER 0x1000

/* XCOFF uses a special .debug section with type STYP_DEBUG.  */
#define STYP_DEBUG 0x2000

/* XCOFF handles line number or relocation overflow by creating
   another section header with STYP_OVRFLO set.  */
#define STYP_OVRFLO 0x8000

/********************** LINE NUMBERS **********************/

/* 1 line number entry for every "breakpointable" source line in a section.
 * Line numbers are grouped on a per function basis; first entry in a function
 * grouping will have l_lnno = 0 and in place of physical address will be the
 * symbol table index of the function name.
 */
struct external_lineno {
    union {
        char l_symndx[4];   /* function name symbol index, iff l_lnno == 0*/
        char l_paddr[4];    /* (physical) address of line number    */
    } l_addr;
    char l_lnno[2]; /* line number      */
};


#define LINENO  struct external_lineno
#define LINESZ  6


/********************** SYMBOLS **********************/

#define E_SYMNMLEN  8   /* # characters in a symbol name    */
#define E_FILNMLEN  14  /* # characters in a file name      */
#define E_DIMNUM    4   /* # array dimensions in auxiliary entry */

struct external_syment
{
  union {
    char e_name[E_SYMNMLEN];
    struct {
      char e_zeroes[4];
      char e_offset[4];
    } e;
  } e;
  char e_value[4];
  char e_scnum[2];
  char e_type[2];
  char e_sclass[1];
  char e_numaux[1];
};



#define N_BTMASK    (017)
#define N_TMASK     (060)
#define N_BTSHFT    (4)
#define N_TSHIFT    (2)


union external_auxent {
    struct {
        char x_tagndx[4];   /* str, un, or enum tag indx */
        union {
            struct {
                char  x_lnno[2]; /* declaration line number */
                char  x_size[2]; /* str/union/array size */
            } x_lnsz;
            char x_fsize[4];    /* size of function */
        } x_misc;
        union {
            struct {        /* if ISFCN, tag, or .bb */
                char x_lnnoptr[4];  /* ptr to fcn line # */
                char x_endndx[4];   /* entry ndx past block end */
            } x_fcn;
            struct {        /* if ISARY, up to 4 dimen. */
                char x_dimen[E_DIMNUM][2];
            } x_ary;
        } x_fcnary;
        char x_tvndx[2];        /* tv index */
    } x_sym;

    union {
        char x_fname[E_FILNMLEN];
        struct {
            char x_zeroes[4];
            char x_offset[4];
        } x_n;
    } x_file;

    struct {
        char x_scnlen[4];           /* section length */
        char x_nreloc[2];   /* # relocation entries */
        char x_nlinno[2];   /* # line numbers */
    } x_scn;

        struct {
        char x_tvfill[4];   /* tv fill value */
        char x_tvlen[2];    /* length of .tv */
        char x_tvran[2][2]; /* tv range */
    } x_tv;     /* info about .tv section (in auxent of symbol .tv)) */

    struct {
        unsigned char x_scnlen[4];
        unsigned char x_parmhash[4];
        unsigned char x_snhash[2];
        unsigned char x_smtyp[1];
        unsigned char x_smclas[1];
        unsigned char x_stab[4];
        unsigned char x_snstab[2];
    } x_csect;

};

#define SYMENT  struct external_syment
#define SYMESZ  18
#define AUXENT  union external_auxent
#define AUXESZ  18
#define DBXMASK 0x80        /* for dbx storage mask */
#define SYMNAME_IN_DEBUG(symptr) ((symptr)->n_sclass & DBXMASK)



/********************** RELOCATION DIRECTIVES **********************/


struct external_reloc {
  char r_vaddr[4];
  char r_symndx[4];
  char r_size[1];
  char r_type[1];
};


#define RELOC struct external_reloc
#define RELSZ 10

#define DEFAULT_DATA_SECTION_ALIGNMENT 4
#define DEFAULT_BSS_SECTION_ALIGNMENT 4
#define DEFAULT_TEXT_SECTION_ALIGNMENT 4
/* For new sections we havn't heard of before */
#define DEFAULT_SECTION_ALIGNMENT 4