diff options
Diffstat (limited to 'include/bout.h')
| -rw-r--r-- | include/bout.h | 267 |
1 files changed, 138 insertions, 129 deletions
diff --git a/include/bout.h b/include/bout.h index 8fc28cc..a69e280 100644 --- a/include/bout.h +++ b/include/bout.h @@ -1,79 +1,91 @@ -/* - * This file is a modified version of 'a.out.h'. It is to be used in all - * GNU tools modified to support the i80960 (or tools that operate on - * object files created by such tools). - * - * All i80960 development is done in a CROSS-DEVELOPMENT environment. I.e., - * object code is generated on, and executed under the direction of a symbolic - * debugger running on, a host system. We do not want to be subject to the - * vagaries of which host it is or whether it supports COFF or a.out format, - * or anything else. We DO want to: - * - * o always generate the same format object files, regardless of host. - * - * o have an 'a.out' header that we can modify for our own purposes - * (the 80960 is typically an embedded processor and may require - * enhanced linker support that the normal a.out.h header can't - * accommodate). - * - * As for byte-ordering, the following rules apply: - * - * o Text and data that is actually downloaded to the target is always - * in i80960 (little-endian) order. - * - * o All other numbers (in the header, symbols, relocation directives) - * are in host byte-order: object files CANNOT be lifted from a - * little-end host and used on a big-endian (or vice versa) without - * modification. - * ==> THIS IS NO LONGER TRUE USING BFD. WE CAN GENERATE ANY BYTE ORDER - * FOR THE HEADER, AND READ ANY BYTE ORDER. PREFERENCE WOULD BE TO - * USE LITTLE-ENDIAN BYTE ORDER THROUGHOUT, REGARDLESS OF HOST. <== - * - * o The downloader ('comm960') takes care to generate a pseudo-header - * with correct (i80960) byte-ordering before shipping text and data - * off to the NINDY monitor in the target systems. Symbols and - * relocation info are never sent to the target. - */ +/* This file is a modified version of 'a.out.h'. It is to be used in all + GNU tools modified to support the i80960 (or tools that operate on + object files created by such tools). + + Copyright 2001 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; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* All i80960 development is done in a CROSS-DEVELOPMENT environment. I.e., + object code is generated on, and executed under the direction of a symbolic + debugger running on, a host system. We do not want to be subject to the + vagaries of which host it is or whether it supports COFF or a.out format, + or anything else. We DO want to: + + o always generate the same format object files, regardless of host. + + o have an 'a.out' header that we can modify for our own purposes + (the 80960 is typically an embedded processor and may require + enhanced linker support that the normal a.out.h header can't + accommodate). + + As for byte-ordering, the following rules apply: + + o Text and data that is actually downloaded to the target is always + in i80960 (little-endian) order. + + o All other numbers (in the header, symbols, relocation directives) + are in host byte-order: object files CANNOT be lifted from a + little-end host and used on a big-endian (or vice versa) without + modification. + ==> THIS IS NO LONGER TRUE USING BFD. WE CAN GENERATE ANY BYTE ORDER + FOR THE HEADER, AND READ ANY BYTE ORDER. PREFERENCE WOULD BE TO + USE LITTLE-ENDIAN BYTE ORDER THROUGHOUT, REGARDLESS OF HOST. <== + + o The downloader ('comm960') takes care to generate a pseudo-header + with correct (i80960) byte-ordering before shipping text and data + off to the NINDY monitor in the target systems. Symbols and + relocation info are never sent to the target. */ #define BMAGIC 0415 /* We don't accept the following (see N_BADMAG macro). - * They're just here so GNU code will compile. - */ + They're just here so GNU code will compile. */ #define OMAGIC 0407 /* old impure format */ #define NMAGIC 0410 /* read-only text */ #define ZMAGIC 0413 /* demand load format */ /* FILE HEADER - * All 'lengths' are given as a number of bytes. - * All 'alignments' are for relinkable files only; an alignment of - * 'n' indicates the corresponding segment must begin at an - * address that is a multiple of (2**n). - */ -struct external_exec { - /* Standard stuff */ - unsigned char e_info[4]; /* Identifies this as a b.out file */ - unsigned char e_text[4]; /* Length of text */ - unsigned char e_data[4]; /* Length of data */ - unsigned char e_bss[4]; /* Length of uninitialized data area */ - unsigned char e_syms[4]; /* Length of symbol table */ - unsigned char e_entry[4]; /* Runtime start address */ - unsigned char e_trsize[4]; /* Length of text relocation info */ - unsigned char e_drsize[4]; /* Length of data relocation info */ + All 'lengths' are given as a number of bytes. + All 'alignments' are for relinkable files only; an alignment of + 'n' indicates the corresponding segment must begin at an + address that is a multiple of (2**n). */ +struct external_exec + { + /* Standard stuff */ + unsigned char e_info[4]; /* Identifies this as a b.out file */ + unsigned char e_text[4]; /* Length of text */ + unsigned char e_data[4]; /* Length of data */ + unsigned char e_bss[4]; /* Length of uninitialized data area */ + unsigned char e_syms[4]; /* Length of symbol table */ + unsigned char e_entry[4]; /* Runtime start address */ + unsigned char e_trsize[4]; /* Length of text relocation info */ + unsigned char e_drsize[4]; /* Length of data relocation info */ - /* Added for i960 */ - unsigned char e_tload[4]; /* Text runtime load address */ - unsigned char e_dload[4]; /* Data runtime load address */ - unsigned char e_talign[1]; /* Alignment of text segment */ - unsigned char e_dalign[1]; /* Alignment of data segment */ - unsigned char e_balign[1]; /* Alignment of bss segment */ - unsigned char e_relaxable[1]; /* Assembled with enough info to allow linker to relax */ -}; + /* Added for i960 */ + unsigned char e_tload[4]; /* Text runtime load address */ + unsigned char e_dload[4]; /* Data runtime load address */ + unsigned char e_talign[1]; /* Alignment of text segment */ + unsigned char e_dalign[1]; /* Alignment of data segment */ + unsigned char e_balign[1]; /* Alignment of bss segment */ + unsigned char e_relaxable[1];/* Assembled with enough info to allow linker to relax */ + }; #define EXEC_BYTES_SIZE (sizeof (struct external_exec)) /* These macros use the a_xxx field names, since they operate on the exec - structure after it's been byte-swapped and realigned on the host machine. */ + structure after it's been byte-swapped and realigned on the host machine. */ #define N_BADMAG(x) (((x).a_info)!=BMAGIC) #define N_TXTOFF(x) EXEC_BYTES_SIZE #define N_DATOFF(x) ( N_TXTOFF(x) + (x).a_text ) @@ -90,23 +102,24 @@ struct external_exec { #define N_TXTADDR(x) 0 #endif -/* A single entry in the symbol table - */ -struct nlist { - union { - char *n_name; - struct nlist *n_next; - long n_strx; /* Index into string table */ - } n_un; - unsigned char n_type; /* See below */ - char n_other; /* Used in i80960 support -- see below */ - short n_desc; - unsigned long n_value; -}; +/* A single entry in the symbol table. */ +struct nlist + { + union + { + char* n_name; + struct nlist * n_next; + long n_strx; /* Index into string table */ + } n_un; + + unsigned char n_type; /* See below */ + char n_other; /* Used in i80960 support -- see below */ + short n_desc; + unsigned long n_value; + }; -/* Legal values of n_type - */ +/* Legal values of n_type. */ #define N_UNDF 0 /* Undefined symbol */ #define N_ABS 2 /* Absolute symbol */ #define N_TEXT 4 /* Text symbol */ @@ -119,34 +132,33 @@ struct nlist { #define N_STAB 0340 /* Mask for all bits used for SDB entries */ /* MEANING OF 'n_other' - * - * If non-zero, the 'n_other' fields indicates either a leaf procedure or - * a system procedure, as follows: - * - * 1 <= n_other <= 32 : - * The symbol is the entry point to a system procedure. - * 'n_value' is the address of the entry, as for any other - * procedure. The system procedure number (which can be used in - * a 'calls' instruction) is (n_other-1). These entries come from - * '.sysproc' directives. - * - * n_other == N_CALLNAME - * the symbol is the 'call' entry point to a leaf procedure. - * The *next* symbol in the symbol table must be the corresponding - * 'bal' entry point to the procedure (see following). These - * entries come from '.leafproc' directives in which two different - * symbols are specified (the first one is represented here). - * - * - * n_other == N_BALNAME - * the symbol is the 'bal' entry point to a leaf procedure. - * These entries result from '.leafproc' directives in which only - * one symbol is specified, or in which the same symbol is - * specified twice. - * - * Note that an N_CALLNAME entry *must* have a corresponding N_BALNAME entry, - * but not every N_BALNAME entry must have an N_CALLNAME entry. - */ + + If non-zero, the 'n_other' fields indicates either a leaf procedure or + a system procedure, as follows: + + 1 <= n_other <= 32 : + The symbol is the entry point to a system procedure. + 'n_value' is the address of the entry, as for any other + procedure. The system procedure number (which can be used in + a 'calls' instruction) is (n_other-1). These entries come from + '.sysproc' directives. + + n_other == N_CALLNAME + the symbol is the 'call' entry point to a leaf procedure. + The *next* symbol in the symbol table must be the corresponding + 'bal' entry point to the procedure (see following). These + entries come from '.leafproc' directives in which two different + symbols are specified (the first one is represented here). + + + n_other == N_BALNAME + the symbol is the 'bal' entry point to a leaf procedure. + These entries result from '.leafproc' directives in which only + one symbol is specified, or in which the same symbol is + specified twice. + + Note that an N_CALLNAME entry *must* have a corresponding N_BALNAME entry, + but not every N_BALNAME entry must have an N_CALLNAME entry. */ #define N_CALLNAME ((char)-1) #define N_BALNAME ((char)-2) #define IS_CALLNAME(x) (N_CALLNAME == (x)) @@ -154,29 +166,26 @@ struct nlist { #define IS_OTHER(x) ((x)>0 && (x) <=32) #define b_out_relocation_info relocation_info -struct relocation_info { - int r_address; /* File address of item to be relocated */ - unsigned +struct relocation_info + { + int r_address; /* File address of item to be relocated. */ + unsigned #define r_index r_symbolnum - r_symbolnum:24,/* Index of symbol on which relocation is based, - * if r_extern is set. Otherwise set to - * either N_TEXT, N_DATA, or N_BSS to - * indicate section on which relocation is - * based. - */ - r_pcrel:1, /* 1 => relocate PC-relative; else absolute - * On i960, pc-relative implies 24-bit - * address, absolute implies 32-bit. - */ - r_length:2, /* Number of bytes to relocate: - * 0 => 1 byte - * 1 => 2 bytes -- used for 13 bit pcrel - * 2 => 4 bytes - */ - r_extern:1, - r_bsr:1, /* Something for the GNU NS32K assembler */ - r_disp:1, /* Something for the GNU NS32K assembler */ - r_callj:1, /* 1 if relocation target is an i960 'callj' */ - r_relaxable:1; /* 1 if enough info is left to relax - the data */ + r_symbolnum:24, /* Index of symbol on which relocation is based, + if r_extern is set. Otherwise set to + either N_TEXT, N_DATA, or N_BSS to + indicate section on which relocation is + based. */ + r_pcrel:1, /* 1 => relocate PC-relative; else absolute + On i960, pc-relative implies 24-bit + address, absolute implies 32-bit. */ + r_length:2, /* Number of bytes to relocate: + 0 => 1 byte + 1 => 2 bytes -- used for 13 bit pcrel + 2 => 4 bytes. */ + r_extern:1, + r_bsr:1, /* Something for the GNU NS32K assembler. */ + r_disp:1, /* Something for the GNU NS32K assembler. */ + r_callj:1, /* 1 if relocation target is an i960 'callj'. */ + r_relaxable:1; /* 1 if enough info is left to relax the data. */ }; |