gas/config/tc-i960.h

   1 /* tc-i960.h - Basic 80960 instruction formats.
   2    Copyright (C) 1989-2014 Free Software Foundation, Inc.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as
   8    published by the Free Software Foundation; either version 3,
   9    or (at your option) any later version.
  10
  11    GAS is distributed in the hope that it will be useful, but
  12    WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  14    the GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GAS; see the file COPYING.  If not, write to the Free
  18    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  19    02110-1301, USA.  */
  20
  21 #ifndef TC_I960
  22 #define TC_I960 1
  23
  24 #ifdef OBJ_ELF
  25 #define TARGET_FORMAT "elf32-i960"
  26 #define TARGET_ARCH bfd_arch_i960
  27 #endif
  28
  29 #define TARGET_BYTES_BIG_ENDIAN 0
  30
  31 #define WORKING_DOT_WORD
  32
  33 /*
  34  * The 'COJ' instructions are actually COBR instructions with the 'b' in
  35  * the mnemonic replaced by a 'j';  they are ALWAYS "de-optimized" if necessary:
  36  * if the displacement will not fit in 13 bits, the assembler will replace them
  37  * with the corresponding compare and branch instructions.
  38  *
  39  * All of the 'MEMn' instructions are the same format; the 'n' in the name
  40  * indicates the default index scale factor (the size of the datum operated on).
  41  *
  42  * The FBRA formats are not actually an instruction format.  They are the
  43  * "convenience directives" for branching on floating-point comparisons,
  44  * each of which generates 2 instructions (a 'bno' and one other branch).
  45  *
  46  * The CALLJ format is not actually an instruction format.  It indicates that
  47  * the instruction generated (a CTRL-format 'call') should have its relocation
  48  * specially flagged for link-time replacement with a 'bal' or 'calls' if
  49  * appropriate.
  50  */
  51
  52 /* tailor gas */
  53 #define LOCAL_LABELS_FB 1
  54 #define BITFIELD_CONS_EXPRESSIONS
  55
  56 /* tailor the coff format */
  57 #define COFF_MAGIC                              I960ROMAGIC
  58 #define OBJ_COFF_MAX_AUXENTRIES                 (2)
  59
  60 /* MEANING OF 'n_other' in the symbol record.
  61  *
  62  * If non-zero, the 'n_other' fields indicates either a leaf procedure or
  63  * a system procedure, as follows:
  64  *
  65  *      1 <= n_other <= 32 :
  66  *              The symbol is the entry point to a system procedure.
  67  *              'n_value' is the address of the entry, as for any other
  68  *              procedure.  The system procedure number (which can be used in
  69  *              a 'calls' instruction) is (n_other-1).  These entries come from
  70  *              '.sysproc' directives.
  71  *
  72  *      n_other == N_CALLNAME
  73  *              the symbol is the 'call' entry point to a leaf procedure.
  74  *              The *next* symbol in the symbol table must be the corresponding
  75  *              'bal' entry point to the procedure (see following).  These
  76  *              entries come from '.leafproc' directives in which two different
  77  *              symbols are specified (the first one is represented here).
  78  *
  79  *
  80  *      n_other == N_BALNAME
  81  *              the symbol is the 'bal' entry point to a leaf procedure.
  82  *              These entries result from '.leafproc' directives in which only
  83  *              one symbol is specified, or in which the same symbol is
  84  *              specified twice.
  85  *
  86  * Note that an N_CALLNAME entry *must* have a corresponding N_BALNAME entry,
  87  * but not every N_BALNAME entry must have an N_CALLNAME entry.
  88  */
  89 #define N_CALLNAME      ((char)-1)
  90 #define N_BALNAME       ((char)-2)
  91
  92 /* i960 uses a custom relocation record.  */
  93
  94 /* let obj-aout.h know */
  95 #define CUSTOM_RELOC_FORMAT 1
  96 /* let aout_gnu.h know */
  97 #define N_RELOCATION_INFO_DECLARED 1
  98 struct relocation_info
  99   {
 100     int r_address;              /* File address of item to be relocated */
 101     unsigned
 102       r_index:24,               /* Index of symbol on which relocation is based*/
 103       r_pcrel:1,                /* 1 => relocate PC-relative; else absolute
 104                                  *      On i960, pc-relative implies 24-bit
 105                                  *      address, absolute implies 32-bit.
 106                                  */
 107       r_length:2,               /* Number of bytes to relocate:
 108                                  *      0 => 1 byte
 109                                  *      1 => 2 bytes
 110                                  *      2 => 4 bytes -- only value used for i960
 111                                  */
 112       r_extern:1, r_bsr:1,      /* Something for the GNU NS32K assembler */
 113       r_disp:1,                 /* Something for the GNU NS32K assembler */
 114       r_callj:1,                /* 1 if relocation target is an i960 'callj' */
 115       nuthin:1;                 /* Unused                               */
 116   };
 117
 118 /* No shared lib support, so we don't need to ensure externally
 119    visible symbols can be overridden.  */
 120 #define EXTERN_FORCE_RELOC 0
 121
 122 /* Makes no sense to use the difference of 2 arbitrary symbols
 123    as the target of a call instruction.  */
 124 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEG)  \
 125   ((FIX)->fx_tcbit                              \
 126    || ! SEG_NORMAL (SEG)                        \
 127    || TC_FORCE_RELOCATION (FIX))
 128
 129 /* reloc_callj() may replace a 'call' with a 'calls' or a
 130    'bal', in which cases it modifies *fixP as appropriate.
 131    In the case of a 'calls', no further work is required.  */
 132 extern int reloc_callj (struct fix *);
 133
 134 #define TC_FORCE_RELOCATION_ABS(FIX)            \
 135   (TC_FORCE_RELOCATION (FIX)                    \
 136    || reloc_callj (FIX))
 137
 138 #define TC_FORCE_RELOCATION_LOCAL(FIX)          \
 139   (!(FIX)->fx_pcrel                             \
 140    || TC_FORCE_RELOCATION (FIX)         \
 141    || reloc_callj (FIX))
 142
 143 #ifdef OBJ_COFF
 144
 145 /* We store the bal information in the sy_tc field.  */
 146 #define TC_SYMFIELD_TYPE symbolS *
 147
 148 #endif
 149
 150 extern int i960_validate_fix (struct fix *, segT);
 151 #define TC_VALIDATE_FIX(FIX,SEGTYPE,LABEL) \
 152         if (!i960_validate_fix (FIX, SEGTYPE)) goto LABEL
 153
 154 #define tc_fix_adjustable(FIX)          ((FIX)->fx_bsr == 0)
 155
 156 #ifndef OBJ_ELF
 157 /* Values passed to md_apply_fix sometimes include symbol values.  */
 158 #define MD_APPLY_SYM_VALUE(FIX) tc_fix_adjustable (FIX)
 159 #else
 160 /* Values passed to md_apply_fix don't include the symbol value.  */
 161 #define MD_APPLY_SYM_VALUE(FIX) 0
 162 #endif
 163
 164 extern void brtab_emit (void);
 165 #define md_end()        brtab_emit ()
 166
 167 extern void tc_set_bal_of_call (symbolS *, symbolS *);
 168
 169 extern struct symbol *tc_get_bal_of_call (symbolS *);
 170
 171 extern void i960_handle_align (struct frag *);
 172 #define HANDLE_ALIGN(FRAG)      i960_handle_align (FRAG)
 173 #define NO_RELOC -1
 174
 175 #define md_operand(x)
 176
 177 extern const struct relax_type md_relax_table[];
 178 #define TC_GENERIC_RELAX_TABLE md_relax_table
 179
 180 #define LINKER_RELAXING_SHRINKS_ONLY
 181
 182 #define TC_FIX_TYPE struct { unsigned bsr : 1; }
 183 #define fx_bsr tc_fix_data.bsr
 184 #define TC_INIT_FIX_DATA(F)     ((F)->tc_fix_data.bsr = 0)
 185
 186 #endif