gcc/config/i386/gas.h

   1 /* Definitions for Intel 386 using GAS.
   2    Copyright (C) 1988, 1993, 1994, 1996, 2002, 2004
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 /* Note that i386/seq-gas.h is a GAS configuration that does not use this
  23    file.  */
  24
  25 /* Use the bsd assembler syntax.  */
  26 /* we need to do this because gas is really a bsd style assembler,
  27  * and so doesn't work well this these att-isms:
  28  *
  29  *  ASM_OUTPUT_SKIP is .set .,.+N, which isn't implemented in gas
  30  *  ASM_OUTPUT_LOCAL is done with .set .,.+N, but that can't be
  31  *   used to define bss static space
  32  *
  33  * Next is the question of whether to uses underscores.  RMS didn't
  34  * like this idea at first, but since it is now obvious that we
  35  * need this separate tm file for use with gas, at least to get
  36  * dbx debugging info, I think we should also switch to underscores.
  37  * We can keep i386v for real att style output, and the few
  38  * people who want both form will have to compile twice.
  39  */
  40
  41 /* these come from i386/bsd.h, but are specific to sequent */
  42 #undef DBX_NO_XREFS
  43 #undef DBX_CONTIN_LENGTH
  44
  45 /* Ask for COFF symbols.  */
  46
  47 #define SDB_DEBUGGING_INFO 1
  48
  49 /* Output #ident as a .ident.  */
  50
  51 #define ASM_OUTPUT_IDENT(FILE, NAME) fprintf (FILE, "\t.ident \"%s\"\n", NAME);
  52
  53 /* In the past there was confusion as to what the argument to .align was
  54    in GAS.  For the last several years the rule has been this: for a.out
  55    file formats that argument is LOG, and for all other file formats the
  56    argument is 1<<LOG.
  57
  58    However, GAS now has .p2align and .balign pseudo-ops so to remove any
  59    doubt or guess work, and since this file is used for both a.out and other
  60    file formats, we use one of them.  */
  61
  62 #ifdef HAVE_GAS_BALIGN_AND_P2ALIGN
  63 #undef ASM_OUTPUT_ALIGN
  64 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
  65   if ((LOG)!=0) fprintf ((FILE), "\t.balign %d\n", 1<<(LOG))
  66 #endif
  67
  68 /* A C statement to output to the stdio stream FILE an assembler
  69    command to advance the location counter to a multiple of 1<<LOG
  70    bytes if it is within MAX_SKIP bytes.
  71
  72    This is used to align code labels according to Intel recommendations.  */
  73
  74 #ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
  75 #  define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
  76      if ((LOG) != 0) {\
  77        if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
  78        else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
  79      }
  80 #endif
  81 \f
  82 /* A C statement or statements which output an assembler instruction
  83    opcode to the stdio stream STREAM.  The macro-operand PTR is a
  84    variable of type `char *' which points to the opcode name in its
  85    "internal" form--the form that is written in the machine description.
  86
  87    GAS version 1.38.1 doesn't understand the `repz' opcode mnemonic.
  88    So use `repe' instead.  */
  89
  90 #define ASM_OUTPUT_OPCODE(STREAM, PTR)  \
  91 {                                                                       \
  92   if ((PTR)[0] == 'r'                                                   \
  93       && (PTR)[1] == 'e'                                                \
  94       && (PTR)[2] == 'p')                                               \
  95     {                                                                   \
  96       if ((PTR)[3] == 'z')                                              \
  97         {                                                               \
  98           fprintf (STREAM, "repe");                                     \
  99           (PTR) += 4;                                                   \
 100         }                                                               \
 101       else if ((PTR)[3] == 'n' && (PTR)[4] == 'z')                      \
 102         {                                                               \
 103           fprintf (STREAM, "repne");                                    \
 104           (PTR) += 5;                                                   \
 105         }                                                               \
 106     }                                                                   \
 107 }
 108
 109 /* Define macro used to output shift-double opcodes when the shift
 110    count is in %cl.  Some assemblers require %cl as an argument;
 111    some don't.
 112
 113    GAS requires the %cl argument, so override i386/unix.h.  */
 114
 115 #undef SHIFT_DOUBLE_OMITS_COUNT
 116 #define SHIFT_DOUBLE_OMITS_COUNT 0
 117
 118 /* Print opcodes the way that GAS expects them.  */
 119 #define GAS_MNEMONICS 1
 120
 121 /* The comment-starter string as GAS expects it. */
 122 #undef ASM_COMMENT_START
 123 #define ASM_COMMENT_START "#"
 124
 125 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE true