gcc/config/i386/gas.h

   1 /* Definitions for Intel 386 using GAS.
   2    Copyright (C) 1988, 1993, 1994, 1996, 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* Note that i386/seq-gas.h is a GAS configuration that does not use this
  22    file.  */
  23
  24 /* Use the bsd assembler syntax.  */
  25 /* we need to do this because gas is really a bsd style assembler,
  26  * and so doesn't work well this these att-isms:
  27  *
  28  *  ASM_OUTPUT_SKIP is .set .,.+N, which isn't implemented in gas
  29  *  ASM_OUTPUT_LOCAL is done with .set .,.+N, but that can't be
  30  *   used to define bss static space
  31  *
  32  * Next is the question of whether to uses underscores.  RMS didn't
  33  * like this idea at first, but since it is now obvious that we
  34  * need this separate tm file for use with gas, at least to get
  35  * dbx debugging info, I think we should also switch to underscores.
  36  * We can keep i386v for real att style output, and the few
  37  * people who want both form will have to compile twice.
  38  */
  39
  40 /* these come from i386/bsd.h, but are specific to sequent */
  41 #undef DBX_NO_XREFS
  42 #undef DBX_CONTIN_LENGTH
  43
  44 /* Ask for COFF symbols.  */
  45
  46 #define SDB_DEBUGGING_INFO
  47
  48 /* Specify predefined symbols in preprocessor.  */
  49
  50 #define CPP_PREDEFINES "-Dunix"
  51 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE}"
  52
  53 /* Allow #sccs in preprocessor.  */
  54
  55 #define SCCS_DIRECTIVE
  56
  57 /* Output #ident as a .ident.  */
  58
  59 #define ASM_OUTPUT_IDENT(FILE, NAME) fprintf (FILE, "\t.ident \"%s\"\n", NAME);
  60
  61 /* Implicit library calls should use memcpy, not bcopy, etc.  */
  62
  63 #define TARGET_MEM_FUNCTIONS
  64
  65 /* In the past there was confusion as to what the argument to .align was
  66    in GAS.  For the last several years the rule has been this: for a.out
  67    file formats that argument is LOG, and for all other file formats the
  68    argument is 1<<LOG.
  69
  70    However, GAS now has .p2align and .balign pseudo-ops so to remove any
  71    doubt or guess work, and since this file is used for both a.out and other
  72    file formats, we use one of them.  */
  73
  74 #ifdef HAVE_GAS_BALIGN_AND_P2ALIGN
  75 #undef ASM_OUTPUT_ALIGN
  76 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
  77   if ((LOG)!=0) fprintf ((FILE), "\t.balign %d\n", 1<<(LOG))
  78 #endif
  79
  80 /* A C statement to output to the stdio stream FILE an assembler
  81    command to advance the location counter to a multiple of 1<<LOG
  82    bytes if it is within MAX_SKIP bytes.
  83
  84    This is used to align code labels according to Intel recommendations.  */
  85
  86 #ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
  87 #  define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
  88      if ((LOG) != 0) {\
  89        if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
  90        else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
  91      }
  92 #endif
  93 \f
  94 /* A C statement or statements which output an assembler instruction
  95    opcode to the stdio stream STREAM.  The macro-operand PTR is a
  96    variable of type `char *' which points to the opcode name in its
  97    "internal" form--the form that is written in the machine description.
  98
  99    GAS version 1.38.1 doesn't understand the `repz' opcode mnemonic.
 100    So use `repe' instead.  */
 101
 102 #define ASM_OUTPUT_OPCODE(STREAM, PTR)  \
 103 {                                                                       \
 104   if ((PTR)[0] == 'r'                                                   \
 105       && (PTR)[1] == 'e'                                                \
 106       && (PTR)[2] == 'p')                                               \
 107     {                                                                   \
 108       if ((PTR)[3] == 'z')                                              \
 109         {                                                               \
 110           fprintf (STREAM, "repe");                                     \
 111           (PTR) += 4;                                                   \
 112         }                                                               \
 113       else if ((PTR)[3] == 'n' && (PTR)[4] == 'z')                      \
 114         {                                                               \
 115           fprintf (STREAM, "repne");                                    \
 116           (PTR) += 5;                                                   \
 117         }                                                               \
 118     }                                                                   \
 119 }
 120
 121 /* Define macro used to output shift-double opcodes when the shift
 122    count is in %cl.  Some assemblers require %cl as an argument;
 123    some don't.
 124
 125    GAS requires the %cl argument, so override i386/unix.h.  */
 126
 127 #undef SHIFT_DOUBLE_OMITS_COUNT
 128 #define SHIFT_DOUBLE_OMITS_COUNT 0
 129
 130 /* Print opcodes the way that GAS expects them.  */
 131 #define GAS_MNEMONICS 1
 132
 133 /* Output at beginning of assembler file.  */
 134 /* The .file command should always begin the output.  */
 135 #undef ASM_FILE_START
 136 #define ASM_FILE_START(FILE)                                            \
 137   do {                                                                  \
 138         if (ix86_asm_dialect == ASM_INTEL)                              \
 139           fputs ("\t.intel_syntax\n", FILE);                            \
 140         output_file_directive (FILE, main_input_filename);              \
 141   } while (0)