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      1 /* Definitions for Intel 386 using GAS.
      2    Copyright (C) 1988-2013 Free Software Foundation, Inc.
      3 
      4 This file is part of GCC.
      5 
      6 GCC 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 3, or (at your option)
      9 any later version.
     10 
     11 GCC 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 GCC; see the file COPYING3.  If not see
     18 <http://www.gnu.org/licenses/>.  */
     19 
     20 /* Note that i386/seq-gas.h is a GAS configuration that does not use this
     21    file.  */
     22 
     23 /* Use the bsd assembler syntax.  */
     24 /* we need to do this because gas is really a bsd style assembler,
     25  * and so doesn't work well this these att-isms:
     26  *
     27  *  ASM_OUTPUT_SKIP is .set .,.+N, which isn't implemented in gas
     28  *  ASM_OUTPUT_LOCAL is done with .set .,.+N, but that can't be
     29  *   used to define bss static space
     30  *
     31  * Next is the question of whether to uses underscores.  RMS didn't
     32  * like this idea at first, but since it is now obvious that we
     33  * need this separate tm file for use with gas, at least to get
     34  * dbx debugging info, I think we should also switch to underscores.
     35  * We can keep i386v for real att style output, and the few
     36  * people who want both form will have to compile twice.
     37  */
     38 
     39 /* these come from i386/bsd.h, but are specific to sequent */
     40 #undef DBX_NO_XREFS
     41 #undef DBX_CONTIN_LENGTH
     42 
     43 /* Ask for COFF symbols.  */
     44 
     45 #define SDB_DEBUGGING_INFO 1
     46 
     47 /* Output #ident as a .ident.  */
     48 
     49 #undef TARGET_ASM_OUTPUT_IDENT
     50 #define TARGET_ASM_OUTPUT_IDENT default_asm_output_ident_directive
     51 
     52 /* In the past there was confusion as to what the argument to .align was
     53    in GAS.  For the last several years the rule has been this: for a.out
     54    file formats that argument is LOG, and for all other file formats the
     55    argument is 1<<LOG.
     56 
     57    However, GAS now has .p2align and .balign pseudo-ops so to remove any
     58    doubt or guess work, and since this file is used for both a.out and other
     59    file formats, we use one of them.  */
     60 
     61 #ifdef HAVE_GAS_BALIGN_AND_P2ALIGN
     62 #undef ASM_OUTPUT_ALIGN
     63 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
     64   if ((LOG)!=0) fprintf ((FILE), "\t.balign %d\n", 1<<(LOG))
     65 #endif
     66 
     67 /* A C statement to output to the stdio stream FILE an assembler
     68    command to advance the location counter to a multiple of 1<<LOG
     69    bytes if it is within MAX_SKIP bytes.
     70 
     71    This is used to align code labels according to Intel recommendations.  */
     72 
     73 #ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
     74 #  define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
     75      if ((LOG) != 0) {\
     76        if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
     77        else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
     78      }
     79 #endif
     80 
     81 /* 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 #undef ASM_OUTPUT_OPCODE
     91 #define ASM_OUTPUT_OPCODE(STREAM, PTR)	\
     92 {									\
     93   if ((PTR)[0] == 'r'							\
     94       && (PTR)[1] == 'e'						\
     95       && (PTR)[2] == 'p')						\
     96     {									\
     97       if ((PTR)[3] == 'z')						\
     98 	{								\
     99 	  fputs ("repe", (STREAM));					\
    100 	  (PTR) += 4;							\
    101 	}								\
    102       else if ((PTR)[3] == 'n' && (PTR)[4] == 'z')			\
    103 	{								\
    104 	  fputs ("repne", (STREAM));					\
    105 	  (PTR) += 5;							\
    106 	}								\
    107     }									\
    108   else									\
    109     ASM_OUTPUT_AVX_PREFIX ((STREAM), (PTR));				\
    110 }
    111 
    112 /* Define macro used to output shift-double opcodes when the shift
    113    count is in %cl.  Some assemblers require %cl as an argument;
    114    some don't.
    115 
    116    GAS requires the %cl argument, so override i386/unix.h.  */
    117 
    118 #undef SHIFT_DOUBLE_OMITS_COUNT
    119 #define SHIFT_DOUBLE_OMITS_COUNT 0
    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
    126