tm-i386vgas.h

这是完整的gcc源代码

/* Definitions for Intel 386 running system V with gnu tools
   Copyright (C) 1988 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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 1, or (at your option)
any later version.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include "tm-i386.h"
/* Use the bsd assembler syntax.  */
/* we need to do this because gas is really a bsd style assembler,
 * and so doesn't work well this these att-isms:
 *
 *  ASM_OUTPUT_SKIP is .set .,.+N, which isn't implemented in gas
 *  ASM_OUTPUT_LOCAL is done with .set .,.+N, but that can't be
 *   used to define bss static space
 *
 * Next is the question of whether to uses underscores.  RMS didn't
 * like this idea at first, but since it is now obvious that we
 * need this separate tm file for use with gas, at least to get
 * dbx debugging info.  */

#include "tm-bsd386.h"

/* these come from tm-bsd386.h, but are specific to sequent */
#undef DBX_NO_XREFS
#undef DBX_CONTIN_LENGTH

/* By default, target has a 80387.  */

#define TARGET_DEFAULT 1

#if 0 /* These aren't right for GNU ld.  */
/* Use crt1.o as a startup file and crtn.o as a closing file.  */

#define STARTFILE_SPEC  \
  "%{pg:gcrt1.o%s}%{!pg:%{p:mcrt1.o%s}%{!p:crt1.o%s}}"

#define LIB_SPEC "%{p:-L/usr/lib/libp}%{pg:-L/usr/lib/libp} -lc crtn.o%s"
#endif

/* Specify predefined symbols in preprocessor.  */

#define CPP_PREDEFINES "-Dunix -Di386"

/* Allow #sccs in preprocessor.  */

#define SCCS_DIRECTIVE

/* Output #ident as a .ident.  */

#define ASM_OUTPUT_IDENT(FILE, NAME) fprintf (FILE, "\t.ident \"%s\"\n", NAME);

/* We do not want to output SDB debugging information.  */

#undef SDB_DEBUGGING_INFO

/* We want to output DBX debugging information.  */

#define DBX_DEBUGGING_INFO

/* Implicit library calls should use memcpy, not bcopy, etc.  */

#define TARGET_MEM_FUNCTIONS

/* Writing `int' for a bitfield forces int alignment for the structure.  */

#define PCC_BITFIELD_TYPE_MATTERS 1

#undef ASM_FILE_START
#define ASM_FILE_START(FILE) \
  fprintf (FILE, "\t.file\t\"%s\"\n", dump_base_name);

/* This is how to output a reference to a user-level label named NAME.  */
#undef ASM_OUTPUT_LABELREF
#define ASM_OUTPUT_LABELREF(FILE,NAME)	\
  fprintf (FILE, "_%s", NAME)

#if 0  /* People say gas uses the log as the arg to .align.  */
/* When using gas, .align N aligns to an N-byte boundary.  */

#undef ASM_OUTPUT_ALIGN
#define ASM_OUTPUT_ALIGN(FILE,LOG)	\
     if ((LOG)!=0) fprintf ((FILE), "\t.align %d\n", 1<<(LOG))
#endif

/* Align labels, etc. at 4-byte boundaries.  */

#define ASM_OUTPUT_ALIGN_CODE(FILE) \
     fprintf ((FILE), "\t.align 2\n");  /* Use log of 4 as arg.  */

#if 0
#define ASM_OUTPUT_ALIGN_CODE(FILE) \
     fprintf ((FILE), "\t.align 4\n");
#endif

/* Machines that use the AT&T assembler syntax
   also return floating point values in an FP register.  */
/* Define how to find the value returned by a function.
   VALTYPE is the data type of the value (as a tree).
   If the precise function being called is known, FUNC is its FUNCTION_DECL;
   otherwise, FUNC is 0.  */

#define VALUE_REGNO(MODE) \
  (((MODE)==SFmode || (MODE)==DFmode) ? FIRST_FLOAT_REG : 0)

/* 1 if N is a possible register number for a function value. */

#define FUNCTION_VALUE_REGNO_P(N) ((N) == 0 || (N)== FIRST_FLOAT_REG)