gcc/config/i386/next.h

   1 /* Target definitions for GNU compiler for Intel x86 CPU running NeXTSTEP
   2    Copyright (C) 1993, 1995, 1996, 1999 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 #include "i386/gas.h"
  22 #include "nextstep.h"
  23
  24 /* By default, target has a 80387, with IEEE FP.  */
  25
  26 #undef  TARGET_SUBTARGET_DEFAULT
  27 #define TARGET_SUBTARGET_DEFAULT  (MASK_80387 | MASK_IEEE_FP)
  28
  29 /* Implicit library calls should use memcpy, not bcopy, etc.  */
  30
  31 #define TARGET_MEM_FUNCTIONS
  32
  33 /* Machines that use the AT&T assembler syntax
  34    also return floating point values in an FP register.
  35    Define how to find the value returned by a function.
  36    VALTYPE is the data type of the value (as a tree).
  37    If the precise function being called is known, FUNC is its FUNCTION_DECL;
  38    otherwise, FUNC is 0.  */
  39
  40 #undef  VALUE_REGNO
  41 #define VALUE_REGNO(MODE) \
  42   ((MODE) == SFmode || (MODE) == DFmode || (MODE) == XFmode     \
  43    ? FIRST_FLOAT_REG : 0)
  44
  45 /* A C statement or statements which output an assembler instruction
  46    opcode to the stdio stream STREAM.  The macro-operand PTR is a
  47    variable of type `char *' which points to the opcode name in its
  48    "internal" form--the form that is written in the machine description.
  49
  50    GAS version 1.38.1 doesn't understand the `repz' opcode mnemonic.
  51    So use `repe' instead.  */
  52
  53 #undef  ASM_OUTPUT_OPCODE
  54 #define ASM_OUTPUT_OPCODE(STREAM, PTR)  \
  55 {                                                       \
  56   if ((PTR)[0] == 'r'                                   \
  57       && (PTR)[1] == 'e'                                \
  58       && (PTR)[2] == 'p')                               \
  59     {                                                   \
  60       if ((PTR)[3] == 'z')                              \
  61         {                                               \
  62           fprintf (STREAM, "repe");                     \
  63           (PTR) += 4;                                   \
  64         }                                               \
  65       else if ((PTR)[3] == 'n' && (PTR)[4] == 'z')      \
  66         {                                               \
  67           fprintf (STREAM, "repne");                    \
  68           (PTR) += 5;                                   \
  69         }                                               \
  70     }                                                   \
  71 }
  72
  73 /* Define macro used to output shift-double opcodes when the shift
  74    count is in %cl.  Some assemblers require %cl as an argument;
  75    some don't.
  76
  77    GAS requires the %cl argument, so override unx386.h.  */
  78
  79 #undef  SHIFT_DOUBLE_OMITS_COUNT
  80 #define SHIFT_DOUBLE_OMITS_COUNT 0
  81
  82 /* Print opcodes the way that GAS expects them.  */
  83 #define GAS_MNEMONICS 1
  84
  85 /* Names to predefine in the preprocessor for this target machine.  */
  86
  87 #undef  CPP_PREDEFINES
  88 #define CPP_PREDEFINES "-DNeXT -Dunix -D__MACH__ -D__LITTLE_ENDIAN__ \
  89   -D__ARCHITECTURE__=\"i386\" -Asystem=unix -Asystem=mach"
  90
  91 /* This accounts for the return pc and saved fp on the i386.  */
  92
  93 #define OBJC_FORWARDING_STACK_OFFSET 8
  94 #define OBJC_FORWARDING_MIN_OFFSET 8
  95
  96 /* We do not want a dot in internal labels.  */
  97
  98 #undef LPREFIX
  99 #define LPREFIX "L"
 100
 101 #undef  ASM_GENERATE_INTERNAL_LABEL
 102 #define ASM_GENERATE_INTERNAL_LABEL(BUF,PREFIX,NUMBER)  \
 103     sprintf ((BUF), "*%s%ld", (PREFIX), (long)(NUMBER))
 104
 105 #undef ASM_OUTPUT_INTERNAL_LABEL
 106 #define ASM_OUTPUT_INTERNAL_LABEL(FILE,PREFIX,NUM)      \
 107   fprintf (FILE, "%s%d:\n", PREFIX, NUM)
 108
 109 /* Output to assembler file text saying following lines
 110    may contain character constants, extra white space, comments, etc.  */
 111
 112 #undef  ASM_APP_ON
 113 #define ASM_APP_ON "#APP\n"
 114
 115 /* Output to assembler file text saying following lines
 116    no longer contain unusual constructs.  */
 117
 118 #undef  ASM_APP_OFF
 119 #define ASM_APP_OFF "#NO_APP\n"
 120
 121 #undef  ASM_OUTPUT_REG_PUSH
 122 #define ASM_OUTPUT_REG_PUSH(FILE,REGNO)  \
 123   fprintf (FILE, "\tpushl %se%s\n", "%", reg_names[REGNO])
 124
 125 #undef  ASM_OUTPUT_REG_POP
 126 #define ASM_OUTPUT_REG_POP(FILE,REGNO)  \
 127   fprintf (FILE, "\tpopl %se%s\n", "%", reg_names[REGNO])
 128
 129 /* This is being overridden because the default i386 configuration
 130    generates calls to "_mcount".  NeXT system libraries all use
 131    "mcount".  */
 132
 133 #undef  FUNCTION_PROFILER
 134 #define FUNCTION_PROFILER(FILE, LABELNO)                                \
 135 {                                                                       \
 136   if (flag_pic)                                                         \
 137     {                                                                   \
 138       fprintf (FILE, "\tleal %sP%d@GOTOFF(%%ebx),%%edx\n",              \
 139                LPREFIX, (LABELNO));                                     \
 140       fprintf (FILE, "\tcall *mcount@GOT(%%ebx)\n");                    \
 141     }                                                                   \
 142   else                                                                  \
 143     {                                                                   \
 144       fprintf (FILE, "\tmovl $%sP%d,%%edx\n", LPREFIX, (LABELNO));      \
 145       fprintf (FILE, "\tcall mcount\n");                                \
 146     }                                                                   \
 147 }
 148
 149 /* BEGIN Calling Convention CHANGES */
 150
 151 /* These changes violate the Intel/Unix ABI.  Specifically, they
 152    change the way that space for a block return value is passed to a
 153    function.  The ABI says that the pointer is passed on the stack.
 154    We change to pass the pointer in %ebx.  This makes the NeXT
 155    Objective-C forwarding mechanism possible to implement on an i386.  */
 156
 157 /* Do NOT pass address of structure values on the stack.  */
 158
 159 #undef  STRUCT_VALUE_INCOMING
 160 #undef  STRUCT_VALUE
 161
 162 /* Pass them in %ebx.  */
 163
 164 #undef  STRUCT_VALUE_REGNUM
 165 #define STRUCT_VALUE_REGNUM 3
 166
 167 /* Because we are passing the pointer in a register, we don't need to
 168    rely on the callee to pop it.  */
 169
 170 #undef  RETURN_POPS_ARGS
 171 #define RETURN_POPS_ARGS(FUNDECL,FUNTYPE,SIZE)                          \
 172   ((FUNDECL) && TREE_CODE (FUNDECL) == IDENTIFIER_NODE          \
 173    ? 0                                                          \
 174    : (TARGET_RTD                                                \
 175       && (TYPE_ARG_TYPES (FUNTYPE) == 0                         \
 176           || (TREE_VALUE (tree_last (TYPE_ARG_TYPES (FUNTYPE))) \
 177               == void_type_node))) ? (SIZE) : 0)
 178
 179 /* END Calling Convention CHANGES */
 180
 181 /* NeXT still uses old binutils that don't insert nops by default
 182    when the .align directive demands to insert extra space in the text
 183    segment.  */
 184 #undef ASM_OUTPUT_ALIGN
 185 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
 186   if ((LOG)!=0) fprintf ((FILE), "\t.align %d,0x90\n", (LOG))