gcc/config/mips/abi64.h

   1 /* Definitions of target machine for GNU compiler.  64 bit ABI support.
   2    Copyright (C) 1994, 1995, 1996, 1998, 1999, 2001, 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 /* Macros to implement the 64 bit ABI.  This file is meant to be included
  22    after mips.h.  */
  23
  24 #undef SUBTARGET_TARGET_OPTIONS
  25 #define SUBTARGET_TARGET_OPTIONS \
  26   { "abi=", &mips_abi_string,                                           \
  27       "Specify ABI to use"},
  28
  29 #undef STACK_BOUNDARY
  30 #define STACK_BOUNDARY \
  31   ((mips_abi == ABI_32 || mips_abi == ABI_O64 || mips_abi == ABI_EABI) \
  32    ? 64 : 128)
  33
  34 #undef MIPS_STACK_ALIGN
  35 #define MIPS_STACK_ALIGN(LOC)                                           \
  36   ((mips_abi == ABI_32 || mips_abi == ABI_O64 || mips_abi == ABI_EABI)  \
  37    ? ((LOC) + 7) & ~7                                                   \
  38    : ((LOC) + 15) & ~15)
  39
  40 #undef GP_ARG_LAST
  41 #define GP_ARG_LAST  ((mips_abi == ABI_32 || mips_abi == ABI_O64)       \
  42                       ? GP_REG_FIRST + 7 : GP_REG_FIRST + 11)
  43 #undef FP_ARG_LAST
  44 #define FP_ARG_LAST  ((mips_abi == ABI_32 || mips_abi == ABI_O64)       \
  45                       ? FP_REG_FIRST + 15 : FP_REG_FIRST + 19)
  46
  47 #undef SUBTARGET_CONDITIONAL_REGISTER_USAGE
  48 #define SUBTARGET_CONDITIONAL_REGISTER_USAGE \
  49 {                                                                       \
  50   /* fp20-23 are now caller saved.  */                                  \
  51   if (mips_abi == ABI_64)                                               \
  52     {                                                                   \
  53       int regno;                                                        \
  54       for (regno = FP_REG_FIRST + 20; regno < FP_REG_FIRST + 24; regno++) \
  55         call_really_used_regs[regno] = call_used_regs[regno] = 1;       \
  56     }                                                                   \
  57   /* odd registers from fp21 to fp31 are now caller saved.  */          \
  58   if (mips_abi == ABI_N32 || mips_abi == ABI_MEABI)                     \
  59     {                                                                   \
  60       int regno;                                                        \
  61       for (regno = FP_REG_FIRST + 21; regno <= FP_REG_FIRST + 31; regno+=2) \
  62         call_really_used_regs[regno] = call_used_regs[regno] = 1;       \
  63     }                                                                   \
  64 }
  65
  66 #undef MAX_ARGS_IN_REGISTERS
  67 #define MAX_ARGS_IN_REGISTERS ((mips_abi == ABI_32 || mips_abi == ABI_O64) \
  68                                ? 4 : 8)
  69
  70 #undef REG_PARM_STACK_SPACE
  71 #define REG_PARM_STACK_SPACE(FNDECL)                                     \
  72   ((mips_abi == ABI_32 || mips_abi == ABI_O64)                           \
  73    ? (MAX_ARGS_IN_REGISTERS*UNITS_PER_WORD) - FIRST_PARM_OFFSET (FNDECL) \
  74    : 0)
  75
  76 #define FUNCTION_ARG_PADDING(MODE, TYPE)                                \
  77   (! BYTES_BIG_ENDIAN                                                   \
  78    ? upward                                                             \
  79    : (((MODE) == BLKmode                                                \
  80        ? ((TYPE) && TREE_CODE (TYPE_SIZE (TYPE)) == INTEGER_CST         \
  81           && int_size_in_bytes (TYPE) < (PARM_BOUNDARY / BITS_PER_UNIT))\
  82        : (GET_MODE_BITSIZE (MODE) < PARM_BOUNDARY                       \
  83           && (mips_abi == ABI_32                                        \
  84               || mips_abi == ABI_O64                                    \
  85               || mips_abi == ABI_EABI                                   \
  86               || GET_MODE_CLASS (MODE) == MODE_INT)))                   \
  87       ? downward : upward))
  88
  89 /* Modified version of the macro in expr.h.  */
  90 #define MUST_PASS_IN_STACK(MODE,TYPE)                   \
  91   ((TYPE) != 0                                          \
  92    && (TREE_CODE (TYPE_SIZE (TYPE)) != INTEGER_CST      \
  93        || TREE_ADDRESSABLE (TYPE)                       \
  94        || ((MODE) == BLKmode                            \
  95            && mips_abi != ABI_32 && mips_abi != ABI_O64 \
  96            && ! ((TYPE) != 0 && TREE_CODE (TYPE_SIZE (TYPE)) == INTEGER_CST \
  97                  && 0 == (int_size_in_bytes (TYPE)      \
  98                           % (PARM_BOUNDARY / BITS_PER_UNIT))) \
  99            && (FUNCTION_ARG_PADDING (MODE, TYPE)        \
 100                == (BYTES_BIG_ENDIAN ? upward : downward)))))
 101
 102 #define STRICT_ARGUMENT_NAMING (mips_abi != ABI_32 && mips_abi != ABI_O64)
 103
 104 /* A C expression that indicates when an argument must be passed by
 105    reference.  If nonzero for an argument, a copy of that argument is
 106    made in memory and a pointer to the argument is passed instead of the
 107    argument itself.  The pointer is passed in whatever way is appropriate
 108    for passing a pointer to that type.  */
 109 #define FUNCTION_ARG_PASS_BY_REFERENCE(CUM, MODE, TYPE, NAMED)          \
 110   function_arg_pass_by_reference (&CUM, MODE, TYPE, NAMED)
 111
 112 /* A C expression that indicates when it is the called function's
 113    responsibility to make a copy of arguments passed by invisible
 114    reference.  Normally, the caller makes a copy and passes the
 115    address of the copy to the routine being called.  When
 116    FUNCTION_ARG_CALLEE_COPIES is defined and is nonzero, the caller
 117    does not make a copy.  Instead, it passes a pointer to the "live"
 118    value.  The called function must not modify this value.  If it can
 119    be determined that the value won't be modified, it need not make a
 120    copy; otherwise a copy must be made.  */
 121 #define FUNCTION_ARG_CALLEE_COPIES(CUM, MODE, TYPE, NAMED)              \
 122   (mips_abi == ABI_EABI && (NAMED)                                      \
 123    && FUNCTION_ARG_PASS_BY_REFERENCE (CUM, MODE, TYPE, NAMED))
 124
 125 /* ??? Unimplemented stuff follows.  */
 126
 127 /* ??? Add support for 16 byte/128 bit long doubles here when
 128    mips_abi != ABI32.  */
 129
 130 /* ??? Make main return zero if user did not specify return value.  */
 131
 132 /* ??? Add support for .interfaces section, so as to get linker warnings
 133    when stdarg functions called without prototype in scope?  */
 134
 135 /* ??? Could optimize structure passing by putting the right register rtx
 136    into the field decl, so that if we use the field, we can take the value from
 137    a register instead of from memory.  */