gcc/config/m68k/m68kemb.h

   1 /* Definitions of target machine for GNU compiler.  "embedded" 68XXX.
   2    This is meant to be included after m68k.h.
   3    Copyright (C) 1994, 1995, 1998, 1999 Free Software Foundation, Inc.  */
   4
   5 #define PTRDIFF_TYPE "long int"
   6 #define SIZE_TYPE "long unsigned int"
   7
   8 /* In order for bitfields to work on a 68000, or with -mnobitfield, we must
   9    define either PCC_BITFIELD_TYPE_MATTERS or STRUCTURE_SIZE_BOUNDARY.
  10    Defining STRUCTURE_SIZE_BOUNDARY results in structure packing problems,
  11    so we define PCC_BITFIELD_TYPE_MATTERS.  */
  12 #define PCC_BITFIELD_TYPE_MATTERS 1
  13
  14 /* Undef PCC_STATIC_STRUCT_RETURN so that we get a re-entrant calling
  15    convention.  */
  16 #undef PCC_STATIC_STRUCT_RETURN
  17
  18 /* Don't default to pcc-struct-return, so that we can return small structures
  19    and unions in registers, which is slightly more efficient.  */
  20 #define DEFAULT_PCC_STRUCT_RETURN 0
  21
  22 /* Return floating point values in a fp register.  This make fp code a
  23    little bit faster.  It also makes -msoft-float code incompatible with
  24    -m68881 code, so people have to be careful not to mix the two.  */
  25 #undef FUNCTION_VALUE
  26 #define FUNCTION_VALUE(VALTYPE,FUNC) LIBCALL_VALUE (TYPE_MODE (VALTYPE))
  27
  28 #undef LIBCALL_VALUE
  29 #define LIBCALL_VALUE(MODE)                                     \
  30  gen_rtx_REG ((MODE),                                           \
  31               ((TARGET_68881                                    \
  32                 && ((MODE) == SFmode || (MODE) == DFmode        \
  33                     || (MODE) == XFmode))                       \
  34            ? 16 : 0))
  35
  36 #undef FUNCTION_VALUE_REGNO_P
  37 #define FUNCTION_VALUE_REGNO_P(N) ((N) == 0 || (TARGET_68881 && (N) == 16))
  38
  39 #undef NEEDS_UNTYPED_CALL
  40 #define NEEDS_UNTYPED_CALL 1
  41
  42 #undef CPP_PREDEFINES
  43 #define CPP_PREDEFINES "-Dmc68000 -D__embedded__ -Asystem(embedded) \
  44   -Amachine(mc68000)"
  45
  46 /* Override the default LIB_SPEC from gcc.c.  We don't currently support
  47    profiling, or libg.a.  */
  48
  49 #undef  LIB_SPEC
  50 #define LIB_SPEC "-lc"
  51
  52 /* Make this be null, since we want the crt0.o to come from the linker
  53    script */
  54
  55 #undef  STARTFILE_SPEC
  56 #define STARTFILE_SPEC ""