gcc/config/mmix/mmix.h

   1 /* Definitions of target machine for GNU compiler, for MMIX.
   2    Copyright (C) 2000-2017 Free Software Foundation, Inc.
   3    Contributed by Hans-Peter Nilsson (hp@bitrange.com)
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_MMIX_H
  22 #define GCC_MMIX_H
  23
  24 /* First, some local helper macros.  Note that the "default" value of
  25    FIXED_REGISTERS, CALL_USED_REGISTERS, REG_ALLOC_ORDER and
  26    REG_CLASS_CONTENTS depend on these values.  */
  27 #define MMIX_RESERVED_GNU_ARG_0_REGNUM 231
  28 #define MMIX_FIRST_ARG_REGNUM \
  29   (TARGET_ABI_GNU ? MMIX_RESERVED_GNU_ARG_0_REGNUM : 16)
  30 #define MMIX_FIRST_INCOMING_ARG_REGNUM \
  31   (TARGET_ABI_GNU ? MMIX_RESERVED_GNU_ARG_0_REGNUM : 0)
  32 #define MMIX_MAX_ARGS_IN_REGS 16
  33
  34 /* FIXME: This one isn't fully implemented yet.  Return values larger than
  35    one register are passed by reference in MMIX_STRUCT_VALUE_REGNUM by the
  36    caller, except for return values of type "complex".  */
  37 #define MMIX_MAX_REGS_FOR_VALUE 16
  38 #define MMIX_RETURN_VALUE_REGNUM \
  39   (TARGET_ABI_GNU ? MMIX_RESERVED_GNU_ARG_0_REGNUM : 15)
  40 #define MMIX_OUTGOING_RETURN_VALUE_REGNUM \
  41   (TARGET_ABI_GNU ? MMIX_RESERVED_GNU_ARG_0_REGNUM : 0)
  42 #define MMIX_STRUCT_VALUE_REGNUM 251
  43 #define MMIX_STATIC_CHAIN_REGNUM 252
  44 #define MMIX_FRAME_POINTER_REGNUM 253
  45 #define MMIX_STACK_POINTER_REGNUM 254
  46 #define MMIX_LAST_GENERAL_REGISTER 255
  47 #define MMIX_INCOMING_RETURN_ADDRESS_REGNUM MMIX_rJ_REGNUM
  48 #define MMIX_HIMULT_REGNUM 258
  49 #define MMIX_REMAINDER_REGNUM MMIX_rR_REGNUM
  50 #define MMIX_ARG_POINTER_REGNUM 261
  51 #define MMIX_rO_REGNUM 262
  52 #define MMIX_LAST_STACK_REGISTER_REGNUM 31
  53
  54 /* Four registers; "ideally, these registers should be call-clobbered", so
  55    just grab a bunch of the common clobbered registers.  FIXME: Last
  56    registers of return-value should be used, with an error if there's a
  57    return-value (that collides in size).  */
  58 #define MMIX_EH_RETURN_DATA_REGNO_START (MMIX_STRUCT_VALUE_REGNUM - 4)
  59
  60 /* Try to keep the definitions from running away on their own.  */
  61 #if (MMIX_EH_RETURN_DATA_REGNO_START \
  62      != MMIX_RESERVED_GNU_ARG_0_REGNUM + MMIX_MAX_ARGS_IN_REGS)
  63  #error MMIX register definition inconsistency
  64 #endif
  65
  66 #if (MMIX_MAX_REGS_FOR_VALUE + MMIX_MAX_ARGS_IN_REGS > 32)
  67  #error MMIX parameters and return values bad, more than 32 registers
  68 #endif
  69
  70 /* This chosen as "a call-clobbered hard register that is otherwise
  71    untouched by the epilogue".  */
  72 #define MMIX_EH_RETURN_STACKADJ_REGNUM MMIX_STATIC_CHAIN_REGNUM
  73
  74 #define MMIX_FUNCTION_ARG_SIZE(MODE, TYPE) \
  75  ((MODE) != BLKmode ? GET_MODE_SIZE (MODE) : int_size_in_bytes (TYPE))
  76
  77 /* Per-function machine data.  This is normally an opaque type just
  78    defined and used in the tm.c file, but we need to see the definition in
  79    mmix.md too.  */
  80 struct GTY(()) machine_function
  81  {
  82    int has_landing_pad;
  83    int highest_saved_stack_register;
  84    int in_prologue;
  85  };
  86
  87 /* For these target macros, there is no generic documentation here.  You
  88    should read `Using and Porting GCC' for that.  Only comments specific
  89    to the MMIX target are here.
  90
  91    There are however references to the specific texinfo node (comments
  92    with "Node:"), so there should be little or nothing amiss.  Probably
  93    the opposite, since we don't have to care about old littering and
  94    soon outdated generic comments.  */
  95
  96 /* Node: Driver */
  97
  98 /* User symbols are in the same name-space as built-in symbols, but we
  99    don't need the built-in symbols, so remove those and instead apply
 100    stricter operand checking.  Don't warn when expanding insns.  */
 101 #define ASM_SPEC "-no-predefined-syms -x"
 102
 103 /* Pass on -mset-program-start=N and -mset-data-start=M to the linker.
 104    Provide default program start 0x100 unless -mno-set-program-start.
 105    Don't do this if linking relocatably, with -r.  For a final link,
 106    produce mmo, unless ELF is requested or when linking relocatably.  */
 107 #define LINK_SPEC \
 108  "%{mset-program-start=*:--defsym __.MMIX.start..text=%*}\
 109   %{mset-data-start=*:--defsym __.MMIX.start..data=%*}\
 110   %{!mset-program-start=*:\
 111     %{!mno-set-program-start:\
 112      %{!r:--defsym __.MMIX.start..text=0x100}}}\
 113   %{!melf:%{!r:-m mmo}}%{melf|r:-m elf64mmix}"
 114
 115 /* FIXME: There's no provision for profiling here.  */
 116 #define STARTFILE_SPEC  \
 117   "crti%O%s crtbegin%O%s"
 118
 119 #define ENDFILE_SPEC "crtend%O%s crtn%O%s"
 120
 121 /* Node: Run-time Target */
 122
 123 /* Define __LONG_MAX__, since we're advised not to change glimits.h.  */
 124 #define TARGET_CPU_CPP_BUILTINS()                               \
 125   do                                                            \
 126     {                                                           \
 127       builtin_define ("__mmix__");                              \
 128       builtin_define ("__MMIX__");                              \
 129       if (TARGET_ABI_GNU)                                       \
 130         builtin_define ("__MMIX_ABI_GNU__");                    \
 131       else                                                      \
 132         builtin_define ("__MMIX_ABI_MMIXWARE__");               \
 133     }                                                           \
 134   while (0)
 135
 136 #define TARGET_DEFAULT \
 137  (MASK_BRANCH_PREDICT | MASK_BASE_ADDRESSES | MASK_USE_RETURN_INSN)
 138
 139
 140 /* Node: Per-Function Data */
 141 #define INIT_EXPANDERS mmix_init_expanders ()
 142
 143
 144 /* Node: Storage Layout */
 145 /* I see no bit-field instructions.  Anyway, the common order is from low
 146    to high, as the power of two, hence little-endian.  */
 147 #define BITS_BIG_ENDIAN 0
 148 #define BYTES_BIG_ENDIAN 1
 149 #define WORDS_BIG_ENDIAN 1
 150 #define FLOAT_WORDS_BIG_ENDIAN 1
 151 #define UNITS_PER_WORD 8
 152
 153 /* We need to align everything to 64 bits that can affect the alignment
 154    of other types.  Since address N is interpreted in MMIX as (N modulo
 155    access_size), we must align.  */
 156 #define PARM_BOUNDARY 64
 157 #define STACK_BOUNDARY 64
 158 #define FUNCTION_BOUNDARY 32
 159 #define BIGGEST_ALIGNMENT 64
 160
 161 /* This one is only used in the ADA front end.  */
 162 #define MINIMUM_ATOMIC_ALIGNMENT 8
 163
 164 /* Copied from elfos.h.  */
 165 #define MAX_OFILE_ALIGNMENT (32768 * 8)
 166
 167 #define DATA_ABI_ALIGNMENT(TYPE, BASIC_ALIGN) \
 168  mmix_data_alignment (TYPE, BASIC_ALIGN)
 169
 170 #define CONSTANT_ALIGNMENT(CONSTANT, BASIC_ALIGN) \
 171  mmix_constant_alignment (CONSTANT, BASIC_ALIGN)
 172
 173 #define LOCAL_ALIGNMENT(TYPE, BASIC_ALIGN) \
 174  mmix_local_alignment (TYPE, BASIC_ALIGN)
 175
 176 /* Following other ports, this seems to most commonly be the word-size,
 177    so let's do that here too.  */
 178 #define EMPTY_FIELD_BOUNDARY 64
 179
 180 /* We chose to have this low solely for similarity with the alpha.  It has
 181    nothing to do with passing the tests dg/c99-scope-2 and
 182    execute/align-1.c.  Nothing.  Though the tests seem wrong.  Padding of
 183    the structure is automatically added to get alignment when needed if we
 184    set this to just byte-boundary.  */
 185 #define STRUCTURE_SIZE_BOUNDARY 8
 186
 187 /* The lower bits are ignored.  */
 188 #define STRICT_ALIGNMENT 1
 189
 190
 191 /* Node: Type Layout */
 192
 193 /* It might seem more natural to have 64-bit ints on a 64-bit machine,
 194    but then an occasional MMIX programmer needs to know how to put a lot
 195    of __attribute__ stuff to get to the 8, 16 and 32-bit modes rather
 196    than the "intuitive" char, short and int types.  */
 197 #define INT_TYPE_SIZE 32
 198 #define SHORT_TYPE_SIZE 16
 199 #define LONG_LONG_TYPE_SIZE 64
 200
 201 #define FLOAT_TYPE_SIZE 32
 202 #define DOUBLE_TYPE_SIZE 64
 203 #define LONG_DOUBLE_TYPE_SIZE 64
 204
 205 #define DEFAULT_SIGNED_CHAR 1
 206
 207
 208 /* Node: Register Basics */
 209 /* We tell GCC about all 256 general registers, and we also include
 210    rD, rE, rH, rJ, rR and rO (in that order) so we can describe what insns
 211    clobber them.  We use a faked register for the argument pointer.  It is
 212    always eliminated towards the frame-pointer or the stack-pointer, never
 213    output in assembly.  Any fixed register would do for this, like $255,
 214    but future debugging is easier when using a separate register.  It
 215    counts as a global register for pseudorandom reasons.  */
 216 #define FIRST_PSEUDO_REGISTER 263
 217
 218 /* We treat general registers with no assigned purpose as fixed.  The
 219    stack pointer, $254, is also fixed.  Register $255 is referred to as a
 220    temporary register in the MMIX papers, and used as such in mmixal, so
 221    it should not be used as a stack pointer.  We set it to fixed, and use
 222    it "manually" at times of despair.  */
 223 #define FIXED_REGISTERS \
 224  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
 225    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
 226    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 227    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 228    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 229    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 230    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 231    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 232    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 233    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 234    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 235    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 236    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 237    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 238    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 239    1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, \
 240    1, 1, 0, 0, 0, 1, 1 \
 241  }
 242
 243 /* General registers are fixed and therefore "historically" marked
 244    call-used.  (FIXME: This has changed).  Registers $15..$31 are
 245    call-clobbered; we'll put arguments in $16 and up, and we need $15 for
 246    the MMIX register-stack "hole".  */
 247 #define CALL_USED_REGISTERS \
 248  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, \
 249    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 250    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 251    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 252    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 253    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 254    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 255    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 256    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 257    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 258    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 259    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 260    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 261    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 262    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
 263    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, \
 264    1, 1, 1, 1, 1, 1, 1 \
 265  }
 266
 267 #define INCOMING_REGNO(OUT) mmix_opposite_regno (OUT, 0)
 268
 269 #define OUTGOING_REGNO(IN) mmix_opposite_regno (IN, 1)
 270
 271 /* Defining LOCAL_REGNO is necessary in presence of prologue/epilogue,
 272    else GCC will be confused that those registers aren't saved and
 273    restored.  */
 274 #define LOCAL_REGNO(REGNO) mmix_local_regno (REGNO)
 275
 276 /* Node: Allocation Order */
 277
 278 /* We should allocate registers from 0 to 31 by increasing number, because
 279    I think that's what people expect.  Beyond that, just use
 280    call-clobbered global registers first, then call-clobbered special
 281    registers.  Last, the fixed registers.  */
 282 #define MMIX_MMIXWARE_ABI_REG_ALLOC_ORDER       \
 283  { 0, 1, 2, 3, 4, 5, 6, 7,                      \
 284    8, 9, 10, 11, 12, 13, 14, 15,                \
 285    16, 17, 18, 19, 20, 21, 22, 23,              \
 286    24, 25, 26, 27, 28, 29, 30, 31,              \
 287                                                 \
 288    252, 251, 250, 249, 248, 247,                \
 289                                                 \
 290    253,                                         \
 291                                                 \
 292    258, 260, 259,                               \
 293                                                 \
 294    32, 33, 34, 35, 36, 37, 38, 39,              \
 295    40, 41, 42, 43, 44, 45, 46, 47,              \
 296    48, 49, 50, 51, 52, 53, 54, 55,              \
 297    56, 57, 58, 59, 60, 61, 62, 63,              \
 298    64, 65, 66, 67, 68, 69, 70, 71,              \
 299    72, 73, 74, 75, 76, 77, 78, 79,              \
 300    80, 81, 82, 83, 84, 85, 86, 87,              \
 301    88, 89, 90, 91, 92, 93, 94, 95,              \
 302    96, 97, 98, 99, 100, 101, 102, 103,          \
 303    104, 105, 106, 107, 108, 109, 110, 111,      \
 304    112, 113, 114, 115, 116, 117, 118, 119,      \
 305    120, 121, 122, 123, 124, 125, 126, 127,      \
 306    128, 129, 130, 131, 132, 133, 134, 135,      \
 307    136, 137, 138, 139, 140, 141, 142, 143,      \
 308    144, 145, 146, 147, 148, 149, 150, 151,      \
 309    152, 153, 154, 155, 156, 157, 158, 159,      \
 310    160, 161, 162, 163, 164, 165, 166, 167,      \
 311    168, 169, 170, 171, 172, 173, 174, 175,      \
 312    176, 177, 178, 179, 180, 181, 182, 183,      \
 313    184, 185, 186, 187, 188, 189, 190, 191,      \
 314    192, 193, 194, 195, 196, 197, 198, 199,      \
 315    200, 201, 202, 203, 204, 205, 206, 207,      \
 316    208, 209, 210, 211, 212, 213, 214, 215,      \
 317    216, 217, 218, 219, 220, 221, 222, 223,      \
 318    224, 225, 226, 227, 228, 229, 230, 231,      \
 319    232, 233, 234, 235, 236, 237, 238, 239,      \
 320    240, 241, 242, 243, 244, 245, 246,           \
 321                                                 \
 322    254, 255, 256, 257, 261, 262                 \
 323  }
 324
 325 /* As a convenience, we put this nearby, for ease of comparison.
 326    First, call-clobbered registers in reverse order of assignment as
 327    parameters (also the top ones; not because they're parameters, but
 328    for continuity).
 329
 330    Second, saved registers that go on the register-stack.
 331
 332    Third, special registers rH, rR and rJ.  They should not normally be
 333    allocated, but since they're call-clobbered, it is cheaper to use one
 334    of them than using a call-saved register for a call-clobbered use,
 335    assuming it is referenced a very limited number of times.  Other global
 336    and fixed registers come next; they are never allocated.  */
 337 #define MMIX_GNU_ABI_REG_ALLOC_ORDER            \
 338  { 252, 251, 250, 249, 248, 247, 246,           \
 339    245, 244, 243, 242, 241, 240, 239, 238,      \
 340    237, 236, 235, 234, 233, 232, 231,           \
 341                                                 \
 342    0, 1, 2, 3, 4, 5, 6, 7,                      \
 343    8, 9, 10, 11, 12, 13, 14, 15,                \
 344    16, 17, 18, 19, 20, 21, 22, 23,              \
 345    24, 25, 26, 27, 28, 29, 30, 31,              \
 346                                                 \
 347    253,                                         \
 348                                                 \
 349    258, 260, 259,                               \
 350                                                 \
 351    32, 33, 34, 35, 36, 37, 38, 39,              \
 352    40, 41, 42, 43, 44, 45, 46, 47,              \
 353    48, 49, 50, 51, 52, 53, 54, 55,              \
 354    56, 57, 58, 59, 60, 61, 62, 63,              \
 355    64, 65, 66, 67, 68, 69, 70, 71,              \
 356    72, 73, 74, 75, 76, 77, 78, 79,              \
 357    80, 81, 82, 83, 84, 85, 86, 87,              \
 358    88, 89, 90, 91, 92, 93, 94, 95,              \
 359    96, 97, 98, 99, 100, 101, 102, 103,          \
 360    104, 105, 106, 107, 108, 109, 110, 111,      \
 361    112, 113, 114, 115, 116, 117, 118, 119,      \
 362    120, 121, 122, 123, 124, 125, 126, 127,      \
 363    128, 129, 130, 131, 132, 133, 134, 135,      \
 364    136, 137, 138, 139, 140, 141, 142, 143,      \
 365    144, 145, 146, 147, 148, 149, 150, 151,      \
 366    152, 153, 154, 155, 156, 157, 158, 159,      \
 367    160, 161, 162, 163, 164, 165, 166, 167,      \
 368    168, 169, 170, 171, 172, 173, 174, 175,      \
 369    176, 177, 178, 179, 180, 181, 182, 183,      \
 370    184, 185, 186, 187, 188, 189, 190, 191,      \
 371    192, 193, 194, 195, 196, 197, 198, 199,      \
 372    200, 201, 202, 203, 204, 205, 206, 207,      \
 373    208, 209, 210, 211, 212, 213, 214, 215,      \
 374    216, 217, 218, 219, 220, 221, 222, 223,      \
 375    224, 225, 226, 227, 228, 229, 230,           \
 376                                                 \
 377    254, 255, 256, 257, 261, 262                 \
 378  }
 379
 380 /* The default one.  */
 381 #define REG_ALLOC_ORDER MMIX_MMIXWARE_ABI_REG_ALLOC_ORDER
 382
 383 /* Node: Values in Registers */
 384
 385 #define HARD_REGNO_NREGS(REGNO, MODE)                   \
 386    ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1)         \
 387     / UNITS_PER_WORD)
 388
 389 /* Note that no register can really be accessed in single-float mode, so
 390    we *can* say 1 here.  FIXME:  Will TRT happen for single-float, or do
 391    we have to punt to libgcc1.asm?  */
 392 #define MODES_TIEABLE_P(MODE1, MODE2) 1
 393
 394
 395 /* Node: Leaf Functions */
 396 /* (empty) */
 397
 398
 399 /* Node: Register Classes */
 400
 401 enum reg_class
 402  {
 403    NO_REGS, GENERAL_REGS, REMAINDER_REG, HIMULT_REG,
 404    SYSTEM_REGS, ALL_REGS, LIM_REG_CLASSES
 405  };
 406
 407 #define N_REG_CLASSES (int) LIM_REG_CLASSES
 408
 409 #define REG_CLASS_NAMES                                         \
 410  {"NO_REGS", "GENERAL_REGS", "REMAINDER_REG", "HIMULT_REG",     \
 411   "SYSTEM_REGS", "ALL_REGS"}
 412
 413 /* Note that the contents of each item is always 32 bits.  */
 414 #define REG_CLASS_CONTENTS                      \
 415  {{0, 0, 0, 0, 0, 0, 0, 0, 0},                  \
 416   {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x20},       \
 417   {0, 0, 0, 0, 0, 0, 0, 0, 0x10},               \
 418   {0, 0, 0, 0, 0, 0, 0, 0, 4},                  \
 419   {0, 0, 0, 0, 0, 0, 0, 0, 0x7f},               \
 420   {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x7f}}
 421
 422 #define REGNO_REG_CLASS(REGNO)                                  \
 423  ((REGNO) <= MMIX_LAST_GENERAL_REGISTER                         \
 424   || (REGNO) == MMIX_ARG_POINTER_REGNUM                         \
 425   ? GENERAL_REGS                                                \
 426   : (REGNO) == MMIX_REMAINDER_REGNUM ? REMAINDER_REG            \
 427   : (REGNO) == MMIX_HIMULT_REGNUM ? HIMULT_REG : SYSTEM_REGS)
 428
 429 #define BASE_REG_CLASS GENERAL_REGS
 430
 431 #define INDEX_REG_CLASS GENERAL_REGS
 432
 433 #define REGNO_OK_FOR_BASE_P(REGNO)                              \
 434  ((REGNO) <= MMIX_LAST_GENERAL_REGISTER                         \
 435   || (REGNO) == MMIX_ARG_POINTER_REGNUM                         \
 436   || (reg_renumber[REGNO] > 0                                   \
 437       && reg_renumber[REGNO] <= MMIX_LAST_GENERAL_REGISTER))
 438
 439 #define REGNO_OK_FOR_INDEX_P(REGNO) REGNO_OK_FOR_BASE_P (REGNO)
 440
 441 #define SECONDARY_INPUT_RELOAD_CLASS(CLASS, MODE, X) \
 442  mmix_secondary_reload_class (CLASS, MODE, X, 1)
 443
 444 #define SECONDARY_OUTPUT_RELOAD_CLASS(CLASS, MODE, X) \
 445  mmix_secondary_reload_class (CLASS, MODE, X, 0)
 446
 447 #define CLASS_MAX_NREGS(CLASS, MODE) HARD_REGNO_NREGS (CLASS, MODE)
 448
 449
 450 /* Node: Frame Layout */
 451
 452 #define STACK_GROWS_DOWNWARD 1
 453 #define FRAME_GROWS_DOWNWARD 1
 454
 455 #define STARTING_FRAME_OFFSET \
 456   mmix_starting_frame_offset ()
 457
 458 #define FIRST_PARM_OFFSET(FUNDECL) 0
 459
 460 #define DYNAMIC_CHAIN_ADDRESS(FRAMEADDR) \
 461  mmix_dynamic_chain_address (FRAMEADDR)
 462
 463 /* FIXME: It seems RETURN_ADDR_OFFSET is undocumented.  */
 464
 465 #define SETUP_FRAME_ADDRESSES() \
 466  mmix_setup_frame_addresses ()
 467
 468 #define RETURN_ADDR_RTX(COUNT, FRAME)           \
 469  mmix_return_addr_rtx (COUNT, FRAME)
 470
 471 /* It's in rJ before we store it somewhere.  */
 472 #define INCOMING_RETURN_ADDR_RTX \
 473  gen_rtx_REG (Pmode, MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
 474
 475 /* FIXME: This does not seem properly documented or cross-indexed.
 476    Nowhere except in the code does it say it *has* to be in the range
 477    0..255, or else it will be truncated.  That goes for the default too.  */
 478 #define DWARF_FRAME_RETURN_COLUMN \
 479  DWARF_FRAME_REGNUM (MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
 480
 481 /* No return address is stored there.  */
 482 #define INCOMING_FRAME_SP_OFFSET 0
 483
 484 /* Node: Stack Checking */
 485 /* (empty) */
 486
 487
 488 /* Node: Exception Handling */
 489
 490 #define EH_RETURN_DATA_REGNO(N) \
 491  mmix_eh_return_data_regno (N)
 492
 493 #define EH_RETURN_STACKADJ_RTX \
 494  mmix_eh_return_stackadj_rtx ()
 495
 496 #define EH_RETURN_HANDLER_RTX \
 497  mmix_eh_return_handler_rtx ()
 498
 499 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
 500  mmix_asm_preferred_eh_data_format (CODE, GLOBAL)
 501
 502 /* Node: Frame Registers */
 503 #define STACK_POINTER_REGNUM MMIX_STACK_POINTER_REGNUM
 504
 505 /* Perhaps we can use HARD_FRAME_POINTER_REGNUM and decide later on
 506    what register we want to use.  */
 507 #define FRAME_POINTER_REGNUM MMIX_FRAME_POINTER_REGNUM
 508 #define ARG_POINTER_REGNUM MMIX_ARG_POINTER_REGNUM
 509
 510 #define STATIC_CHAIN_REGNUM MMIX_STATIC_CHAIN_REGNUM
 511
 512
 513 /* Node: Elimination */
 514
 515 /* The frame-pointer is stored in a location that either counts to the
 516    offset of incoming parameters, or that counts to the offset of the
 517    frame, so we can't use a single offset.  We therefore eliminate those
 518    two separately.  */
 519 #define ELIMINABLE_REGS                         \
 520  {{ARG_POINTER_REGNUM, STACK_POINTER_REGNUM},   \
 521   {ARG_POINTER_REGNUM, FRAME_POINTER_REGNUM},   \
 522   {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}}
 523
 524 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
 525  (OFFSET) = mmix_initial_elimination_offset (FROM, TO)
 526
 527
 528 /* Node: Stack Arguments */
 529
 530 #define ACCUMULATE_OUTGOING_ARGS 1
 531
 532
 533 /* Node: Register Arguments */
 534
 535 typedef struct { int regs; int lib; } CUMULATIVE_ARGS;
 536
 537 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
 538  ((CUM).regs = 0, (CUM).lib = ((LIBNAME) != 0))
 539
 540 #define FUNCTION_ARG_REGNO_P(REGNO)             \
 541  mmix_function_arg_regno_p (REGNO, 0)
 542
 543
 544 /* Node: Caller Saves */
 545 /* (empty) */
 546
 547
 548 /* Node: Function Entry */
 549
 550 /* See mmix.c for TARGET_ASM_FUNCTION_PROLOGUE and
 551    TARGET_ASM_FUNCTION_EPILOGUE.  */
 552
 553 /* We need to say that the epilogue uses the return address, so the
 554    initial-value machinery restores it.  FIXME: Some targets
 555    conditionalize on "reload_completed &&".  Investigate difference.
 556    FIXME: Not needed if nonlocal_goto_stack_level.  */
 557 #define EPILOGUE_USES(REGNO) \
 558  ((REGNO) == MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
 559
 560 /* Node: Profiling */
 561 #define FUNCTION_PROFILER(FILE, LABELNO)        \
 562  mmix_function_profiler (FILE, LABELNO)
 563
 564 /* Node: Trampolines */
 565
 566 #define TRAMPOLINE_SIZE         (4*UNITS_PER_WORD)
 567 #define TRAMPOLINE_ALIGNMENT    BITS_PER_WORD
 568
 569 /* Node: Addressing Modes */
 570
 571 #define CONSTANT_ADDRESS_P(X) \
 572  mmix_constant_address_p (X)
 573
 574 #define MAX_REGS_PER_ADDRESS 2
 575
 576
 577 /* Node: Condition Code */
 578
 579 #define SELECT_CC_MODE(OP, X, Y)                \
 580  mmix_select_cc_mode (OP, X, Y)
 581
 582 /* A definition of CANONICALIZE_COMPARISON that changed LE and GT
 583    comparisons with -1 to LT and GE respectively, and LT, LTU, GE or GEU
 584    comparisons with 256 to 255 and LE, LEU, GT and GTU has been
 585    ineffective; the code path for performing the changes did not trig for
 586    neither the GCC testsuite nor ghostscript-6.52 nor Knuth's mmix.tar.gz
 587    itself (core GCC functionality supposedly handling it) with sources
 588    from 2002-06-06.  */
 589
 590 #define REVERSIBLE_CC_MODE(MODE)                \
 591  mmix_reversible_cc_mode (MODE)
 592
 593
 594 /* Node: Costs */
 595
 596 #define SLOW_BYTE_ACCESS 0
 597
 598
 599 /* Node: Sections */
 600
 601 /* This must be a constant string, since it's used in crtstuff.c.  */
 602 #define TEXT_SECTION_ASM_OP \
 603  "\t.text ! mmixal:= 9H LOC 8B"
 604
 605 /* FIXME: Not documented.  */
 606 #define DATA_SECTION_ASM_OP \
 607  mmix_data_section_asm_op ()
 608
 609 #define READONLY_DATA_SECTION_ASM_OP    "\t.section\t.rodata"
 610
 611 /* Node: PIC */
 612 /* (empty) */
 613
 614
 615 /* Node: File Framework */
 616
 617 /* While any other punctuation character but ";" would do, we prefer "%"
 618    or "!"; "!" is an unary operator and so will not be mistakenly included
 619    in correctly formed expressions.  The hash character adds mass; catches
 620    the eye.  We can't have it as a comment char by itself, since it's a
 621    hex-number prefix.  */
 622 #define ASM_COMMENT_START "!#"
 623
 624 /* These aren't currently functional.  We just keep them as markers.  */
 625 #define ASM_APP_ON "%APP\n"
 626 #define ASM_APP_OFF "%NO_APP\n"
 627
 628 #define OUTPUT_QUOTED_STRING(STREAM, STRING) \
 629  mmix_output_quoted_string (STREAM, STRING, strlen (STRING))
 630
 631 #define TARGET_ASM_NAMED_SECTION default_elf_asm_named_section
 632
 633 /* Node: Data Output */
 634
 635 #define ASM_OUTPUT_ASCII(STREAM, PTR, LEN) \
 636  mmix_asm_output_ascii (STREAM, PTR, LEN)
 637
 638 /* Node: Uninitialized Data */
 639
 640 #define ASM_OUTPUT_ALIGNED_COMMON(ST, N, S, A) \
 641  mmix_asm_output_aligned_common (ST, N, S, A)
 642
 643 #define ASM_OUTPUT_ALIGNED_LOCAL(ST, N, S, A) \
 644  mmix_asm_output_aligned_local (ST, N, S, A)
 645
 646
 647 /* Node: Label Output */
 648
 649 #define ASM_OUTPUT_LABEL(STREAM, NAME) \
 650  mmix_asm_output_label (STREAM, NAME)
 651
 652 #define ASM_OUTPUT_INTERNAL_LABEL(STREAM, NAME) \
 653  mmix_asm_output_internal_label (STREAM, NAME)
 654
 655 #define ASM_DECLARE_REGISTER_GLOBAL(STREAM, DECL, REGNO, NAME) \
 656  mmix_asm_declare_register_global (STREAM, DECL, REGNO, NAME)
 657
 658 #define GLOBAL_ASM_OP "\t.global "
 659
 660 #define ASM_WEAKEN_LABEL(STREAM, NAME) \
 661  mmix_asm_weaken_label (STREAM, NAME)
 662
 663 #define MAKE_DECL_ONE_ONLY(DECL) \
 664  mmix_make_decl_one_only (DECL)
 665
 666 #define ASM_OUTPUT_LABELREF(STREAM, NAME) \
 667  mmix_asm_output_labelref (STREAM, NAME)
 668
 669 /* We insert a ":" to disambiguate against user symbols like L5.  */
 670 #define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM) \
 671  sprintf (LABEL, "*%s:%ld", PREFIX, (long)(NUM))
 672
 673 /* Insert "::"; these are rarer than internal labels.  FIXME: Make sure no
 674    ":" is seen in the object file; we don't really want that mmixal
 675    feature visible there.  We don't want the default, which uses a dot;
 676    that'd be incompatible with mmixal.  */
 677 #define ASM_PN_FORMAT "%s::%lu"
 678
 679 #define ASM_OUTPUT_DEF(STREAM, NAME, VALUE) \
 680  mmix_asm_output_def (STREAM, NAME, VALUE)
 681
 682 /* Node: Macros for Initialization */
 683 /* We're compiling to ELF and linking to MMO; fundamental ELF features
 684    that GCC depend on are there.  */
 685
 686 /* These must be constant strings, since they're used in crtstuff.c.  */
 687 #define INIT_SECTION_ASM_OP "\t.section .init,\"ax\" ! mmixal-incompatible"
 688
 689 #define FINI_SECTION_ASM_OP "\t.section .fini,\"ax\" ! mmixal-incompatible"
 690
 691 #define OBJECT_FORMAT_ELF
 692
 693
 694 /* Node: Instruction Output */
 695
 696 /* The non-$ register names must be prefixed with ":", since they're
 697    affected by PREFIX.  We provide the non-colon names as additional
 698    names.  */
 699 #define REGISTER_NAMES                                                  \
 700  {"$0", "$1", "$2", "$3", "$4", "$5", "$6", "$7",                       \
 701   "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15",                 \
 702   "$16", "$17", "$18", "$19", "$20", "$21", "$22", "$23",               \
 703   "$24", "$25", "$26", "$27", "$28", "$29", "$30", "$31",               \
 704   "$32", "$33", "$34", "$35", "$36", "$37", "$38", "$39",               \
 705   "$40", "$41", "$42", "$43", "$44", "$45", "$46", "$47",               \
 706   "$48", "$49", "$50", "$51", "$52", "$53", "$54", "$55",               \
 707   "$56", "$57", "$58", "$59", "$60", "$61", "$62", "$63",               \
 708   "$64", "$65", "$66", "$67", "$68", "$69", "$70", "$71",               \
 709   "$72", "$73", "$74", "$75", "$76", "$77", "$78", "$79",               \
 710   "$80", "$81", "$82", "$83", "$84", "$85", "$86", "$87",               \
 711   "$88", "$89", "$90", "$91", "$92", "$93", "$94", "$95",               \
 712   "$96", "$97", "$98", "$99", "$100", "$101", "$102", "$103",           \
 713   "$104", "$105", "$106", "$107", "$108", "$109", "$110", "$111",       \
 714   "$112", "$113", "$114", "$115", "$116", "$117", "$118", "$119",       \
 715   "$120", "$121", "$122", "$123", "$124", "$125", "$126", "$127",       \
 716   "$128", "$129", "$130", "$131", "$132", "$133", "$134", "$135",       \
 717   "$136", "$137", "$138", "$139", "$140", "$141", "$142", "$143",       \
 718   "$144", "$145", "$146", "$147", "$148", "$149", "$150", "$151",       \
 719   "$152", "$153", "$154", "$155", "$156", "$157", "$158", "$159",       \
 720   "$160", "$161", "$162", "$163", "$164", "$165", "$166", "$167",       \
 721   "$168", "$169", "$170", "$171", "$172", "$173", "$174", "$175",       \
 722   "$176", "$177", "$178", "$179", "$180", "$181", "$182", "$183",       \
 723   "$184", "$185", "$186", "$187", "$188", "$189", "$190", "$191",       \
 724   "$192", "$193", "$194", "$195", "$196", "$197", "$198", "$199",       \
 725   "$200", "$201", "$202", "$203", "$204", "$205", "$206", "$207",       \
 726   "$208", "$209", "$210", "$211", "$212", "$213", "$214", "$215",       \
 727   "$216", "$217", "$218", "$219", "$220", "$221", "$222", "$223",       \
 728   "$224", "$225", "$226", "$227", "$228", "$229", "$230", "$231",       \
 729   "$232", "$233", "$234", "$235", "$236", "$237", "$238", "$239",       \
 730   "$240", "$241", "$242", "$243", "$244", "$245", "$246", "$247",       \
 731   "$248", "$249", "$250", "$251", "$252", "$253", "$254", "$255",       \
 732   ":rD",  ":rE",  ":rH",  ":rJ",  ":rR",  "ap_!BAD!", ":rO"}
 733
 734 #define ADDITIONAL_REGISTER_NAMES                       \
 735  {{"sp", 254}, {":sp", 254}, {"rD", 256}, {"rE", 257},  \
 736   {"rH", 258}, {"rJ", MMIX_rJ_REGNUM}, {"rO", MMIX_rO_REGNUM}}
 737
 738 #define ASM_OUTPUT_REG_PUSH(STREAM, REGNO) \
 739  mmix_asm_output_reg_push (STREAM, REGNO)
 740
 741 #define ASM_OUTPUT_REG_POP(STREAM, REGNO) \
 742  mmix_asm_output_reg_pop (STREAM, REGNO)
 743
 744
 745 /* Node: Dispatch Tables */
 746
 747 /* We define both types, since SImode is the better, but DImode the only
 748    possible for mmixal so that's the one actually used.  */
 749 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL) \
 750  mmix_asm_output_addr_diff_elt (STREAM, BODY, VALUE, REL)
 751
 752 #define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE) \
 753  mmix_asm_output_addr_vec_elt (STREAM, VALUE)
 754
 755
 756 /* Node: Exception Region Output */
 757 /* (empty) */
 758
 759 /* Node: Alignment Output */
 760
 761 #define ASM_OUTPUT_SKIP(STREAM, NBYTES) \
 762  mmix_asm_output_skip (STREAM, NBYTES)
 763
 764 #define ASM_OUTPUT_ALIGN(STREAM, POWER) \
 765  mmix_asm_output_align (STREAM, POWER)
 766
 767
 768 /* Node: All Debuggers */
 769
 770 #define DBX_REGISTER_NUMBER(REGNO) \
 771  mmix_dbx_register_number (REGNO)
 772
 773
 774 /* Node: DBX Options */
 775 /* (empty) */
 776 /* Node: DBX Hooks */
 777 /* (empty) */
 778 /* Node: File Names and DBX */
 779 /* (empty) */
 780
 781
 782 /* Node: SDB and DWARF */
 783 #define DWARF2_DEBUGGING_INFO 1
 784 #define DWARF2_ASM_LINE_DEBUG_INFO 1
 785
 786 /* Node: Misc */
 787
 788 /* There's no way to get a PC-relative offset into tables for SImode, so
 789    for the moment we have absolute entries in DImode.
 790    When we're going ELF, these should be SImode and 1.  */
 791 #define CASE_VECTOR_MODE DImode
 792 #define CASE_VECTOR_PC_RELATIVE 0
 793
 794 #define WORD_REGISTER_OPERATIONS 1
 795
 796 /* We have a choice, which makes this yet another parameter to tweak.  The
 797    gut feeling is currently that SIGN_EXTEND wins; "int" is more frequent
 798    than "unsigned int", and we have signed characters.  FIXME: measure.  */
 799 #define LOAD_EXTEND_OP(MODE) (TARGET_ZERO_EXTEND ? ZERO_EXTEND : SIGN_EXTEND)
 800
 801 #define MOVE_MAX 8
 802
 803 #define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC) 1
 804
 805 /* ??? MMIX allows a choice of STORE_FLAG_VALUE.  Revisit later,
 806    we don't have scc expanders yet.  */
 807
 808 #define Pmode DImode
 809
 810 #define FUNCTION_MODE QImode
 811
 812 #define NO_IMPLICIT_EXTERN_C
 813
 814 /* mmix-knuth-mmixware target has no support of C99 runtime */
 815 #undef TARGET_LIBC_HAS_FUNCTION
 816 #define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
 817
 818 /* These are checked.  */
 819 #define DOLLARS_IN_IDENTIFIERS 0
 820 #define NO_DOLLAR_IN_LABEL
 821 #define NO_DOT_IN_LABEL
 822
 823 #endif /* GCC_MMIX_H */
 824 /*
 825  * Local variables:
 826  * eval: (c-set-style "gnu")
 827  * indent-tabs-mode: t
 828  * End:
 829  */