1 /* Definitions of target machine for GNU compiler, for MMIX.
2    Copyright (C) 2000-2016 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 #define HARD_REGNO_MODE_OK(REGNO, MODE) 1
390 
391 /* Note that no register can really be accessed in single-float mode, so
392    we *can* say 1 here.  FIXME:  Will TRT happen for single-float, or do
393    we have to punt to libgcc1.asm?  */
394 #define MODES_TIEABLE_P(MODE1, MODE2) 1
395 
396 
397 /* Node: Leaf Functions */
398 /* (empty) */
399 
400 
401 /* Node: Register Classes */
402 
403 enum reg_class
404  {
405    NO_REGS, GENERAL_REGS, REMAINDER_REG, HIMULT_REG,
406    SYSTEM_REGS, ALL_REGS, LIM_REG_CLASSES
407  };
408 
409 #define N_REG_CLASSES (int) LIM_REG_CLASSES
410 
411 #define REG_CLASS_NAMES						\
412  {"NO_REGS", "GENERAL_REGS", "REMAINDER_REG", "HIMULT_REG",	\
413   "SYSTEM_REGS", "ALL_REGS"}
414 
415 /* Note that the contents of each item is always 32 bits.  */
416 #define REG_CLASS_CONTENTS			\
417  {{0, 0, 0, 0, 0, 0, 0, 0, 0},			\
418   {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x20},	\
419   {0, 0, 0, 0, 0, 0, 0, 0, 0x10},		\
420   {0, 0, 0, 0, 0, 0, 0, 0, 4},			\
421   {0, 0, 0, 0, 0, 0, 0, 0, 0x7f},		\
422   {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x7f}}
423 
424 #define REGNO_REG_CLASS(REGNO)					\
425  ((REGNO) <= MMIX_LAST_GENERAL_REGISTER				\
426   || (REGNO) == MMIX_ARG_POINTER_REGNUM				\
427   ? GENERAL_REGS						\
428   : (REGNO) == MMIX_REMAINDER_REGNUM ? REMAINDER_REG		\
429   : (REGNO) == MMIX_HIMULT_REGNUM ? HIMULT_REG : SYSTEM_REGS)
430 
431 #define BASE_REG_CLASS GENERAL_REGS
432 
433 #define INDEX_REG_CLASS GENERAL_REGS
434 
435 #define REGNO_OK_FOR_BASE_P(REGNO)				\
436  ((REGNO) <= MMIX_LAST_GENERAL_REGISTER				\
437   || (REGNO) == MMIX_ARG_POINTER_REGNUM				\
438   || (reg_renumber[REGNO] > 0					\
439       && reg_renumber[REGNO] <= MMIX_LAST_GENERAL_REGISTER))
440 
441 #define REGNO_OK_FOR_INDEX_P(REGNO) REGNO_OK_FOR_BASE_P (REGNO)
442 
443 #define SECONDARY_INPUT_RELOAD_CLASS(CLASS, MODE, X) \
444  mmix_secondary_reload_class (CLASS, MODE, X, 1)
445 
446 #define SECONDARY_OUTPUT_RELOAD_CLASS(CLASS, MODE, X) \
447  mmix_secondary_reload_class (CLASS, MODE, X, 0)
448 
449 #define CLASS_MAX_NREGS(CLASS, MODE) HARD_REGNO_NREGS (CLASS, MODE)
450 
451 
452 /* Node: Frame Layout */
453 
454 #define STACK_GROWS_DOWNWARD 1
455 #define FRAME_GROWS_DOWNWARD 1
456 
457 #define STARTING_FRAME_OFFSET \
458   mmix_starting_frame_offset ()
459 
460 #define FIRST_PARM_OFFSET(FUNDECL) 0
461 
462 #define DYNAMIC_CHAIN_ADDRESS(FRAMEADDR) \
463  mmix_dynamic_chain_address (FRAMEADDR)
464 
465 /* FIXME: It seems RETURN_ADDR_OFFSET is undocumented.  */
466 
467 #define SETUP_FRAME_ADDRESSES() \
468  mmix_setup_frame_addresses ()
469 
470 #define RETURN_ADDR_RTX(COUNT, FRAME)		\
471  mmix_return_addr_rtx (COUNT, FRAME)
472 
473 /* It's in rJ before we store it somewhere.  */
474 #define INCOMING_RETURN_ADDR_RTX \
475  gen_rtx_REG (Pmode, MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
476 
477 /* FIXME: This does not seem properly documented or cross-indexed.
478    Nowhere except in the code does it say it *has* to be in the range
479    0..255, or else it will be truncated.  That goes for the default too.  */
480 #define DWARF_FRAME_RETURN_COLUMN \
481  DWARF_FRAME_REGNUM (MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
482 
483 /* No return address is stored there.  */
484 #define INCOMING_FRAME_SP_OFFSET 0
485 
486 /* Node: Stack Checking */
487 /* (empty) */
488 
489 
490 /* Node: Exception Handling */
491 
492 #define EH_RETURN_DATA_REGNO(N) \
493  mmix_eh_return_data_regno (N)
494 
495 #define EH_RETURN_STACKADJ_RTX \
496  mmix_eh_return_stackadj_rtx ()
497 
498 #define EH_RETURN_HANDLER_RTX \
499  mmix_eh_return_handler_rtx ()
500 
501 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
502  mmix_asm_preferred_eh_data_format (CODE, GLOBAL)
503 
504 /* Node: Frame Registers */
505 #define STACK_POINTER_REGNUM MMIX_STACK_POINTER_REGNUM
506 
507 /* Perhaps we can use HARD_FRAME_POINTER_REGNUM and decide later on
508    what register we want to use.  */
509 #define FRAME_POINTER_REGNUM MMIX_FRAME_POINTER_REGNUM
510 #define ARG_POINTER_REGNUM MMIX_ARG_POINTER_REGNUM
511 
512 #define STATIC_CHAIN_REGNUM MMIX_STATIC_CHAIN_REGNUM
513 
514 
515 /* Node: Elimination */
516 
517 /* The frame-pointer is stored in a location that either counts to the
518    offset of incoming parameters, or that counts to the offset of the
519    frame, so we can't use a single offset.  We therefore eliminate those
520    two separately.  */
521 #define ELIMINABLE_REGS				\
522  {{ARG_POINTER_REGNUM, STACK_POINTER_REGNUM},	\
523   {ARG_POINTER_REGNUM, FRAME_POINTER_REGNUM},	\
524   {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}}
525 
526 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
527  (OFFSET) = mmix_initial_elimination_offset (FROM, TO)
528 
529 
530 /* Node: Stack Arguments */
531 
532 #define ACCUMULATE_OUTGOING_ARGS 1
533 
534 
535 /* Node: Register Arguments */
536 
537 typedef struct { int regs; int lib; } CUMULATIVE_ARGS;
538 
539 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
540  ((CUM).regs = 0, (CUM).lib = ((LIBNAME) != 0))
541 
542 #define FUNCTION_ARG_REGNO_P(REGNO)		\
543  mmix_function_arg_regno_p (REGNO, 0)
544 
545 
546 /* Node: Caller Saves */
547 /* (empty) */
548 
549 
550 /* Node: Function Entry */
551 
552 /* See mmix.c for TARGET_ASM_FUNCTION_PROLOGUE and
553    TARGET_ASM_FUNCTION_EPILOGUE.  */
554 
555 /* We need to say that the epilogue uses the return address, so the
556    initial-value machinery restores it.  FIXME: Some targets
557    conditionalize on "reload_completed &&".  Investigate difference.
558    FIXME: Not needed if nonlocal_goto_stack_level.  */
559 #define EPILOGUE_USES(REGNO) \
560  ((REGNO) == MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
561 
562 /* Node: Profiling */
563 #define FUNCTION_PROFILER(FILE, LABELNO)	\
564  mmix_function_profiler (FILE, LABELNO)
565 
566 /* Node: Trampolines */
567 
568 #define TRAMPOLINE_SIZE		(4*UNITS_PER_WORD)
569 #define TRAMPOLINE_ALIGNMENT	BITS_PER_WORD
570 
571 /* Node: Addressing Modes */
572 
573 #define CONSTANT_ADDRESS_P(X) \
574  mmix_constant_address_p (X)
575 
576 #define MAX_REGS_PER_ADDRESS 2
577 
578 
579 /* Node: Condition Code */
580 
581 #define SELECT_CC_MODE(OP, X, Y)		\
582  mmix_select_cc_mode (OP, X, Y)
583 
584 /* A definition of CANONICALIZE_COMPARISON that changed LE and GT
585    comparisons with -1 to LT and GE respectively, and LT, LTU, GE or GEU
586    comparisons with 256 to 255 and LE, LEU, GT and GTU has been
587    ineffective; the code path for performing the changes did not trig for
588    neither the GCC testsuite nor ghostscript-6.52 nor Knuth's mmix.tar.gz
589    itself (core GCC functionality supposedly handling it) with sources
590    from 2002-06-06.  */
591 
592 #define REVERSIBLE_CC_MODE(MODE)		\
593  mmix_reversible_cc_mode (MODE)
594 
595 
596 /* Node: Costs */
597 
598 #define SLOW_BYTE_ACCESS 0
599 
600 
601 /* Node: Sections */
602 
603 /* This must be a constant string, since it's used in crtstuff.c.  */
604 #define TEXT_SECTION_ASM_OP \
605  "\t.text ! mmixal:= 9H LOC 8B"
606 
607 /* FIXME: Not documented.  */
608 #define DATA_SECTION_ASM_OP \
609  mmix_data_section_asm_op ()
610 
611 #define READONLY_DATA_SECTION_ASM_OP	"\t.section\t.rodata"
612 
613 /* Node: PIC */
614 /* (empty) */
615 
616 
617 /* Node: File Framework */
618 
619 /* While any other punctuation character but ";" would do, we prefer "%"
620    or "!"; "!" is an unary operator and so will not be mistakenly included
621    in correctly formed expressions.  The hash character adds mass; catches
622    the eye.  We can't have it as a comment char by itself, since it's a
623    hex-number prefix.  */
624 #define ASM_COMMENT_START "!#"
625 
626 /* These aren't currently functional.  We just keep them as markers.  */
627 #define ASM_APP_ON "%APP\n"
628 #define ASM_APP_OFF "%NO_APP\n"
629 
630 #define OUTPUT_QUOTED_STRING(STREAM, STRING) \
631  mmix_output_quoted_string (STREAM, STRING, strlen (STRING))
632 
633 #define TARGET_ASM_NAMED_SECTION default_elf_asm_named_section
634 
635 /* Node: Data Output */
636 
637 #define ASM_OUTPUT_ASCII(STREAM, PTR, LEN) \
638  mmix_asm_output_ascii (STREAM, PTR, LEN)
639 
640 /* Node: Uninitialized Data */
641 
642 #define ASM_OUTPUT_ALIGNED_COMMON(ST, N, S, A) \
643  mmix_asm_output_aligned_common (ST, N, S, A)
644 
645 #define ASM_OUTPUT_ALIGNED_LOCAL(ST, N, S, A) \
646  mmix_asm_output_aligned_local (ST, N, S, A)
647 
648 
649 /* Node: Label Output */
650 
651 #define ASM_OUTPUT_LABEL(STREAM, NAME) \
652  mmix_asm_output_label (STREAM, NAME)
653 
654 #define ASM_OUTPUT_INTERNAL_LABEL(STREAM, NAME) \
655  mmix_asm_output_internal_label (STREAM, NAME)
656 
657 #define ASM_DECLARE_REGISTER_GLOBAL(STREAM, DECL, REGNO, NAME) \
658  mmix_asm_declare_register_global (STREAM, DECL, REGNO, NAME)
659 
660 #define GLOBAL_ASM_OP "\t.global "
661 
662 #define ASM_WEAKEN_LABEL(STREAM, NAME) \
663  mmix_asm_weaken_label (STREAM, NAME)
664 
665 #define MAKE_DECL_ONE_ONLY(DECL) \
666  mmix_make_decl_one_only (DECL)
667 
668 #define ASM_OUTPUT_LABELREF(STREAM, NAME) \
669  mmix_asm_output_labelref (STREAM, NAME)
670 
671 /* We insert a ":" to disambiguate against user symbols like L5.  */
672 #define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM) \
673  sprintf (LABEL, "*%s:%ld", PREFIX, (long)(NUM))
674 
675 /* Insert "::"; these are rarer than internal labels.  FIXME: Make sure no
676    ":" is seen in the object file; we don't really want that mmixal
677    feature visible there.  We don't want the default, which uses a dot;
678    that'd be incompatible with mmixal.  */
679 #define ASM_PN_FORMAT "%s::%lu"
680 
681 #define ASM_OUTPUT_DEF(STREAM, NAME, VALUE) \
682  mmix_asm_output_def (STREAM, NAME, VALUE)
683 
684 /* Node: Macros for Initialization */
685 /* We're compiling to ELF and linking to MMO; fundamental ELF features
686    that GCC depend on are there.  */
687 
688 /* These must be constant strings, since they're used in crtstuff.c.  */
689 #define INIT_SECTION_ASM_OP "\t.section .init,\"ax\" ! mmixal-incompatible"
690 
691 #define FINI_SECTION_ASM_OP "\t.section .fini,\"ax\" ! mmixal-incompatible"
692 
693 #define OBJECT_FORMAT_ELF
694 
695 
696 /* Node: Instruction Output */
697 
698 /* The non-$ register names must be prefixed with ":", since they're
699    affected by PREFIX.  We provide the non-colon names as additional
700    names.  */
701 #define REGISTER_NAMES							\
702  {"$0", "$1", "$2", "$3", "$4", "$5", "$6", "$7",			\
703   "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15",			\
704   "$16", "$17", "$18", "$19", "$20", "$21", "$22", "$23",		\
705   "$24", "$25", "$26", "$27", "$28", "$29", "$30", "$31",		\
706   "$32", "$33", "$34", "$35", "$36", "$37", "$38", "$39",		\
707   "$40", "$41", "$42", "$43", "$44", "$45", "$46", "$47",		\
708   "$48", "$49", "$50", "$51", "$52", "$53", "$54", "$55",		\
709   "$56", "$57", "$58", "$59", "$60", "$61", "$62", "$63",		\
710   "$64", "$65", "$66", "$67", "$68", "$69", "$70", "$71",		\
711   "$72", "$73", "$74", "$75", "$76", "$77", "$78", "$79",		\
712   "$80", "$81", "$82", "$83", "$84", "$85", "$86", "$87",		\
713   "$88", "$89", "$90", "$91", "$92", "$93", "$94", "$95",		\
714   "$96", "$97", "$98", "$99", "$100", "$101", "$102", "$103",		\
715   "$104", "$105", "$106", "$107", "$108", "$109", "$110", "$111",	\
716   "$112", "$113", "$114", "$115", "$116", "$117", "$118", "$119",	\
717   "$120", "$121", "$122", "$123", "$124", "$125", "$126", "$127",	\
718   "$128", "$129", "$130", "$131", "$132", "$133", "$134", "$135",	\
719   "$136", "$137", "$138", "$139", "$140", "$141", "$142", "$143",	\
720   "$144", "$145", "$146", "$147", "$148", "$149", "$150", "$151",	\
721   "$152", "$153", "$154", "$155", "$156", "$157", "$158", "$159",	\
722   "$160", "$161", "$162", "$163", "$164", "$165", "$166", "$167",	\
723   "$168", "$169", "$170", "$171", "$172", "$173", "$174", "$175",	\
724   "$176", "$177", "$178", "$179", "$180", "$181", "$182", "$183",	\
725   "$184", "$185", "$186", "$187", "$188", "$189", "$190", "$191",	\
726   "$192", "$193", "$194", "$195", "$196", "$197", "$198", "$199",	\
727   "$200", "$201", "$202", "$203", "$204", "$205", "$206", "$207",	\
728   "$208", "$209", "$210", "$211", "$212", "$213", "$214", "$215",	\
729   "$216", "$217", "$218", "$219", "$220", "$221", "$222", "$223",	\
730   "$224", "$225", "$226", "$227", "$228", "$229", "$230", "$231",	\
731   "$232", "$233", "$234", "$235", "$236", "$237", "$238", "$239",	\
732   "$240", "$241", "$242", "$243", "$244", "$245", "$246", "$247",	\
733   "$248", "$249", "$250", "$251", "$252", "$253", "$254", "$255",	\
734   ":rD",  ":rE",  ":rH",  ":rJ",  ":rR",  "ap_!BAD!", ":rO"}
735 
736 #define ADDITIONAL_REGISTER_NAMES			\
737  {{"sp", 254}, {":sp", 254}, {"rD", 256}, {"rE", 257},	\
738   {"rH", 258}, {"rJ", MMIX_rJ_REGNUM}, {"rO", MMIX_rO_REGNUM}}
739 
740 #define ASM_OUTPUT_REG_PUSH(STREAM, REGNO) \
741  mmix_asm_output_reg_push (STREAM, REGNO)
742 
743 #define ASM_OUTPUT_REG_POP(STREAM, REGNO) \
744  mmix_asm_output_reg_pop (STREAM, REGNO)
745 
746 
747 /* Node: Dispatch Tables */
748 
749 /* We define both types, since SImode is the better, but DImode the only
750    possible for mmixal so that's the one actually used.  */
751 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL) \
752  mmix_asm_output_addr_diff_elt (STREAM, BODY, VALUE, REL)
753 
754 #define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE) \
755  mmix_asm_output_addr_vec_elt (STREAM, VALUE)
756 
757 
758 /* Node: Exception Region Output */
759 /* (empty) */
760 
761 /* Node: Alignment Output */
762 
763 #define ASM_OUTPUT_SKIP(STREAM, NBYTES) \
764  mmix_asm_output_skip (STREAM, NBYTES)
765 
766 #define ASM_OUTPUT_ALIGN(STREAM, POWER) \
767  mmix_asm_output_align (STREAM, POWER)
768 
769 
770 /* Node: All Debuggers */
771 
772 #define DBX_REGISTER_NUMBER(REGNO) \
773  mmix_dbx_register_number (REGNO)
774 
775 
776 /* Node: DBX Options */
777 /* (empty) */
778 /* Node: DBX Hooks */
779 /* (empty) */
780 /* Node: File Names and DBX */
781 /* (empty) */
782 
783 
784 /* Node: SDB and DWARF */
785 #define DWARF2_DEBUGGING_INFO 1
786 #define DWARF2_ASM_LINE_DEBUG_INFO 1
787 
788 /* Node: Misc */
789 
790 /* There's no way to get a PC-relative offset into tables for SImode, so
791    for the moment we have absolute entries in DImode.
792    When we're going ELF, these should be SImode and 1.  */
793 #define CASE_VECTOR_MODE DImode
794 #define CASE_VECTOR_PC_RELATIVE 0
795 
796 #define WORD_REGISTER_OPERATIONS 1
797 
798 /* We have a choice, which makes this yet another parameter to tweak.  The
799    gut feeling is currently that SIGN_EXTEND wins; "int" is more frequent
800    than "unsigned int", and we have signed characters.  FIXME: measure.  */
801 #define LOAD_EXTEND_OP(MODE) (TARGET_ZERO_EXTEND ? ZERO_EXTEND : SIGN_EXTEND)
802 
803 #define MOVE_MAX 8
804 
805 #define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC) 1
806 
807 /* ??? MMIX allows a choice of STORE_FLAG_VALUE.  Revisit later,
808    we don't have scc expanders yet.  */
809 
810 #define Pmode DImode
811 
812 #define FUNCTION_MODE QImode
813 
814 #define NO_IMPLICIT_EXTERN_C
815 
816 /* mmix-knuth-mmixware target has no support of C99 runtime */
817 #undef TARGET_LIBC_HAS_FUNCTION
818 #define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
819 
820 /* These are checked.  */
821 #define DOLLARS_IN_IDENTIFIERS 0
822 #define NO_DOLLAR_IN_LABEL
823 #define NO_DOT_IN_LABEL
824 
825 #endif /* GCC_MMIX_H */
826 /*
827  * Local variables:
828  * eval: (c-set-style "gnu")
829  * indent-tabs-mode: t
830  * End:
831  */
832