1 /* Definitions of target machine for GNU compiler, for MMIX.
2 Copyright (C) 2000-2023 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 LOCAL_ALIGNMENT(TYPE, BASIC_ALIGN) \
171 mmix_local_alignment (TYPE, BASIC_ALIGN)
172
173 /* Following other ports, this seems to most commonly be the word-size,
174 so let's do that here too. */
175 #define EMPTY_FIELD_BOUNDARY 64
176
177 /* We chose to have this low solely for similarity with the alpha. It has
178 nothing to do with passing the tests dg/c99-scope-2 and
179 execute/align-1.c. Nothing. Though the tests seem wrong. Padding of
180 the structure is automatically added to get alignment when needed if we
181 set this to just byte-boundary. */
182 #define STRUCTURE_SIZE_BOUNDARY 8
183
184 /* The lower bits are ignored. */
185 #define STRICT_ALIGNMENT 1
186
187
188 /* Node: Type Layout */
189
190 /* It might seem more natural to have 64-bit ints on a 64-bit machine,
191 but then an occasional MMIX programmer needs to know how to put a lot
192 of __attribute__ stuff to get to the 8, 16 and 32-bit modes rather
193 than the "intuitive" char, short and int types. */
194 #define INT_TYPE_SIZE 32
195 #define SHORT_TYPE_SIZE 16
196 #define LONG_LONG_TYPE_SIZE 64
197
198 #define FLOAT_TYPE_SIZE 32
199 #define DOUBLE_TYPE_SIZE 64
200 #define LONG_DOUBLE_TYPE_SIZE 64
201
202 #define DEFAULT_SIGNED_CHAR 1
203
204
205 /* Node: Register Basics */
206 /* We tell GCC about all 256 general registers, and we also include
207 rD, rE, rH, rJ, rR and rO (in that order) so we can describe what insns
208 clobber them. We use a faked register for the argument pointer. It is
209 always eliminated towards the frame-pointer or the stack-pointer, never
210 output in assembly. Any fixed register would do for this, like $255,
211 but future debugging is easier when using a separate register. It
212 counts as a global register for pseudorandom reasons. */
213 #define FIRST_PSEUDO_REGISTER 263
214
215 /* We treat general registers with no assigned purpose as fixed. The
216 stack pointer, $254, is also fixed. Register $255 is referred to as a
217 temporary register in the MMIX papers, and used as such in mmixal, so
218 it should not be used as a stack pointer. We set it to fixed, and use
219 it "manually" at times of despair. */
220 #define FIXED_REGISTERS \
221 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
222 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
223 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
224 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
225 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
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, 0, 0, 0, 0, 0, 0, 0, 1, 1, \
237 1, 1, 0, 0, 0, 1, 1 \
238 }
239
240 /* General registers are fixed and therefore "historically" marked
241 call-used. (FIXME: This has changed). Registers $15..$31 are
242 call-clobbered; we'll put arguments in $16 and up, and we need $15 for
243 the MMIX register-stack "hole". */
244 #define CALL_USED_REGISTERS \
245 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, \
246 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
247 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
248 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 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, 0, 1, 1, \
261 1, 1, 1, 1, 1, 1, 1 \
262 }
263
264 #define INCOMING_REGNO(OUT) mmix_opposite_regno (OUT, 0)
265
266 #define OUTGOING_REGNO(IN) mmix_opposite_regno (IN, 1)
267
268 /* Defining LOCAL_REGNO is necessary in presence of prologue/epilogue,
269 else GCC will be confused that those registers aren't saved and
270 restored. */
271 #define LOCAL_REGNO(REGNO) mmix_local_regno (REGNO)
272
273 /* Node: Allocation Order */
274
275 /* We should allocate registers from 0 to 31 by increasing number, because
276 I think that's what people expect. Beyond that, just use
277 call-clobbered global registers first, then call-clobbered special
278 registers. Last, the fixed registers. */
279 #define MMIX_MMIXWARE_ABI_REG_ALLOC_ORDER \
280 { 0, 1, 2, 3, 4, 5, 6, 7, \
281 8, 9, 10, 11, 12, 13, 14, 15, \
282 16, 17, 18, 19, 20, 21, 22, 23, \
283 24, 25, 26, 27, 28, 29, 30, 31, \
284 \
285 252, 251, 250, 249, 248, 247, \
286 \
287 253, \
288 \
289 258, 260, 259, \
290 \
291 32, 33, 34, 35, 36, 37, 38, 39, \
292 40, 41, 42, 43, 44, 45, 46, 47, \
293 48, 49, 50, 51, 52, 53, 54, 55, \
294 56, 57, 58, 59, 60, 61, 62, 63, \
295 64, 65, 66, 67, 68, 69, 70, 71, \
296 72, 73, 74, 75, 76, 77, 78, 79, \
297 80, 81, 82, 83, 84, 85, 86, 87, \
298 88, 89, 90, 91, 92, 93, 94, 95, \
299 96, 97, 98, 99, 100, 101, 102, 103, \
300 104, 105, 106, 107, 108, 109, 110, 111, \
301 112, 113, 114, 115, 116, 117, 118, 119, \
302 120, 121, 122, 123, 124, 125, 126, 127, \
303 128, 129, 130, 131, 132, 133, 134, 135, \
304 136, 137, 138, 139, 140, 141, 142, 143, \
305 144, 145, 146, 147, 148, 149, 150, 151, \
306 152, 153, 154, 155, 156, 157, 158, 159, \
307 160, 161, 162, 163, 164, 165, 166, 167, \
308 168, 169, 170, 171, 172, 173, 174, 175, \
309 176, 177, 178, 179, 180, 181, 182, 183, \
310 184, 185, 186, 187, 188, 189, 190, 191, \
311 192, 193, 194, 195, 196, 197, 198, 199, \
312 200, 201, 202, 203, 204, 205, 206, 207, \
313 208, 209, 210, 211, 212, 213, 214, 215, \
314 216, 217, 218, 219, 220, 221, 222, 223, \
315 224, 225, 226, 227, 228, 229, 230, 231, \
316 232, 233, 234, 235, 236, 237, 238, 239, \
317 240, 241, 242, 243, 244, 245, 246, \
318 \
319 254, 255, 256, 257, 261, 262 \
320 }
321
322 /* As a convenience, we put this nearby, for ease of comparison.
323 First, call-clobbered registers in reverse order of assignment as
324 parameters (also the top ones; not because they're parameters, but
325 for continuity).
326
327 Second, saved registers that go on the register-stack.
328
329 Third, special registers rH, rR and rJ. They should not normally be
330 allocated, but since they're call-clobbered, it is cheaper to use one
331 of them than using a call-saved register for a call-clobbered use,
332 assuming it is referenced a very limited number of times. Other global
333 and fixed registers come next; they are never allocated. */
334 #define MMIX_GNU_ABI_REG_ALLOC_ORDER \
335 { 252, 251, 250, 249, 248, 247, 246, \
336 245, 244, 243, 242, 241, 240, 239, 238, \
337 237, 236, 235, 234, 233, 232, 231, \
338 \
339 0, 1, 2, 3, 4, 5, 6, 7, \
340 8, 9, 10, 11, 12, 13, 14, 15, \
341 16, 17, 18, 19, 20, 21, 22, 23, \
342 24, 25, 26, 27, 28, 29, 30, 31, \
343 \
344 253, \
345 \
346 258, 260, 259, \
347 \
348 32, 33, 34, 35, 36, 37, 38, 39, \
349 40, 41, 42, 43, 44, 45, 46, 47, \
350 48, 49, 50, 51, 52, 53, 54, 55, \
351 56, 57, 58, 59, 60, 61, 62, 63, \
352 64, 65, 66, 67, 68, 69, 70, 71, \
353 72, 73, 74, 75, 76, 77, 78, 79, \
354 80, 81, 82, 83, 84, 85, 86, 87, \
355 88, 89, 90, 91, 92, 93, 94, 95, \
356 96, 97, 98, 99, 100, 101, 102, 103, \
357 104, 105, 106, 107, 108, 109, 110, 111, \
358 112, 113, 114, 115, 116, 117, 118, 119, \
359 120, 121, 122, 123, 124, 125, 126, 127, \
360 128, 129, 130, 131, 132, 133, 134, 135, \
361 136, 137, 138, 139, 140, 141, 142, 143, \
362 144, 145, 146, 147, 148, 149, 150, 151, \
363 152, 153, 154, 155, 156, 157, 158, 159, \
364 160, 161, 162, 163, 164, 165, 166, 167, \
365 168, 169, 170, 171, 172, 173, 174, 175, \
366 176, 177, 178, 179, 180, 181, 182, 183, \
367 184, 185, 186, 187, 188, 189, 190, 191, \
368 192, 193, 194, 195, 196, 197, 198, 199, \
369 200, 201, 202, 203, 204, 205, 206, 207, \
370 208, 209, 210, 211, 212, 213, 214, 215, \
371 216, 217, 218, 219, 220, 221, 222, 223, \
372 224, 225, 226, 227, 228, 229, 230, \
373 \
374 254, 255, 256, 257, 261, 262 \
375 }
376
377 /* The default one. */
378 #define REG_ALLOC_ORDER MMIX_MMIXWARE_ABI_REG_ALLOC_ORDER
379
380 /* Node: Leaf Functions */
381 /* (empty) */
382
383
384 /* Node: Register Classes */
385
386 enum reg_class
387 {
388 NO_REGS, GENERAL_REGS, REMAINDER_REG, HIMULT_REG,
389 SYSTEM_REGS, ALL_REGS, LIM_REG_CLASSES
390 };
391
392 #define N_REG_CLASSES (int) LIM_REG_CLASSES
393
394 #define REG_CLASS_NAMES \
395 {"NO_REGS", "GENERAL_REGS", "REMAINDER_REG", "HIMULT_REG", \
396 "SYSTEM_REGS", "ALL_REGS"}
397
398 /* Note that the contents of each item is always 32 bits. */
399 #define REG_CLASS_CONTENTS \
400 {{0, 0, 0, 0, 0, 0, 0, 0, 0}, \
401 {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x20}, \
402 {0, 0, 0, 0, 0, 0, 0, 0, 0x10}, \
403 {0, 0, 0, 0, 0, 0, 0, 0, 4}, \
404 {0, 0, 0, 0, 0, 0, 0, 0, 0x7f}, \
405 {~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0x7f}}
406
407 #define REGNO_REG_CLASS(REGNO) \
408 ((REGNO) <= MMIX_LAST_GENERAL_REGISTER \
409 || (REGNO) == MMIX_ARG_POINTER_REGNUM \
410 ? GENERAL_REGS \
411 : (REGNO) == MMIX_REMAINDER_REGNUM ? REMAINDER_REG \
412 : (REGNO) == MMIX_HIMULT_REGNUM ? HIMULT_REG : SYSTEM_REGS)
413
414 #define BASE_REG_CLASS GENERAL_REGS
415
416 #define INDEX_REG_CLASS GENERAL_REGS
417
418 #define REGNO_OK_FOR_BASE_P(REGNO) \
419 ((REGNO) <= MMIX_LAST_GENERAL_REGISTER \
420 || (REGNO) == MMIX_ARG_POINTER_REGNUM \
421 || (reg_renumber[REGNO] > 0 \
422 && reg_renumber[REGNO] <= MMIX_LAST_GENERAL_REGISTER))
423
424 #define REGNO_OK_FOR_INDEX_P(REGNO) REGNO_OK_FOR_BASE_P (REGNO)
425
426 #define SECONDARY_INPUT_RELOAD_CLASS(CLASS, MODE, X) \
427 mmix_secondary_reload_class (CLASS, MODE, X, 1)
428
429 #define SECONDARY_OUTPUT_RELOAD_CLASS(CLASS, MODE, X) \
430 mmix_secondary_reload_class (CLASS, MODE, X, 0)
431
432 #define CLASS_MAX_NREGS(CLASS, MODE) targetm.hard_regno_nregs (CLASS, MODE)
433
434
435 /* Node: Frame Layout */
436
437 #define STACK_GROWS_DOWNWARD 1
438 #define FRAME_GROWS_DOWNWARD 1
439
440 #define FIRST_PARM_OFFSET(FUNDECL) 0
441
442 #define DYNAMIC_CHAIN_ADDRESS(FRAMEADDR) \
443 mmix_dynamic_chain_address (FRAMEADDR)
444
445 /* FIXME: It seems RETURN_ADDR_OFFSET is undocumented. */
446
447 #define SETUP_FRAME_ADDRESSES() \
448 mmix_setup_frame_addresses ()
449
450 #define RETURN_ADDR_RTX(COUNT, FRAME) \
451 mmix_return_addr_rtx (COUNT, FRAME)
452
453 /* It's in rJ before we store it somewhere. */
454 #define INCOMING_RETURN_ADDR_RTX \
455 gen_rtx_REG (Pmode, MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
456
457 /* FIXME: This does not seem properly documented or cross-indexed.
458 Nowhere except in the code does it say it *has* to be in the range
459 0..255, or else it will be truncated. That goes for the default too. */
460 #define DWARF_FRAME_RETURN_COLUMN \
461 DWARF_FRAME_REGNUM (MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
462
463 /* No return address is stored there. */
464 #define INCOMING_FRAME_SP_OFFSET 0
465
466 /* Node: Stack Checking */
467 /* (empty) */
468
469
470 /* Node: Exception Handling */
471
472 #define EH_RETURN_DATA_REGNO(N) \
473 mmix_eh_return_data_regno (N)
474
475 #define EH_RETURN_STACKADJ_RTX \
476 mmix_eh_return_stackadj_rtx ()
477
478 #define EH_RETURN_HANDLER_RTX \
479 mmix_eh_return_handler_rtx ()
480
481 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
482 mmix_asm_preferred_eh_data_format (CODE, GLOBAL)
483
484 /* Node: Frame Registers */
485 #define STACK_POINTER_REGNUM MMIX_STACK_POINTER_REGNUM
486
487 /* Perhaps we can use HARD_FRAME_POINTER_REGNUM and decide later on
488 what register we want to use. */
489 #define FRAME_POINTER_REGNUM MMIX_FRAME_POINTER_REGNUM
490 #define ARG_POINTER_REGNUM MMIX_ARG_POINTER_REGNUM
491
492 #define STATIC_CHAIN_REGNUM MMIX_STATIC_CHAIN_REGNUM
493
494
495 /* Node: Elimination */
496
497 /* The frame-pointer is stored in a location that either counts to the
498 offset of incoming parameters, or that counts to the offset of the
499 frame, so we can't use a single offset. We therefore eliminate those
500 two separately. */
501 #define ELIMINABLE_REGS \
502 {{ARG_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
503 {ARG_POINTER_REGNUM, FRAME_POINTER_REGNUM}, \
504 {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}}
505
506 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
507 (OFFSET) = mmix_initial_elimination_offset (FROM, TO)
508
509
510 /* Node: Stack Arguments */
511
512 #define ACCUMULATE_OUTGOING_ARGS 1
513
514
515 /* Node: Register Arguments */
516
517 typedef struct { int regs; int lib; } CUMULATIVE_ARGS;
518
519 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
520 ((CUM).regs = 0, (CUM).lib = ((LIBNAME) != 0))
521
522 #define FUNCTION_ARG_REGNO_P(REGNO) \
523 mmix_function_arg_regno_p (REGNO, 0)
524
525
526 /* Node: Caller Saves */
527 /* (empty) */
528
529
530 /* Node: Function Entry */
531
532 /* See mmix.cc for TARGET_ASM_FUNCTION_PROLOGUE and
533 TARGET_ASM_FUNCTION_EPILOGUE. */
534
535 /* We need to say that the epilogue uses the return address, so the
536 initial-value machinery restores it. FIXME: Some targets
537 conditionalize on "reload_completed &&". Investigate difference.
538 FIXME: Not needed if nonlocal_goto_stack_level. */
539 #define EPILOGUE_USES(REGNO) \
540 ((REGNO) == MMIX_INCOMING_RETURN_ADDRESS_REGNUM)
541
542 /* Node: Profiling */
543 #define FUNCTION_PROFILER(FILE, LABELNO) \
544 mmix_function_profiler (FILE, LABELNO)
545
546 /* Node: Trampolines */
547
548 #define TRAMPOLINE_SIZE (4*UNITS_PER_WORD)
549 #define TRAMPOLINE_ALIGNMENT BITS_PER_WORD
550
551 /* Node: Addressing Modes */
552
553 #define CONSTANT_ADDRESS_P(X) \
554 mmix_constant_address_p (X)
555
556 #define MAX_REGS_PER_ADDRESS 2
557
558
559 /* Node: Condition Code */
560
561 #define SELECT_CC_MODE(OP, X, Y) \
562 mmix_select_cc_mode (OP, X, Y)
563
564 /* A definition of CANONICALIZE_COMPARISON that changed LE and GT
565 comparisons with -1 to LT and GE respectively, and LT, LTU, GE or GEU
566 comparisons with 256 to 255 and LE, LEU, GT and GTU has been
567 ineffective; the code path for performing the changes did not trig for
568 neither the GCC testsuite nor ghostscript-6.52 nor Knuth's mmix.tar.gz
569 itself (core GCC functionality supposedly handling it) with sources
570 from 2002-06-06. */
571
572 #define REVERSIBLE_CC_MODE(MODE) \
573 mmix_reversible_cc_mode (MODE)
574
575
576 /* Node: Costs */
577
578 #define SLOW_BYTE_ACCESS 0
579
580 /* A PUSHJ doesn't cost more than a PUSHGO, so don't needlessly create
581 the latter. */
582 #define NO_FUNCTION_CSE 1
583
584 /* Node: Sections */
585
586 /* This must be a constant string, since it's used in crtstuff.c. */
587 #define TEXT_SECTION_ASM_OP \
588 "\t.text ! mmixal:= 9H LOC 8B"
589
590 /* FIXME: Not documented. */
591 #define DATA_SECTION_ASM_OP \
592 mmix_data_section_asm_op ()
593
594 #define READONLY_DATA_SECTION_ASM_OP "\t.section\t.rodata"
595
596 /* Node: PIC */
597 /* (empty) */
598
599
600 /* Node: File Framework */
601
602 /* While any other punctuation character but ";" would do, we prefer "%"
603 or "!"; "!" is an unary operator and so will not be mistakenly included
604 in correctly formed expressions. The hash character adds mass; catches
605 the eye. We can't have it as a comment char by itself, since it's a
606 hex-number prefix. */
607 #define ASM_COMMENT_START "!#"
608
609 /* These aren't currently functional. We just keep them as markers. */
610 #define ASM_APP_ON "%APP\n"
611 #define ASM_APP_OFF "%NO_APP\n"
612
613 #define OUTPUT_QUOTED_STRING(STREAM, STRING) \
614 mmix_output_quoted_string (STREAM, STRING, strlen (STRING))
615
616 #define TARGET_ASM_NAMED_SECTION default_elf_asm_named_section
617
618 /* Node: Data Output */
619
620 #define ASM_OUTPUT_ASCII(STREAM, PTR, LEN) \
621 mmix_asm_output_ascii (STREAM, PTR, LEN)
622
623 /* Make output more ELF-like, by emitting .hidden for hidden symbols
624 (which don't really matter for mmix-knuth-mmixware). */
625 #define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME) \
626 default_elf_asm_output_external (FILE, DECL, NAME)
627
628 /* Node: Uninitialized Data */
629
630 #define ASM_OUTPUT_ALIGNED_COMMON(ST, N, S, A) \
631 mmix_asm_output_aligned_common (ST, N, S, A)
632
633 #define ASM_OUTPUT_ALIGNED_LOCAL(ST, N, S, A) \
634 mmix_asm_output_aligned_local (ST, N, S, A)
635
636
637 /* Node: Label Output */
638
639 #define ASM_OUTPUT_LABEL(STREAM, NAME) \
640 mmix_asm_output_label (STREAM, NAME)
641
642 #define ASM_OUTPUT_INTERNAL_LABEL(STREAM, NAME) \
643 mmix_asm_output_internal_label (STREAM, NAME)
644
645 #define ASM_DECLARE_REGISTER_GLOBAL(STREAM, DECL, REGNO, NAME) \
646 mmix_asm_declare_register_global (STREAM, DECL, REGNO, NAME)
647
648 #define GLOBAL_ASM_OP "\t.global "
649
650 #define ASM_WEAKEN_LABEL(STREAM, NAME) \
651 mmix_asm_weaken_label (STREAM, NAME)
652
653 #define MAKE_DECL_ONE_ONLY(DECL) \
654 mmix_make_decl_one_only (DECL)
655
656 #define ASM_OUTPUT_LABELREF(STREAM, NAME) \
657 mmix_asm_output_labelref (STREAM, NAME)
658
659 /* We insert a ":" to disambiguate against user symbols like L5. */
660 #define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM) \
661 sprintf (LABEL, "*%s:%ld", PREFIX, (long)(NUM))
662
663 /* Insert "::"; these are rarer than internal labels. FIXME: Make sure no
664 ":" is seen in the object file; we don't really want that mmixal
665 feature visible there. We don't want the default, which uses a dot;
666 that'd be incompatible with mmixal. */
667 #define ASM_PN_FORMAT "%s::%lu"
668
669 #define ASM_OUTPUT_DEF(STREAM, NAME, VALUE) \
670 mmix_asm_output_def (STREAM, NAME, VALUE)
671
672 /* Node: Macros for Initialization */
673 /* We're compiling to ELF and linking to MMO; fundamental ELF features
674 that GCC depend on are there. */
675
676 /* These must be constant strings, since they're used in crtstuff.c. */
677 #define INIT_SECTION_ASM_OP "\t.section .init,\"ax\" ! mmixal-incompatible"
678
679 #define FINI_SECTION_ASM_OP "\t.section .fini,\"ax\" ! mmixal-incompatible"
680
681 #define OBJECT_FORMAT_ELF
682
683
684 /* Node: Instruction Output */
685
686 /* The non-$ register names must be prefixed with ":", since they're
687 affected by PREFIX. We provide the non-colon names as additional
688 names. */
689 #define REGISTER_NAMES \
690 {"$0", "$1", "$2", "$3", "$4", "$5", "$6", "$7", \
691 "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", \
692 "$16", "$17", "$18", "$19", "$20", "$21", "$22", "$23", \
693 "$24", "$25", "$26", "$27", "$28", "$29", "$30", "$31", \
694 "$32", "$33", "$34", "$35", "$36", "$37", "$38", "$39", \
695 "$40", "$41", "$42", "$43", "$44", "$45", "$46", "$47", \
696 "$48", "$49", "$50", "$51", "$52", "$53", "$54", "$55", \
697 "$56", "$57", "$58", "$59", "$60", "$61", "$62", "$63", \
698 "$64", "$65", "$66", "$67", "$68", "$69", "$70", "$71", \
699 "$72", "$73", "$74", "$75", "$76", "$77", "$78", "$79", \
700 "$80", "$81", "$82", "$83", "$84", "$85", "$86", "$87", \
701 "$88", "$89", "$90", "$91", "$92", "$93", "$94", "$95", \
702 "$96", "$97", "$98", "$99", "$100", "$101", "$102", "$103", \
703 "$104", "$105", "$106", "$107", "$108", "$109", "$110", "$111", \
704 "$112", "$113", "$114", "$115", "$116", "$117", "$118", "$119", \
705 "$120", "$121", "$122", "$123", "$124", "$125", "$126", "$127", \
706 "$128", "$129", "$130", "$131", "$132", "$133", "$134", "$135", \
707 "$136", "$137", "$138", "$139", "$140", "$141", "$142", "$143", \
708 "$144", "$145", "$146", "$147", "$148", "$149", "$150", "$151", \
709 "$152", "$153", "$154", "$155", "$156", "$157", "$158", "$159", \
710 "$160", "$161", "$162", "$163", "$164", "$165", "$166", "$167", \
711 "$168", "$169", "$170", "$171", "$172", "$173", "$174", "$175", \
712 "$176", "$177", "$178", "$179", "$180", "$181", "$182", "$183", \
713 "$184", "$185", "$186", "$187", "$188", "$189", "$190", "$191", \
714 "$192", "$193", "$194", "$195", "$196", "$197", "$198", "$199", \
715 "$200", "$201", "$202", "$203", "$204", "$205", "$206", "$207", \
716 "$208", "$209", "$210", "$211", "$212", "$213", "$214", "$215", \
717 "$216", "$217", "$218", "$219", "$220", "$221", "$222", "$223", \
718 "$224", "$225", "$226", "$227", "$228", "$229", "$230", "$231", \
719 "$232", "$233", "$234", "$235", "$236", "$237", "$238", "$239", \
720 "$240", "$241", "$242", "$243", "$244", "$245", "$246", "$247", \
721 "$248", "$249", "$250", "$251", "$252", "$253", "$254", "$255", \
722 ":rD", ":rE", ":rH", ":rJ", ":rR", "ap_!BAD!", ":rO"}
723
724 #define ADDITIONAL_REGISTER_NAMES \
725 {{"sp", 254}, {":sp", 254}, {"rD", 256}, {"rE", 257}, \
726 {"rH", 258}, {"rJ", MMIX_rJ_REGNUM}, {"rO", MMIX_rO_REGNUM}}
727
728 #define ASM_OUTPUT_REG_PUSH(STREAM, REGNO) \
729 mmix_asm_output_reg_push (STREAM, REGNO)
730
731 #define ASM_OUTPUT_REG_POP(STREAM, REGNO) \
732 mmix_asm_output_reg_pop (STREAM, REGNO)
733
734
735 /* Node: Dispatch Tables */
736
737 /* We define both types, since SImode is the better, but DImode the only
738 possible for mmixal so that's the one actually used. */
739 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL) \
740 mmix_asm_output_addr_diff_elt (STREAM, BODY, VALUE, REL)
741
742 #define ASM_OUTPUT_ADDR_VEC_ELT(STREAM, VALUE) \
743 mmix_asm_output_addr_vec_elt (STREAM, VALUE)
744
745
746 /* Node: Exception Region Output */
747 /* (empty) */
748
749 /* Node: Alignment Output */
750
751 #define ASM_OUTPUT_SKIP(STREAM, NBYTES) \
752 mmix_asm_output_skip (STREAM, NBYTES)
753
754 #define ASM_OUTPUT_ALIGN(STREAM, POWER) \
755 mmix_asm_output_align (STREAM, POWER)
756
757
758 /* Node: All Debuggers */
759
760 #define DEBUGGER_REGNO(REGNO) \
761 mmix_debugger_regno (REGNO)
762
763 /* Node: DWARF */
764 #define DWARF2_DEBUGGING_INFO 1
765 #define DWARF2_ASM_LINE_DEBUG_INFO 1
766
767 /* Node: Misc */
768
769 /* There's no way to get a PC-relative offset into tables for SImode, so
770 for the moment we have absolute entries in DImode.
771 When we're going ELF, these should be SImode and 1. */
772 #define CASE_VECTOR_MODE DImode
773 #define CASE_VECTOR_PC_RELATIVE 0
774
775 #define WORD_REGISTER_OPERATIONS 1
776
777 /* We have a choice, which makes this yet another parameter to tweak. The
778 gut feeling is currently that SIGN_EXTEND wins; "int" is more frequent
779 than "unsigned int", and we have signed characters. FIXME: measure. */
780 #define LOAD_EXTEND_OP(MODE) (TARGET_ZERO_EXTEND ? ZERO_EXTEND : SIGN_EXTEND)
781
782 #define MOVE_MAX 8
783
784 /* ??? MMIX allows a choice of STORE_FLAG_VALUE. Revisit later,
785 we don't have scc expanders yet. */
786
787 #define Pmode DImode
788
789 #define FUNCTION_MODE QImode
790
791 /* mmix-knuth-mmixware target has no support of C99 runtime */
792 #undef TARGET_LIBC_HAS_FUNCTION
793 #define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
794
795 /* These are checked. */
796 #define DOLLARS_IN_IDENTIFIERS 0
797 #define NO_DOLLAR_IN_LABEL
798 #define NO_DOT_IN_LABEL
799
800 #endif /* GCC_MMIX_H */
801 /*
802 * Local variables:
803 * eval: (c-set-style "gnu")
804 * indent-tabs-mode: t
805 * End:
806 */