1 /* Definitions for GCC.  Part of the machine description for CRIS.
2    Copyright (C) 1998-2022 Free Software Foundation, Inc.
3    Contributed by Axis Communications.  Written by Hans-Peter Nilsson.
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 /* After the first "Node:" comment comes all preprocessor directives and
22    attached declarations described in the info files, the "Using and
23    Porting GCC" manual (uapgcc), in the same order as found in the "Target
24    macros" section in the gcc-2.9x CVS edition of 2000-03-17.  FIXME: Not
25    really, but needs an update anyway.
26 
27    There is no generic copy-of-uapgcc comment, you'll have to see uapgcc
28    for that.  If applicable, there is a CRIS-specific comment.  The order
29    of macro definitions follow the order in the manual.  Every section in
30    the manual (node in the info pages) has an introductory `Node:
31    <subchapter>' comment.  If no macros are defined for a section, only
32    the section-comment is present.  */
33 
34 /* Note that other header files (e.g. config/elfos.h, config/linux.h,
35    and config/cris/linux.h) are responsible for lots of settings not
36    repeated below.  This file contains general CRIS definitions
37    and definitions for the cris-*-elf subtarget.  */
38 
39 /* We don't want to use gcc_assert for everything, as that can be
40    compiled out.  */
41 #define CRIS_ASSERT(x) \
42  do { if (!(x)) internal_error ("CRIS-port assertion failed: %s", #x); } while (0)
43 
44 /* Replacement for REG_P since it does not match SUBREGs.  Happens for
45    testcase Axis-20000320 with gcc-2.9x.  */
46 #define REG_S_P(x) \
47  (REG_P (x) || (GET_CODE (x) == SUBREG && REG_P (XEXP (x, 0))))
48 
49 /* Last register in main register bank r0..r15.  */
50 #define CRIS_LAST_GENERAL_REGISTER 15
51 
52 /* Descriptions of registers used for arguments.  */
53 #define CRIS_FIRST_ARG_REG 10
54 #define CRIS_MAX_ARGS_IN_REGS 4
55 
56 /* See also *_REGNUM constants in cris.md.  */
57 
58 /* Most of the time, we need the index into the register-names array.
59    When passing debug-info, we need the real hardware register number.  */
60 #define CRIS_CANONICAL_SRP_REGNUM (16 + 11)
61 #define CRIS_CANONICAL_MOF_REGNUM (16 + 7)
62 /* We have CCR in all models including v10, but that's 16 bits, so let's
63    prefer the DCCR number, which is a DMA pointer in pre-v8, so we'll
64    never clash with it for GCC purposes.  */
65 #define CRIS_CANONICAL_CC0_REGNUM (16 + 13)
66 
67 #define CRIS_FUNCTION_ARG_SIZE(MODE, TYPE)        \
68   ((MODE) != BLKmode ? GET_MODE_SIZE (MODE)       \
69    : (unsigned) int_size_in_bytes (TYPE))
70 
71 /* Which CPU version this is.  The parsed and adjusted cris_cpu_str.  */
72 extern int cris_cpu_version;
73 
74 
75 /* Node: Driver */
76 
77 /* Also provide canonical vN definitions when user specifies an alias.  */
78 
79 #define CPP_SPEC \
80  "%{mtune=*:-D__tune_%* %{mtune=v*:-D__CRIS_arch_tune=%*}\
81    %{mtune=etrax4:-D__tune_v3 -D__CRIS_arch_tune=3}\
82    %{mtune=etrax100:-D__tune_v8 -D__CRIS_arch_tune=8}\
83    %{mtune=svinto:-D__tune_v8 -D__CRIS_arch_tune=8}\
84    %{mtune=etrax100lx:-D__tune_v10 -D__CRIS_arch_tune=10}\
85    %{mtune=ng:-D__tune_v10 -D__CRIS_arch_tune=10}}\
86   %{mcpu=*:-D__arch_%* %{mcpu=v*:-D__CRIS_arch_version=%*}\
87    %{mcpu=etrax4:-D__arch_v3 -D__CRIS_arch_version=3}\
88    %{mcpu=etrax100:-D__arch_v8 -D__CRIS_arch_version=8}\
89    %{mcpu=svinto:-D__arch_v8 -D__CRIS_arch_version=8}\
90    %{mcpu=etrax100lx:-D__arch_v10 -D__CRIS_arch_version=10}\
91    %{mcpu=ng:-D__arch_v10 -D__CRIS_arch_version=10}}\
92   %{march=*:-D__arch_%* %{march=v*:-D__CRIS_arch_version=%*}\
93    %{march=etrax4:-D__arch_v3 -D__CRIS_arch_version=3}\
94    %{march=etrax100:-D__arch_v8 -D__CRIS_arch_version=8}\
95    %{march=svinto:-D__arch_v8 -D__CRIS_arch_version=8}\
96    %{march=etrax100lx:-D__arch_v10 -D__CRIS_arch_version=10}\
97    %{march=ng:-D__arch_v10 -D__CRIS_arch_version=10}}\
98   %{metrax100:-D__arch__v8 -D__CRIS_arch_version=8}\
99   %{metrax4:-D__arch__v3 -D__CRIS_arch_version=3}\
100   %(cpp_subtarget)"
101 
102 /* For the cris-*-elf subtarget.  */
103 
104 #define CRIS_DEFAULT_TUNE "10"
105 #define CRIS_ARCH_CPP_DEFAULT
106 #define CRIS_DEFAULT_ASM_ARCH_OPTION ""
107 
108 #ifdef TARGET_CPU_DEFAULT
109 #if TARGET_CPU_DEFAULT != 10
110  #error "Due to '()'; e.g. '#define TARGET_CPU_DEFAULT (10)', stringize TARGET_CPU_DEFAULT isn't useful: update manually."
111 #endif
112 
113 #undef CRIS_ARCH_CPP_DEFAULT
114 #define CRIS_ARCH_CPP_DEFAULT \
115  "%{!march=*:\
116    %{!metrax*:\
117     %{!mcpu=*:\
118      %{!mtune=*:-D__tune_v" CRIS_DEFAULT_TUNE "}\
119      -D__arch_v" CRIS_DEFAULT_TUNE \
120    " -D__CRIS_arch_version=" CRIS_DEFAULT_TUNE "}}}"
121 #endif
122 
123 #define CRIS_CPP_SUBTARGET_SPEC \
124  "%{mbest-lib-options:\
125    %{!moverride-best-lib-options:\
126    %{!march=*:%{!metrax*:%{!mcpu=*:\
127       -D__tune_v" CRIS_DEFAULT_TUNE \
128     " -D__CRIS_arch_tune=" CRIS_DEFAULT_TUNE "}}}}}"\
129  CRIS_ARCH_CPP_DEFAULT
130 
131 /* Override previous definitions (../linux.h).  */
132 #undef CC1_SPEC
133 #define CC1_SPEC \
134  "%{metrax4:-march=v3}\
135   %{metrax100:-march=v8}\
136   %{march=*:-march=%*}\
137   %{mcpu=*:-mcpu=%*}\
138   %(cc1_subtarget)"
139 
140 /* For the cris-*-elf subtarget.  */
141 #define CRIS_CC1_SUBTARGET_SPEC \
142  "-melf\
143   %{mbest-lib-options:\
144    %{!moverride-best-lib-options:\
145    %{!march=*:%{!mcpu=*:-mtune=v" CRIS_DEFAULT_TUNE\
146        " -D__CRIS_arch_tune=" CRIS_DEFAULT_TUNE "}}\
147     %{!finhibit-size-directive:\
148       %{!fno-function-sections: -ffunction-sections}\
149       %{!fno-data-sections: -fdata-sections}}}}"
150 
151 /* This adds to CC1_SPEC.  */
152 #define CC1PLUS_SPEC ""
153 
154 #ifdef HAVE_AS_NO_MUL_BUG_ABORT_OPTION
155 #define MAYBE_AS_NO_MUL_BUG_ABORT \
156  "%{mno-mul-bug-workaround:-no-mul-bug-abort} " \
157  "%{mmul-bug-workaround:-mul-bug-abort} " \
158  "%{!mmul-bug-workaround:%{!mno-mul-bug-workaround:" MUL_BUG_ASM_DEFAULT "}} "
159 #else
160 #define MAYBE_AS_NO_MUL_BUG_ABORT
161 #endif
162 
163 /* Override previous definitions (../linux.h).  */
164 #undef ASM_SPEC
165 #define ASM_SPEC \
166  MAYBE_AS_NO_MUL_BUG_ABORT \
167  "%(asm_subtarget)\
168  %{march=*:%{mcpu=*:%edo not specify both -march=... and -mcpu=...}}\
169  %{march=v0|mcpu=v0|march=v3|mcpu=v3|march=v8|mcpu=v8:--march=v0_v10}\
170  %{march=v10|mcpu=v10:--march=v10}"
171 
172 /* For the cris-*-elf subtarget.  */
173 #define CRIS_ASM_SUBTARGET_SPEC \
174  "--em=criself %{!march=*:%{!mcpu=*:" CRIS_DEFAULT_ASM_ARCH_OPTION "}}"
175 
176 /* FIXME: We should propagate the -melf option to make the criself
177    "emulation" unless a linker script is provided (-T*), but I don't know
178    how to do that if either of -Ttext, -Tdata or -Tbss is given but no
179    linker script, as is usually the case.  Leave it to the user for the
180    time being.  */
181 #undef LINK_SPEC
182 #define LINK_SPEC \
183  "%{v:--verbose}\
184   %(link_subtarget)"
185 
186 /* For the cris-*-elf subtarget.  */
187 #define CRIS_LINK_SUBTARGET_SPEC \
188  "-mcriself\
189   %{sim2:%{!T*:-Tdata 0x4000000 -Tbss 0x8000000}}\
190   %{!r:%{O2|O3: --gc-sections}}"
191 
192 /* Which library to get.  The simulator uses a different library for
193    the low-level syscalls (implementing the Linux syscall ABI instead
194    of direct-iron accesses).  Default everything with the stub "nosys"
195    library.  */
196 /* Override previous definitions (linux.h).  */
197 #undef LIB_SPEC
198 #define LIB_SPEC \
199  "%{sim*:--start-group -lc -lsyslinux --end-group}\
200   %{!sim*:%{g*:-lg}\
201     %{!p:%{!pg:-lc}}%{p:-lc_p}%{pg:-lc_p} -lbsp}\
202   -lnosys"
203 
204 /* Linker startfile options; crt0 flavors.
205    We need to remove any previous definition (elfos.h).  */
206 #undef STARTFILE_SPEC
207 #define STARTFILE_SPEC \
208  "%{sim*:crt1.o%s}%{!sim*:crt0.o%s}\
209   crti.o%s crtbegin.o%s"
210 
211 #undef ENDFILE_SPEC
212 #define ENDFILE_SPEC "crtend.o%s crtn.o%s"
213 
214 #define EXTRA_SPECS                               \
215   {"cpp_subtarget", CRIS_CPP_SUBTARGET_SPEC},     \
216   {"cc1_subtarget", CRIS_CC1_SUBTARGET_SPEC},     \
217   {"asm_subtarget", CRIS_ASM_SUBTARGET_SPEC},     \
218   {"link_subtarget", CRIS_LINK_SUBTARGET_SPEC},   \
219   CRIS_SUBTARGET_EXTRA_SPECS
220 
221 #define CRIS_SUBTARGET_EXTRA_SPECS
222 
223 
224 /* Node: Run-time Target */
225 
226 #define TARGET_CPU_CPP_BUILTINS()                 \
227   do                                                        \
228     {                                                       \
229       builtin_define_std ("cris");                \
230       builtin_define_std ("CRIS");                \
231       builtin_define_std ("GNU_CRIS");            \
232       builtin_define ("__CRIS_ABI_version=2");    \
233       builtin_assert ("cpu=cris");                \
234       builtin_assert ("machine=cris");            \
235     }                                                       \
236   while (0)
237 
238 /* For the cris-*-elf subtarget.  */
239 #define CRIS_SUBTARGET_DEFAULT 0
240 
241 #define CRIS_CPU_BASE 0
242 #define CRIS_CPU_ETRAX4 3     /* Just lz added.  */
243 #define CRIS_CPU_SVINTO 8     /* Added swap, jsrc & Co., 32-bit accesses.  */
244 #define CRIS_CPU_NG 10                  /* Added mul[su].  */
245 
246 #ifndef TARGET_CPU_DEFAULT
247 #define TARGET_CPU_DEFAULT CRIS_CPU_BASE
248 #endif
249 
250 /* Default target_flags if no switches specified.
251    The alignment-by-32 is to make builtin atomic support for v10
252    work for *-elf for types without specified alignment (like plain
253    "int").  See top comment in sync.md.  */
254 #ifndef TARGET_DEFAULT
255 # if TARGET_CPU_DEFAULT == 10
256 #  define TARGET_DEFAULT \
257  (MASK_SIDE_EFFECT_PREFIXES + MASK_STACK_ALIGN \
258   + MASK_CONST_ALIGN + MASK_DATA_ALIGN \
259   + MASK_ALIGN_BY_32 \
260   + MASK_PROLOGUE_EPILOGUE)
261 # else  /* 0 */
262 #  define TARGET_DEFAULT \
263  (MASK_SIDE_EFFECT_PREFIXES + MASK_STACK_ALIGN \
264   + MASK_CONST_ALIGN + MASK_DATA_ALIGN \
265   + MASK_PROLOGUE_EPILOGUE)
266 # endif
267 #endif
268 
269 /* Don't depend on the assembler default setting for the errata machinery;
270    always pass the option to turn it on or off explicitly.  But, we have to
271    decide on which is the *GCC* default, and for that we should only need to
272    consider what's in TARGET_DEFAULT; no other changes should be necessary.  */
273 
274 #if (TARGET_DEFAULT & MASK_MUL_BUG)
275 #define MUL_BUG_ASM_DEFAULT "-mul-bug-abort"
276 #else
277 #define MUL_BUG_ASM_DEFAULT "-no-mul-bug-abort"
278 #endif
279 
280 /* Local, providing a default for cris_cpu_version.  */
281 #define CRIS_DEFAULT_CPU_VERSION TARGET_CPU_DEFAULT
282 
283 #define TARGET_HAS_MUL_INSNS (cris_cpu_version >= CRIS_CPU_NG)
284 #define TARGET_HAS_LZ (cris_cpu_version >= CRIS_CPU_ETRAX4)
285 #define TARGET_HAS_BREAK (cris_cpu_version >= CRIS_CPU_ETRAX4)
286 #define TARGET_HAS_SWAP (cris_cpu_version >= CRIS_CPU_SVINTO)
287 
288 /* The "break" instruction was introduced with ETRAX 4.  */
289 #define TARGET_TRAP_USING_BREAK8 \
290  (cris_trap_using_break8 == 2 ? TARGET_HAS_BREAK : cris_trap_using_break8)
291 
292 /* This condition controls whether to expand atomics inline or call
293    library functions. */
294 #define TARGET_ATOMICS_MAY_CALL_LIBFUNCS                    \
295  (cris_atomics_calling_libfunc != 2 && cris_atomics_calling_libfunc != 0)
296 
297 /* The < v10 atomics turn off interrupts, so they don't need alignment.
298    Incidentally, by default alignment is off there causing variables to
299    be default unaligned all over, so we'd have to make support
300    libraries use a proper atomic type (instead of "int"), one we'd
301    specify as aligned.  */
302 #define TARGET_TRAP_UNALIGNED_ATOMIC              \
303  (cris_trap_unaligned_atomic == 2                 \
304   ? cris_cpu_version == 10                        \
305   : cris_trap_unaligned_atomic)
306 
307 /* Node: Storage Layout */
308 
309 #define BITS_BIG_ENDIAN 0
310 
311 #define BYTES_BIG_ENDIAN 0
312 
313 /* WORDS_BIG_ENDIAN is not defined in the hardware, but for consistency,
314    we use little-endianness, and we may also be able to use
315    post-increment on DImode indirect.  */
316 #define WORDS_BIG_ENDIAN 0
317 
318 #define UNITS_PER_WORD 4
319 
320 #define CRIS_PROMOTED_MODE(MODE, UNSIGNEDP, TYPE) \
321  (GET_MODE_CLASS (MODE) == MODE_INT && GET_MODE_SIZE (MODE) < 4) \
322   ? SImode : MODE
323 
324 /* We will be using prototype promotion, so they will be 32 bit.  */
325 #define PARM_BOUNDARY 32
326 
327 /* Stack boundary is guided by -mstack-align, -mno-stack-align,
328    -malign.
329    Old comment: (2.1: still valid in 2.7.2?)
330     Note that to make this macro affect the alignment of stack
331    locals, a fix was required, and special precautions when handling
332    the stack pointer in various other macros (TARGET_ASM_FUNCTION_PROLOGUE
333    et al) were required.  See file "function.cc".  If you would just define
334    this macro, it would only affect the builtin alloca and variable
335    local data (non-ANSI, non-K&R, Gnu C extension).  */
336 #define STACK_BOUNDARY \
337  (TARGET_STACK_ALIGN ? (TARGET_ALIGN_BY_32 ? 32 : 16) : 8)
338 
339 #define FUNCTION_BOUNDARY 16
340 
341 /* Do not change BIGGEST_ALIGNMENT (when optimizing), as it will affect
342    strange places, at least in 2.1.  */
343 #define BIGGEST_ALIGNMENT 8
344 
345 /* If -m16bit,      -m16-bit, -malign or -mdata-align,
346    align everything to 16 bit.  */
347 #define DATA_ALIGNMENT(TYPE, BASIC_ALIGN)                             \
348  (TARGET_DATA_ALIGN                                                   \
349   ? (TARGET_ALIGN_BY_32                                                         \
350      ? (BASIC_ALIGN < 32 ? 32 : BASIC_ALIGN)                          \
351      : (BASIC_ALIGN < 16 ? 16 : BASIC_ALIGN)) : BASIC_ALIGN)
352 
353 /* FIXME: Define LOCAL_ALIGNMENT for word and dword or arrays and
354    structures (if -mstack-align=), and check that it is good.  */
355 
356 #define EMPTY_FIELD_BOUNDARY 8
357 
358 #define STRUCTURE_SIZE_BOUNDARY 8
359 
360 #define STRICT_ALIGNMENT 0
361 
362 /* Remove any previous definition (elfos.h).
363    ??? If it wasn't for all the other stuff that affects layout of
364    structures and bit-fields, this could presumably cause incompatibility
365    with other GNU/Linux ports (i.e. elfos.h users).  */
366 #undef PCC_BITFIELD_TYPE_MATTERS
367 
368 
369 /* Node: Type Layout */
370 
371 /* Note that DOUBLE_TYPE_SIZE is not defined anymore, since the default
372    value gives a 64-bit double, which is what we now use.  */
373 
374 /* For compatibility and historical reasons, a char should be signed.  */
375 #define DEFAULT_SIGNED_CHAR 1
376 
377 /* Note that WCHAR_TYPE_SIZE is used in cexp.y,
378    where TARGET_SHORT is not available.  */
379 #undef WCHAR_TYPE
380 #define WCHAR_TYPE "long int"
381 
382 #undef WCHAR_TYPE_SIZE
383 #define WCHAR_TYPE_SIZE 32
384 
385 
386 /* Node: Register Basics */
387 
388 /*  We count all 16 non-special registers, SRP, a faked argument
389     pointer register, MOF, CCR/DCCR, and the faked frame-pointer.  */
390 #define FIRST_PSEUDO_REGISTER (16 + 1 + 1 + 1 + 1 + 1)
391 
392 /* For CRIS, these are r15 (pc) and r14 (sp). Register r8 is used as a
393    frame-pointer, but is not fixed.  SRP is not included in general
394    registers and will not be used automatically.  All other special
395    registers are fixed at the moment.  The faked argument pointer register
396    is fixed too.  */
397 #define FIXED_REGISTERS \
398  {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 1}
399 
400 /* Register r9 is used for structure-address, r10-r13 for parameters,
401    r10- for return values.  */
402 #define CALL_USED_REGISTERS \
403  {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1}
404 
405 /* Node: Allocation Order */
406 
407 /* We need this on CRIS, because call-used regs should be used first,
408    (so we don't need to push).  Else start using registers from r0 and up.
409     This preference is mainly because if we put call-used-regs from r0
410    and up, then we can't use movem to push the rest, (which have to be
411    saved if we use them, and movem has to start with r0).
412    Change here if you change which registers to use as call registers.
413 
414    The actual need to explicitly prefer call-used registers improved the
415    situation a lot for 2.1, but might not actually be needed anymore.
416    Still, this order reflects what GCC should find out by itself, so it
417    probably does not hurt.
418 
419    Order of preference: Call-used-regs first, then r0 and up, last fp &
420    sp & pc as fillers.
421    Call-used regs in opposite order, so they will cause less conflict if
422    a function has few args (<= 3) and it wants a scratch reg.
423     Use struct-return address first, since very few functions use
424    structure return values so it is likely to be available.  */
425 #define REG_ALLOC_ORDER \
426  {9, 13, 12, 11, 10, 0, 1, 2, 3, 4, 5, 6, 7, 8, 14, 15, 17, 16, 18, 19,         \
427   20}
428 
429 
430 /* Node: Leaf Functions */
431 /* (no definitions) */
432 
433 /* Node: Stack Registers */
434 /* (no definitions) */
435 
436 
437 /* Node: Register Classes */
438 
439 /* It's not obvious, but having subunions of all movable-between
440    register classes does really help register allocation (pre-IRA
441    comment).  */
442 enum reg_class
443   {
444     NO_REGS,
445     MOF_REGS, SRP_REGS, CC0_REGS,
446     MOF_SRP_REGS, SPECIAL_REGS,
447     GENERAL_REGS,
448     ALL_REGS,
449     LIM_REG_CLASSES
450   };
451 
452 #define N_REG_CLASSES (int) LIM_REG_CLASSES
453 
454 #define REG_CLASS_NAMES                                                         \
455   {"NO_REGS",                                                                   \
456    "MOF_REGS", "SRP_REGS", "CC0_REGS",                                \
457    "MOF_SRP_REGS", "SPECIAL_REGS",                                    \
458    "GENERAL_REGS", "ALL_REGS"}
459 
460 #define CRIS_SPECIAL_REGS_CONTENTS                                              \
461  ((1 << CRIS_SRP_REGNUM) | (1 << CRIS_MOF_REGNUM) | (1 << CRIS_CC0_REGNUM))
462 
463 #define CRIS_FAKED_REGS_CONTENTS \
464  ((1 << CRIS_AP_REGNUM) | (1 << CRIS_FP_REGNUM))
465 
466 /* Count in the faked argument register in GENERAL_REGS.  Keep out SRP.  */
467 #define REG_CLASS_CONTENTS                        \
468   {                                                         \
469    {0},                                                     \
470    {1 << CRIS_MOF_REGNUM},                        \
471    {1 << CRIS_SRP_REGNUM},                        \
472    {1 << CRIS_CC0_REGNUM},                        \
473    {(1 << CRIS_MOF_REGNUM)                        \
474     | (1 << CRIS_SRP_REGNUM)},                              \
475    {CRIS_SPECIAL_REGS_CONTENTS},                  \
476    {0xffff | CRIS_FAKED_REGS_CONTENTS},           \
477    {0xffff | CRIS_FAKED_REGS_CONTENTS             \
478     | CRIS_SPECIAL_REGS_CONTENTS}                 \
479   }
480 
481 #define REGNO_REG_CLASS(REGNO)                              \
482   ((REGNO) == CRIS_MOF_REGNUM ? MOF_REGS :        \
483    (REGNO) == CRIS_SRP_REGNUM ? SRP_REGS :        \
484    (REGNO) == CRIS_CC0_REGNUM ? CC0_REGS :        \
485    GENERAL_REGS)
486 
487 #define BASE_REG_CLASS GENERAL_REGS
488 
489 #define INDEX_REG_CLASS GENERAL_REGS
490 
491 /* Since it uses reg_renumber, it is safe only once reg_renumber
492    has been allocated, which happens in reginfo.cc during register
493    allocation.  */
494 #define REGNO_OK_FOR_BASE_P(REGNO)                                              \
495  ((REGNO) <= CRIS_LAST_GENERAL_REGISTER                                         \
496   || (REGNO) == FRAME_POINTER_REGNUM                                            \
497   || (REGNO) == ARG_POINTER_REGNUM                                              \
498   || (unsigned) reg_renumber[REGNO] <= CRIS_LAST_GENERAL_REGISTER     \
499   || (unsigned) reg_renumber[REGNO] == FRAME_POINTER_REGNUM           \
500   || (unsigned) reg_renumber[REGNO] == ARG_POINTER_REGNUM)
501 
502 /* See REGNO_OK_FOR_BASE_P.  */
503 #define REGNO_OK_FOR_INDEX_P(REGNO) REGNO_OK_FOR_BASE_P(REGNO)
504 
505 /* We can't move special registers to and from memory in smaller than
506    word_mode.  We also can't move between special registers.  Luckily,
507    -1, as returned by true_regnum for non-sub/registers, is valid as a
508    parameter to our REGNO_REG_CLASS, returning GENERAL_REGS, so we get
509    the effect that any X that isn't a special-register is treated as
510    a non-empty intersection with GENERAL_REGS.  */
511 #define SECONDARY_RELOAD_CLASS(CLASS, MODE, X)                                  \
512  ((reg_class_subset_p (CLASS, SPECIAL_REGS)                                     \
513    && ((GET_MODE_SIZE (MODE) < 4 && MEM_P (X))                                  \
514        || !reg_classes_intersect_p (REGNO_REG_CLASS (true_regnum (X)),          \
515                                             GENERAL_REGS)))                     \
516    ? GENERAL_REGS : NO_REGS)
517 
518 /* For CRIS, this is always the size of MODE in words,
519    since all registers are the same size.  To use omitted modes in
520    patterns with reload constraints, you must say the widest size
521    which is allowed for VOIDmode.
522    FIXME:  Does that still apply for gcc-2.9x?  Keep poisoned until such
523    patterns are added back.  News: 2001-03-16: Happens as early as the
524    underscore-test.  */
525 #define CLASS_MAX_NREGS(CLASS, MODE)                                            \
526  ((MODE) == VOIDmode                                                                      \
527   ? 1 /* + cris_fatal ("CLASS_MAX_NREGS with VOIDmode")     */                  \
528   : ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD))
529 
530 
531 /* Node: Frame Layout */
532 
533 #define STACK_GROWS_DOWNWARD 1
534 #define FRAME_GROWS_DOWNWARD 1
535 
536 #define FIRST_PARM_OFFSET(FNDECL) 0
537 
538 #define RETURN_ADDR_RTX(COUNT, FRAMEADDR) \
539  cris_return_addr_rtx (COUNT, FRAMEADDR)
540 
541 #define INCOMING_RETURN_ADDR_RTX gen_rtx_REG (Pmode, CRIS_SRP_REGNUM)
542 
543 /* FIXME: Any __builtin_eh_return callers must not return anything and
544    there must not be collisions with incoming parameters.  Luckily the
545    number of __builtin_eh_return callers is limited.  For now return
546    parameter registers in reverse order and hope for the best.  */
547 #define EH_RETURN_DATA_REGNO(N) \
548   (IN_RANGE ((N), 0, 3) ? (CRIS_FIRST_ARG_REG + 3 - (N)) : INVALID_REGNUM)
549 
550 /* Store the stack adjustment in the structure-return-address register.  */
551 #define CRIS_STACKADJ_REG CRIS_STRUCT_VALUE_REGNUM
552 #define EH_RETURN_STACKADJ_RTX gen_rtx_REG (SImode, CRIS_STACKADJ_REG)
553 
554 #define EH_RETURN_HANDLER_RTX \
555   cris_return_addr_rtx (0, NULL)
556 
557 #define INIT_EXPANDERS cris_init_expanders ()
558 
559 /* FIXME: Move this to right node (it's not documented properly yet).  */
560 #define DWARF_FRAME_RETURN_COLUMN DWARF_FRAME_REGNUM (CRIS_SRP_REGNUM)
561 
562 /* FIXME: Move this to right node (it's not documented properly yet).
563    FIXME: Check what alignment we can assume regarding
564    TARGET_STACK_ALIGN and TARGET_ALIGN_BY_32.  */
565 #define DWARF_CIE_DATA_ALIGNMENT -1
566 
567 /* If we would ever need an exact mapping between canonical register
568    number and dwarf frame register, we would either need to include all
569    registers in the gcc description (with some marked fixed of course), or
570    an inverse mapping from dwarf register to gcc register.  There is one
571    need in dwarf2out.cc:expand_builtin_init_dwarf_reg_sizes.  Right now, I
572    don't see that we need exact correspondence between DWARF *frame*
573    registers and DBX_REGISTER_NUMBER, so map them onto GCC registers.  */
574 #define DWARF_FRAME_REGNUM(REG) (REG)
575 
576 /* Node: Stack Checking */
577 /* (no definitions) FIXME: Check.  */
578 
579 /* Node: Frame Registers */
580 
581 #define STACK_POINTER_REGNUM CRIS_SP_REGNUM
582 
583 /* Register used for frame pointer.  This is also the last of the saved
584    registers, when a frame pointer is not used.  */
585 #define HARD_FRAME_POINTER_REGNUM CRIS_REAL_FP_REGNUM
586 
587 /* Faked register, is always eliminated to at least CRIS_REAL_FP_REGNUM.  */
588 #define FRAME_POINTER_REGNUM CRIS_FP_REGNUM
589 
590 /* Faked register, is always eliminated.  We need it to eliminate
591    allocating stack slots for the return address and the frame pointer.  */
592 #define ARG_POINTER_REGNUM CRIS_AP_REGNUM
593 
594 #define STATIC_CHAIN_REGNUM CRIS_STATIC_CHAIN_REGNUM
595 
596 /* No unwind context is needed for faked registers nor DCCR.  Currently not MOF
597    too, but let's keep that open.  */
598 #define DWARF_FRAME_REGISTERS (CRIS_MOF_REGNUM + 1)
599 
600 /* Node: Elimination */
601 
602 #define ELIMINABLE_REGS                                     \
603  {{ARG_POINTER_REGNUM, STACK_POINTER_REGNUM},     \
604   {ARG_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM},          \
605   {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM},   \
606   {FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}}
607 
608 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
609  (OFFSET) = cris_initial_elimination_offset (FROM, TO)
610 
611 
612 /* Node: Stack Arguments */
613 
614 /* Since many parameters take up one register each in any case,
615    defining TARGET_PROMOTE_PROTOTYPES that always returns true would
616    seem like a good idea, but measurements indicate that a combination
617    using PROMOTE_MODE is better.  */
618 
619 #define ACCUMULATE_OUTGOING_ARGS 1
620 
621 
622 /* Node: Register Arguments */
623 
624 /* Contrary to what you'd believe, defining FUNCTION_ARG_CALLEE_COPIES
625    seems like a (small total) loss, at least for gcc-2.7.2 compiling and
626    running gcc-2.1 (small win in size, small loss running -- 100.1%),
627    and similarly for size for products (.1 .. .3% bloat, sometimes win).
628    Due to the empirical likeliness of making slower code, it is not
629    defined.  */
630 
631 /* This no longer *needs* to be a structure; but keeping it as such should
632    not hurt (and hacking the ABI is simpler).  */
633 #define CUMULATIVE_ARGS struct cum_args
634 struct cum_args {int regs;};
635 
636 /* The regs member is an integer, the number of arguments got into
637    registers so far.  */
638 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, FNDECL, N_NAMED_ARGS) \
639  ((CUM).regs = 0)
640 
641 #define FUNCTION_ARG_REGNO_P(REGNO)                         \
642  ((REGNO) >= CRIS_FIRST_ARG_REG                                       \
643   && (REGNO) < CRIS_FIRST_ARG_REG + (CRIS_MAX_ARGS_IN_REGS))
644 
645 
646 /* Node: Aggregate Return */
647 
648 #define CRIS_STRUCT_VALUE_REGNUM ((CRIS_FIRST_ARG_REG) - 1)
649 
650 
651 /* Node: Caller Saves */
652 /* (no definitions) */
653 
654 /* Node: Function entry */
655 
656 /* See cris.cc for TARGET_ASM_FUNCTION_PROLOGUE and
657    TARGET_ASM_FUNCTION_EPILOGUE.  */
658 
659 /* Node: Profiling */
660 
661 #define FUNCTION_PROFILER(FILE, LABELNO)  \
662  error ("no %<FUNCTION_PROFILER%> for CRIS")
663 
664 /* FIXME: Some of the undefined macros might be mandatory.  If so, fix
665    documentation.  */
666 
667 
668 /* Node: Trampolines */
669 
670 #define TRAMPOLINE_SIZE 32
671 
672 /* CRIS wants instructions on word-boundary.  */
673 #define TRAMPOLINE_ALIGNMENT 16
674 
675 /* Node: Library Calls */
676 
677 /* If you change this, you have to check whatever libraries and systems
678    that use it.  */
679 #define TARGET_EDOM 33
680 
681 
682 /* Node: Addressing Modes */
683 
684 #define HAVE_POST_INCREMENT 1
685 
686 #define CONSTANT_ADDRESS_P(X) \
687   (CONSTANT_P (X) && cris_legitimate_address_p (QImode, X, false))
688 
689 #define MAX_REGS_PER_ADDRESS 2
690 
691 /* Fix reloads known to cause suboptimal spilling.  */
692 #define LEGITIMIZE_RELOAD_ADDRESS(X, MODE, OPNUM, TYPE, INDL, WIN)    \
693   do                                                                                      \
694     {                                                                                     \
695       if (cris_reload_address_legitimized (X, MODE, OPNUM, TYPE, INDL))         \
696           goto WIN;                                                             \
697     }                                                                                     \
698   while (0)
699 
700 
701 /* Node: Condition Code */
702 
703 /* FIXME: Maybe define TARGET_CANONICALIZE_COMPARISON later, when
704    playing with optimizations.  */
705 
706 #define SELECT_CC_MODE(op, x, y) cris_select_cc_mode(op, x, y)
707 
708 #define REVERSIBLE_CC_MODE(MODE) true
709 
710 /* No known need to define REVERSE_CONDITION, the default is good.  */
711 
712 /* Node: Costs */
713 
714 /* Regardless of the presence of delay slots, the default value of 1 for
715    BRANCH_COST is the best in the range (1, 2, 3), tested with gcc-2.7.2
716    with testcases ipps and gcc, giving smallest and fastest code.  */
717 
718 #define SLOW_BYTE_ACCESS 0
719 
720 /* This is the threshold *below* which inline move sequences of
721    word-length sizes will be emitted.  The "9" will translate to
722    (9 - 1) * 4 = 32 bytes maximum moved, but using 16 instructions
723    (8 instruction sequences) or less.  */
724 #define MOVE_RATIO(speed) 9
725 
726 
727 /* Node: Sections */
728 
729 #define TEXT_SECTION_ASM_OP "\t.text"
730 
731 #define DATA_SECTION_ASM_OP "\t.data"
732 
733 /* The jump table is immediately connected to the preceding insn.  */
734 #define JUMP_TABLES_IN_TEXT_SECTION 1
735 
736 
737 /* Node: File Framework */
738 
739 /* We don't want an .ident for gcc.  To avoid that but still support
740    #ident, we override TARGET_ASM_OUTPUT_IDENT and, since the gcc .ident
741    is its only use besides front-end .ident directives, we return if
742    the state if the cgraph is not PARSING.  */
743 #undef TARGET_ASM_OUTPUT_IDENT
744 #define TARGET_ASM_OUTPUT_IDENT cris_asm_output_ident
745 
746 #define ASM_APP_ON "#APP\n"
747 
748 #define ASM_APP_OFF "#NO_APP\n"
749 
750 
751 /* Node: Data Output */
752 
753 #define IS_ASM_LOGICAL_LINE_SEPARATOR(C, STR) (C) == '@'
754 
755 /* Node: Uninitialized Data */
756 
757 /* Remember to round off odd values if we want data alignment,
758    since we cannot do that with an .align directive.
759 
760    Using .comm causes the space not to be reserved in .bss, but by
761    tricks with the symbol type.  Not good if other tools than binutils
762    are used on the object files.  Since ".global ... .lcomm ..." works, we
763    use that.  Use .._ALIGNED_COMMON, since gcc whines when we only have
764    ..._COMMON, and we prefer to whine ourselves; BIGGEST_ALIGNMENT is not
765    the one to check.  */
766 /* FIXME: I suspect a bug in gcc with alignment.  Do not warn until
767    investigated; it mucks up the testsuite results.  */
768 #define CRIS_ASM_OUTPUT_ALIGNED_DECL_COMMON(FILE, DECL, NAME, SIZE, ALIGN, LOCAL) \
769   do                                                                                      \
770     {                                                                                     \
771       int align_ = (ALIGN) / BITS_PER_UNIT;                                     \
772       if (TARGET_DATA_ALIGN && TARGET_ALIGN_BY_32 && align_ < 4)      \
773           align_ = 4;                                                                     \
774       else if (TARGET_DATA_ALIGN && align_ < 2)                                 \
775           align_ = 2;                                                                     \
776       /* FIXME: Do we need this?  */                                            \
777       else if (align_ < 1)                                                      \
778           align_ = 1;                                                                     \
779                                                                                           \
780       if (LOCAL)                                                                \
781           {                                                                               \
782             fprintf ((FILE), "%s", LOCAL_ASM_OP);                               \
783             assemble_name ((FILE), (NAME));                                     \
784             fprintf ((FILE), "\n");                                             \
785           }                                                                               \
786       fprintf ((FILE), "%s", COMMON_ASM_OP);                                    \
787       assemble_name ((FILE), (NAME));                                           \
788       fprintf ((FILE), ",%u,%u\n", (int)(SIZE), align_);              \
789     }                                                                                     \
790   while (0)
791 
792 #define ASM_OUTPUT_ALIGNED_DECL_COMMON(FILE, DECL, NAME, SIZE, ALIGN) \
793  CRIS_ASM_OUTPUT_ALIGNED_DECL_COMMON(FILE, DECL, NAME, SIZE, ALIGN, 0)
794 
795 #undef ASM_OUTPUT_ALIGNED_DECL_LOCAL
796 #define ASM_OUTPUT_ALIGNED_DECL_LOCAL(FILE, DECL, NAME, SIZE, ALIGN) \
797  CRIS_ASM_OUTPUT_ALIGNED_DECL_COMMON(FILE, DECL, NAME, SIZE, ALIGN, 1)
798 
799 /* Node: Label Output */
800 
801 /* Globalizing directive for a label.  */
802 #define GLOBAL_ASM_OP "\t.global "
803 
804 #define SUPPORTS_WEAK 1
805 
806 #define ASM_OUTPUT_SYMBOL_REF(STREAM, SYM) \
807  cris_asm_output_symbol_ref (STREAM, SYM)
808 
809 #define ASM_OUTPUT_LABEL_REF(STREAM, BUF) \
810  cris_asm_output_label_ref (STREAM, BUF)
811 
812 /* Remove any previous definition (elfos.h).  */
813 #undef ASM_GENERATE_INTERNAL_LABEL
814 #define ASM_GENERATE_INTERNAL_LABEL(LABEL, PREFIX, NUM)     \
815   sprintf (LABEL, "*%s%s%ld", LOCAL_LABEL_PREFIX, PREFIX, (long) NUM)
816 
817 /* Node: Initialization */
818 /* (no definitions) */
819 
820 /* Node: Macros for Initialization */
821 /* (no definitions) */
822 
823 /* Node: Instruction Output */
824 
825 #define REGISTER_NAMES                                                \
826  {"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8",     \
827   "r9", "r10", "r11", "r12", "r13", "sp", "pc", "srp",      \
828   "mof", "faked_ap", "dccr", "faked_fp"}
829 
830 #define ADDITIONAL_REGISTER_NAMES \
831  {{"r14", 14}, {"r15", 15}}
832 
833 /* Output an empty line to illustrate the presence of the delay slot.  */
834 #define DBR_OUTPUT_SEQEND(FILE) \
835   fprintf (FILE, "\n")
836 
837 #define LOCAL_LABEL_PREFIX "."
838 
839 /* cppinit.c initializes a const array from this, so it must be constant,
840    can't have it different based on options.  Luckily, the prefix is
841    always allowed, so let's have it on all GCC-generated code.  Note that
842    we have this verbatim everywhere in the back-end, not using %R or %s or
843    such.  */
844 #define REGISTER_PREFIX "$"
845 
846 /* Remove any previous definition (elfos.h).  */
847 /* We use -fno-leading-underscore to remove it, when necessary.  */
848 #undef USER_LABEL_PREFIX
849 #define USER_LABEL_PREFIX "_"
850 
851 #define ASM_OUTPUT_REG_PUSH(FILE, REGNO)                                        \
852   fprintf (FILE, "\tpush $%s\n", reg_names[REGNO])
853 
854 #define ASM_OUTPUT_REG_POP(FILE, REGNO) \
855   fprintf (FILE, "\tmove [$sp+],$%s\n", reg_names[REGNO])
856 
857 
858 /* Node: Dispatch Tables */
859 
860 #define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, BODY, VALUE, REL)              \
861   asm_fprintf (FILE, "\t.word %LL%d-%LL%d\n", VALUE, REL)
862 
863 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE)  \
864   asm_fprintf (FILE, "\t.dword %LL%d\n", VALUE)
865 
866 /* Defined to also emit an .align in elfos.h.  We don't want that.  */
867 #undef ASM_OUTPUT_CASE_LABEL
868 
869 /* Since the "bound" insn loads the comparison value if the compared<
870    value (register) is out of bounds (0..comparison value-1), we need
871    to output another case to catch it.
872    The way to find it is to look for the label_ref at the else-arm inside
873    the expanded casesi core-insn.
874    FIXME: Check this construct when changing to new version of gcc.  */
875 #define ASM_OUTPUT_CASE_END(STREAM, NUM, TABLE)                                 \
876   cris_asm_output_case_end (STREAM, NUM, TABLE)
877 
878 
879 /* Node: Exception Region Output */
880 /* (no definitions) */
881 /* FIXME: Fill in with our own optimized layout.  */
882 
883 /* Node: Alignment Output */
884 
885 #define ASM_OUTPUT_ALIGN(FILE, LOG)  \
886  fprintf (FILE, "\t.align %d\n", (LOG))
887 
888 
889 /* Node: All Debuggers */
890 
891 #define DBX_REGISTER_NUMBER(REGNO)                                    \
892  ((REGNO) == CRIS_SRP_REGNUM ? CRIS_CANONICAL_SRP_REGNUM :  \
893   (REGNO) == CRIS_MOF_REGNUM ? CRIS_CANONICAL_MOF_REGNUM :  \
894   (REGNO) == CRIS_CC0_REGNUM ? CRIS_CANONICAL_CC0_REGNUM :  \
895  (REGNO))
896 
897 /* FIXME: Investigate DEBUGGER_AUTO_OFFSET, DEBUGGER_ARG_OFFSET.  */
898 
899 
900 /* Node: DWARF */
901 /* (no definitions) */
902 
903 /* Node: Misc */
904 
905 /* A combination of the bound (umin) insn together with a
906    sign-extended add via the table to PC seems optimal.
907    If the table overflows, the assembler will take care of it.
908    Theoretically, in extreme cases (uncertain if they occur), an error
909    will be emitted, so FIXME: Check how large case-tables are emitted,
910    possible add an option to emit SImode case-tables.  */
911 #define CASE_VECTOR_MODE HImode
912 
913 #define CASE_VECTOR_PC_RELATIVE 1
914 
915 /* FIXME: Investigate CASE_VECTOR_SHORTEN_MODE to make sure HImode is not
916    used when broken-.word could possibly fail (plus testcase).  */
917 
918 /* This is the number of bytes that can be moved in one
919    reasonably fast instruction sequence.  For CRIS, this is two
920    instructions: mem => reg, reg => mem.  */
921 #define MOVE_MAX 4
922 
923 /* Maybe SHIFT_COUNT_TRUNCATED is safe to define?  FIXME: Check later.  */
924 
925 #define CLZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) ((VALUE) = 32, 1)
926 #define CTZ_DEFINED_VALUE_AT_ZERO(MODE, VALUE) ((VALUE) = 32, 1)
927 
928 #define Pmode SImode
929 
930 #define FUNCTION_MODE QImode
931 
932 /*
933  * Local variables:
934  * eval: (c-set-style "gnu")
935  * indent-tabs-mode: t
936  * End:
937  */
938