xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/config/vax/vax.h (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
1 /* Definitions of target machine for GNU compiler.  VAX version.
2    Copyright (C) 1987, 1988, 1991, 1993, 1994, 1995, 1996, 1997, 1998,
3    1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4    Free Software Foundation, Inc.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
11 any later version.
12 
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 GNU General Public License for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.  */
21 
22 
23 /* Target CPU builtins.  */
24 #define TARGET_CPU_CPP_BUILTINS()		\
25   do						\
26     {						\
27       builtin_define ("__vax__");		\
28       builtin_assert ("cpu=vax");		\
29       builtin_assert ("machine=vax");		\
30       if (TARGET_G_FLOAT)			\
31 	{					\
32 	  builtin_define ("__GFLOAT");		\
33 	  builtin_define ("__GFLOAT__");	\
34 	}					\
35     }						\
36   while (0)
37 
38 #define VMS_TARGET 0
39 
40 /* Use -J option for long branch support with Unix assembler.  */
41 
42 #define ASM_SPEC "-J"
43 
44 /* Choose proper libraries depending on float format.
45    Note that there are no profiling libraries for g-format.
46    Also use -lg for the sake of dbx.  */
47 
48 #define LIB_SPEC "%{g:-lg}\
49  %{mg:%{lm:-lmg} -lcg \
50   %{p:%eprofiling not supported with -mg\n}\
51   %{pg:%eprofiling not supported with -mg\n}}\
52  %{!mg:%{!p:%{!pg:-lc}}%{p:-lc_p}%{pg:-lc_p}}"
53 
54 /* Print subsidiary information on the compiler version in use.  */
55 
56 #ifndef TARGET_NAME	/* A more specific value might be supplied via -D.  */
57 #define TARGET_NAME "vax"
58 #endif
59 #define TARGET_VERSION fprintf (stderr, " (%s)", TARGET_NAME)
60 
61 /* Run-time compilation parameters selecting different hardware subsets.  */
62 
63 /* Nonzero if ELF.  Redefined by vax/elf.h.  */
64 #define TARGET_ELF 0
65 
66 /* Use BSD names for udiv and umod libgcc calls.  */
67 #define TARGET_BSD_DIVMOD 1
68 
69 /* Default target_flags if no switches specified.  */
70 
71 #ifndef TARGET_DEFAULT
72 #define TARGET_DEFAULT (MASK_UNIX_ASM)
73 #endif
74 
75 #define OVERRIDE_OPTIONS override_options ()
76 
77 
78 /* Target machine storage layout */
79 
80 /* Define this if most significant bit is lowest numbered
81    in instructions that operate on numbered bit-fields.
82    This is not true on the VAX.  */
83 #define BITS_BIG_ENDIAN 0
84 
85 /* Define this if most significant byte of a word is the lowest numbered.  */
86 /* That is not true on the VAX.  */
87 #define BYTES_BIG_ENDIAN 0
88 
89 /* Define this if most significant word of a multiword number is the lowest
90    numbered.  */
91 /* This is not true on the VAX.  */
92 #define WORDS_BIG_ENDIAN 0
93 
94 /* Width of a word, in units (bytes).  */
95 #define UNITS_PER_WORD 4
96 
97 /* Allocation boundary (in *bits*) for storing arguments in argument list.  */
98 #define PARM_BOUNDARY 32
99 
100 /* Allocation boundary (in *bits*) for the code of a function.  */
101 #define FUNCTION_BOUNDARY 16
102 
103 /* Alignment of field after `int : 0' in a structure.  */
104 #define EMPTY_FIELD_BOUNDARY (TARGET_VAXC_ALIGNMENT ? 8 : 32)
105 
106 /* Every structure's size must be a multiple of this.  */
107 #define STRUCTURE_SIZE_BOUNDARY 8
108 
109 /* A bit-field declared as `int' forces `int' alignment for the struct.  */
110 #define PCC_BITFIELD_TYPE_MATTERS (! TARGET_VAXC_ALIGNMENT)
111 
112 /* No data type wants to be aligned rounder than this.  */
113 #define BIGGEST_ALIGNMENT 32
114 
115 /* No structure field wants to be aligned rounder than this.  */
116 #define BIGGEST_FIELD_ALIGNMENT (TARGET_VAXC_ALIGNMENT ? 8 : 32)
117 
118 /* Set this nonzero if move instructions will actually fail to work
119    when given unaligned data.  */
120 #define STRICT_ALIGNMENT 0
121 
122 /* Let's keep the stack somewhat aligned.  */
123 #define STACK_BOUNDARY 32
124 
125 /* The table of an ADDR_DIFF_VEC must be contiguous with the case
126    opcode, it is part of the case instruction.  */
127 #define ADDR_VEC_ALIGN(ADDR_VEC) 0
128 
129 /* Standard register usage.  */
130 
131 /* Number of actual hardware registers.
132    The hardware registers are assigned numbers for the compiler
133    from 0 to just below FIRST_PSEUDO_REGISTER.
134    All registers that the compiler knows about must be given numbers,
135    even those that are not normally considered general registers.  */
136 #define FIRST_PSEUDO_REGISTER 16
137 
138 /* 1 for registers that have pervasive standard uses
139    and are not available for the register allocator.
140    On the VAX, these are the AP, FP, SP and PC.  */
141 #define FIXED_REGISTERS {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1}
142 
143 /* 1 for registers not available across function calls.
144    These must include the FIXED_REGISTERS and also any
145    registers that can be used without being saved.
146    The latter must include the registers where values are returned
147    and the register where structure-value addresses are passed.
148    Aside from that, you can include as many other registers as you like.  */
149 #define CALL_USED_REGISTERS {1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1}
150 
151 /* Return number of consecutive hard regs needed starting at reg REGNO
152    to hold something of mode MODE.
153    This is ordinarily the length in words of a value of mode MODE
154    but can be less for certain modes in special long registers.
155    On the VAX, all registers are one word long.  */
156 #define HARD_REGNO_NREGS(REGNO, MODE)	\
157   ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
158 
159 /* Value is 1 if hard register REGNO can hold a value of machine-mode MODE.
160    On the VAX, all registers can hold all modes.  */
161 #define HARD_REGNO_MODE_OK(REGNO, MODE) 1
162 
163 /* Value is 1 if it is a good idea to tie two pseudo registers
164    when one has mode MODE1 and one has mode MODE2.
165    If HARD_REGNO_MODE_OK could produce different values for MODE1 and MODE2,
166    for any hard reg, then this must be 0 for correct output.  */
167 #define MODES_TIEABLE_P(MODE1, MODE2)  1
168 
169 /* Specify the registers used for certain standard purposes.
170    The values of these macros are register numbers.  */
171 
172 /* VAX pc is overloaded on a register.  */
173 #define PC_REGNUM VAX_PC_REGNUM
174 
175 /* Register to use for pushing function arguments.  */
176 #define STACK_POINTER_REGNUM VAX_SP_REGNUM
177 
178 /* Base register for access to local variables of the function.  */
179 #define FRAME_POINTER_REGNUM VAX_FP_REGNUM
180 
181 /* Offset from the frame pointer register value to the top of stack.  */
182 #define FRAME_POINTER_CFA_OFFSET(FNDECL) 0
183 
184 /* Base register for access to arguments of the function.  */
185 #define ARG_POINTER_REGNUM VAX_AP_REGNUM
186 
187 /* Register in which static-chain is passed to a function.  */
188 #define STATIC_CHAIN_REGNUM 0
189 
190 /* Register in which address to store a structure value
191    is passed to a function.  */
192 #define VAX_STRUCT_VALUE_REGNUM 1
193 
194 /* Define the classes of registers for register constraints in the
195    machine description.  Also define ranges of constants.
196 
197    One of the classes must always be named ALL_REGS and include all hard regs.
198    If there is more than one class, another class must be named NO_REGS
199    and contain no registers.
200 
201    The name GENERAL_REGS must be the name of a class (or an alias for
202    another name such as ALL_REGS).  This is the class of registers
203    that is allowed by "g" or "r" in a register constraint.
204    Also, registers outside this class are allocated only when
205    instructions express preferences for them.
206 
207    The classes must be numbered in nondecreasing order; that is,
208    a larger-numbered class must never be contained completely
209    in a smaller-numbered class.
210 
211    For any two classes, it is very desirable that there be another
212    class that represents their union.  */
213 
214 /* The VAX has only one kind of registers, so NO_REGS and ALL_REGS
215    are the only classes.  */
216 
217 enum reg_class { NO_REGS, ALL_REGS, LIM_REG_CLASSES };
218 
219 #define N_REG_CLASSES (int) LIM_REG_CLASSES
220 
221 /* Since GENERAL_REGS is the same class as ALL_REGS,
222    don't give it a different class number; just make it an alias.  */
223 
224 #define GENERAL_REGS ALL_REGS
225 
226 /* Give names of register classes as strings for dump file.  */
227 
228 #define REG_CLASS_NAMES	\
229   { "NO_REGS", "ALL_REGS" }
230 
231 /* The following macro defines cover classes for Integrated Register
232    Allocator.  Cover classes is a set of non-intersected register
233    classes covering all hard registers used for register allocation
234    purpose.  Any move between two registers of a cover class should be
235    cheaper than load or store of the registers.  The macro value is
236    array of register classes with LIM_REG_CLASSES used as the end
237    marker.  */
238 #define IRA_COVER_CLASSES { ALL_REGS, LIM_REG_CLASSES }
239 
240 /* Return the maximum number of consecutive registers
241    needed to represent mode MODE in a register of class CLASS.  */
242 #define CLASS_MAX_NREGS(CLASS, MODE)	\
243   ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
244 
245 /* Define which registers fit in which classes.
246    This is an initializer for a vector of HARD_REG_SET
247    of length N_REG_CLASSES.  */
248 
249 #define REG_CLASS_CONTENTS {{0}, {0xffff}}
250 
251 /* The same information, inverted:
252    Return the class number of the smallest class containing
253    reg number REGNO.  This could be a conditional expression
254    or could index an array.  */
255 
256 #define REGNO_REG_CLASS(REGNO) ALL_REGS
257 
258 /* The class value for index registers, and the one for base regs.  */
259 
260 #define INDEX_REG_CLASS ALL_REGS
261 #define BASE_REG_CLASS ALL_REGS
262 
263 /* Given an rtx X being reloaded into a reg required to be
264    in class CLASS, return the class of reg to actually use.
265    In general this is just CLASS; but on some machines
266    in some cases it is preferable to use a more restrictive class.  */
267 
268 #define PREFERRED_RELOAD_CLASS(X,CLASS)  (CLASS)
269 
270 /* Return the maximum number of consecutive registers
271    needed to represent mode MODE in a register of class CLASS.  */
272 /* On the VAX, this is always the size of MODE in words,
273    since all registers are the same size.  */
274 #define CLASS_MAX_NREGS(CLASS, MODE)	\
275  ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
276 
277 /* Stack layout; function entry, exit and calling.  */
278 
279 /* Define this if pushing a word on the stack
280    makes the stack pointer a smaller address.  */
281 #define STACK_GROWS_DOWNWARD
282 
283 /* Define this to nonzero if the nominal address of the stack frame
284    is at the high-address end of the local variables;
285    that is, each additional local variable allocated
286    goes at a more negative offset in the frame.  */
287 #define FRAME_GROWS_DOWNWARD 1
288 
289 /* Offset within stack frame to start allocating local variables at.
290    If FRAME_GROWS_DOWNWARD, this is the offset to the END of the
291    first local allocated.  Otherwise, it is the offset to the BEGINNING
292    of the first local allocated.  */
293 #define STARTING_FRAME_OFFSET 0
294 
295 /* Given an rtx for the address of a frame,
296    return an rtx for the address of the word in the frame
297    that holds the dynamic chain--the previous frame's address.  */
298 #define DYNAMIC_CHAIN_ADDRESS(FRAME) plus_constant ((FRAME), 12)
299 
300 /* If we generate an insn to push BYTES bytes,
301    this says how many the stack pointer really advances by.
302    On the VAX, -(sp) pushes only the bytes of the operands.  */
303 #define PUSH_ROUNDING(BYTES) (BYTES)
304 
305 /* Offset of first parameter from the argument pointer register value.  */
306 #define FIRST_PARM_OFFSET(FNDECL) 4
307 
308 /* Value is the number of bytes of arguments automatically
309    popped when returning from a subroutine call.
310    FUNDECL is the declaration node of the function (as a tree),
311    FUNTYPE is the data type of the function (as a tree),
312    or for a library call it is an identifier node for the subroutine name.
313    SIZE is the number of bytes of arguments passed on the stack.
314 
315    On the VAX, the RET insn pops a maximum of 255 args for any function.  */
316 
317 #define RETURN_POPS_ARGS(FUNDECL,FUNTYPE,SIZE)	\
318   ((SIZE) > 255 * 4 ? 0 : (SIZE))
319 
320 /* Define how to find the value returned by a function.
321    VALTYPE is the data type of the value (as a tree).
322    If the precise function being called is known, FUNC is its FUNCTION_DECL;
323    otherwise, FUNC is 0.  */
324 
325 /* On the VAX the return value is in R0 regardless.  */
326 
327 #define FUNCTION_VALUE(VALTYPE, FUNC)	\
328   gen_rtx_REG (TYPE_MODE (VALTYPE), 0)
329 
330 /* Define how to find the value returned by a library function
331    assuming the value has mode MODE.  */
332 
333 /* On the VAX the return value is in R0 regardless.  */
334 
335 #define LIBCALL_VALUE(MODE)  gen_rtx_REG (MODE, 0)
336 
337 /* Define this if PCC uses the nonreentrant convention for returning
338    structure and union values.  */
339 
340 #define PCC_STATIC_STRUCT_RETURN
341 
342 /* 1 if N is a possible register number for a function value.
343    On the VAX, R0 is the only register thus used.  */
344 
345 #define FUNCTION_VALUE_REGNO_P(N) ((N) == 0)
346 
347 /* 1 if N is a possible register number for function argument passing.
348    On the VAX, no registers are used in this way.  */
349 
350 #define FUNCTION_ARG_REGNO_P(N) 0
351 
352 /* Define a data type for recording info about an argument list
353    during the scan of that argument list.  This data type should
354    hold all necessary information about the function itself
355    and about the args processed so far, enough to enable macros
356    such as FUNCTION_ARG to determine where the next arg should go.
357 
358    On the VAX, this is a single integer, which is a number of bytes
359    of arguments scanned so far.  */
360 
361 #define CUMULATIVE_ARGS int
362 
363 /* Initialize a variable CUM of type CUMULATIVE_ARGS
364    for a call to a function whose data type is FNTYPE.
365    For a library call, FNTYPE is 0.
366 
367    On the VAX, the offset starts at 0.  */
368 
369 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
370  ((CUM) = 0)
371 
372 /* Update the data in CUM to advance over an argument
373    of mode MODE and data type TYPE.
374    (TYPE is null for libcalls where that information may not be available.)  */
375 
376 #define FUNCTION_ARG_ADVANCE(CUM, MODE, TYPE, NAMED)	\
377   ((CUM) += ((MODE) != BLKmode				\
378 	     ? (GET_MODE_SIZE (MODE) + 3) & ~3		\
379 	     : (int_size_in_bytes (TYPE) + 3) & ~3))
380 
381 /* Define where to put the arguments to a function.
382    Value is zero to push the argument on the stack,
383    or a hard register in which to store the argument.
384 
385    MODE is the argument's machine mode.
386    TYPE is the data type of the argument (as a tree).
387     This is null for libcalls where that information may
388     not be available.
389    CUM is a variable of type CUMULATIVE_ARGS which gives info about
390     the preceding args and about the function being called.
391    NAMED is nonzero if this argument is a named parameter
392     (otherwise it is an extra parameter matching an ellipsis).  */
393 
394 /* On the VAX all args are pushed.  */
395 
396 #define FUNCTION_ARG(CUM, MODE, TYPE, NAMED) 0
397 
398 /* Output assembler code to FILE to increment profiler label # LABELNO
399    for profiling a function entry.  */
400 
401 #define VAX_FUNCTION_PROFILER_NAME "mcount"
402 #define FUNCTION_PROFILER(FILE, LABELNO)			\
403   do								\
404     {								\
405       char label[256];						\
406       ASM_GENERATE_INTERNAL_LABEL (label, "LP", (LABELNO));	\
407       fprintf (FILE, "\tmovab ");				\
408       assemble_name (FILE, label);				\
409       asm_fprintf (FILE, ",%Rr0\n\tjsb %s\n",			\
410 		   VAX_FUNCTION_PROFILER_NAME);			\
411     }								\
412   while (0)
413 
414 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
415    the stack pointer does not matter.  The value is tested only in
416    functions that have frame pointers.
417    No definition is equivalent to always zero.  */
418 
419 #define EXIT_IGNORE_STACK 1
420 
421 /* Store in the variable DEPTH the initial difference between the
422    frame pointer reg contents and the stack pointer reg contents,
423    as of the start of the function body.  This depends on the layout
424    of the fixed parts of the stack frame and on how registers are saved.
425 
426    On the VAX, FRAME_POINTER_REQUIRED is always 1, so the definition of this
427    macro doesn't matter.  But it must be defined.  */
428 
429 #define INITIAL_FRAME_POINTER_OFFSET(DEPTH) (DEPTH) = 0;
430 
431 /* Length in units of the trampoline for entering a nested function.  */
432 
433 #define TRAMPOLINE_SIZE 15
434 
435 /* Byte offset of return address in a stack frame.  The "saved PC" field
436    is in element [4] when treating the frame as an array of longwords.  */
437 
438 #define RETURN_ADDRESS_OFFSET	(4 * UNITS_PER_WORD)	/* 16 */
439 
440 /* A C expression whose value is RTL representing the value of the return
441    address for the frame COUNT steps up from the current frame.
442    FRAMEADDR is already the frame pointer of the COUNT frame, so we
443    can ignore COUNT.  */
444 
445 #define RETURN_ADDR_RTX(COUNT, FRAME)					\
446   ((COUNT == 0)								\
447    ? gen_rtx_MEM (Pmode, plus_constant (FRAME, RETURN_ADDRESS_OFFSET))	\
448    : (rtx) 0)
449 
450 
451 /* Addressing modes, and classification of registers for them.  */
452 
453 #define HAVE_POST_INCREMENT 1
454 
455 #define HAVE_PRE_DECREMENT 1
456 
457 /* Macros to check register numbers against specific register classes.  */
458 
459 /* These assume that REGNO is a hard or pseudo reg number.
460    They give nonzero only if REGNO is a hard reg of the suitable class
461    or a pseudo reg currently allocated to a suitable hard reg.
462    Since they use reg_renumber, they are safe only once reg_renumber
463    has been allocated, which happens in local-alloc.c.  */
464 
465 #define REGNO_OK_FOR_INDEX_P(regno)	\
466   ((regno) < FIRST_PSEUDO_REGISTER || reg_renumber[regno] >= 0)
467 #define REGNO_OK_FOR_BASE_P(regno)	\
468   ((regno) < FIRST_PSEUDO_REGISTER || reg_renumber[regno] >= 0)
469 
470 /* Maximum number of registers that can appear in a valid memory address.  */
471 
472 #define MAX_REGS_PER_ADDRESS 2
473 
474 /* 1 if X is an rtx for a constant that is a valid address.  */
475 
476 #define CONSTANT_ADDRESS_P(X) legitimate_constant_address_p (X)
477 
478 /* Nonzero if the constant value X is a legitimate general operand.
479    It is given that X satisfies CONSTANT_P or is a CONST_DOUBLE.  */
480 
481 #define LEGITIMATE_CONSTANT_P(X) legitimate_constant_p (X)
482 
483 /* The macros REG_OK_FOR..._P assume that the arg is a REG rtx
484    and check its validity for a certain class.
485    We have two alternate definitions for each of them.
486    The usual definition accepts all pseudo regs; the other rejects
487    them unless they have been allocated suitable hard regs.
488    The symbol REG_OK_STRICT causes the latter definition to be used.
489 
490    Most source files want to accept pseudo regs in the hope that
491    they will get allocated to the class that the insn wants them to be in.
492    Source files for reload pass need to be strict.
493    After reload, it makes no difference, since pseudo regs have
494    been eliminated by then.  */
495 
496 #ifndef REG_OK_STRICT
497 
498 /* Nonzero if X is a hard reg that can be used as an index
499    or if it is a pseudo reg.  */
500 #define REG_OK_FOR_INDEX_P(X) 1
501 
502 /* Nonzero if X is a hard reg that can be used as a base reg
503    or if it is a pseudo reg.  */
504 #define REG_OK_FOR_BASE_P(X) 1
505 
506 #else
507 
508 /* Nonzero if X is a hard reg that can be used as an index.  */
509 #define REG_OK_FOR_INDEX_P(X) REGNO_OK_FOR_INDEX_P (REGNO (X))
510 
511 /* Nonzero if X is a hard reg that can be used as a base reg.  */
512 #define REG_OK_FOR_BASE_P(X) REGNO_OK_FOR_BASE_P (REGNO (X))
513 
514 #endif
515 
516 /* Go to LABEL if ADDR (a legitimate address expression)
517    has an effect that depends on the machine mode it is used for.  */
518 #define GO_IF_MODE_DEPENDENT_ADDRESS(ADDR, LABEL) \
519   { if (vax_mode_dependent_address_p (ADDR)) goto LABEL; }
520 
521 /* Specify the machine mode that this machine uses
522    for the index in the tablejump instruction.  */
523 #define CASE_VECTOR_MODE HImode
524 
525 /* Define as C expression which evaluates to nonzero if the tablejump
526    instruction expects the table to contain offsets from the address of the
527    table.
528    Do not define this if the table should contain absolute addresses.  */
529 #define CASE_VECTOR_PC_RELATIVE 1
530 
531 /* Indicate that jump tables go in the text section.  This is
532    necessary when compiling PIC code.  */
533 #define JUMP_TABLES_IN_TEXT_SECTION 1
534 
535 /* Define this as 1 if `char' should by default be signed; else as 0.  */
536 #define DEFAULT_SIGNED_CHAR 1
537 
538 /* This flag, if defined, says the same insns that convert to a signed fixnum
539    also convert validly to an unsigned one.  */
540 #define FIXUNS_TRUNC_LIKE_FIX_TRUNC
541 
542 /* Max number of bytes we can move from memory to memory
543    in one reasonably fast instruction.  */
544 #define MOVE_MAX 8
545 
546 /* If a memory-to-memory move would take MOVE_RATIO or more simple
547    move-instruction pairs, we will do a movmem or libcall instead.  */
548 #define MOVE_RATIO(speed) ((speed) ? 6 : 3)
549 #define CLEAR_RATIO(speed) ((speed) ? 6 : 2)
550 
551 /* Nonzero if access to memory by bytes is slow and undesirable.  */
552 #define SLOW_BYTE_ACCESS 0
553 
554 /* Define if shifts truncate the shift count
555    which implies one can omit a sign-extension or zero-extension
556    of a shift count.  */
557 /* #define SHIFT_COUNT_TRUNCATED */
558 
559 /* Value is 1 if truncating an integer of INPREC bits to OUTPREC bits
560    is done just by pretending it is already truncated.  */
561 #define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC) 1
562 
563 /* Specify the machine mode that pointers have.
564    After generation of rtl, the compiler makes no further distinction
565    between pointers and any other objects of this machine mode.  */
566 #define Pmode SImode
567 
568 /* A function address in a call instruction
569    is a byte address (for indexing purposes)
570    so give the MEM rtx a byte's mode.  */
571 #define FUNCTION_MODE QImode
572 
573 /* Specify the cost of a branch insn; roughly the number of extra insns that
574    should be added to avoid a branch.
575 
576    Branches are extremely cheap on the VAX while the shift insns often
577    used to replace branches can be expensive.  */
578 
579 #define BRANCH_COST(speed_p, predictable_p) 0
580 
581 /* Tell final.c how to eliminate redundant test instructions.  */
582 
583 /* Here we define machine-dependent flags and fields in cc_status
584    (see `conditions.h').  No extra ones are needed for the VAX.  */
585 
586 /* Store in cc_status the expressions
587    that the condition codes will describe
588    after execution of an instruction whose pattern is EXP.
589    Do not alter them if the instruction would not alter the cc's.  */
590 
591 #define NOTICE_UPDATE_CC(EXP, INSN)	\
592   vax_notice_update_cc ((EXP), (INSN))
593 
594 #define OUTPUT_JUMP(NORMAL, FLOAT, NO_OV)	\
595   { if (cc_status.flags & CC_NO_OVERFLOW)	\
596       return NO_OV;				\
597     return NORMAL;				\
598   }
599 
600 /* Control the assembler format that we output.  */
601 
602 /* A C string constant describing how to begin a comment in the target
603    assembler language.  The compiler assumes that the comment will end at
604    the end of the line.  */
605 
606 #define ASM_COMMENT_START "#"
607 
608 /* Output to assembler file text saying following lines
609    may contain character constants, extra white space, comments, etc.  */
610 
611 #define ASM_APP_ON "#APP\n"
612 
613 /* Output to assembler file text saying following lines
614    no longer contain unusual constructs.  */
615 
616 #define ASM_APP_OFF "#NO_APP\n"
617 
618 /* Output before read-only data.  */
619 
620 #define TEXT_SECTION_ASM_OP "\t.text"
621 
622 /* Output before writable data.  */
623 
624 #define DATA_SECTION_ASM_OP "\t.data"
625 
626 /* How to refer to registers in assembler output.
627    This sequence is indexed by compiler's hard-register-number (see above).
628    The register names will be prefixed by REGISTER_PREFIX, if any.  */
629 
630 #define REGISTER_PREFIX ""
631 #define REGISTER_NAMES					\
632   { "r0", "r1",  "r2",  "r3", "r4", "r5", "r6", "r7",	\
633     "r8", "r9", "r10", "r11", "ap", "fp", "sp", "pc", }
634 
635 /* This is BSD, so it wants DBX format.  */
636 
637 #define DBX_DEBUGGING_INFO 1
638 
639 /* Do not break .stabs pseudos into continuations.  */
640 
641 #define DBX_CONTIN_LENGTH 0
642 
643 /* This is the char to use for continuation (in case we need to turn
644    continuation back on).  */
645 
646 #define DBX_CONTIN_CHAR '?'
647 
648 /* Don't use the `xsfoo;' construct in DBX output; this system
649    doesn't support it.  */
650 
651 #define DBX_NO_XREFS
652 
653 /* Output the .stabs for a C `static' variable in the data section.  */
654 #define DBX_STATIC_STAB_DATA_SECTION
655 
656 /* VAX specific: which type character is used for type double?  */
657 
658 #define ASM_DOUBLE_CHAR (TARGET_G_FLOAT ? 'g' : 'd')
659 
660 /* This is how to output a command to make the user-level label named NAME
661    defined for reference from other files.  */
662 
663 /* Globalizing directive for a label.  */
664 #define GLOBAL_ASM_OP ".globl "
665 
666 /* The prefix to add to user-visible assembler symbols.  */
667 
668 #define USER_LABEL_PREFIX "_"
669 
670 /* This is how to store into the string LABEL
671    the symbol_ref name of an internal numbered label where
672    PREFIX is the class of label and NUM is the number within the class.
673    This is suitable for output with `assemble_name'.  */
674 
675 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM)	\
676   sprintf (LABEL, "*%s%ld", PREFIX, (long)(NUM))
677 
678 /* This is how to output an insn to push a register on the stack.
679    It need not be very fast code.  */
680 
681 #define ASM_OUTPUT_REG_PUSH(FILE,REGNO)  \
682   fprintf (FILE, "\tpushl %s\n", reg_names[REGNO])
683 
684 /* This is how to output an insn to pop a register from the stack.
685    It need not be very fast code.  */
686 
687 #define ASM_OUTPUT_REG_POP(FILE,REGNO)					\
688   fprintf (FILE, "\tmovl (%s)+,%s\n", reg_names[STACK_POINTER_REGNUM],	\
689 	   reg_names[REGNO])
690 
691 /* This is how to output an element of a case-vector that is absolute.
692    (The VAX does not use such vectors,
693    but we must define this macro anyway.)  */
694 
695 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE)		\
696   do							\
697     {							\
698       char label[256];					\
699       ASM_GENERATE_INTERNAL_LABEL (label, "L", (VALUE));\
700       fprintf (FILE, "\t.long ");			\
701       assemble_name (FILE, label);			\
702       fprintf (FILE, "\n");				\
703     }							\
704   while (0)
705 
706 /* This is how to output an element of a case-vector that is relative.  */
707 
708 #define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, BODY, VALUE, REL)	\
709   do								\
710     {								\
711       char label[256];						\
712       ASM_GENERATE_INTERNAL_LABEL (label, "L", (VALUE));	\
713       fprintf (FILE, "\t.word ");				\
714       assemble_name (FILE, label);				\
715       ASM_GENERATE_INTERNAL_LABEL (label, "L", (REL));		\
716       fprintf (FILE, "-");					\
717       assemble_name (FILE, label);				\
718       fprintf (FILE, "\n");					\
719     }								\
720   while (0)
721 
722 /* This is how to output an assembler line
723    that says to advance the location counter
724    to a multiple of 2**LOG bytes.  */
725 
726 #define ASM_OUTPUT_ALIGN(FILE,LOG)  \
727   fprintf (FILE, "\t.align %d\n", (LOG))
728 
729 /* This is how to output an assembler line
730    that says to advance the location counter by SIZE bytes.  */
731 
732 #define ASM_OUTPUT_SKIP(FILE,SIZE)  \
733   fprintf (FILE, "\t.space %u\n", (int)(SIZE))
734 
735 /* This says how to output an assembler line
736    to define a global common symbol.  */
737 
738 #define ASM_OUTPUT_COMMON(FILE, NAME, SIZE, ROUNDED)	\
739   ( fputs (".comm ", (FILE)),				\
740     assemble_name ((FILE), (NAME)),			\
741     fprintf ((FILE), ",%u\n", (int)(ROUNDED)))
742 
743 /* This says how to output an assembler line
744    to define a local common symbol.  */
745 
746 #define ASM_OUTPUT_LOCAL(FILE, NAME, SIZE, ROUNDED)	\
747   ( fputs (".lcomm ", (FILE)),				\
748     assemble_name ((FILE), (NAME)),			\
749     fprintf ((FILE), ",%u\n", (int)(ROUNDED)))
750 
751 /* Print an instruction operand X on file FILE.
752    CODE is the code from the %-spec that requested printing this operand;
753    if `%z3' was used to print operand 3, then CODE is 'z'.
754 
755 VAX operand formatting codes:
756 
757  letter	   print
758    c	direct branch condition
759    C	reverse branch condition
760    D	64-bit immediate operand
761    B	the low 8 bits of the complement of a constant operand
762    H	the low 16 bits of the complement of a constant operand
763    M	a mask for the N highest bits of a word
764    N	the complement of a constant integer operand
765    P	constant operand plus 1
766    R	32 - constant operand
767    b	the low 8 bits of a negated constant operand
768    h	the low 16 bits of a negated constant operand
769    #	'd' or 'g' depending on whether dfloat or gfloat is used
770    |	register prefix  */
771 
772 /* The purpose of D is to get around a quirk or bug in VAX assembler
773    whereby -1 in a 64-bit immediate operand means 0x00000000ffffffff,
774    which is not a 64-bit minus one.  As a workaround, we output negative
775    values in hex.  */
776 #if HOST_BITS_PER_WIDE_INT == 64
777 #  define NEG_HWI_PRINT_HEX16 HOST_WIDE_INT_PRINT_HEX
778 #else
779 #  define NEG_HWI_PRINT_HEX16 "0xffffffff%08lx"
780 #endif
781 
782 #define PRINT_OPERAND_PUNCT_VALID_P(CODE)  \
783   ((CODE) == '#' || (CODE) == '|')
784 
785 #define PRINT_OPERAND(FILE, X, CODE)  \
786   print_operand (FILE, X, CODE)
787 
788 /* Print a memory operand whose address is X, on file FILE.
789    This uses a function in output-vax.c.  */
790 
791 #define PRINT_OPERAND_ADDRESS(FILE, ADDR)  \
792   print_operand_address (FILE, ADDR)
793 
794 /* This is a blatent lie.  However, it's good enough, since we don't
795    actually have any code whatsoever for which this isn't overridden
796    by the proper FDE definition.  */
797 #define INCOMING_RETURN_ADDR_RTX gen_rtx_REG (Pmode, PC_REGNUM)
798 
799