1 /* Definitions of target machine for GNU compiler, for the pdp-11
2 Copyright (C) 1994-2017 Free Software Foundation, Inc.
3 Contributed by Michael K. Gschwind (mike@vlsivie.tuwien.ac.at).
5 This file is part of GCC.
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)
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.
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/>. */
21 #define CONSTANT_POOL_BEFORE_FUNCTION 0
23 /* check whether load_fpu_reg or not */
24 #define LOAD_FPU_REG_P(x) ((x) >= AC0_REGNUM && (x) <= AC3_REGNUM)
25 #define NO_LOAD_FPU_REG_P(x) ((x) == AC4_REGNUM || (x) == AC5_REGNUM)
26 #define FPU_REG_P(x) (LOAD_FPU_REG_P(x) || NO_LOAD_FPU_REG_P(x))
27 #define CPU_REG_P(x) ((x) <= PC_REGNUM)
29 /* Names to predefine in the preprocessor for this target machine. */
31 #define TARGET_CPU_CPP_BUILTINS() \
34 builtin_define_std ("pdp11"); \
39 /* Generate DBX debugging information. */
41 #define DBX_DEBUGGING_INFO
43 #define TARGET_40_PLUS (TARGET_40 || TARGET_45)
44 #define TARGET_10 (! TARGET_40_PLUS)
46 #define TARGET_UNIX_ASM_DEFAULT 0
48 #define ASSEMBLER_DIALECT (TARGET_UNIX_ASM ? 1 : 0)
53 #define SHORT_TYPE_SIZE 16
54 #define INT_TYPE_SIZE (TARGET_INT16 ? 16 : 32)
55 #define LONG_TYPE_SIZE 32
56 #define LONG_LONG_TYPE_SIZE 64
58 /* if we set FLOAT_TYPE_SIZE to 32, we could have the benefit
59 of saving core for huge arrays - the definitions are
60 already in md - but floats can never reside in
61 an FPU register - we keep the FPU in double float mode
63 #define FLOAT_TYPE_SIZE (TARGET_FLOAT32 ? 32 : 64)
64 #define DOUBLE_TYPE_SIZE 64
65 #define LONG_DOUBLE_TYPE_SIZE 64
67 /* machine types from ansi */
68 #define SIZE_TYPE "unsigned int" /* definition of size_t */
69 #define WCHAR_TYPE "int" /* or long int???? */
70 #define WCHAR_TYPE_SIZE 16
72 #define PTRDIFF_TYPE "int"
74 /* target machine storage layout */
76 /* Define this if most significant bit is lowest numbered
77 in instructions that operate on numbered bit-fields. */
78 #define BITS_BIG_ENDIAN 0
80 /* Define this if most significant byte of a word is the lowest numbered. */
81 #define BYTES_BIG_ENDIAN 0
83 /* Define this if most significant word of a multiword number is first. */
84 #define WORDS_BIG_ENDIAN 1
86 /* Define that floats are in VAX order, not high word first as for ints. */
87 #define FLOAT_WORDS_BIG_ENDIAN 0
89 /* Width of a word, in units (bytes).
91 UNITS OR BYTES - seems like units */
92 #define UNITS_PER_WORD 2
94 /* This machine doesn't use IEEE floats. */
95 /* Because the pdp11 (at least Unix) convention for 32-bit ints is
96 big endian, opposite for what you need for float, the vax float
97 conversion routines aren't actually used directly. But the underlying
98 format is indeed the vax/pdp11 float format. */
99 extern const struct real_format pdp11_f_format
;
100 extern const struct real_format pdp11_d_format
;
102 /* Maximum sized of reasonable data type
103 DImode or Dfmode ...*/
104 #define MAX_FIXED_MODE_SIZE 64
106 /* Allocation boundary (in *bits*) for storing pointers in memory. */
107 #define POINTER_BOUNDARY 16
109 /* Allocation boundary (in *bits*) for storing arguments in argument list. */
110 #define PARM_BOUNDARY 16
112 /* Boundary (in *bits*) on which stack pointer should be aligned. */
113 #define STACK_BOUNDARY 16
115 /* Allocation boundary (in *bits*) for the code of a function. */
116 #define FUNCTION_BOUNDARY 16
118 /* Alignment of field after `int : 0' in a structure. */
119 #define EMPTY_FIELD_BOUNDARY 16
121 /* No data type wants to be aligned rounder than this. */
122 #define BIGGEST_ALIGNMENT 16
124 /* Define this if move instructions will actually fail to work
125 when given unaligned data. */
126 #define STRICT_ALIGNMENT 1
128 /* Standard register usage. */
130 /* Number of actual hardware registers.
131 The hardware registers are assigned numbers for the compiler
132 from 0 to just below FIRST_PSEUDO_REGISTER.
133 All registers that the compiler knows about must be given numbers,
134 even those that are not normally considered general registers.
136 we have 8 integer registers, plus 6 float
137 (don't use scratch float !) */
139 /* 1 for registers that have pervasive standard uses
140 and are not available for the register allocator.
142 On the pdp, these are:
145 reg 5 = fp; not necessarily!
148 #define FIXED_REGISTERS \
149 {0, 0, 0, 0, 0, 0, 1, 1, \
150 0, 0, 0, 0, 0, 0, 1, 1 }
154 /* 1 for registers not available across function calls.
155 These must include the FIXED_REGISTERS and also any
156 registers that can be used without being saved.
157 The latter must include the registers where values are returned
158 and the register where structure-value addresses are passed.
159 Aside from that, you can include as many other registers as you like. */
161 /* don't know about fp */
162 #define CALL_USED_REGISTERS \
163 {1, 1, 0, 0, 0, 0, 1, 1, \
164 0, 0, 0, 0, 0, 0, 1, 1 }
167 /* Specify the registers used for certain standard purposes.
168 The values of these macros are register numbers. */
170 /* Register in which static-chain is passed to a function. */
171 /* ??? - i don't want to give up a reg for this! */
172 #define STATIC_CHAIN_REGNUM 4
174 /* Define the classes of registers for register constraints in the
175 machine description. Also define ranges of constants.
177 One of the classes must always be named ALL_REGS and include all hard regs.
178 If there is more than one class, another class must be named NO_REGS
179 and contain no registers.
181 The name GENERAL_REGS must be the name of a class (or an alias for
182 another name such as ALL_REGS). This is the class of registers
183 that is allowed by "g" or "r" in a register constraint.
184 Also, registers outside this class are allocated only when
185 instructions express preferences for them.
187 The classes must be numbered in nondecreasing order; that is,
188 a larger-numbered class must never be contained completely
189 in a smaller-numbered class.
191 For any two classes, it is very desirable that there be another
192 class that represents their union. */
194 /* The pdp has a couple of classes:
196 MUL_REGS are used for odd numbered regs, to use in 16-bit multiplication
197 (even numbered do 32-bit multiply)
198 LMUL_REGS long multiply registers (even numbered regs )
199 (don't need them, all 32-bit regs are even numbered!)
200 GENERAL_REGS is all cpu
201 LOAD_FPU_REGS is the first four cpu regs, they are easier to load
202 NO_LOAD_FPU_REGS is ac4 and ac5, currently - difficult to load them
203 FPU_REGS is all fpu regs
206 enum reg_class
{ NO_REGS
, MUL_REGS
, GENERAL_REGS
, LOAD_FPU_REGS
, NO_LOAD_FPU_REGS
, FPU_REGS
, ALL_REGS
, LIM_REG_CLASSES
};
208 #define N_REG_CLASSES (int) LIM_REG_CLASSES
210 /* have to allow this till cmpsi/tstsi are fixed in a better way !! */
211 #define TARGET_SMALL_REGISTER_CLASSES_FOR_MODE_P hook_bool_mode_true
213 /* Since GENERAL_REGS is the same class as ALL_REGS,
214 don't give it a different class number; just make it an alias. */
216 /* #define GENERAL_REGS ALL_REGS */
218 /* Give names of register classes as strings for dump file. */
220 #define REG_CLASS_NAMES {"NO_REGS", "MUL_REGS", "GENERAL_REGS", "LOAD_FPU_REGS", "NO_LOAD_FPU_REGS", "FPU_REGS", "ALL_REGS" }
222 /* Define which registers fit in which classes.
223 This is an initializer for a vector of HARD_REG_SET
224 of length N_REG_CLASSES. */
226 #define REG_CLASS_CONTENTS {{0}, {0x00aa}, {0xc0ff}, {0x0f00}, {0x3000}, {0x3f00}, {0xffff}}
228 /* The same information, inverted:
229 Return the class number of the smallest class containing
230 reg number REGNO. This could be a conditional expression
231 or could index an array. */
233 #define REGNO_REG_CLASS(REGNO) pdp11_regno_reg_class (REGNO)
235 /* The class value for index registers, and the one for base regs. */
236 #define INDEX_REG_CLASS GENERAL_REGS
237 #define BASE_REG_CLASS GENERAL_REGS
239 /* Return the maximum number of consecutive registers
240 needed to represent mode MODE in a register of class CLASS. */
241 #define CLASS_MAX_NREGS(CLASS, MODE) \
242 ((CLASS == GENERAL_REGS || CLASS == MUL_REGS)? \
243 ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD): \
247 #define CANNOT_CHANGE_MODE_CLASS(FROM, TO, CLASS) \
248 pdp11_cannot_change_mode_class (FROM, TO, CLASS)
250 /* Stack layout; function entry, exit and calling. */
252 /* Define this if pushing a word on the stack
253 makes the stack pointer a smaller address. */
254 #define STACK_GROWS_DOWNWARD 1
256 /* Define this to nonzero if the nominal address of the stack frame
257 is at the high-address end of the local variables;
258 that is, each additional local variable allocated
259 goes at a more negative offset in the frame.
261 #define FRAME_GROWS_DOWNWARD 1
263 /* Offset within stack frame to start allocating local variables at.
264 If FRAME_GROWS_DOWNWARD, this is the offset to the END of the
265 first local allocated. Otherwise, it is the offset to the BEGINNING
266 of the first local allocated. */
267 #define STARTING_FRAME_OFFSET 0
269 /* If we generate an insn to push BYTES bytes,
270 this says how many the stack pointer really advances by.
271 On the pdp11, the stack is on an even boundary */
272 #define PUSH_ROUNDING(BYTES) ((BYTES + 1) & ~1)
274 /* current_first_parm_offset stores the # of registers pushed on the
276 extern int current_first_parm_offset
;
278 /* Offset of first parameter from the argument pointer register value. */
279 #define FIRST_PARM_OFFSET(FNDECL) 0
281 /* Define how to find the value returned by a function.
282 VALTYPE is the data type of the value (as a tree).
283 If the precise function being called is known, FUNC is its FUNCTION_DECL;
284 otherwise, FUNC is 0. */
285 #define BASE_RETURN_VALUE_REG(MODE) \
286 (FLOAT_MODE_P (MODE) ? AC0_REGNUM : RETVAL_REGNUM)
288 /* 1 if N is a possible register number for function argument passing.
291 #define FUNCTION_ARG_REGNO_P(N) 0
293 /* Define a data type for recording info about an argument list
294 during the scan of that argument list. This data type should
295 hold all necessary information about the function itself
296 and about the args processed so far, enough to enable macros
297 such as FUNCTION_ARG to determine where the next arg should go.
301 #define CUMULATIVE_ARGS int
303 /* Initialize a variable CUM of type CUMULATIVE_ARGS
304 for a call to a function whose data type is FNTYPE.
305 For a library call, FNTYPE is 0.
307 ...., the offset normally starts at 0, but starts at 1 word
308 when the function gets a structure-value-address as an
309 invisible first argument. */
311 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, INDIRECT, N_NAMED_ARGS) \
314 /* Output assembler code to FILE to increment profiler label # LABELNO
315 for profiling a function entry. */
317 #define FUNCTION_PROFILER(FILE, LABELNO) \
320 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
321 the stack pointer does not matter. The value is tested only in
322 functions that have frame pointers.
323 No definition is equivalent to always zero. */
325 extern int may_call_alloca
;
327 #define EXIT_IGNORE_STACK 1
329 /* Definitions for register eliminations.
331 This is an array of structures. Each structure initializes one pair
332 of eliminable registers. The "from" register number is given first,
333 followed by "to". Eliminations of the same "from" register are listed
334 in order of preference.
336 There are two registers that can always be eliminated on the pdp11.
337 The frame pointer and the arg pointer can be replaced by either the
338 hard frame pointer or to the stack pointer, depending upon the
339 circumstances. The hard frame pointer is not used before reload and
340 so it is not eligible for elimination. */
342 #define ELIMINABLE_REGS \
343 {{ ARG_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
344 { ARG_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}, \
345 { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
346 { FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}} \
348 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
349 ((OFFSET) = pdp11_initial_elimination_offset ((FROM), (TO)))
352 /* Addressing modes, and classification of registers for them. */
354 #define HAVE_POST_INCREMENT 1
356 #define HAVE_PRE_DECREMENT 1
358 /* Macros to check register numbers against specific register classes. */
360 /* These assume that REGNO is a hard or pseudo reg number.
361 They give nonzero only if REGNO is a hard reg of the suitable class
362 or a pseudo reg currently allocated to a suitable hard reg.
363 Since they use reg_renumber, they are safe only once reg_renumber
364 has been allocated, which happens in reginfo.c during register
367 #define REGNO_OK_FOR_BASE_P(REGNO) \
368 ((REGNO) <= PC_REGNUM || (unsigned) reg_renumber[REGNO] <= PC_REGNUM || \
369 (REGNO) == ARG_POINTER_REGNUM || (REGNO) == FRAME_POINTER_REGNUM)
371 #define REGNO_OK_FOR_INDEX_P(REGNO) REGNO_OK_FOR_BASE_P (REGNO)
373 /* Now macros that check whether X is a register and also,
374 strictly, whether it is in a specified class.
379 /* Maximum number of registers that can appear in a valid memory address. */
381 #define MAX_REGS_PER_ADDRESS 1
383 /* The macros REG_OK_FOR..._P assume that the arg is a REG rtx
384 and check its validity for a certain class.
385 We have two alternate definitions for each of them.
386 The usual definition accepts all pseudo regs; the other rejects
387 them unless they have been allocated suitable hard regs.
388 The symbol REG_OK_STRICT causes the latter definition to be used.
390 Most source files want to accept pseudo regs in the hope that
391 they will get allocated to the class that the insn wants them to be in.
392 Source files for reload pass need to be strict.
393 After reload, it makes no difference, since pseudo regs have
394 been eliminated by then. */
396 #ifndef REG_OK_STRICT
398 /* Nonzero if X is a hard reg that can be used as an index
399 or if it is a pseudo reg. */
400 #define REG_OK_FOR_INDEX_P(X) (1)
401 /* Nonzero if X is a hard reg that can be used as a base reg
402 or if it is a pseudo reg. */
403 #define REG_OK_FOR_BASE_P(X) (1)
407 /* Nonzero if X is a hard reg that can be used as an index. */
408 #define REG_OK_FOR_INDEX_P(X) REGNO_OK_FOR_INDEX_P (REGNO (X))
409 /* Nonzero if X is a hard reg that can be used as a base reg. */
410 #define REG_OK_FOR_BASE_P(X) REGNO_OK_FOR_BASE_P (REGNO (X))
414 /* Specify the machine mode that this machine uses
415 for the index in the tablejump instruction. */
416 #define CASE_VECTOR_MODE HImode
418 /* Define this if a raw index is all that is needed for a
420 #define CASE_TAKES_INDEX_RAW
422 /* Define this as 1 if `char' should by default be signed; else as 0. */
423 #define DEFAULT_SIGNED_CHAR 1
425 /* Max number of bytes we can move from memory to memory
426 in one reasonably fast instruction.
431 /* Nonzero if access to memory by byte is slow and undesirable. -
433 #define SLOW_BYTE_ACCESS 0
435 /* Do not break .stabs pseudos into continuations. */
436 #define DBX_CONTIN_LENGTH 0
438 /* Value is 1 if truncating an integer of INPREC bits to OUTPREC bits
439 is done just by pretending it is already truncated. */
440 #define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC) 1
442 /* Give a comparison code (EQ, NE etc) and the first operand of a COMPARE,
443 return the mode to be used for the comparison. For floating-point, CCFPmode
446 #define SELECT_CC_MODE(OP,X,Y) \
447 (GET_MODE_CLASS(GET_MODE(X)) == MODE_FLOAT? CCFPmode : CCmode)
449 /* Specify the machine mode that pointers have.
450 After generation of rtl, the compiler makes no further distinction
451 between pointers and any other objects of this machine mode. */
454 /* A function address in a call instruction
455 is a word address (for indexing purposes)
456 so give the MEM rtx a word's mode. */
457 #define FUNCTION_MODE HImode
459 /* Define this if addresses of constant functions
460 shouldn't be put through pseudo regs where they can be cse'd.
461 Desirable on machines where ordinary constants are expensive
462 but a CALL with constant address is cheap. */
463 /* #define NO_FUNCTION_CSE */
466 /* Tell emit-rtl.c how to initialize special values on a per-function base. */
467 extern rtx cc0_reg_rtx
;
469 #define CC_STATUS_MDEP rtx
471 #define CC_STATUS_MDEP_INIT (cc_status.mdep = 0)
473 /* Tell final.c how to eliminate redundant test instructions. */
475 /* Here we define machine-dependent flags and fields in cc_status
476 (see `conditions.h'). */
478 #define CC_IN_FPU 04000
480 /* Do UPDATE_CC if EXP is a set, used in
483 floats only do compare correctly, else nullify ...
488 /* Store in cc_status the expressions
489 that the condition codes will describe
490 after execution of an instruction whose pattern is EXP.
491 Do not alter them if the instruction would not alter the cc's. */
493 #define NOTICE_UPDATE_CC(EXP, INSN) \
494 { if (GET_CODE (EXP) == SET) \
496 notice_update_cc_on_set(EXP, INSN); \
498 else if (GET_CODE (EXP) == PARALLEL \
499 && GET_CODE (XVECEXP (EXP, 0, 0)) == SET) \
501 notice_update_cc_on_set(XVECEXP (EXP, 0, 0), INSN); \
503 else if (GET_CODE (EXP) == CALL) \
504 { /* all bets are off */ CC_STATUS_INIT; } \
505 if (cc_status.value1 && GET_CODE (cc_status.value1) == REG \
506 && cc_status.value2 \
507 && reg_overlap_mentioned_p (cc_status.value1, cc_status.value2)) \
509 printf ("here!\n"); \
510 cc_status.value2 = 0; \
514 /* Control the assembler format that we output. */
516 /* Output to assembler file text saying following lines
517 may contain character constants, extra white space, comments, etc. */
519 #define ASM_APP_ON ""
521 /* Output to assembler file text saying following lines
522 no longer contain unusual constructs. */
524 #define ASM_APP_OFF ""
526 /* Output before read-only data. */
528 #define TEXT_SECTION_ASM_OP "\t.text\n"
530 /* Output before writable data. */
532 #define DATA_SECTION_ASM_OP "\t.data\n"
534 /* How to refer to registers in assembler output.
535 This sequence is indexed by compiler's hard-register-number (see above). */
537 #define REGISTER_NAMES \
538 {"r0", "r1", "r2", "r3", "r4", "r5", "sp", "pc", \
539 "ac0", "ac1", "ac2", "ac3", "ac4", "ac5", "fp", "ap" }
541 /* Globalizing directive for a label. */
542 #define GLOBAL_ASM_OP "\t.globl "
544 /* The prefix to add to user-visible assembler symbols. */
546 #define USER_LABEL_PREFIX "_"
548 /* This is how to store into the string LABEL
549 the symbol_ref name of an internal numbered label where
550 PREFIX is the class of label and NUM is the number within the class.
551 This is suitable for output with `assemble_name'. */
553 #define ASM_GENERATE_INTERNAL_LABEL(LABEL,PREFIX,NUM) \
554 sprintf (LABEL, "*%s_%lu", PREFIX, (unsigned long)(NUM))
556 #define ASM_OUTPUT_ASCII(FILE, P, SIZE) \
557 output_ascii (FILE, P, SIZE)
559 /* This is how to output an element of a case-vector that is absolute. */
561 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE) \
562 fprintf (FILE, "\t%sL_%d\n", TARGET_UNIX_ASM ? "" : ".word ", VALUE)
564 /* This is how to output an element of a case-vector that is relative.
565 Don't define this if it is not supported. */
567 /* #define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, VALUE, REL) */
569 /* This is how to output an assembler line
570 that says to advance the location counter
571 to a multiple of 2**LOG bytes.
576 #define ASM_OUTPUT_ALIGN(FILE,LOG) \
582 fprintf (FILE, "\t.even\n"); \
585 gcc_unreachable (); \
588 #define ASM_OUTPUT_SKIP(FILE,SIZE) \
589 fprintf (FILE, "\t.=.+ %#ho\n", (unsigned short)(SIZE))
591 /* This says how to output an assembler line
592 to define a global common symbol. */
594 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN) \
595 pdp11_asm_output_var (FILE, NAME, SIZE, ALIGN, true)
598 /* This says how to output an assembler line
599 to define a local common symbol. */
601 #define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN) \
602 pdp11_asm_output_var (FILE, NAME, SIZE, ALIGN, false)
604 /* Print a memory address as an operand to reference that memory location. */
606 #define PRINT_OPERAND_ADDRESS(FILE, ADDR) \
607 print_operand_address (FILE, ADDR)
609 #define ASM_OUTPUT_REG_PUSH(FILE,REGNO) \
611 fprintf (FILE, "\tmov %s, -(sp)\n", reg_names[REGNO]) \
614 #define ASM_OUTPUT_REG_POP(FILE,REGNO) \
616 fprintf (FILE, "\tmov (sp)+, %s\n", reg_names[REGNO]) \
619 #define TRAMPOLINE_SIZE 8
620 #define TRAMPOLINE_ALIGNMENT 16
622 /* there is no point in avoiding branches on a pdp,
623 since branches are really cheap - I just want to find out
624 how much difference the BRANCH_COST macro makes in code */
625 #define BRANCH_COST(speed_p, predictable_p) pdp11_branch_cost ()
627 #define COMPARE_FLAG_MODE HImode
629 #define TARGET_HAVE_NAMED_SECTIONS false
631 /* pdp11-unknown-aout target has no support of C99 runtime */
632 #undef TARGET_LIBC_HAS_FUNCTION
633 #define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function