Turn FUNCTION_ARG_PADDING into a target hook
[official-gcc.git] / gcc / config / nios2 / nios2.h
blob3e26cb67247038801ec3a184878a9b479c2a8ef5
1 /* Definitions of target machine for Altera Nios II.
2 Copyright (C) 2012-2017 Free Software Foundation, Inc.
3 Contributed by Jonah Graham (jgraham@altera.com),
4 Will Reece (wreece@altera.com), and Jeff DaSilva (jdasilva@altera.com).
5 Contributed by Mentor Graphics, Inc.
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify it
10 under the terms of the GNU General Public License as published
11 by the Free Software Foundation; either version 3, or (at your
12 option) any later version.
14 GCC is distributed in the hope that it will be useful, but WITHOUT
15 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
16 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
17 License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
23 #ifndef GCC_NIOS2_H
24 #define GCC_NIOS2_H
26 /* Indicate R2 ISA level support. */
27 #define TARGET_ARCH_R2 (nios2_arch_option == ARCH_R2)
29 /* FPU insn codes declared here. */
30 #include "config/nios2/nios2-opts.h"
32 /* Define built-in preprocessor macros. */
33 #define TARGET_CPU_CPP_BUILTINS() \
34 do \
35 { \
36 builtin_define_std ("NIOS2"); \
37 builtin_define_std ("nios2"); \
38 if (TARGET_BIG_ENDIAN) \
39 builtin_define_std ("nios2_big_endian"); \
40 else \
41 builtin_define_std ("nios2_little_endian"); \
42 builtin_define_with_int_value ( \
43 "__nios2_arch__", (int) nios2_arch_option); \
44 } \
45 while (0)
47 /* We're little endian, unless otherwise specified by defining
48 BIG_ENDIAN_FLAG. */
49 #ifndef TARGET_ENDIAN_DEFAULT
50 # define TARGET_ENDIAN_DEFAULT 0
51 #endif
53 /* Default target_flags if no switches specified. */
54 #ifndef TARGET_DEFAULT
55 # define TARGET_DEFAULT (MASK_HAS_MUL | TARGET_ENDIAN_DEFAULT)
56 #endif
58 #define OPTION_DEFAULT_SPECS \
59 {"arch", "%{!march=*:%{!mcpu=*:-march=%(VALUE)}}" }
61 #define CC1_SPEC "%{G*}"
63 #if TARGET_ENDIAN_DEFAULT == 0
64 # define ASM_SPEC "%{!meb:-EL} %{meb:-EB} %{march=*:-march=%*}"
65 # define LINK_SPEC_ENDIAN "%{!meb:-EL} %{meb:-EB}"
66 # define MULTILIB_DEFAULTS { "EL" }
67 #else
68 # define ASM_SPEC "%{!mel:-EB} %{mel:-EL} %{march=*:-march=%*}"
69 # define LINK_SPEC_ENDIAN "%{!mel:-EB} %{mel:-EL}"
70 # define MULTILIB_DEFAULTS { "EB" }
71 #endif
73 #define LINK_SPEC LINK_SPEC_ENDIAN \
74 " %{shared:-shared} \
75 %{static:-Bstatic}"
78 /* Storage layout. */
80 #define DEFAULT_SIGNED_CHAR 1
81 #define BITS_BIG_ENDIAN 0
82 #define BYTES_BIG_ENDIAN (TARGET_BIG_ENDIAN != 0)
83 #define WORDS_BIG_ENDIAN (TARGET_BIG_ENDIAN != 0)
84 #define BITS_PER_WORD 32
85 #define UNITS_PER_WORD 4
86 #define POINTER_SIZE 32
87 #define BIGGEST_ALIGNMENT 32
88 #define STRICT_ALIGNMENT 1
89 #define FUNCTION_BOUNDARY 32
90 #define PARM_BOUNDARY 32
91 #define STACK_BOUNDARY 32
92 #define PREFERRED_STACK_BOUNDARY 32
93 #define MAX_FIXED_MODE_SIZE 64
95 #define CONSTANT_ALIGNMENT(EXP, ALIGN) \
96 ((TREE_CODE (EXP) == STRING_CST) \
97 && (ALIGN) < BITS_PER_WORD ? BITS_PER_WORD : (ALIGN))
99 #define LABEL_ALIGN(LABEL) nios2_label_align (LABEL)
101 /* Layout of source language data types. */
103 #define INT_TYPE_SIZE 32
104 #define SHORT_TYPE_SIZE 16
105 #define LONG_TYPE_SIZE 32
106 #define LONG_LONG_TYPE_SIZE 64
107 #define FLOAT_TYPE_SIZE 32
108 #define DOUBLE_TYPE_SIZE 64
109 #define LONG_DOUBLE_TYPE_SIZE DOUBLE_TYPE_SIZE
111 #undef SIZE_TYPE
112 #define SIZE_TYPE "unsigned int"
114 #undef PTRDIFF_TYPE
115 #define PTRDIFF_TYPE "int"
118 /* Basic characteristics of Nios II registers:
120 Regno Name
121 0 r0 zero always zero
122 1 r1 at Assembler Temporary
123 2-3 r2-r3 Return Location
124 4-7 r4-r7 Register Arguments
125 8-15 r8-r15 Caller Saved Registers
126 16-22 r16-r22 Callee Saved Registers
127 22 r22 Global Offset Table pointer (Linux ABI only)
128 23 r23 Thread pointer (Linux ABI only)
129 24 r24 et Exception Temporary
130 25 r25 bt Breakpoint Temporary
131 26 r26 gp Global Pointer
132 27 r27 sp Stack Pointer
133 28 r28 fp Frame Pointer
134 29 r29 ea Exception Return Address
135 30 r30 ba Breakpoint Return Address
136 31 r31 ra Return Address
138 32 ctl0 status
139 33 ctl1 estatus STATUS saved by exception
140 34 ctl2 bstatus STATUS saved by break
141 35 ctl3 ipri Interrupt Priority Mask
142 36 ctl4 ecause Exception Cause
144 37 pc Not an actual register
146 38 fake_fp Fake Frame Pointer (always eliminated)
147 39 fake_ap Fake Argument Pointer (always eliminated)
148 40 First Pseudo Register
150 In addition, r12 is used as the static chain register and r13, r14, and r15
151 are clobbered by PLT code sequences.
153 The definitions for all the hard register numbers are located in nios2.md.
156 #define FIXED_REGISTERS \
158 /* +0 1 2 3 4 5 6 7 8 9 */ \
159 /* 0 */ 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, \
160 /* 10 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
161 /* 20 */ 0, 0, TARGET_LINUX_ABI, TARGET_LINUX_ABI, 1, 1, 1, 1, 0, 1, \
162 /* 30 */ 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, \
165 /* Call used == caller saved + fixed regs + args + ret vals. */
166 #define CALL_USED_REGISTERS \
168 /* +0 1 2 3 4 5 6 7 8 9 */ \
169 /* 0 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
170 /* 10 */ 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, \
171 /* 20 */ 0, 0, TARGET_LINUX_ABI, TARGET_LINUX_ABI, 1, 1, 1, 1, 0, 1, \
172 /* 30 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, \
175 #define HARD_REGNO_NREGS(REGNO, MODE) \
176 ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
178 /* Order in which to allocate registers. Each register must be
179 listed once. This is the default ordering for R1 and non-CDX R2
180 code. For CDX, we overwrite this in ADJUST_REG_ALLOC_ORDER. */
181 #define REG_ALLOC_ORDER \
182 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, \
183 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, \
184 37, 38, 39 }
186 #define ADJUST_REG_ALLOC_ORDER nios2_adjust_reg_alloc_order ()
188 /* Caller-save costs can be less emphasized under R2 CDX, where we can
189 use push.n/pop.n. */
190 #define HONOR_REG_ALLOC_ORDER (TARGET_HAS_CDX)
192 /* Register Classes. */
194 enum reg_class
196 NO_REGS,
197 SIB_REGS,
198 IJMP_REGS,
199 GP_REGS,
200 ALL_REGS,
201 LIM_REG_CLASSES
204 #define N_REG_CLASSES (int) LIM_REG_CLASSES
206 #define REG_CLASS_NAMES \
207 { "NO_REGS", \
208 "SIB_REGS", \
209 "IJMP_REGS", \
210 "GP_REGS", \
211 "ALL_REGS" }
213 #define GENERAL_REGS ALL_REGS
215 #define REG_CLASS_CONTENTS \
217 /* NO_REGS */ { 0, 0}, \
218 /* SIB_REGS */ { 0xfe0c, 0}, \
219 /* IJMP_REGS */ { 0x7fffffff, 0}, \
220 /* GP_REGS */ {~0, 0}, \
221 /* ALL_REGS */ {~0,~0} \
225 #define GP_REG_P(REGNO) ((unsigned)(REGNO) <= LAST_GP_REG)
226 #define REGNO_REG_CLASS(REGNO) (GP_REG_P (REGNO) ? GP_REGS : ALL_REGS)
227 #define CLASS_MAX_NREGS(CLASS, MODE) \
228 ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
230 #define CDX_REG_P(REGNO) \
231 ((REGNO) == 16 || (REGNO) == 17 || (2 <= (REGNO) && (REGNO) <= 7))
233 /* Tests for various kinds of constants used in the Nios II port. */
235 #define SMALL_INT(X) ((unsigned HOST_WIDE_INT)(X) + 0x8000 < 0x10000)
236 #define SMALL_INT12(X) ((unsigned HOST_WIDE_INT)(X) + 0x800 < 0x1000)
237 #define SMALL_INT_UNSIGNED(X) ((X) >= 0 && (X) < 0x10000)
238 #define UPPER16_INT(X) (((X) & 0xffff) == 0)
239 #define SHIFT_INT(X) ((X) >= 0 && (X) <= 31)
240 #define RDWRCTL_INT(X) ((X) >= 0 && (X) <= 31)
241 #define CUSTOM_INSN_OPCODE(X) ((X) >= 0 && (X) <= 255)
242 #define ANDCLEAR_INT(X) \
243 (((X) & 0xffff) == 0xffff || (((X) >> 16) & 0xffff) == 0xffff)
245 /* Say that the epilogue uses the return address register. Note that
246 in the case of sibcalls, the values "used by the epilogue" are
247 considered live at the start of the called function. */
248 #define EPILOGUE_USES(REGNO) (epilogue_completed && (REGNO) == RA_REGNO)
250 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
251 the stack pointer does not matter. The value is tested only in
252 functions that have frame pointers.
253 No definition is equivalent to always zero. */
255 #define EXIT_IGNORE_STACK 1
257 /* Trampolines use a 5-instruction sequence. */
258 #define TRAMPOLINE_SIZE 20
260 /* Stack layout. */
261 #define STACK_GROWS_DOWNWARD 1
262 #define STARTING_FRAME_OFFSET 0
263 #define FIRST_PARM_OFFSET(FUNDECL) 0
265 /* Before the prologue, RA lives in r31. */
266 #define INCOMING_RETURN_ADDR_RTX gen_rtx_REG (Pmode, RA_REGNO)
267 #define RETURN_ADDR_RTX(C,F) nios2_get_return_address (C)
269 #define DWARF_FRAME_RETURN_COLUMN RA_REGNO
271 /* The CFA includes the pretend args. */
272 #define ARG_POINTER_CFA_OFFSET(FNDECL) \
273 (gcc_assert ((FNDECL) == current_function_decl), \
274 FIRST_PARM_OFFSET (FNDECL) + crtl->args.pretend_args_size)
276 /* Frame/arg pointer elimination settings. */
277 #define ELIMINABLE_REGS \
278 {{ ARG_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
279 { ARG_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}, \
280 { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
281 { FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}}
283 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
284 (OFFSET) = nios2_initial_elimination_offset ((FROM), (TO))
286 /* Calling convention definitions. */
287 typedef struct nios2_args
289 int regs_used;
290 } CUMULATIVE_ARGS;
292 #define NUM_ARG_REGS (LAST_ARG_REGNO - FIRST_ARG_REGNO + 1)
294 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, FNDECL, N_NAMED_ARGS) \
295 do { (CUM).regs_used = 0; } while (0)
297 #define PAD_VARARGS_DOWN \
298 (targetm.calls.function_arg_padding (TYPE_MODE (type), type) == PAD_DOWNWARD)
300 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
301 (nios2_block_reg_padding ((MODE), (TYPE), (FIRST)))
303 #define FUNCTION_ARG_REGNO_P(REGNO) \
304 ((REGNO) >= FIRST_ARG_REGNO && (REGNO) <= LAST_ARG_REGNO)
306 /* Passing function arguments on stack. */
307 #define PUSH_ARGS 0
308 #define ACCUMULATE_OUTGOING_ARGS 1
310 /* We define TARGET_RETURN_IN_MEMORY, so set to zero. */
311 #define DEFAULT_PCC_STRUCT_RETURN 0
313 /* Profiling. */
314 #define PROFILE_BEFORE_PROLOGUE
315 #define NO_PROFILE_COUNTERS 1
316 #define FUNCTION_PROFILER(FILE, LABELNO) \
317 nios2_function_profiler ((FILE), (LABELNO))
319 /* Addressing modes. */
321 #define CONSTANT_ADDRESS_P(X) \
322 (CONSTANT_P (X) && memory_address_p (SImode, X))
324 #define MAX_REGS_PER_ADDRESS 1
325 #define BASE_REG_CLASS ALL_REGS
326 #define INDEX_REG_CLASS NO_REGS
328 #define REGNO_OK_FOR_BASE_P(REGNO) nios2_regno_ok_for_base_p ((REGNO), true)
329 #define REGNO_OK_FOR_INDEX_P(REGNO) 0
331 /* Describing Relative Costs of Operations. */
332 #define MOVE_MAX 4
333 #define SLOW_BYTE_ACCESS 1
335 /* It is as good to call a constant function address as to call an address
336 kept in a register. */
337 #define NO_FUNCTION_CSE 1
339 /* Position independent code. */
341 #define PIC_OFFSET_TABLE_REGNUM 22
342 #define LEGITIMATE_PIC_OPERAND_P(X) nios2_legitimate_pic_operand_p (X)
344 /* Define output assembler language. */
346 #define ASM_APP_ON "#APP\n"
347 #define ASM_APP_OFF "#NO_APP\n"
349 #define ASM_COMMENT_START "# "
351 #define GLOBAL_ASM_OP "\t.global\t"
353 #define REGISTER_NAMES \
355 "zero", \
356 "at", \
357 "r2", \
358 "r3", \
359 "r4", \
360 "r5", \
361 "r6", \
362 "r7", \
363 "r8", \
364 "r9", \
365 "r10", \
366 "r11", \
367 "r12", \
368 "r13", \
369 "r14", \
370 "r15", \
371 "r16", \
372 "r17", \
373 "r18", \
374 "r19", \
375 "r20", \
376 "r21", \
377 "r22", \
378 "r23", \
379 "et", \
380 "bt", \
381 "gp", \
382 "sp", \
383 "fp", \
384 "ta", \
385 "ba", \
386 "ra", \
387 "status", \
388 "estatus", \
389 "bstatus", \
390 "ipri", \
391 "ecause", \
392 "pc", \
393 "fake_fp", \
394 "fake_ap", \
397 #define ADDITIONAL_REGISTER_NAMES \
399 {"r0", 0}, \
400 {"r1", 1}, \
401 {"r24", 24}, \
402 {"r25", 25}, \
403 {"r26", 26}, \
404 {"r27", 27}, \
405 {"r28", 28}, \
406 {"r29", 29}, \
407 {"r30", 30}, \
408 {"r31", 31} \
411 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE) \
412 do \
414 fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), FILE); \
415 fprintf (FILE, ".L%u\n", (unsigned) (VALUE)); \
417 while (0)
419 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL)\
420 do \
422 fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), STREAM); \
423 fprintf (STREAM, ".L%u-.L%u\n", (unsigned) (VALUE), (unsigned) (REL)); \
425 while (0)
427 /* Section directives. */
429 /* Output before read-only data. */
430 #define TEXT_SECTION_ASM_OP "\t.section\t.text"
432 /* Output before writable data. */
433 #define DATA_SECTION_ASM_OP "\t.section\t.data"
435 /* Output before uninitialized data. */
436 #define BSS_SECTION_ASM_OP "\t.section\t.bss"
438 /* Output before 'small' uninitialized data. */
439 #define SBSS_SECTION_ASM_OP "\t.section\t.sbss"
441 #ifndef IN_LIBGCC2
442 /* Default the definition of "small data" to 8 bytes. */
443 extern unsigned HOST_WIDE_INT nios2_section_threshold;
444 #endif
446 #define NIOS2_DEFAULT_GVALUE 8
448 /* This says how to output assembler code to declare an
449 uninitialized external linkage data object. Under SVR4,
450 the linker seems to want the alignment of data objects
451 to depend on their types. We do exactly that here. */
452 #undef COMMON_ASM_OP
453 #define COMMON_ASM_OP "\t.comm\t"
455 #define ASM_OUTPUT_ALIGN(FILE, LOG) \
456 do { \
457 fprintf ((FILE), "%s%d\n", ALIGN_ASM_OP, (LOG)); \
458 } while (0)
460 #undef ASM_OUTPUT_ALIGNED_COMMON
461 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN) \
462 do \
464 fprintf ((FILE), "%s", COMMON_ASM_OP); \
465 assemble_name ((FILE), (NAME)); \
466 fprintf ((FILE), "," HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE), \
467 (ALIGN) / BITS_PER_UNIT); \
469 while (0)
472 /* This says how to output assembler code to declare an
473 uninitialized internal linkage data object. Under SVR4,
474 the linker seems to want the alignment of data objects
475 to depend on their types. We do exactly that here. */
477 #undef ASM_OUTPUT_ALIGNED_LOCAL
478 #define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN) \
479 do { \
480 if ((SIZE) <= nios2_section_threshold) \
481 switch_to_section (sbss_section); \
482 else \
483 switch_to_section (bss_section); \
484 ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object"); \
485 if (!flag_inhibit_size_directive) \
486 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, SIZE); \
487 ASM_OUTPUT_ALIGN ((FILE), exact_log2((ALIGN) / BITS_PER_UNIT)); \
488 ASM_OUTPUT_LABEL(FILE, NAME); \
489 ASM_OUTPUT_SKIP((FILE), (SIZE) ? (SIZE) : 1); \
490 } while (0)
492 /* Put the jump tables in .text because when using position-independent code,
493 Nios II elf has no relocation that can represent arbitrary differences
494 between symbols in different sections. */
495 #define JUMP_TABLES_IN_TEXT_SECTION 1
497 /* Exception handling. */
499 /* Describe __builtin_eh_return. */
500 #define EH_RETURN_STACKADJ_RTX gen_rtx_REG (Pmode, LAST_RETVAL_REGNO)
501 #define EH_RETURN_DATA_REGNO(N) ((N) <= (LAST_ARG_REGNO - FIRST_ARG_REGNO) \
502 ? (N) + FIRST_ARG_REGNO : INVALID_REGNUM)
504 /* Nios II has no appropriate relocations for a 32-bit PC-relative or
505 section-relative pointer encoding. This therefore always chooses an
506 absolute representation for pointers. An unfortunate consequence of
507 this is that ld complains about the absolute fde encoding when linking
508 with -shared or -fpie, but the warning is harmless and there seems to
509 be no good way to suppress it. */
510 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \
511 (flag_pic ? DW_EH_PE_aligned : DW_EH_PE_sdata4)
513 /* Misc. parameters. */
515 #define STORE_FLAG_VALUE 1
516 #define Pmode SImode
517 #define FUNCTION_MODE QImode
519 #define CASE_VECTOR_MODE Pmode
521 #define TRULY_NOOP_TRUNCATION(OUTPREC, INPREC) 1
523 #define LOAD_EXTEND_OP(MODE) (ZERO_EXTEND)
525 #define WORD_REGISTER_OPERATIONS 1
527 #endif /* GCC_NIOS2_H */