gcc/config/nios2/nios2.h

   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.
   6
   7    This file is part of GCC.
   8
   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.
  13
  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.
  18
  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/>.  */
  22
  23 #ifndef GCC_NIOS2_H
  24 #define GCC_NIOS2_H
  25
  26 /* Indicate R2 ISA level support.  */
  27 #define TARGET_ARCH_R2 (nios2_arch_option == ARCH_R2)
  28
  29 /* FPU insn codes declared here.  */
  30 #include "config/nios2/nios2-opts.h"
  31
  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)
  46
  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
  52
  53 /* Default target_flags if no switches specified.  */
  54 #ifndef TARGET_DEFAULT
  55 # define TARGET_DEFAULT (MASK_HAS_MUL | TARGET_ENDIAN_DEFAULT)
  56 #endif
  57
  58 #define OPTION_DEFAULT_SPECS \
  59   {"arch", "%{!march=*:%{!mcpu=*:-march=%(VALUE)}}" }
  60
  61 #define CC1_SPEC "%{G*}"
  62
  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
  72
  73 #define LINK_SPEC LINK_SPEC_ENDIAN \
  74   " %{shared:-shared} \
  75     %{static:-Bstatic}"
  76
  77
  78 /* Storage layout.  */
  79
  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
  94
  95 #define LABEL_ALIGN(LABEL) nios2_label_align (LABEL)
  96
  97 /* Layout of source language data types.  */
  98
  99 #define INT_TYPE_SIZE 32
 100 #define SHORT_TYPE_SIZE 16
 101 #define LONG_TYPE_SIZE 32
 102 #define LONG_LONG_TYPE_SIZE 64
 103 #define FLOAT_TYPE_SIZE 32
 104 #define DOUBLE_TYPE_SIZE 64
 105 #define LONG_DOUBLE_TYPE_SIZE DOUBLE_TYPE_SIZE
 106
 107 #undef SIZE_TYPE
 108 #define SIZE_TYPE "unsigned int"
 109
 110 #undef PTRDIFF_TYPE
 111 #define PTRDIFF_TYPE "int"
 112
 113
 114 /* Basic characteristics of Nios II registers:
 115
 116    Regno  Name
 117    0      r0       zero    always zero
 118    1      r1       at      Assembler Temporary
 119    2-3    r2-r3            Return Location
 120    4-7    r4-r7            Register Arguments
 121    8-15   r8-r15           Caller Saved Registers
 122    16-22  r16-r22          Callee Saved Registers
 123    22     r22              Global Offset Table pointer (Linux ABI only)
 124    23     r23              Thread pointer (Linux ABI only)
 125    24     r24      et      Exception Temporary
 126    25     r25      bt      Breakpoint Temporary
 127    26     r26      gp      Global Pointer
 128    27     r27      sp      Stack Pointer
 129    28     r28      fp      Frame Pointer
 130    29     r29      ea      Exception Return Address
 131    30     r30      ba      Breakpoint Return Address
 132    31     r31      ra      Return Address
 133
 134    32     ctl0     status
 135    33     ctl1     estatus STATUS saved by exception
 136    34     ctl2     bstatus STATUS saved by break
 137    35     ctl3     ipri    Interrupt Priority Mask
 138    36     ctl4     ecause  Exception Cause
 139
 140    37     pc               Not an actual register
 141
 142    38     fake_fp          Fake Frame Pointer (always eliminated)
 143    39     fake_ap          Fake Argument Pointer (always eliminated)
 144    40                      First Pseudo Register
 145
 146    In addition, r12 is used as the static chain register and r13, r14, and r15
 147    are clobbered by PLT code sequences.
 148
 149    The definitions for all the hard register numbers are located in nios2.md.
 150 */
 151
 152 #define FIXED_REGISTERS                      \
 153   {                                          \
 154 /*        +0  1  2  3  4  5  6  7  8  9 */   \
 155 /*   0 */  1, 1, 0, 0, 0, 0, 0, 0, 0, 0,     \
 156 /*  10 */  0, 0, 0, 0, 0, 0, 0, 0, 0, 0,     \
 157 /*  20 */  0, 0, TARGET_LINUX_ABI, TARGET_LINUX_ABI, 1, 1, 1, 1, 0, 1,     \
 158 /*  30 */  1, 0, 1, 1, 1, 1, 1, 1, 1, 1,     \
 159   }
 160
 161 /* Call used == caller saved + fixed regs + args + ret vals.  */
 162 #define CALL_USED_REGISTERS                  \
 163   {                                          \
 164 /*        +0  1  2  3  4  5  6  7  8  9 */   \
 165 /*   0 */  1, 1, 1, 1, 1, 1, 1, 1, 1, 1,     \
 166 /*  10 */  1, 1, 1, 1, 1, 1, 0, 0, 0, 0,     \
 167 /*  20 */  0, 0, TARGET_LINUX_ABI, TARGET_LINUX_ABI, 1, 1, 1, 1, 0, 1,     \
 168 /*  30 */  1, 1, 1, 1, 1, 1, 1, 1, 1, 1,     \
 169   }
 170
 171 /* Order in which to allocate registers.  Each register must be
 172    listed once.  This is the default ordering for R1 and non-CDX R2
 173    code.  For CDX, we overwrite this in ADJUST_REG_ALLOC_ORDER.  */
 174 #define REG_ALLOC_ORDER                                                 \
 175   { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, \
 176       20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, \
 177       37, 38, 39 }
 178
 179 #define ADJUST_REG_ALLOC_ORDER nios2_adjust_reg_alloc_order ()
 180
 181 /* Caller-save costs can be less emphasized under R2 CDX, where we can
 182    use push.n/pop.n.  */
 183 #define HONOR_REG_ALLOC_ORDER (TARGET_HAS_CDX)
 184
 185 /* Register Classes.  */
 186
 187 enum reg_class
 188 {
 189   NO_REGS,
 190   SIB_REGS,
 191   IJMP_REGS,
 192   GP_REGS,
 193   ALL_REGS,
 194   LIM_REG_CLASSES
 195 };
 196
 197 #define N_REG_CLASSES (int) LIM_REG_CLASSES
 198
 199 #define REG_CLASS_NAMES   \
 200   {  "NO_REGS",           \
 201      "SIB_REGS",          \
 202      "IJMP_REGS",         \
 203      "GP_REGS",           \
 204      "ALL_REGS" }
 205
 206 #define GENERAL_REGS ALL_REGS
 207
 208 #define REG_CLASS_CONTENTS                      \
 209   {                                             \
 210     /* NO_REGS    */ { 0, 0},                   \
 211     /* SIB_REGS   */ { 0xfe0c, 0},              \
 212     /* IJMP_REGS  */ { 0x7fffffff, 0},          \
 213     /* GP_REGS    */ {~0, 0},                   \
 214     /* ALL_REGS   */ {~0,~0}                    \
 215   }
 216
 217
 218 #define GP_REG_P(REGNO) ((unsigned)(REGNO) <= LAST_GP_REG)
 219 #define REGNO_REG_CLASS(REGNO) (GP_REG_P (REGNO) ? GP_REGS : ALL_REGS)
 220 #define CLASS_MAX_NREGS(CLASS, MODE)                                    \
 221   ((GET_MODE_SIZE (MODE) + UNITS_PER_WORD - 1) / UNITS_PER_WORD)
 222
 223 #define CDX_REG_P(REGNO)                                                \
 224   ((REGNO) == 16 || (REGNO) == 17 || (2 <= (REGNO) && (REGNO) <= 7))
 225
 226 /* Tests for various kinds of constants used in the Nios II port.  */
 227
 228 #define SMALL_INT(X) ((unsigned HOST_WIDE_INT)(X) + 0x8000 < 0x10000)
 229 #define SMALL_INT12(X) ((unsigned HOST_WIDE_INT)(X) + 0x800 < 0x1000)
 230 #define SMALL_INT_UNSIGNED(X) ((X) >= 0 && (X) < 0x10000)
 231 #define UPPER16_INT(X) (((X) & 0xffff) == 0)
 232 #define SHIFT_INT(X) ((X) >= 0 && (X) <= 31)
 233 #define RDWRCTL_INT(X) ((X) >= 0 && (X) <= 31)
 234 #define CUSTOM_INSN_OPCODE(X) ((X) >= 0 && (X) <= 255)
 235 #define ANDCLEAR_INT(X) \
 236   (((X) & 0xffff) == 0xffff || (((X) >> 16) & 0xffff) == 0xffff)
 237
 238 /* Say that the epilogue uses the return address register.  Note that
 239    in the case of sibcalls, the values "used by the epilogue" are
 240    considered live at the start of the called function.  */
 241 #define EPILOGUE_USES(REGNO) (epilogue_completed && (REGNO) == RA_REGNO)
 242
 243 /* EXIT_IGNORE_STACK should be nonzero if, when returning from a function,
 244    the stack pointer does not matter.  The value is tested only in
 245    functions that have frame pointers.
 246    No definition is equivalent to always zero.  */
 247
 248 #define EXIT_IGNORE_STACK 1
 249
 250 /* Trampolines use a 5-instruction sequence.  */
 251 #define TRAMPOLINE_SIZE 20
 252
 253 /* Stack layout.  */
 254 #define STACK_GROWS_DOWNWARD 1
 255 #define FRAME_GROWS_DOWNWARD 1
 256 #define FIRST_PARM_OFFSET(FUNDECL) 0
 257
 258 /* Before the prologue, RA lives in r31.  */
 259 #define INCOMING_RETURN_ADDR_RTX  gen_rtx_REG (Pmode, RA_REGNO)
 260 #define RETURN_ADDR_RTX(C,F) nios2_get_return_address (C)
 261
 262 #define DWARF_FRAME_RETURN_COLUMN RA_REGNO
 263
 264 /* The CFA includes the pretend args.  */
 265 #define ARG_POINTER_CFA_OFFSET(FNDECL) \
 266   (gcc_assert ((FNDECL) == current_function_decl), \
 267    FIRST_PARM_OFFSET (FNDECL) + crtl->args.pretend_args_size)
 268
 269 /* Frame/arg pointer elimination settings.  */
 270 #define ELIMINABLE_REGS                                                 \
 271 {{ ARG_POINTER_REGNUM,   STACK_POINTER_REGNUM},                         \
 272  { ARG_POINTER_REGNUM,   HARD_FRAME_POINTER_REGNUM},                    \
 273  { FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM},                         \
 274  { FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}}
 275
 276 #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
 277   (OFFSET) = nios2_initial_elimination_offset ((FROM), (TO))
 278
 279 /* Calling convention definitions.  */
 280 typedef struct nios2_args
 281 {
 282   int regs_used;
 283 } CUMULATIVE_ARGS;
 284
 285 #define NUM_ARG_REGS (LAST_ARG_REGNO - FIRST_ARG_REGNO + 1)
 286
 287 #define INIT_CUMULATIVE_ARGS(CUM, FNTYPE, LIBNAME, FNDECL, N_NAMED_ARGS) \
 288   do { (CUM).regs_used = 0; } while (0)
 289
 290 #define PAD_VARARGS_DOWN \
 291   (targetm.calls.function_arg_padding (TYPE_MODE (type), type) == PAD_DOWNWARD)
 292
 293 #define BLOCK_REG_PADDING(MODE, TYPE, FIRST) \
 294   (nios2_block_reg_padding ((MODE), (TYPE), (FIRST)))
 295
 296 #define FUNCTION_ARG_REGNO_P(REGNO) \
 297   ((REGNO) >= FIRST_ARG_REGNO && (REGNO) <= LAST_ARG_REGNO)
 298
 299 /* Passing function arguments on stack.  */
 300 #define PUSH_ARGS 0
 301 #define ACCUMULATE_OUTGOING_ARGS 1
 302
 303 /* We define TARGET_RETURN_IN_MEMORY, so set to zero.  */
 304 #define DEFAULT_PCC_STRUCT_RETURN 0
 305
 306 /* Profiling.  */
 307 #define PROFILE_BEFORE_PROLOGUE
 308 #define NO_PROFILE_COUNTERS 1
 309 #define FUNCTION_PROFILER(FILE, LABELNO) \
 310   nios2_function_profiler ((FILE), (LABELNO))
 311
 312 /* Addressing modes.  */
 313
 314 #define CONSTANT_ADDRESS_P(X) \
 315   (CONSTANT_P (X) && memory_address_p (SImode, X))
 316
 317 #define MAX_REGS_PER_ADDRESS 1
 318 #define BASE_REG_CLASS ALL_REGS
 319 #define INDEX_REG_CLASS NO_REGS
 320
 321 #define REGNO_OK_FOR_BASE_P(REGNO) nios2_regno_ok_for_base_p ((REGNO), true)
 322 #define REGNO_OK_FOR_INDEX_P(REGNO) 0
 323
 324 /* Describing Relative Costs of Operations.  */
 325 #define MOVE_MAX 4
 326 #define SLOW_BYTE_ACCESS 1
 327
 328 /* It is as good to call a constant function address as to call an address
 329    kept in a register.  */
 330 #define NO_FUNCTION_CSE 1
 331
 332 /* Position independent code.  */
 333
 334 #define PIC_OFFSET_TABLE_REGNUM 22
 335 #define LEGITIMATE_PIC_OPERAND_P(X) nios2_legitimate_pic_operand_p (X)
 336
 337 /* Define output assembler language.  */
 338
 339 #define ASM_APP_ON "#APP\n"
 340 #define ASM_APP_OFF "#NO_APP\n"
 341
 342 #define ASM_COMMENT_START "# "
 343
 344 #define GLOBAL_ASM_OP "\t.global\t"
 345
 346 #define REGISTER_NAMES \
 347   {                    \
 348     "zero", \
 349     "at", \
 350     "r2", \
 351     "r3", \
 352     "r4", \
 353     "r5", \
 354     "r6", \
 355     "r7", \
 356     "r8", \
 357     "r9", \
 358     "r10", \
 359     "r11", \
 360     "r12", \
 361     "r13", \
 362     "r14", \
 363     "r15", \
 364     "r16", \
 365     "r17", \
 366     "r18", \
 367     "r19", \
 368     "r20", \
 369     "r21", \
 370     "r22", \
 371     "r23", \
 372     "et", \
 373     "bt", \
 374     "gp", \
 375     "sp", \
 376     "fp", \
 377     "ta", \
 378     "ba", \
 379     "ra", \
 380     "status", \
 381     "estatus", \
 382     "bstatus", \
 383     "ipri", \
 384     "ecause", \
 385     "pc", \
 386     "fake_fp", \
 387     "fake_ap", \
 388 }
 389
 390 #define ADDITIONAL_REGISTER_NAMES       \
 391 {                                       \
 392   {"r0", 0},                            \
 393   {"r1", 1},                            \
 394   {"r24", 24},                          \
 395   {"r25", 25},                          \
 396   {"r26", 26},                          \
 397   {"r27", 27},                          \
 398   {"r28", 28},                          \
 399   {"r29", 29},                          \
 400   {"r30", 30},                          \
 401   {"r31", 31}                           \
 402 }
 403
 404 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE)  \
 405   do                                                                    \
 406     {                                                                   \
 407       fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), FILE); \
 408       fprintf (FILE, ".L%u\n", (unsigned) (VALUE));                     \
 409     }                                                                   \
 410   while (0)
 411
 412 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL)\
 413   do                                                                    \
 414     {                                                                   \
 415       fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), STREAM); \
 416       fprintf (STREAM, ".L%u-.L%u\n", (unsigned) (VALUE), (unsigned) (REL)); \
 417     }                                                                   \
 418   while (0)
 419
 420 /* Section directives.  */
 421
 422 /* Output before read-only data.  */
 423 #define TEXT_SECTION_ASM_OP "\t.section\t.text"
 424
 425 /* Output before writable data.  */
 426 #define DATA_SECTION_ASM_OP "\t.section\t.data"
 427
 428 /* Output before uninitialized data.  */
 429 #define BSS_SECTION_ASM_OP "\t.section\t.bss"
 430
 431 /* Output before 'small' uninitialized data.  */
 432 #define SBSS_SECTION_ASM_OP "\t.section\t.sbss"
 433
 434 #ifndef IN_LIBGCC2
 435 /* Default the definition of "small data" to 8 bytes.  */
 436 extern unsigned HOST_WIDE_INT nios2_section_threshold;
 437 #endif
 438
 439 #define NIOS2_DEFAULT_GVALUE 8
 440
 441 /* This says how to output assembler code to declare an
 442    uninitialized external linkage data object.  Under SVR4,
 443    the linker seems to want the alignment of data objects
 444    to depend on their types.  We do exactly that here.  */
 445 #undef COMMON_ASM_OP
 446 #define COMMON_ASM_OP   "\t.comm\t"
 447
 448 #define ASM_OUTPUT_ALIGN(FILE, LOG)                  \
 449   do {                                               \
 450     fprintf ((FILE), "%s%d\n", ALIGN_ASM_OP, (LOG)); \
 451   } while (0)
 452
 453 #undef  ASM_OUTPUT_ALIGNED_COMMON
 454 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)              \
 455 do                                                                      \
 456   {                                                                     \
 457     fprintf ((FILE), "%s", COMMON_ASM_OP);                              \
 458     assemble_name ((FILE), (NAME));                                     \
 459     fprintf ((FILE), "," HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE),   \
 460              (ALIGN) / BITS_PER_UNIT);                                  \
 461   }                                                                     \
 462 while (0)
 463
 464
 465 /* This says how to output assembler code to declare an
 466    uninitialized internal linkage data object.  Under SVR4,
 467    the linker seems to want the alignment of data objects
 468    to depend on their types.  We do exactly that here.  */
 469
 470 #undef  ASM_OUTPUT_ALIGNED_LOCAL
 471 #define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN)               \
 472 do {                                                                    \
 473   if ((SIZE) <= nios2_section_threshold)                                \
 474     switch_to_section (sbss_section);                                   \
 475   else                                                                  \
 476     switch_to_section (bss_section);                                    \
 477   ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object");                     \
 478   if (!flag_inhibit_size_directive)                                     \
 479     ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, SIZE);                       \
 480   ASM_OUTPUT_ALIGN ((FILE), exact_log2((ALIGN) / BITS_PER_UNIT));       \
 481   ASM_OUTPUT_LABEL(FILE, NAME);                                         \
 482   ASM_OUTPUT_SKIP((FILE), (SIZE) ? (SIZE) : 1);                         \
 483 } while (0)
 484
 485 /* Put the jump tables in .text because when using position-independent code,
 486    Nios II elf has no relocation that can represent arbitrary differences
 487    between symbols in different sections.  */
 488 #define JUMP_TABLES_IN_TEXT_SECTION 1
 489
 490 /* Exception handling.  */
 491
 492 /* Describe __builtin_eh_return.  */
 493 #define EH_RETURN_STACKADJ_RTX gen_rtx_REG (Pmode, LAST_RETVAL_REGNO)
 494 #define EH_RETURN_DATA_REGNO(N) ((N) <= (LAST_ARG_REGNO - FIRST_ARG_REGNO) \
 495                                  ? (N) + FIRST_ARG_REGNO : INVALID_REGNUM)
 496
 497 /* Nios II has no appropriate relocations for a 32-bit PC-relative or
 498    section-relative pointer encoding.  This therefore always chooses an
 499    absolute representation for pointers.  An unfortunate consequence of
 500    this is that ld complains about the absolute fde encoding when linking
 501    with -shared or -fpie, but the warning is harmless and there seems to
 502    be no good way to suppress it.  */
 503 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL)              \
 504   (flag_pic ? DW_EH_PE_aligned : DW_EH_PE_sdata4)
 505
 506 /* Misc. parameters.  */
 507
 508 #define STORE_FLAG_VALUE 1
 509 #define Pmode SImode
 510 #define FUNCTION_MODE QImode
 511
 512 #define CASE_VECTOR_MODE Pmode
 513
 514 #define LOAD_EXTEND_OP(MODE) (ZERO_EXTEND)
 515
 516 #define WORD_REGISTER_OPERATIONS 1
 517
 518 #endif /* GCC_NIOS2_H */