1 /* Definitions of target machine for Altera Nios II. 2 Copyright (C) 2012-2021 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 || ((REGNO) >= 2 && (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 ACCUMULATE_OUTGOING_ARGS 1 301 302 /* We define TARGET_RETURN_IN_MEMORY, so set to zero. */ 303 #define DEFAULT_PCC_STRUCT_RETURN 0 304 305 /* Profiling. */ 306 #define PROFILE_BEFORE_PROLOGUE 307 #define NO_PROFILE_COUNTERS 1 308 #define FUNCTION_PROFILER(FILE, LABELNO) \ 309 nios2_function_profiler ((FILE), (LABELNO)) 310 311 /* Addressing modes. */ 312 313 #define CONSTANT_ADDRESS_P(X) \ 314 (CONSTANT_P (X) && memory_address_p (SImode, X)) 315 316 #define MAX_REGS_PER_ADDRESS 1 317 #define BASE_REG_CLASS ALL_REGS 318 #define INDEX_REG_CLASS NO_REGS 319 320 #define REGNO_OK_FOR_BASE_P(REGNO) nios2_regno_ok_for_base_p ((REGNO), true) 321 #define REGNO_OK_FOR_INDEX_P(REGNO) 0 322 323 /* Describing Relative Costs of Operations. */ 324 #define MOVE_MAX 4 325 #define SLOW_BYTE_ACCESS 1 326 327 /* It is as good to call a constant function address as to call an address 328 kept in a register. */ 329 #define NO_FUNCTION_CSE 1 330 331 /* Position independent code. */ 332 333 #define PIC_OFFSET_TABLE_REGNUM 22 334 #define LEGITIMATE_PIC_OPERAND_P(X) nios2_legitimate_pic_operand_p (X) 335 336 /* Define output assembler language. */ 337 338 #define ASM_APP_ON "#APP\n" 339 #define ASM_APP_OFF "#NO_APP\n" 340 341 #define ASM_COMMENT_START "# " 342 343 #define GLOBAL_ASM_OP "\t.global\t" 344 345 #define REGISTER_NAMES \ 346 { \ 347 "zero", \ 348 "at", \ 349 "r2", \ 350 "r3", \ 351 "r4", \ 352 "r5", \ 353 "r6", \ 354 "r7", \ 355 "r8", \ 356 "r9", \ 357 "r10", \ 358 "r11", \ 359 "r12", \ 360 "r13", \ 361 "r14", \ 362 "r15", \ 363 "r16", \ 364 "r17", \ 365 "r18", \ 366 "r19", \ 367 "r20", \ 368 "r21", \ 369 "r22", \ 370 "r23", \ 371 "et", \ 372 "bt", \ 373 "gp", \ 374 "sp", \ 375 "fp", \ 376 "ta", \ 377 "ba", \ 378 "ra", \ 379 "status", \ 380 "estatus", \ 381 "bstatus", \ 382 "ipri", \ 383 "ecause", \ 384 "pc", \ 385 "fake_fp", \ 386 "fake_ap", \ 387 } 388 389 #define ADDITIONAL_REGISTER_NAMES \ 390 { \ 391 {"r0", 0}, \ 392 {"r1", 1}, \ 393 {"r24", 24}, \ 394 {"r25", 25}, \ 395 {"r26", 26}, \ 396 {"r27", 27}, \ 397 {"r28", 28}, \ 398 {"r29", 29}, \ 399 {"r30", 30}, \ 400 {"r31", 31} \ 401 } 402 403 #define ASM_OUTPUT_ADDR_VEC_ELT(FILE, VALUE) \ 404 do \ 405 { \ 406 fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), FILE); \ 407 fprintf (FILE, ".L%u\n", (unsigned) (VALUE)); \ 408 } \ 409 while (0) 410 411 #define ASM_OUTPUT_ADDR_DIFF_ELT(STREAM, BODY, VALUE, REL)\ 412 do \ 413 { \ 414 fputs (integer_asm_op (POINTER_SIZE / BITS_PER_UNIT, TRUE), STREAM); \ 415 fprintf (STREAM, ".L%u-.L%u\n", (unsigned) (VALUE), (unsigned) (REL)); \ 416 } \ 417 while (0) 418 419 /* Section directives. */ 420 421 /* Output before read-only data. */ 422 #define TEXT_SECTION_ASM_OP "\t.section\t.text" 423 424 /* Output before writable data. */ 425 #define DATA_SECTION_ASM_OP "\t.section\t.data" 426 427 /* Output before uninitialized data. */ 428 #define BSS_SECTION_ASM_OP "\t.section\t.bss" 429 430 /* Output before 'small' uninitialized data. */ 431 #define SBSS_SECTION_ASM_OP "\t.section\t.sbss" 432 433 #ifndef USED_FOR_TARGET 434 /* Default the definition of "small data" to 8 bytes. */ 435 extern unsigned HOST_WIDE_INT nios2_section_threshold; 436 #endif 437 438 #define NIOS2_DEFAULT_GVALUE 8 439 440 /* This says how to output assembler code to declare an 441 uninitialized external linkage data object. Under SVR4, 442 the linker seems to want the alignment of data objects 443 to depend on their types. We do exactly that here. */ 444 #undef COMMON_ASM_OP 445 #define COMMON_ASM_OP "\t.comm\t" 446 447 #define ASM_OUTPUT_ALIGN(FILE, LOG) \ 448 do { \ 449 fprintf ((FILE), "%s%d\n", ALIGN_ASM_OP, (LOG)); \ 450 } while (0) 451 452 #undef ASM_OUTPUT_ALIGNED_COMMON 453 #define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN) \ 454 do \ 455 { \ 456 fprintf ((FILE), "%s", COMMON_ASM_OP); \ 457 assemble_name ((FILE), (NAME)); \ 458 fprintf ((FILE), "," HOST_WIDE_INT_PRINT_UNSIGNED",%u\n", (SIZE), \ 459 (ALIGN) / BITS_PER_UNIT); \ 460 } \ 461 while (0) 462 463 464 /* This says how to output assembler code to declare an 465 uninitialized internal linkage data object. Under SVR4, 466 the linker seems to want the alignment of data objects 467 to depend on their types. We do exactly that here. */ 468 469 #undef ASM_OUTPUT_ALIGNED_DECL_LOCAL 470 #define ASM_OUTPUT_ALIGNED_DECL_LOCAL(FILE, DECL, NAME, SIZE, ALIGN) \ 471 do { \ 472 if (targetm.in_small_data_p (DECL)) \ 473 switch_to_section (sbss_section); \ 474 else \ 475 switch_to_section (bss_section); \ 476 ASM_OUTPUT_TYPE_DIRECTIVE (FILE, NAME, "object"); \ 477 if (!flag_inhibit_size_directive) \ 478 ASM_OUTPUT_SIZE_DIRECTIVE (FILE, NAME, SIZE); \ 479 ASM_OUTPUT_ALIGN ((FILE), exact_log2((ALIGN) / BITS_PER_UNIT)); \ 480 ASM_OUTPUT_LABEL(FILE, NAME); \ 481 ASM_OUTPUT_SKIP((FILE), (SIZE) ? (SIZE) : 1); \ 482 } while (0) 483 484 /* Put the jump tables in .text because when using position-independent code, 485 Nios II elf has no relocation that can represent arbitrary differences 486 between symbols in different sections. */ 487 #define JUMP_TABLES_IN_TEXT_SECTION 1 488 489 /* Exception handling. */ 490 491 /* Describe __builtin_eh_return. */ 492 #define EH_RETURN_STACKADJ_RTX gen_rtx_REG (Pmode, LAST_RETVAL_REGNO) 493 #define EH_RETURN_DATA_REGNO(N) ((N) <= (LAST_ARG_REGNO - FIRST_ARG_REGNO) \ 494 ? (N) + FIRST_ARG_REGNO : INVALID_REGNUM) 495 496 /* For PIC, use indirect for global references; it'll end up using a dynamic 497 relocation, which we want to keep out of read-only EH sections. 498 For local references, we want to use GOT-relative offsets provided 499 the assembler supports them. For non-PIC, use an absolute encoding. */ 500 #ifdef HAVE_AS_NIOS2_GOTOFF_RELOCATION 501 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \ 502 (flag_pic \ 503 ? ((GLOBAL) \ 504 ? DW_EH_PE_indirect | DW_EH_PE_absptr \ 505 : DW_EH_PE_datarel | DW_EH_PE_sdata4) \ 506 : DW_EH_PE_absptr) 507 508 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \ 509 do { \ 510 if (((ENCODING) & 0xf0) == DW_EH_PE_datarel) \ 511 { \ 512 fputs ("\t.4byte %gotoff(", FILE); \ 513 output_addr_const (FILE, ADDR); \ 514 fputs (")", FILE); \ 515 goto DONE; \ 516 } \ 517 } while (0) 518 519 #else 520 /* We don't have %gotoff support in the assembler. Fall back to the encoding 521 it used to use instead before the assembler was fixed. This has known 522 bugs but mostly works. */ 523 #define ASM_PREFERRED_EH_DATA_FORMAT(CODE, GLOBAL) \ 524 (flag_pic \ 525 ? ((GLOBAL) \ 526 ? DW_EH_PE_indirect | DW_EH_PE_absptr \ 527 : DW_EH_PE_aligned) \ 528 : DW_EH_PE_absptr) 529 #endif 530 531 /* Misc. parameters. */ 532 533 #define STORE_FLAG_VALUE 1 534 #define Pmode SImode 535 #define FUNCTION_MODE QImode 536 537 #define CASE_VECTOR_MODE Pmode 538 539 #define LOAD_EXTEND_OP(MODE) (ZERO_EXTEND) 540 541 #define WORD_REGISTER_OPERATIONS 1 542 543 #endif /* GCC_NIOS2_H */ 544