asm.h revision 1.13
1 /* $NetBSD: asm.h,v 1.13 1997/04/08 00:19:04 cgd Exp $ */ 2 3 /* 4 * Copyright (c) 1991,1990,1989,1994,1995,1996 Carnegie Mellon University 5 * All Rights Reserved. 6 * 7 * Permission to use, copy, modify and distribute this software and its 8 * documentation is hereby granted, provided that both the copyright 9 * notice and this permission notice appear in all copies of the 10 * software, derivative works or modified versions, and any portions 11 * thereof, and that both notices appear in supporting documentation. 12 * 13 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 14 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 15 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 16 * 17 * Carnegie Mellon requests users of this software to return to 18 * 19 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU 20 * School of Computer Science 21 * Carnegie Mellon University 22 * Pittsburgh PA 15213-3890 23 * 24 * any improvements or extensions that they make and grant Carnegie Mellon 25 * the rights to redistribute these changes. 26 */ 27 28 /* 29 * Assembly coding style 30 * 31 * This file contains macros and register defines to 32 * aid in writing more readable assembly code. 33 * Some rules to make assembly code understandable by 34 * a debugger are also noted. 35 * 36 * The document 37 * 38 * "ALPHA Calling Standard", DEC 27-Apr-90 39 * 40 * defines (a superset of) the rules and conventions 41 * we use. While we make no promise of adhering to 42 * such standard and its evolution (esp where we 43 * can get faster code paths) it is certainly intended 44 * that we be interoperable with such standard. 45 * 46 * In this sense, this file is a proper part of the 47 * definition of the (software) Alpha architecture. 48 */ 49 50 /* 51 * Symbolic register names and register saving rules 52 * 53 * Legend: 54 * T Saved by caller (Temporaries) 55 * S Saved by callee (call-Safe registers) 56 */ 57 58 #define v0 $0 /* (T) return value */ 59 #define t0 $1 /* (T) temporary registers */ 60 #define t1 $2 61 #define t2 $3 62 #define t3 $4 63 #define t4 $5 64 #define t5 $6 65 #define t6 $7 66 #define t7 $8 67 68 #define s0 $9 /* (S) call-safe registers */ 69 #define s1 $10 70 #define s2 $11 71 #define s3 $12 72 #define s4 $13 73 #define s5 $14 74 #define s6 $15 75 #define a0 $16 /* (T) argument registers */ 76 #define a1 $17 77 #define a2 $18 78 #define a3 $19 79 #define a4 $20 80 #define a5 $21 81 #define t8 $22 /* (T) temporary registers */ 82 #define t9 $23 83 #define t10 $24 84 #define t11 $25 85 #define ra $26 /* (T) return address */ 86 #define t12 $27 /* (T) another temporary */ 87 #define at_reg $28 /* (T) assembler scratch */ 88 #define gp $29 /* (T) (local) data pointer */ 89 #define sp $30 /* (S) stack pointer */ 90 #define zero $31 /* wired zero */ 91 92 /* Floating point registers (XXXX VERIFY THIS) */ 93 #define fv0 $f0 /* (T) return value (real) */ 94 #define fv1 $f1 /* (T) return value (imaginary)*/ 95 #define ft0 fv1 96 #define fs0 $f2 /* (S) call-safe registers */ 97 #define fs1 $f3 98 #define fs2 $f4 99 #define fs3 $f5 100 #define fs4 $f6 101 #define fs5 $f7 102 #define fs6 $f8 103 #define fs7 $f9 104 #define ft1 $f10 /* (T) temporary registers */ 105 #define ft2 $f11 106 #define ft3 $f12 107 #define ft4 $f13 108 #define ft5 $f14 109 #define ft6 $f15 110 #define fa0 $f16 /* (T) argument registers */ 111 #define fa1 $f17 112 #define fa2 $f18 113 #define fa3 $f19 114 #define fa4 $f20 115 #define fa5 $f21 116 #define ft7 $f22 /* (T) more temporaries */ 117 #define ft8 $f23 118 #define ft9 $f24 119 #define ft10 $f25 120 #define ft11 $f26 121 #define ft12 $f27 122 #define ft13 $f28 123 #define ft14 $f29 124 #define ft15 $f30 125 #define fzero $f31 /* wired zero */ 126 127 128 /* Other DEC standard names */ 129 #define ai $25 /* (T) argument information */ 130 #define pv $27 /* (T) procedure value */ 131 132 133 /* 134 * Useful stuff. 135 */ 136 #ifdef __STDC__ 137 #define __CONCAT(a,b) a ## b 138 #else 139 #define __CONCAT(a,b) a/**/b 140 #endif 141 #define ___CONCAT(a,b) __CONCAT(a,b) 142 143 /* 144 * Macro to make a local label name. 145 */ 146 #define LLABEL(name,num) ___CONCAT(___CONCAT(L,name),num) 147 148 /* 149 * 150 * Debuggers need symbol table information to be able to properly 151 * decode a stack trace. The minimum that should be provided is: 152 * 153 * name: 154 * .proc name,numargs 155 * 156 * where "name" is the function's name; 157 * "numargs" how many arguments it expects. For varargs 158 * procedures this should be a negative number, 159 * indicating the minimum required number of 160 * arguments (which is at least 1); 161 * 162 * NESTED functions (functions that call other functions) should define 163 * how they handle their stack frame in a .frame directive: 164 * 165 * .frame framesize, pc_reg, i_mask, f_mask 166 * 167 * where "framesize" is the size of the frame for this function, in bytes. 168 * That is: 169 * new_sp + framesize == old_sp 170 * Framesizes should be rounded to a cacheline size. 171 * Note that old_sp plays the role of a conventional 172 * "frame pointer"; 173 * "pc_reg" is either a register which preserves the caller's PC 174 * or 'std', if std the saved PC should be stored at 175 * old_sp-8 176 * "i_mask" is a bitmask that indicates which of the integer 177 * registers are saved. See the M_xx defines at the 178 * end for the encoding of this 32bit value. 179 * "f_mask" is the same, for floating point registers. 180 * 181 * Note that registers should be saved starting at "old_sp-8", where the 182 * return address should be stored. Other registers follow at -16-24-32.. 183 * starting from register 0 (if saved) and up. Then float registers (ifany) 184 * are saved. 185 * 186 * If you need to alias a leaf function, or to provide multiple entry points 187 * use the LEAF() macro for the main entry point and XLEAF() for the other 188 * additional/alternate entry points. 189 * "XLEAF"s must be nested within a "LEAF" and a ".end". 190 * Similar rules for nested routines, e.g. use NESTED/XNESTED 191 * Symbols that should not be exported can be declared with the STATIC_xxx 192 * macros. 193 * 194 * All functions must be terminated by the END macro 195 * 196 * It is conceivable, although currently at the limits of compiler 197 * technology, that while performing inter-procedural optimizations 198 * the compiler/linker be able to avoid unnecessary register spills 199 * if told about the register usage of LEAF procedures (and by transitive 200 * closure of NESTED procedures as well). Assembly code can help 201 * this process using the .reguse directive: 202 * 203 * .reguse i_mask, f_mask 204 * 205 * where the register masks are built as above or-ing M_xx defines. 206 * 207 * 208 * All symbols are internal unless EXPORTed. Symbols that are IMPORTed 209 * must be appropriately described to the debugger. 210 * 211 */ 212 213 /* 214 * MCOUNT 215 */ 216 217 #ifndef GPROF 218 #define MCOUNT /* nothing */ 219 #else 220 #define MCOUNT \ 221 .set noat; \ 222 jsr at_reg,_mcount; \ 223 .set at 224 #endif 225 226 /* 227 * LEAF 228 * Declare a global leaf function. 229 * A leaf function does not call other functions AND does not 230 * use any register that is callee-saved AND does not modify 231 * the stack pointer. 232 */ 233 #define LEAF(_name_,_n_args_) \ 234 .globl _name_; \ 235 .ent _name_ 0; \ 236 _name_:; \ 237 .frame sp,0,ra; \ 238 MCOUNT 239 /* should have been 240 .proc _name_,_n_args_; \ 241 .frame 0,ra,0,0 242 */ 243 244 #define LEAF_NOPROFILE(_name_,_n_args_) \ 245 .globl _name_; \ 246 .ent _name_ 0; \ 247 _name_:; \ 248 .frame sp,0,ra 249 /* should have been 250 .proc _name_,_n_args_; \ 251 .frame 0,ra,0,0 252 */ 253 254 /* 255 * STATIC_LEAF 256 * Declare a local leaf function. 257 */ 258 #define STATIC_LEAF(_name_,_n_args_) \ 259 .ent _name_ 0; \ 260 _name_:; \ 261 .frame sp,0,ra; \ 262 MCOUNT 263 /* should have been 264 .proc _name_,_n_args_; \ 265 .frame 0,ra,0,0 266 */ 267 /* 268 * XLEAF 269 * Global alias for a leaf function, or alternate entry point 270 */ 271 #define XLEAF(_name_,_n_args_) \ 272 .globl _name_; \ 273 .aent _name_ 0; \ 274 _name_: 275 /* should have been 276 .aproc _name_,_n_args_; 277 */ 278 279 /* 280 * STATIC_XLEAF 281 * Local alias for a leaf function, or alternate entry point 282 */ 283 #define STATIC_XLEAF(_name_,_n_args_) \ 284 .aent _name_ 0; \ 285 _name_: 286 /* should have been 287 .aproc _name_,_n_args_; 288 */ 289 290 /* 291 * NESTED 292 * Declare a (global) nested function 293 * A nested function calls other functions and needs 294 * therefore stack space to save/restore registers. 295 */ 296 #define NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 297 .globl _name_; \ 298 .ent _name_ 0; \ 299 _name_:; \ 300 .frame sp,_framesize_,_pc_reg_; \ 301 .livereg _i_mask_,_f_mask_; \ 302 MCOUNT 303 /* should have been 304 .proc _name_,_n_args_; \ 305 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 306 */ 307 308 #define NESTED_NOPROFILE(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 309 .globl _name_; \ 310 .ent _name_ 0; \ 311 _name_:; \ 312 .frame sp,_framesize_,_pc_reg_; \ 313 .livereg _i_mask_,_f_mask_ 314 /* should have been 315 .proc _name_,_n_args_; \ 316 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 317 */ 318 319 /* 320 * STATIC_NESTED 321 * Declare a local nested function. 322 */ 323 #define STATIC_NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 324 .ent _name_ 0; \ 325 _name_:; \ 326 .frame sp,_framesize_,_pc_reg_; \ 327 .livereg _i_mask_,_f_mask_; \ 328 MCOUNT 329 /* should have been 330 .proc _name_,_n_args_; \ 331 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 332 */ 333 334 /* 335 * XNESTED 336 * Same as XLEAF, for a nested function. 337 */ 338 #define XNESTED(_name_,_n_args_) \ 339 .globl _name_; \ 340 .aent _name_ 0; \ 341 _name_: 342 /* should have been 343 .aproc _name_,_n_args_; 344 */ 345 346 347 /* 348 * STATIC_XNESTED 349 * Same as STATIC_XLEAF, for a nested function. 350 */ 351 #define STATIC_XNESTED(_name_,_n_args_) \ 352 .aent _name_ 0; \ 353 _name_: 354 /* should have been 355 .aproc _name_,_n_args_; 356 */ 357 358 359 /* 360 * END 361 * Function delimiter 362 */ 363 #define END(_name_) \ 364 .end _name_ 365 366 367 /* 368 * CALL 369 * Function invocation 370 */ 371 #define CALL(_name_) \ 372 jsr ra,_name_; \ 373 ldgp gp,0(ra) 374 /* but this would cover longer jumps 375 br ra,.+4; \ 376 bsr ra,_name_ 377 */ 378 379 380 /* 381 * RET 382 * Return from function 383 */ 384 #define RET \ 385 ret zero,(ra),1 386 387 388 /* 389 * EXPORT 390 * Export a symbol 391 */ 392 #define EXPORT(_name_) \ 393 .globl _name_; \ 394 _name_: 395 396 397 /* 398 * IMPORT 399 * Make an external name visible, typecheck the size 400 */ 401 #define IMPORT(_name_, _size_) \ 402 .extern _name_,_size_ 403 404 405 /* 406 * ABS 407 * Define an absolute symbol 408 */ 409 #define ABS(_name_, _value_) \ 410 .globl _name_; \ 411 _name_ = _value_ 412 413 414 /* 415 * BSS 416 * Allocate un-initialized space for a global symbol 417 */ 418 #define BSS(_name_,_numbytes_) \ 419 .comm _name_,_numbytes_ 420 421 /* 422 * VECTOR 423 * Make an exception entry point look like a called function, 424 * to make it digestible to the debugger (KERNEL only) 425 */ 426 #define VECTOR(_name_, _i_mask_) \ 427 .globl _name_; \ 428 .ent _name_ 0; \ 429 _name_:; \ 430 .mask _i_mask_|IM_EXC,0; \ 431 .frame sp,MSS_SIZE,ra; 432 /* .livereg _i_mask_|IM_EXC,0 433 /* should have been 434 .proc _name_,1; \ 435 .frame MSS_SIZE,$31,_i_mask_,0; \ 436 */ 437 438 /* 439 * MSG 440 * Allocate space for a message (a read-only ascii string) 441 */ 442 #define ASCIZ .asciz 443 #define MSG(msg,reg,label) \ 444 lda reg, label; \ 445 .data; \ 446 label: ASCIZ msg; \ 447 .text; 448 449 /* 450 * PRINTF 451 * Print a message 452 */ 453 #define PRINTF(msg,label) \ 454 MSG(msg,a0,label); \ 455 CALL(printf) 456 457 /* 458 * PANIC 459 * Fatal error (KERNEL) 460 */ 461 #define PANIC(msg,label) \ 462 MSG(msg,a0,label); \ 463 CALL(panic) 464 465 /* 466 * Register mask defines, used to define both save 467 * and use register sets. 468 * 469 * NOTE: The bit order should HAVE BEEN maintained when saving 470 * registers on the stack: sp goes at the highest 471 * address, gp lower on the stack, etc etc 472 * BUT NOONE CARES ABOUT DEBUGGERS AT MIPS 473 */ 474 475 #define IM_EXC 0x80000000 476 #define IM_SP 0x40000000 477 #define IM_GP 0x20000000 478 #define IM_AT 0x10000000 479 #define IM_T12 0x08000000 480 # define IM_PV IM_T4 481 #define IM_RA 0x04000000 482 #define IM_T11 0x02000000 483 # define IM_AI IM_T3 484 #define IM_T10 0x01000000 485 #define IM_T9 0x00800000 486 #define IM_T8 0x00400000 487 #define IM_A5 0x00200000 488 #define IM_A4 0x00100000 489 #define IM_A3 0x00080000 490 #define IM_A2 0x00040000 491 #define IM_A1 0x00020000 492 #define IM_A0 0x00010000 493 #define IM_S6 0x00008000 494 #define IM_S5 0x00004000 495 #define IM_S4 0x00002000 496 #define IM_S3 0x00001000 497 #define IM_S2 0x00000800 498 #define IM_S1 0x00000400 499 #define IM_S0 0x00000200 500 #define IM_T7 0x00000100 501 #define IM_T6 0x00000080 502 #define IM_T5 0x00000040 503 #define IM_T4 0x00000020 504 #define IM_T3 0x00000010 505 #define IM_T2 0x00000008 506 #define IM_T1 0x00000004 507 #define IM_T0 0x00000002 508 #define IM_V0 0x00000001 509 510 #define FM_T15 0x40000000 511 #define FM_T14 0x20000000 512 #define FM_T13 0x10000000 513 #define FM_T12 0x08000000 514 #define FM_T11 0x04000000 515 #define FM_T10 0x02000000 516 #define FM_T9 0x01000000 517 #define FM_T8 0x00800000 518 #define FM_T7 0x00400000 519 #define FM_A5 0x00200000 520 #define FM_A4 0x00100000 521 #define FM_A3 0x00080000 522 #define FM_A2 0x00040000 523 #define FM_A1 0x00020000 524 #define FM_A0 0x00010000 525 #define FM_T6 0x00008000 526 #define FM_T5 0x00004000 527 #define FM_T4 0x00002000 528 #define FM_T3 0x00001000 529 #define FM_T2 0x00000800 530 #define FM_T1 0x00000400 531 #define FM_S7 0x00000200 532 #define FM_S6 0x00000100 533 #define FM_S5 0x00000080 534 #define FM_S4 0x00000040 535 #define FM_S3 0x00000020 536 #define FM_S2 0x00000010 537 #define FM_S1 0x00000008 538 #define FM_S0 0x00000004 539 #define FM_T0 0x00000002 540 #define FM_V1 FM_T0 541 #define FM_V0 0x00000001 542 543 /* 544 * PAL "function" codes (used as arguments to call_pal instructions). 545 * 546 * Those marked with "P" are privileged, and those marked with "U" 547 * are unprivileged. 548 */ 549 550 /* Common PAL function codes. */ 551 #define PAL_halt 0x0000 /* P */ 552 #define PAL_draina 0x0002 /* P */ 553 #define PAL_cserve 0x0009 /* P */ 554 #define PAL_swppal 0x000a /* P */ 555 #define PAL_bpt 0x0080 /* U */ 556 #define PAL_bugchk 0x0081 /* U */ 557 #define PAL_imb 0x0086 /* U */ 558 #define PAL_rdunique 0x009e /* U */ 559 #define PAL_wrunique 0x009f /* U */ 560 #define PAL_gentrap 0x00aa /* U */ 561 562 /* VMS PAL function codes. */ 563 #define PAL_VMS_ldqp 0x0003 /* P */ 564 #define PAL_VMS_stqp 0x0004 /* P */ 565 #define PAL_VMS_mtpr_fen 0x000c /* P */ 566 #define PAL_VMS_mtpr_ipir 0x000d /* P */ 567 #define PAL_VMS_mfpr_ipl 0x000e /* P */ 568 #define PAL_VMS_mtpr_ipl 0x000f /* P */ 569 #define PAL_VMS_mfpr_mces 0x0010 /* P */ 570 #define PAL_VMS_mtpr_mces 0x0011 /* P */ 571 #define PAL_VMS_mfpr_prbr 0x0013 /* P */ 572 #define PAL_VMS_mtpr_prbr 0x0014 /* P */ 573 #define PAL_VMS_mfpr_ptbr 0x0015 /* P */ 574 #define PAL_VMS_mtpr_scbb 0x0017 /* P */ 575 #define PAL_VMS_mtpr_sirr 0x0018 /* P */ 576 #define PAL_VMS_mtpr_tbia 0x001b /* P */ 577 #define PAL_VMS_mtpr_tbiap 0x001c /* P */ 578 #define PAL_VMS_mtpr_tbis 0x001d /* P */ 579 #define PAL_VMS_mfpr_usp 0x0022 /* P */ 580 #define PAL_VMS_mtpr_usp 0x0023 /* P */ 581 #define PAL_VMS_mfpr_vptb 0x0029 /* P */ 582 #define PAL_VMS_mfpr_whami 0x003f /* P */ 583 #define PAL_VMS_rei 0x0092 /* U */ 584 585 /* OSF/1 PAL function codes. */ 586 #define PAL_OSF1_rdmces 0x0010 /* P */ 587 #define PAL_OSF1_wrmces 0x0011 /* P */ 588 #define PAL_OSF1_wrfen 0x002b /* P */ 589 #define PAL_OSF1_wrvptptr 0x002d /* P */ 590 #define PAL_OSF1_swpctx 0x0030 /* P */ 591 #define PAL_OSF1_wrval 0x0031 /* P */ 592 #define PAL_OSF1_rdval 0x0032 /* P */ 593 #define PAL_OSF1_tbi 0x0033 /* P */ 594 #define PAL_OSF1_wrent 0x0034 /* P */ 595 #define PAL_OSF1_swpipl 0x0035 /* P */ 596 #define PAL_OSF1_rdps 0x0036 /* P */ 597 #define PAL_OSF1_wrkgp 0x0037 /* P */ 598 #define PAL_OSF1_wrusp 0x0038 /* P */ 599 #define PAL_OSF1_rdusp 0x003a /* P */ 600 #define PAL_OSF1_whami 0x003c /* P */ 601 #define PAL_OSF1_retsys 0x003d /* P */ 602 #define PAL_OSF1_rti 0x003f /* P */ 603 #define PAL_OSF1_callsys 0x0083 /* U */ 604 #define PAL_OSF1_imb 0x0086 /* U */ 605 606 607 /* 608 * System call glue. 609 */ 610 #define SYSCALLNUM(name) \ 611 ___CONCAT(SYS_,name) 612 613 #define CALLSYS_NOERROR(name) \ 614 ldiq v0, SYSCALLNUM(name); \ 615 call_pal PAL_OSF1_callsys 616 617 /* 618 * Load the global pointer. 619 */ 620 #define LDGP(reg) \ 621 ldgp gp, 0(reg) 622 623 /* 624 * WEAK_ALIAS: create a weak alias (ELF only). 625 */ 626 #ifdef __ELF__ 627 #define WEAK_ALIAS(alias,sym) \ 628 .weak alias; \ 629 alias = sym 630 #endif 631 632 /* 633 * Kernel RCS ID tag and copyright macros 634 */ 635 636 #ifdef _KERNEL 637 638 #define __KERNEL_SECTIONSTRING(_sec, _str) \ 639 .section _sec ; .asciz _str ; .text 640 641 #ifdef __ELF__ 642 643 #define __KERNEL_RCSID(_n, _s) __KERNEL_SECTIONSTRING(.ident, _s) 644 #define __KERNEL_COPYRIGHT(_n, _s) __KERNEL_SECTIONSTRING(.copyright, _s) 645 646 #else /* __ELF__ */ 647 648 #define __KERNEL_RCSID(_n, _s) __KERNEL_SECTIONSTRING(.text, _s) 649 #define __KERNEL_COPYRIGHT(_n, _s) __KERNEL_SECTIONSTRING(.text, _s) 650 651 #endif /* __ELF__ */ 652 653 #ifdef NO_KERNEL_RCSIDS 654 #undef __KERNEL_RCSID 655 #define __KERNEL_RCSID(_n, _s) /* nothing */ 656 #endif 657 658 #endif /* _KERNEL */ 659
Indexes created Thu Sep 25 16:09:42 GMT 2025