asm.h revision 1.6
1 /* $NetBSD: asm.h,v 1.6 1996/09/15 22:42:29 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 * Debuggers need symbol table information to be able to properly 135 * decode a stack trace. The minimum that should be provided is: 136 * 137 * name: 138 * .proc name,numargs 139 * 140 * where "name" is the function's name; 141 * "numargs" how many arguments it expects. For varargs 142 * procedures this should be a negative number, 143 * indicating the minimum required number of 144 * arguments (which is at least 1); 145 * 146 * NESTED functions (functions that call other functions) should define 147 * how they handle their stack frame in a .frame directive: 148 * 149 * .frame framesize, pc_reg, i_mask, f_mask 150 * 151 * where "framesize" is the size of the frame for this function, in bytes. 152 * That is: 153 * new_sp + framesize == old_sp 154 * Framesizes should be rounded to a cacheline size. 155 * Note that old_sp plays the role of a conventional 156 * "frame pointer"; 157 * "pc_reg" is either a register which preserves the caller's PC 158 * or 'std', if std the saved PC should be stored at 159 * old_sp-8 160 * "i_mask" is a bitmask that indicates which of the integer 161 * registers are saved. See the M_xx defines at the 162 * end for the encoding of this 32bit value. 163 * "f_mask" is the same, for floating point registers. 164 * 165 * Note that registers should be saved starting at "old_sp-8", where the 166 * return address should be stored. Other registers follow at -16-24-32.. 167 * starting from register 0 (if saved) and up. Then float registers (ifany) 168 * are saved. 169 * 170 * If you need to alias a leaf function, or to provide multiple entry points 171 * use the LEAF() macro for the main entry point and XLEAF() for the other 172 * additional/alternate entry points. 173 * "XLEAF"s must be nested within a "LEAF" and a ".end". 174 * Similar rules for nested routines, e.g. use NESTED/XNESTED 175 * Symbols that should not be exported can be declared with the STATIC_xxx 176 * macros. 177 * 178 * All functions must be terminated by the END macro 179 * 180 * It is conceivable, although currently at the limits of compiler 181 * technology, that while performing inter-procedural optimizations 182 * the compiler/linker be able to avoid unnecessary register spills 183 * if told about the register usage of LEAF procedures (and by transitive 184 * closure of NESTED procedures as well). Assembly code can help 185 * this process using the .reguse directive: 186 * 187 * .reguse i_mask, f_mask 188 * 189 * where the register masks are built as above or-ing M_xx defines. 190 * 191 * 192 * All symbols are internal unless EXPORTed. Symbols that are IMPORTed 193 * must be appropriately described to the debugger. 194 * 195 */ 196 197 /* 198 * MCOUNT 199 */ 200 201 #ifndef PROF 202 #define MCOUNT /* nothing */ 203 #else 204 #define MCOUNT \ 205 .set noat; \ 206 jsr at_reg,_mcount; \ 207 .set at 208 #endif 209 210 /* 211 * LEAF 212 * Declare a global leaf function. 213 * A leaf function does not call other functions AND does not 214 * use any register that is callee-saved AND does not modify 215 * the stack pointer. 216 */ 217 #define LEAF(_name_,_n_args_) \ 218 .globl _name_; \ 219 .ent _name_ 0; \ 220 _name_:; \ 221 .frame sp,0,ra; \ 222 MCOUNT 223 /* should have been 224 .proc _name_,_n_args_; \ 225 .frame 0,ra,0,0 226 */ 227 228 #define LEAF_NOPROFILE(_name_,_n_args_) \ 229 .globl _name_; \ 230 .ent _name_ 0; \ 231 _name_:; \ 232 .frame sp,0,ra 233 /* should have been 234 .proc _name_,_n_args_; \ 235 .frame 0,ra,0,0 236 */ 237 238 /* 239 * STATIC_LEAF 240 * Declare a local leaf function. 241 */ 242 #define STATIC_LEAF(_name_,_n_args_) \ 243 .ent _name_ 0; \ 244 _name_:; \ 245 .frame sp,0,ra; \ 246 MCOUNT 247 /* should have been 248 .proc _name_,_n_args_; \ 249 .frame 0,ra,0,0 250 */ 251 /* 252 * XLEAF 253 * Global alias for a leaf function, or alternate entry point 254 */ 255 #define XLEAF(_name_,_n_args_) \ 256 .globl _name_; \ 257 .aent _name_ 0; \ 258 _name_: 259 /* should have been 260 .aproc _name_,_n_args_; 261 */ 262 263 /* 264 * STATIC_XLEAF 265 * Local alias for a leaf function, or alternate entry point 266 */ 267 #define STATIC_XLEAF(_name_,_n_args_) \ 268 .aent _name_ 0; \ 269 _name_: 270 /* should have been 271 .aproc _name_,_n_args_; 272 */ 273 274 /* 275 * NESTED 276 * Declare a (global) nested function 277 * A nested function calls other functions and needs 278 * therefore stack space to save/restore registers. 279 */ 280 #define NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 281 .globl _name_; \ 282 .ent _name_ 0; \ 283 _name_:; \ 284 .frame sp,_framesize_,_pc_reg_; \ 285 .livereg _i_mask_,_f_mask_; \ 286 MCOUNT 287 /* should have been 288 .proc _name_,_n_args_; \ 289 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 290 */ 291 292 #define NESTED_NOPROFILE(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 293 .globl _name_; \ 294 .ent _name_ 0; \ 295 _name_:; \ 296 .frame sp,_framesize_,_pc_reg_; \ 297 .livereg _i_mask_,_f_mask_ 298 /* should have been 299 .proc _name_,_n_args_; \ 300 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 301 */ 302 303 /* 304 * STATIC_NESTED 305 * Declare a local nested function. 306 */ 307 #define STATIC_NESTED(_name_, _n_args_, _framesize_, _pc_reg_, _i_mask_, _f_mask_ ) \ 308 .ent _name_ 0; \ 309 _name_:; \ 310 .frame sp,_framesize_,_pc_reg_; \ 311 .livereg _i_mask_,_f_mask_; \ 312 MCOUNT 313 /* should have been 314 .proc _name_,_n_args_; \ 315 .frame _framesize_, _pc_reg_, _i_mask_, _f_mask_ 316 */ 317 318 /* 319 * XNESTED 320 * Same as XLEAF, for a nested function. 321 */ 322 #define XNESTED(_name_,_n_args_) \ 323 .globl _name_; \ 324 .aent _name_ 0; \ 325 _name_: 326 /* should have been 327 .aproc _name_,_n_args_; 328 */ 329 330 331 /* 332 * STATIC_XNESTED 333 * Same as STATIC_XLEAF, for a nested function. 334 */ 335 #define STATIC_XNESTED(_name_,_n_args_) \ 336 .aent _name_ 0; \ 337 _name_: 338 /* should have been 339 .aproc _name_,_n_args_; 340 */ 341 342 343 /* 344 * END 345 * Function delimiter 346 */ 347 #define END(_name_) \ 348 .end _name_ 349 350 351 /* 352 * CALL 353 * Function invocation 354 */ 355 #define CALL(_name_) \ 356 jsr ra,_name_; \ 357 ldgp gp,0(ra) 358 /* but this would cover longer jumps 359 br ra,.+4; \ 360 bsr ra,_name_ 361 */ 362 363 364 /* 365 * RET 366 * Return from function 367 */ 368 #define RET \ 369 ret zero,(ra),1 370 371 372 /* 373 * EXPORT 374 * Export a symbol 375 */ 376 #define EXPORT(_name_) \ 377 .globl _name_; \ 378 _name_: 379 380 381 /* 382 * IMPORT 383 * Make an external name visible, typecheck the size 384 */ 385 #define IMPORT(_name_, _size_) \ 386 .extern _name_,_size_ 387 388 389 /* 390 * ABS 391 * Define an absolute symbol 392 */ 393 #define ABS(_name_, _value_) \ 394 .globl _name_; \ 395 _name_ = _value_ 396 397 398 /* 399 * BSS 400 * Allocate un-initialized space for a global symbol 401 */ 402 #define BSS(_name_,_numbytes_) \ 403 .comm _name_,_numbytes_ 404 405 /* 406 * VECTOR 407 * Make an exception entry point look like a called function, 408 * to make it digestible to the debugger (KERNEL only) 409 */ 410 #define VECTOR(_name_, _i_mask_) \ 411 .globl _name_; \ 412 .ent _name_ 0; \ 413 _name_:; \ 414 .mask _i_mask_|IM_EXC,0; \ 415 .frame sp,MSS_SIZE,ra; 416 /* .livereg _i_mask_|IM_EXC,0 417 /* should have been 418 .proc _name_,1; \ 419 .frame MSS_SIZE,$31,_i_mask_,0; \ 420 */ 421 422 /* 423 * MSG 424 * Allocate space for a message (a read-only ascii string) 425 */ 426 #define ASCIZ .asciz 427 #define MSG(msg,reg,label) \ 428 lda reg, label; \ 429 .data; \ 430 label: ASCIZ msg; \ 431 .text; 432 433 /* 434 * PRINTF 435 * Print a message 436 */ 437 #define PRINTF(msg,label) \ 438 MSG(msg,a0,label); \ 439 CALL(printf) 440 441 /* 442 * PANIC 443 * Fatal error (KERNEL) 444 */ 445 #define PANIC(msg,label) \ 446 MSG(msg,a0,label); \ 447 CALL(panic) 448 449 /* 450 * Register mask defines, used to define both save 451 * and use register sets. 452 * 453 * NOTE: The bit order should HAVE BEEN maintained when saving 454 * registers on the stack: sp goes at the highest 455 * address, gp lower on the stack, etc etc 456 * BUT NOONE CARES ABOUT DEBUGGERS AT MIPS 457 */ 458 459 #define IM_EXC 0x80000000 460 #define IM_SP 0x40000000 461 #define IM_GP 0x20000000 462 #define IM_AT 0x10000000 463 #define IM_T12 0x08000000 464 # define IM_PV IM_T4 465 #define IM_RA 0x04000000 466 #define IM_T11 0x02000000 467 # define IM_AI IM_T3 468 #define IM_T10 0x01000000 469 #define IM_T9 0x00800000 470 #define IM_T8 0x00400000 471 #define IM_A5 0x00200000 472 #define IM_A4 0x00100000 473 #define IM_A3 0x00080000 474 #define IM_A2 0x00040000 475 #define IM_A1 0x00020000 476 #define IM_A0 0x00010000 477 #define IM_S6 0x00008000 478 #define IM_S5 0x00004000 479 #define IM_S4 0x00002000 480 #define IM_S3 0x00001000 481 #define IM_S2 0x00000800 482 #define IM_S1 0x00000400 483 #define IM_S0 0x00000200 484 #define IM_T7 0x00000100 485 #define IM_T6 0x00000080 486 #define IM_T5 0x00000040 487 #define IM_T4 0x00000020 488 #define IM_T3 0x00000010 489 #define IM_T2 0x00000008 490 #define IM_T1 0x00000004 491 #define IM_T0 0x00000002 492 #define IM_V0 0x00000001 493 494 #define FM_T15 0x40000000 495 #define FM_T14 0x20000000 496 #define FM_T13 0x10000000 497 #define FM_T12 0x08000000 498 #define FM_T11 0x04000000 499 #define FM_T10 0x02000000 500 #define FM_T9 0x01000000 501 #define FM_T8 0x00800000 502 #define FM_T7 0x00400000 503 #define FM_A5 0x00200000 504 #define FM_A4 0x00100000 505 #define FM_A3 0x00080000 506 #define FM_A2 0x00040000 507 #define FM_A1 0x00020000 508 #define FM_A0 0x00010000 509 #define FM_T6 0x00008000 510 #define FM_T5 0x00004000 511 #define FM_T4 0x00002000 512 #define FM_T3 0x00001000 513 #define FM_T2 0x00000800 514 #define FM_T1 0x00000400 515 #define FM_S7 0x00000200 516 #define FM_S6 0x00000100 517 #define FM_S5 0x00000080 518 #define FM_S4 0x00000040 519 #define FM_S3 0x00000020 520 #define FM_S2 0x00000010 521 #define FM_S1 0x00000008 522 #define FM_S0 0x00000004 523 #define FM_T0 0x00000002 524 #define FM_V1 FM_T0 525 #define FM_V0 0x00000001 526 527 /* 528 * PAL "function" codes (used as arguments to call_pal instructions). 529 * 530 * Those marked with "P" are privileged, and those marked with "U" 531 * are unprivileged. 532 */ 533 534 /* Common PAL function codes. */ 535 #define PAL_halt 0x0000 /* P */ 536 #define PAL_draina 0x0002 /* P */ 537 #define PAL_cserve 0x0009 /* P */ 538 #define PAL_swppal 0x000a /* P */ 539 #define PAL_bpt 0x0080 /* U */ 540 #define PAL_bugchk 0x0081 /* U */ 541 #define PAL_imb 0x0086 /* U */ 542 #define PAL_rdunique 0x009e /* U */ 543 #define PAL_wrunique 0x009f /* U */ 544 #define PAL_gentrap 0x00aa /* U */ 545 546 /* VMS PAL function codes. */ 547 #define PAL_VMS_ldqp 0x0003 /* P */ 548 #define PAL_VMS_stqp 0x0004 /* P */ 549 #define PAL_VMS_mtpr_fen 0x000c /* P */ 550 #define PAL_VMS_mtpr_ipir 0x000d /* P */ 551 #define PAL_VMS_mfpr_ipl 0x000e /* P */ 552 #define PAL_VMS_mtpr_ipl 0x000f /* P */ 553 #define PAL_VMS_mfpr_mces 0x0010 /* P */ 554 #define PAL_VMS_mtpr_mces 0x0011 /* P */ 555 #define PAL_VMS_mfpr_prbr 0x0013 /* P */ 556 #define PAL_VMS_mtpr_prbr 0x0014 /* P */ 557 #define PAL_VMS_mfpr_ptbr 0x0015 /* P */ 558 #define PAL_VMS_mtpr_scbb 0x0017 /* P */ 559 #define PAL_VMS_mtpr_sirr 0x0018 /* P */ 560 #define PAL_VMS_mtpr_tbia 0x001b /* P */ 561 #define PAL_VMS_mtpr_tbiap 0x001c /* P */ 562 #define PAL_VMS_mtpr_tbis 0x001d /* P */ 563 #define PAL_VMS_mfpr_usp 0x0022 /* P */ 564 #define PAL_VMS_mtpr_usp 0x0023 /* P */ 565 #define PAL_VMS_mfpr_vptb 0x0029 /* P */ 566 #define PAL_VMS_mfpr_whami 0x003f /* P */ 567 #define PAL_VMS_rei 0x0092 /* U */ 568 569 /* OSF/1 PAL function codes. */ 570 #define PAL_OSF1_rdmces 0x0010 /* P */ 571 #define PAL_OSF1_wrmces 0x0011 /* P */ 572 #define PAL_OSF1_wrfen 0x002b /* P */ 573 #define PAL_OSF1_wrvptptr 0x002d /* P */ 574 #define PAL_OSF1_swpctx 0x0030 /* P */ 575 #define PAL_OSF1_wrval 0x0031 /* P */ 576 #define PAL_OSF1_rdval 0x0032 /* P */ 577 #define PAL_OSF1_tbi 0x0033 /* P */ 578 #define PAL_OSF1_wrent 0x0034 /* P */ 579 #define PAL_OSF1_swpipl 0x0035 /* P */ 580 #define PAL_OSF1_rdps 0x0036 /* P */ 581 #define PAL_OSF1_wrkgp 0x0037 /* P */ 582 #define PAL_OSF1_wrusp 0x0038 /* P */ 583 #define PAL_OSF1_rdusp 0x003a /* P */ 584 #define PAL_OSF1_whami 0x003c /* P */ 585 #define PAL_OSF1_retsys 0x003d /* P */ 586 #define PAL_OSF1_rti 0x003f /* P */ 587 #define PAL_OSF1_callsys 0x0083 /* U */ 588 #define PAL_OSF1_imb 0x0086 /* U */ 589 590 /* 591 * Defintions to make things portable between gcc and OSF/1 cc. 592 */ 593 #define SETGP(pv) ldgp gp,0(pv) 594 595 #define MF_FPCR(x) mf_fpcr x 596 #define MT_FPCR(x) mt_fpcr x 597 #define JMP(loc) jmp zero,loc 598 #define CONST(c,reg) ldiq reg, c 599 600
Indexes created Fri Sep 26 08:10:20 GMT 2025