coregrind/m_libcsetjmp.c

   1
   2 /*--------------------------------------------------------------------*/
   3 /*--- A minimal setjmp/longjmp implementation.      m_libcsetjmp.c ---*/
   4 /*--------------------------------------------------------------------*/
   5
   6 /*
   7    This file is part of Valgrind, a dynamic binary instrumentation
   8    framework.
   9
  10    Copyright (C) 2010-2017 Mozilla Foundation
  11
  12    This program is free software; you can redistribute it and/or
  13    modify it under the terms of the GNU General Public License as
  14    published by the Free Software Foundation; either version 2 of the
  15    License, or (at your option) any later version.
  16
  17    This program is distributed in the hope that it will be useful, but
  18    WITHOUT ANY WARRANTY; without even the implied warranty of
  19    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20    General Public License for more details.
  21
  22    You should have received a copy of the GNU General Public License
  23    along with this program; if not, see <http://www.gnu.org/licenses/>.
  24
  25    The GNU General Public License is contained in the file COPYING.
  26 */
  27
  28 /* Contributed by Julian Seward <jseward@acm.org> */
  29
  30 /* This file must be compiled without link time optimisation, as otherwise
  31    the asm functions below become undefined references at link time for
  32    unclear reasons. */
  33
  34 #include "pub_core_basics.h"
  35 #include "pub_core_libcsetjmp.h"    /* self */
  36
  37 /* See include/pub_tool_libcsetjmp.h for background and rationale. */
  38
  39 /* The alternative implementations are for s390x-linux, ppc{32,64}-linux, and
  40    {amd64,x86}-{linux,darwin,solaris,freebsd}.  See #259977.  That leaves only
  41    arm-linux using the gcc builtins now.
  42 */
  43
  44 /* ------------ ppc32-linux ------------ */
  45
  46 #if defined(VGP_ppc32_linux)
  47
  48 __asm__(
  49 ".text"  "\n"
  50 ""       "\n"
  51 ".global VG_MINIMAL_SETJMP"  "\n"  // r3 = jmp_buf
  52 "VG_MINIMAL_SETJMP:"  "\n"
  53 "        stw     0, 0(3)"  "\n"
  54 "        stw     1, 4(3)"  "\n"
  55 "        stw     2, 8(3)"  "\n"
  56 "        stw     3, 12(3)"  "\n"
  57 "        stw     4, 16(3)"  "\n"
  58 "        stw     5, 20(3)"  "\n"
  59 "        stw     6, 24(3)"  "\n"
  60 "        stw     7, 28(3)"  "\n"
  61 "        stw     8, 32(3)"  "\n"
  62 "        stw     9, 36(3)"  "\n"
  63 "        stw     10, 40(3)"  "\n"
  64 "        stw     11, 44(3)"  "\n"
  65 "        stw     12, 48(3)"  "\n"
  66 "        stw     13, 52(3)"  "\n"
  67 "        stw     14, 56(3)"  "\n"
  68 "        stw     15, 60(3)"  "\n"
  69 "        stw     16, 64(3)"  "\n"
  70 "        stw     17, 68(3)"  "\n"
  71 "        stw     18, 72(3)"  "\n"
  72 "        stw     19, 76(3)"  "\n"
  73 "        stw     20, 80(3)"  "\n"
  74 "        stw     21, 84(3)"  "\n"
  75 "        stw     22, 88(3)"  "\n"
  76 "        stw     23, 92(3)"  "\n"
  77 "        stw     24, 96(3)"  "\n"
  78 "        stw     25, 100(3)"  "\n"
  79 "        stw     26, 104(3)"  "\n"
  80 "        stw     27, 108(3)"  "\n"
  81 "        stw     28, 112(3)"  "\n"
  82 "        stw     29, 116(3)"  "\n"
  83 "        stw     30, 120(3)"  "\n"
  84 "        stw     31, 124(3)"  "\n"
  85          // must use a caller-save register here as scratch, hence r4
  86 "        mflr    4"  "\n"
  87 "        stw     4, 128(3)"  "\n"
  88 "        mfcr    4"  "\n"
  89 "        stw     4, 132(3)"  "\n"
  90 "        li      3, 0"  "\n"
  91 "        blr"  "\n"
  92 ""       "\n"
  93
  94
  95 ".global VG_MINIMAL_LONGJMP"  "\n"
  96 "VG_MINIMAL_LONGJMP:"  "\n"    // r3 = jmp_buf
  97          // do r4 = 1
  98          // and park it in the restore slot for r3 (the ret reg)
  99 "        li      4, 1"  "\n"
 100 "        stw     4, 12(3)"  "\n"
 101          // restore everything except r3
 102          // then r3 last of all
 103          // then blr
 104 "        lwz     0, 128(3)"  "\n"
 105 "        mtlr    0"  "\n"
 106 "        lwz     0, 132(3)"  "\n"
 107 "        mtcr    0"  "\n"
 108 "        lwz     0, 0(3)"  "\n"
 109 "        lwz     1, 4(3)"  "\n"
 110 "        lwz     2, 8(3)"  "\n"
 111          // r3 is done at the end
 112 "        lwz     4, 16(3)"  "\n"
 113 "        lwz     5, 20(3)"  "\n"
 114 "        lwz     6, 24(3)"  "\n"
 115 "        lwz     7, 28(3)"  "\n"
 116 "        lwz     8, 32(3)"  "\n"
 117 "        lwz     9, 36(3)"  "\n"
 118 "        lwz     10, 40(3)"  "\n"
 119 "        lwz     11, 44(3)"  "\n"
 120 "        lwz     12, 48(3)"  "\n"
 121 "        lwz     13, 52(3)"  "\n"
 122 "        lwz     14, 56(3)"  "\n"
 123 "        lwz     15, 60(3)"  "\n"
 124 "        lwz     16, 64(3)"  "\n"
 125 "        lwz     17, 68(3)"  "\n"
 126 "        lwz     18, 72(3)"  "\n"
 127 "        lwz     19, 76(3)"  "\n"
 128 "        lwz     20, 80(3)"  "\n"
 129 "        lwz     21, 84(3)"  "\n"
 130 "        lwz     22, 88(3)"  "\n"
 131 "        lwz     23, 92(3)"  "\n"
 132 "        lwz     24, 96(3)"  "\n"
 133 "        lwz     25, 100(3)"  "\n"
 134 "        lwz     26, 104(3)"  "\n"
 135 "        lwz     27, 108(3)"  "\n"
 136 "        lwz     28, 112(3)"  "\n"
 137 "        lwz     29, 116(3)"  "\n"
 138 "        lwz     30, 120(3)"  "\n"
 139 "        lwz     31, 124(3)"  "\n"
 140 "        lwz     3, 12(3)"  "\n"
 141 "        blr"  "\n"
 142 ""       "\n"
 143
 144 ".previous"  "\n"
 145 );
 146
 147 #endif /* VGP_ppc32_linux */
 148
 149
 150 /* ------------ ppc64-linux ------------ */
 151
 152 #if defined(VGP_ppc64be_linux)
 153
 154 __asm__(
 155 ".section \".toc\",\"aw\""          "\n"
 156
 157 ".section \".text\""                "\n"
 158 ".align 2"                          "\n"
 159 ".p2align 4,,15"                    "\n"
 160 ".globl VG_MINIMAL_SETJMP"          "\n"
 161 ".section \".opd\",\"aw\""          "\n"
 162 ".align 3"                          "\n"
 163 "VG_MINIMAL_SETJMP:"                "\n"
 164 ".quad .L.VG_MINIMAL_SETJMP,.TOC.@tocbase,0"   "\n"
 165 ".previous"                         "\n"
 166
 167 ".type VG_MINIMAL_SETJMP, @function"   "\n"
 168 ".L.VG_MINIMAL_SETJMP:"   "\n"
 169 "        std     0, 0(3)"  "\n"
 170 "        std     1, 8(3)"  "\n"
 171 "        std     2, 16(3)"  "\n"
 172 "        std     3, 24(3)"  "\n"
 173 "        std     4, 32(3)"  "\n"
 174 "        std     5, 40(3)"  "\n"
 175 "        std     6, 48(3)"  "\n"
 176 "        std     7, 56(3)"  "\n"
 177 "        std     8, 64(3)"  "\n"
 178 "        std     9, 72(3)"  "\n"
 179 "        std     10, 80(3)"  "\n"
 180 "        std     11, 88(3)"  "\n"
 181 "        std     12, 96(3)"  "\n"
 182 "        std     13, 104(3)"  "\n"
 183 "        std     14, 112(3)"  "\n"
 184 "        std     15, 120(3)"  "\n"
 185 "        std     16, 128(3)"  "\n"
 186 "        std     17, 136(3)"  "\n"
 187 "        std     18, 144(3)"  "\n"
 188 "        std     19, 152(3)"  "\n"
 189 "        std     20, 160(3)"  "\n"
 190 "        std     21, 168(3)"  "\n"
 191 "        std     22, 176(3)"  "\n"
 192 "        std     23, 184(3)"  "\n"
 193 "        std     24, 192(3)"  "\n"
 194 "        std     25, 200(3)"  "\n"
 195 "        std     26, 208(3)"  "\n"
 196 "        std     27, 216(3)"  "\n"
 197 "        std     28, 224(3)"  "\n"
 198 "        std     29, 232(3)"  "\n"
 199 "        std     30, 240(3)"  "\n"
 200 "        std     31, 248(3)"  "\n"
 201          // must use a caller-save register here as scratch, hence r4
 202 "        mflr    4"  "\n"
 203 "        std     4, 256(3)"  "\n"
 204 "        mfcr    4"  "\n"
 205 "        std     4, 264(3)"  "\n"
 206 "        li      3, 0"  "\n"
 207 "        blr"  "\n"
 208 ""       "\n"
 209
 210
 211 ".globl VG_MINIMAL_LONGJMP"         "\n"
 212
 213 ".section \".opd\",\"aw\""          "\n"
 214 ".align 3"                          "\n"
 215 "VG_MINIMAL_LONGJMP:"               "\n"
 216 ".quad .L.VG_MINIMAL_LONGJMP,.TOC.@tocbase,0"   "\n"
 217 ".previous" "\n"
 218
 219 ".type   VG_MINIMAL_LONGJMP, @function"    "\n"
 220 ".L.VG_MINIMAL_LONGJMP:"            "\n"
 221          // do r4 = 1
 222          // and park it in the restore slot for r3 (the ret reg)
 223 "        li      4, 1"  "\n"
 224 "        std     4, 24(3)"  "\n"
 225          // restore everything except r3
 226          // then r3 last of all
 227          // then blr
 228 "        ld      0, 256(3)"  "\n"
 229 "        mtlr    0"  "\n"
 230 "        ld      0, 264(3)"  "\n"
 231 "        mtcr    0"  "\n"
 232 "        ld      0, 0(3)"  "\n"
 233 "        ld      1, 8(3)"  "\n"
 234 "        ld      2, 16(3)"  "\n"
 235          // r3 is done at the end
 236 "        ld      4, 32(3)"  "\n"
 237 "        ld      5, 40(3)"  "\n"
 238 "        ld      6, 48(3)"  "\n"
 239 "        ld      7, 56(3)"  "\n"
 240 "        ld      8, 64(3)"  "\n"
 241 "        ld      9, 72(3)"  "\n"
 242 "        ld      10, 80(3)"  "\n"
 243 "        ld      11, 88(3)"  "\n"
 244 "        ld      12, 96(3)"  "\n"
 245 "        ld      13, 104(3)"  "\n"
 246 "        ld      14, 112(3)"  "\n"
 247 "        ld      15, 120(3)"  "\n"
 248 "        ld      16, 128(3)"  "\n"
 249 "        ld      17, 136(3)"  "\n"
 250 "        ld      18, 144(3)"  "\n"
 251 "        ld      19, 152(3)"  "\n"
 252 "        ld      20, 160(3)"  "\n"
 253 "        ld      21, 168(3)"  "\n"
 254 "        ld      22, 176(3)"  "\n"
 255 "        ld      23, 184(3)"  "\n"
 256 "        ld      24, 192(3)"  "\n"
 257 "        ld      25, 200(3)"  "\n"
 258 "        ld      26, 208(3)"  "\n"
 259 "        ld      27, 216(3)"  "\n"
 260 "        ld      28, 224(3)"  "\n"
 261 "        ld      29, 232(3)"  "\n"
 262 "        ld      30, 240(3)"  "\n"
 263 "        ld      31, 248(3)"  "\n"
 264 "        ld      3, 24(3)"  "\n"
 265 "        blr"               "\n"
 266 ""       "\n"
 267
 268 ".previous"  "\n"
 269 );
 270
 271 #elif defined(VGP_ppc64le_linux)
 272 __asm__(
 273 ".section \".toc\",\"aw\""          "\n"
 274
 275 ".section \".text\""                "\n"
 276 ".align 2"                          "\n"
 277 ".p2align 4,,15"                    "\n"
 278 ".globl VG_MINIMAL_SETJMP"          "\n"
 279 ".type VG_MINIMAL_SETJMP,@function" "\n"
 280 "VG_MINIMAL_SETJMP:"                "\n"
 281 "       .localentry VG_MINIMAL_SETJMP, .-VG_MINIMAL_SETJMP" "\n"
 282 "        std     0, 0(3)"  "\n"
 283 "        std     1, 8(3)"  "\n"
 284 "        std     2, 16(3)"  "\n"
 285 "        std     3, 24(3)"  "\n"
 286 "        std     4, 32(3)"  "\n"
 287 "        std     5, 40(3)"  "\n"
 288 "        std     6, 48(3)"  "\n"
 289 "        std     7, 56(3)"  "\n"
 290 "        std     8, 64(3)"  "\n"
 291 "        std     9, 72(3)"  "\n"
 292 "        std     10, 80(3)"  "\n"
 293 "        std     11, 88(3)"  "\n"
 294 "        std     12, 96(3)"  "\n"
 295 "        std     13, 104(3)"  "\n"
 296 "        std     14, 112(3)"  "\n"
 297 "        std     15, 120(3)"  "\n"
 298 "        std     16, 128(3)"  "\n"
 299 "        std     17, 136(3)"  "\n"
 300 "        std     18, 144(3)"  "\n"
 301 "        std     19, 152(3)"  "\n"
 302 "        std     20, 160(3)"  "\n"
 303 "        std     21, 168(3)"  "\n"
 304 "        std     22, 176(3)"  "\n"
 305 "        std     23, 184(3)"  "\n"
 306 "        std     24, 192(3)"  "\n"
 307 "        std     25, 200(3)"  "\n"
 308 "        std     26, 208(3)"  "\n"
 309 "        std     27, 216(3)"  "\n"
 310 "        std     28, 224(3)"  "\n"
 311 "        std     29, 232(3)"  "\n"
 312 "        std     30, 240(3)"  "\n"
 313 "        std     31, 248(3)"  "\n"
 314 // must use a caller-save register here as scratch, hence r4
 315 "        mflr    4"  "\n"
 316 "        std     4, 256(3)"  "\n"
 317 "        mfcr    4"  "\n"
 318 "        std     4, 264(3)"  "\n"
 319 "        li      3, 0"  "\n"
 320 "        blr"  "\n"
 321 ""       "\n"
 322
 323
 324 ".globl VG_MINIMAL_LONGJMP"                "\n"
 325 ".type   VG_MINIMAL_LONGJMP, @function"    "\n"
 326 "VG_MINIMAL_LONGJMP:"                      "\n"
 327 "        .localentry VG_MINIMAL_LONGJMP, .-VG_MINIMAL_LONGJMP" "\n"
 328          // do r4 = 1
 329          // and park it in the restore slot for r3 (the ret reg)
 330 "        li      4, 1"  "\n"
 331 "        std     4, 24(3)"  "\n"
 332          // restore everything except r3
 333          // then r3 last of all
 334          // then blr
 335 "        ld      0, 256(3)"  "\n"
 336 "        mtlr    0"  "\n"
 337 "        ld      0, 264(3)"  "\n"
 338 "        mtcr    0"  "\n"
 339 "        ld      0, 0(3)"  "\n"
 340 "        ld      1, 8(3)"  "\n"
 341 "        ld      2, 16(3)"  "\n"
 342          // r3 is done at the end
 343 "        ld      4, 32(3)"  "\n"
 344 "        ld      5, 40(3)"  "\n"
 345 "        ld      6, 48(3)"  "\n"
 346 "        ld      7, 56(3)"  "\n"
 347 "        ld      8, 64(3)"  "\n"
 348 "        ld      9, 72(3)"  "\n"
 349 "        ld      10, 80(3)"  "\n"
 350 "        ld      11, 88(3)"  "\n"
 351 "        ld      12, 96(3)"  "\n"
 352 "        ld      13, 104(3)"  "\n"
 353 "        ld      14, 112(3)"  "\n"
 354 "        ld      15, 120(3)"  "\n"
 355 "        ld      16, 128(3)"  "\n"
 356 "        ld      17, 136(3)"  "\n"
 357 "        ld      18, 144(3)"  "\n"
 358 "        ld      19, 152(3)"  "\n"
 359 "        ld      20, 160(3)"  "\n"
 360 "        ld      21, 168(3)"  "\n"
 361 "        ld      22, 176(3)"  "\n"
 362 "        ld      23, 184(3)"  "\n"
 363 "        ld      24, 192(3)"  "\n"
 364 "        ld      25, 200(3)"  "\n"
 365 "        ld      26, 208(3)"  "\n"
 366 "        ld      27, 216(3)"  "\n"
 367 "        ld      28, 224(3)"  "\n"
 368 "        ld      29, 232(3)"  "\n"
 369 "        ld      30, 240(3)"  "\n"
 370 "        ld      31, 248(3)"  "\n"
 371 "        ld      3, 24(3)"  "\n"
 372 "        blr"               "\n"
 373 ""       "\n"
 374
 375 ".previous"  "\n"
 376 );
 377 #endif /* VGP_ppc64be_linux */
 378
 379
 380 /* -------- amd64-{linux,darwin,solaris,freebsd} -------- */
 381
 382 #if defined(VGP_amd64_linux) || defined(VGP_amd64_darwin) || \
 383     defined(VGP_amd64_solaris) || defined(VGP_amd64_freebsd)
 384
 385 __asm__(
 386 ".text"  "\n"
 387 ""       "\n"
 388
 389 #if defined(VGP_amd64_linux) || defined(VGP_amd64_solaris) || defined(VGP_amd64_freebsd)
 390 ".global VG_MINIMAL_SETJMP"  "\n"  // rdi = jmp_buf
 391 "VG_MINIMAL_SETJMP:"  "\n"
 392
 393 #elif defined(VGP_amd64_darwin)
 394 ".globl _VG_MINIMAL_SETJMP"  "\n"  // rdi = jmp_buf
 395 "_VG_MINIMAL_SETJMP:"  "\n"
 396
 397 #else
 398 #   error "Huh?"
 399 #endif
 400
 401 "        movq   %rax,   0(%rdi)"   "\n"
 402 "        movq   %rbx,   8(%rdi)"   "\n"
 403 "        movq   %rcx,  16(%rdi)"   "\n"
 404 "        movq   %rdx,  24(%rdi)"   "\n"
 405 "        movq   %rdi,  32(%rdi)"   "\n"
 406 "        movq   %rsi,  40(%rdi)"   "\n"
 407 "        movq   %rbp,  48(%rdi)"   "\n"
 408 "        movq   %rsp,  56(%rdi)"   "\n"
 409 "        movq   %r8,   64(%rdi)"   "\n"
 410 "        movq   %r9,   72(%rdi)"   "\n"
 411 "        movq   %r10,  80(%rdi)"   "\n"
 412 "        movq   %r11,  88(%rdi)"   "\n"
 413 "        movq   %r12,  96(%rdi)"   "\n"
 414 "        movq   %r13, 104(%rdi)"   "\n"
 415 "        movq   %r14, 112(%rdi)"   "\n"
 416 "        movq   %r15, 120(%rdi)"   "\n"
 417          // store the return address
 418 "        movq   0(%rsp), %rax"     "\n"
 419 "        movq   %rax, 128(%rdi)"   "\n"
 420          // and return zero
 421 "        movq   $0, %rax"          "\n"
 422 "        ret"                      "\n"
 423 ""       "\n"
 424
 425
 426 #if defined(VGP_amd64_linux) || defined(VGP_amd64_solaris) || defined(VGP_amd64_freebsd)
 427 ".global VG_MINIMAL_LONGJMP"  "\n"
 428 "VG_MINIMAL_LONGJMP:"  "\n"    // rdi = jmp_buf
 429
 430 #elif defined(VGP_amd64_darwin)
 431 ".globl _VG_MINIMAL_LONGJMP"  "\n"
 432 "_VG_MINIMAL_LONGJMP:"  "\n"    // rdi = jmp_buf
 433
 434 #else
 435 #   error "Huh?"
 436 #endif
 437          // skip restoring rax; it's pointless
 438 "        movq     8(%rdi),  %rbx"    "\n"
 439 "        movq    16(%rdi),  %rcx"    "\n"
 440 "        movq    24(%rdi),  %rdx"    "\n"
 441          // defer restoring rdi; we still need it
 442 "        movq    40(%rdi),  %rsi"    "\n"
 443 "        movq    48(%rdi),  %rbp"    "\n"
 444 "        movq    56(%rdi),  %rsp"    "\n"
 445 "        movq    64(%rdi),  %r8"     "\n"
 446 "        movq    72(%rdi),  %r9"     "\n"
 447 "        movq    80(%rdi),  %r10"    "\n"
 448 "        movq    88(%rdi),  %r11"    "\n"
 449 "        movq    96(%rdi),  %r12"    "\n"
 450 "        movq   104(%rdi),  %r13"    "\n"
 451 "        movq   112(%rdi),  %r14"    "\n"
 452 "        movq   120(%rdi),  %r15"    "\n"
 453          // restore the return address
 454 "        movq   128(%rdi), %rax"     "\n"
 455          // restore rdi; this is the last use
 456 "        movq   32(%rdi), %rdi"      "\n"
 457          // make %rsp look like we really did a return
 458 "        addq   $8, %rsp"            "\n"
 459          // continue at RA of original call.  Note: this is a
 460          // nasty trick.  We assume that %rax is nonzero, and so the
 461          // caller can differentiate this case from the normal _SETJMP
 462          // return case.  If the return address ever is zero, then
 463          // we're hosed; but that seems pretty unlikely given that it
 464          // would mean we'd be executing at the wraparound point of the
 465          // address space.
 466 "        jmp *%rax"                  "\n"
 467 ""       "\n"
 468
 469 #if !defined(VGP_amd64_darwin)
 470 ".previous"       "\n"
 471 #endif
 472 );
 473
 474 #endif /* VGP_amd64_linux || VGP_amd64_darwin || VGP_amd64_solaris || VGP_amd64_freebsd */
 475
 476
 477 /* -------- x86-{linux,darwin,solaris,freebsd} -------- */
 478
 479 #if defined(VGP_x86_linux) || defined(VGP_x86_darwin) || \
 480     defined(VGP_x86_solaris) || defined(VGP_x86_freebsd)
 481
 482 __asm__(
 483 ".text"  "\n"
 484 ""       "\n"
 485
 486 #if defined(VGP_x86_linux) || defined(VGP_x86_solaris) || defined(VGP_x86_freebsd)
 487 ".global VG_MINIMAL_SETJMP"  "\n"  // eax = jmp_buf
 488 "VG_MINIMAL_SETJMP:"  "\n"
 489
 490 #elif defined(VGP_x86_darwin)
 491 ".globl _VG_MINIMAL_SETJMP"  "\n"  // eax = jmp_buf
 492 "_VG_MINIMAL_SETJMP:"  "\n"
 493
 494 #else
 495 #   error "Huh?"
 496 #endif
 497
 498 "        movl   %eax,   0(%eax)"   "\n"
 499 "        movl   %ebx,   4(%eax)"   "\n"
 500 "        movl   %ecx,   8(%eax)"   "\n"
 501 "        movl   %edx,  12(%eax)"   "\n"
 502 "        movl   %edi,  16(%eax)"   "\n"
 503 "        movl   %esi,  20(%eax)"   "\n"
 504 "        movl   %ebp,  24(%eax)"   "\n"
 505 "        movl   %esp,  28(%eax)"   "\n"
 506          // store the return address
 507 "        movl   0(%esp), %ebx"     "\n"
 508 "        movl   %ebx, 32(%eax)"    "\n"
 509          // un-trash ebx (necessary?  i don't know)
 510 "        movl   4(%eax), %ebx"     "\n"
 511          // and return zero
 512 "        movl   $0, %eax"          "\n"
 513 "        ret"                      "\n"
 514 ""       "\n"
 515
 516
 517 #if defined(VGP_x86_linux) || defined(VGP_x86_solaris) || defined(VGP_x86_freebsd)
 518 ".global VG_MINIMAL_LONGJMP"  "\n"
 519 "VG_MINIMAL_LONGJMP:"  "\n"    // eax = jmp_buf
 520
 521 #elif defined(VGP_x86_darwin)
 522 ".globl _VG_MINIMAL_LONGJMP"  "\n"
 523 "_VG_MINIMAL_LONGJMP:"  "\n"    // eax = jmp_buf
 524
 525 #else
 526 #   error "Huh?"
 527 #endif
 528
 529          // skip restoring eax; it's pointless
 530 "        movl     4(%eax),  %ebx"    "\n"
 531 "        movl     8(%eax),  %ecx"    "\n"
 532 "        movl    12(%eax),  %edx"    "\n"
 533 "        movl    16(%eax),  %edi"    "\n"
 534 "        movl    20(%eax),  %esi"    "\n"
 535 "        movl    24(%eax),  %ebp"    "\n"
 536 "        movl    28(%eax),  %esp"    "\n"
 537          // restore the return address
 538 "        movl    32(%eax), %eax"     "\n"
 539          // make %esp look like we really did a return
 540 "        addl    $4, %esp"           "\n"
 541          // continue at RA of original call.  Same zero-vs-nonzero
 542          // trick/assumption as documented for the amd64-linux case.
 543 "        jmp *%eax"                  "\n"
 544 ""       "\n"
 545
 546 #if !defined(VGP_x86_darwin)
 547 ".previous"       "\n"
 548 #endif
 549 );
 550
 551 #endif /* VGP_x86_linux || VGP_x86_darwin || VGP_x86_solaris || VGP_x86_freebsd */
 552
 553 #if defined(VGP_mips32_linux)
 554
 555 __asm__(
 556 ".text                          \n\t"
 557 ".globl VG_MINIMAL_SETJMP;      \n\t"
 558 ".set push                      \n\t"
 559 ".set noreorder                 \n\t"
 560 "VG_MINIMAL_SETJMP:             \n\t"
 561 #if defined(__mips_hard_float)
 562 "   sdc1 $f20, 56($a0)          \n\t"
 563 "   sdc1 $f22, 64($a0)          \n\t"
 564 "   sdc1 $f24, 72($a0)          \n\t"
 565 "   sdc1 $f26, 80($a0)          \n\t"
 566 "   sdc1 $f28, 88($a0)          \n\t"
 567 "   sdc1 $f30, 96($a0)          \n\t"
 568 #endif
 569 "   sw   $gp,  44($a0)          \n\t"
 570 "   sw   $s0,   8($a0)          \n\t"
 571 "   sw   $s1,  12($a0)          \n\t"
 572 "   sw   $s2,  16($a0)          \n\t"
 573 "   sw   $s3,  20($a0)          \n\t"
 574 "   sw   $s4,  24($a0)          \n\t"
 575 "   sw   $s5,  28($a0)          \n\t"
 576 "   sw   $s6,  32($a0)          \n\t"
 577 "   sw   $s7,  36($a0)          \n\t"
 578 "   sw   $ra,   0($a0)          \n\t"
 579 "   sw   $sp,   4($a0)          \n\t"
 580 "   sw   $fp,  40($a0)          \n\t"
 581 "   jr   $ra                    \n\t"
 582 "   move $v0, $zero             \n\t"
 583 ".set pop                       \n\t"
 584 ".previous                      \n\t"
 585 "                               \n\t"
 586 ".text                          \n\t"
 587 ".globl VG_MINIMAL_LONGJMP;     \n\t"
 588 ".set push                      \n\t"
 589 ".set noreorder                 \n\t"
 590 "VG_MINIMAL_LONGJMP:            \n\t"
 591 #if defined(__mips_hard_float)
 592 "   ldc1    $f20, 56($a0)       \n\t"
 593 "   ldc1    $f22, 64($a0)       \n\t"
 594 "   ldc1    $f24, 72($a0)       \n\t"
 595 "   ldc1    $f26, 80($a0)       \n\t"
 596 "   ldc1    $f28, 88($a0)       \n\t"
 597 "   ldc1    $f30, 96($a0)       \n\t"
 598 #endif
 599 "   lw      $gp,  44($a0)       \n\t"
 600 "   lw      $s0,   8($a0)       \n\t"
 601 "   lw      $s1,  12($a0)       \n\t"
 602 "   lw      $s2,  16($a0)       \n\t"
 603 "   lw      $s3,  20($a0)       \n\t"
 604 "   lw      $s4,  24($a0)       \n\t"
 605 "   lw      $s5,  28($a0)       \n\t"
 606 "   lw      $s6,  32($a0)       \n\t"
 607 "   lw      $s7,  36($a0)       \n\t"
 608 "   lw      $ra,   0($a0)       \n\t"
 609 "   lw      $sp,   4($a0)       \n\t"
 610 "   bnez    $a1,   1f           \n\t"
 611 "   lw      $fp,  40($a0)       \n\t"
 612 "   addiu   $a1, $a1, 1         \n\t"
 613 "1:                             \n\t"
 614 "   jr      $ra                 \n\t"
 615 "   move    $v0, $a1            \n\t"
 616 ".set pop                       \n\t"
 617 ".previous                      \n\t"
 618 );
 619 #endif  /* VGP_mips32_linux */
 620
 621 #if defined(VGP_mips64_linux)
 622
 623 __asm__(
 624 ".text                          \n\t"
 625 ".globl VG_MINIMAL_SETJMP;      \n\t"
 626 ".set push                      \n\t"
 627 ".set noreorder                 \n\t"
 628 "VG_MINIMAL_SETJMP:             \n\t"
 629 #if defined(__mips_hard_float)
 630 "   sdc1    $f24, 104($a0)      \n\t"
 631 "   sdc1    $f25, 112($a0)      \n\t"
 632 "   sdc1    $f26, 120($a0)      \n\t"
 633 "   sdc1    $f27, 128($a0)      \n\t"
 634 "   sdc1    $f28, 136($a0)      \n\t"
 635 "   sdc1    $f29, 144($a0)      \n\t"
 636 "   sdc1    $f30, 152($a0)      \n\t"
 637 "   sdc1    $f31, 160($a0)      \n\t"
 638 #endif
 639 "   sd      $gp,   88($a0)      \n\t"
 640 "   sd      $s0,   16($a0)      \n\t"
 641 "   sd      $s1,   24($a0)      \n\t"
 642 "   sd      $s2,   32($a0)      \n\t"
 643 "   sd      $s3,   40($a0)      \n\t"
 644 "   sd      $s4,   48($a0)      \n\t"
 645 "   sd      $s5,   56($a0)      \n\t"
 646 "   sd      $s6,   64($a0)      \n\t"
 647 "   sd      $s7,   72($a0)      \n\t"
 648 "   sd      $ra,    0($a0)      \n\t"
 649 "   sd      $sp,    8($a0)      \n\t"
 650 "   sd      $fp,   80($a0)      \n\t"
 651 "   jr      $ra                 \n\t"
 652 "   move    $v0, $zero          \n\t"
 653 ".set pop                       \n\t"
 654 ".previous                      \n\t"
 655 "                               \n\t"
 656 ".text                          \n\t"
 657 ".globl VG_MINIMAL_LONGJMP;     \n\t"
 658 ".set push                      \n\t"
 659 ".set noreorder                 \n\t"
 660 "VG_MINIMAL_LONGJMP:            \n\t"
 661 #if defined(__mips_hard_float)
 662 "   ldc1    $f24, 104($a0)      \n\t"
 663 "   ldc1    $f25, 112($a0)      \n\t"
 664 "   ldc1    $f26, 120($a0)      \n\t"
 665 "   ldc1    $f27, 128($a0)      \n\t"
 666 "   ldc1    $f28, 136($a0)      \n\t"
 667 "   ldc1    $f29, 144($a0)      \n\t"
 668 "   ldc1    $f30, 152($a0)      \n\t"
 669 "   ldc1    $f31, 160($a0)      \n\t"
 670 #endif
 671 "   ld      $gp,   88($a0)      \n\t"
 672 "   ld      $s0,   16($a0)      \n\t"
 673 "   ld      $s1,   24($a0)      \n\t"
 674 "   ld      $s2,   32($a0)      \n\t"
 675 "   ld      $s3,   40($a0)      \n\t"
 676 "   ld      $s4,   48($a0)      \n\t"
 677 "   ld      $s5,   56($a0)      \n\t"
 678 "   ld      $s6,   64($a0)      \n\t"
 679 "   ld      $s7,   72($a0)      \n\t"
 680 "   ld      $ra,    0($a0)      \n\t"
 681 "   ld      $sp,    8($a0)      \n\t"
 682 "   bnez    $a1, 1f             \n\t"
 683 "   ld      $fp,   80($a0)      \n\t"
 684 "   daddiu  $a1, $a1, 1         \n\t"
 685 "1:                             \n\t"
 686 "   jr      $ra                 \n\t"
 687 "   move    $v0, $a1            \n\t"
 688 ".set pop                       \n\t"
 689 ".previous                      \n\t"
 690 );
 691 #endif  /* VGP_mips64_linux */
 692
 693 #if defined(VGP_nanomips_linux)
 694 __asm__(
 695 ".text                          \n\t"
 696 ".globl VG_MINIMAL_SETJMP;      \n\t"
 697 ".set push                      \n\t"
 698 ".set noreorder                 \n\t"
 699 "VG_MINIMAL_SETJMP:             \n\t"
 700 "   sw     $s0,   0($a0)        \n\t"
 701 "   sw     $s1,   4($a0)        \n\t"
 702 "   sw     $s2,   8($a0)        \n\t"
 703 "   sw     $s3,  12($a0)        \n\t"
 704 "   sw     $s4,  16($a0)        \n\t"
 705 "   sw     $s5,  20($a0)        \n\t"
 706 "   sw     $s6,  24($a0)        \n\t"
 707 "   sw     $s7,  28($a0)        \n\t"
 708 "   sw     $gp,  32($a0)        \n\t"
 709 "   sw     $sp,  36($a0)        \n\t"
 710 "   sw     $fp,  40($a0)        \n\t"
 711 "   sw     $ra,  44($a0)        \n\t"
 712 "   move   $a0,  $zero          \n\t"
 713 "   jrc    $ra                  \n\t"
 714 ".set pop                       \n\t"
 715 ".previous                      \n\t"
 716 "                               \n\t"
 717 ".text                          \n\t"
 718 ".globl VG_MINIMAL_LONGJMP;     \n\t"
 719 ".set push                      \n\t"
 720 ".set noreorder                 \n\t"
 721 "VG_MINIMAL_LONGJMP:            \n\t"
 722 "   lw     $s0,   0($a0)        \n\t"
 723 "   lw     $s1,   4($a0)        \n\t"
 724 "   lw     $s2,   8($a0)        \n\t"
 725 "   lw     $s3,  12($a0)        \n\t"
 726 "   lw     $s4,  16($a0)        \n\t"
 727 "   lw     $s5,  20($a0)        \n\t"
 728 "   lw     $s6,  24($a0)        \n\t"
 729 "   lw     $s7,  28($a0)        \n\t"
 730 "   lw     $gp,  32($a0)        \n\t"
 731 "   lw     $sp,  36($a0)        \n\t"
 732 "   lw     $fp,  40($a0)        \n\t"
 733 "   lw     $ra,  44($a0)        \n\t"
 734 "   bnezc  $a1,   1f            \n\t"
 735 "   addiu  $a1, $a1, 1          \n\t"
 736 "1:                             \n\t"
 737 "   move   $a0, $a1             \n\t"
 738 "   jrc    $ra                  \n\t"
 739 ".set pop                       \n\t"
 740 ".previous                      \n\t"
 741 );
 742 #endif  /* VGP_nanomips_linux */
 743
 744 /* ------------ s390x-linux ------------ */
 745
 746 #if defined(VGP_s390x_linux)
 747 __asm__(
 748 ".text"                                "\n"
 749 ".align 4"                             "\n"
 750 ".globl VG_MINIMAL_SETJMP"             "\n"
 751 ".type VG_MINIMAL_SETJMP, @function"   "\n"
 752 "VG_MINIMAL_SETJMP:"                   "\n"
 753 "        stmg    6,15,0(2)"            "\n"
 754 "        std     8,80(2)"              "\n"
 755 "        std     9,88(2)"              "\n"
 756 "        std     10,96(2)"             "\n"
 757 "        std     11,104(2)"            "\n"
 758 "        std     12,112(2)"            "\n"
 759 "        std     13,120(2)"            "\n"
 760 "        std     14,128(2)"            "\n"
 761 "        std     15,136(2)"            "\n"
 762 // return zero
 763 "        lghi    2,0"                  "\n"
 764 "        br      14"                   "\n"
 765
 766 ".align 4"                             "\n"
 767 ".globl VG_MINIMAL_LONGJMP"            "\n"
 768 ".type VG_MINIMAL_LONGJMP, @function"  "\n"
 769 "VG_MINIMAL_LONGJMP:"                  "\n"
 770 "        lmg     6,15,0(2)"            "\n"
 771 "        ld      8,80(2)"              "\n"
 772 "        ld      9,88(2)"              "\n"
 773 "        ld      10,96(2)"             "\n"
 774 "        ld      11,104(2)"            "\n"
 775 "        ld      12,112(2)"            "\n"
 776 "        ld      13,120(2)"            "\n"
 777 "        ld      14,128(2)"            "\n"
 778 "        ld      15,136(2)"            "\n"
 779 // return the argument (nonzero)
 780 "        br      14"                   "\n"
 781 );
 782 #endif /* VGP_s390x_linux */
 783
 784 #if defined(__clang__) && defined(VGP_arm64_linux)
 785
 786 // __builtin_setjmp is not implemented by the standard C library
 787 // used on Android in current llvm-based toolchains as of NDK r19.
 788 //
 789 // Here is a custom implementation of Valgrind's "minimal" setjmp
 790 // interface. Per the comment at the top of this file, we only need
 791 // to save integer registers.
 792 //
 793 // Per the Procedure Call Standard for the ARM 64-bit Architecture
 794 // document,
 795 // http://infocenter.arm.com/help/topic/com.arm.doc.ihi0055b/IHI0055B_aapcs64.pdf
 796 // Section 5.1.1. General-purpose registers:
 797 // >
 798 // > A subroutine invocation must preserve the contents of the
 799 // > registers r19-r29 and SP."
 800 //
 801 // We also need to save and restore r30, the link register, i.e.
 802 // the default destination that a 'ret' instruction branches to.
 803 //
 804 // Note that this document is phrased in terms of 'r' registers
 805 // (e.g. "r30") because it aims to be agnostic as to A64 vs A32
 806 // instruction sets, but here we are targeting the A64 instruction
 807 // set, so we are dealing with 'x' registers.
 808
 809
 810
 811 __attribute__((returns_twice))
 812 UWord VG_MINIMAL_SETJMP(VG_MINIMAL_JMP_BUF(_env))
 813 {
 814    asm volatile(
 815                  // x9 is the first of the regular temporary registers
 816                  // per the above-mentioned Procedule Call Standard document.
 817                  // Use it as temporary to hold the value of SP, since str does
 818                  // not accept SP as operand.
 819       "  mov x9, sp                     \n"
 820       // Store the general-purpose registers that we need to save
 821       // per the above discussion.
 822       // Note that x30 is the link register.
 823       "  stp x19, x20, [%[_env], 0]     \n"
 824       "  stp x21, x22, [%[_env], 0x10]  \n"
 825       "  stp x23, x24, [%[_env], 0x20]  \n"
 826       "  stp x25, x26, [%[_env], 0x30]  \n"
 827       "  stp x27, x28, [%[_env], 0x40]  \n"
 828       "  stp x29, x30, [%[_env], 0x50]  \n"
 829       // Store the value of SP.
 830       "  str x9,       [%[_env], 0x60]  \n"
 831       :
 832       // No outputs
 833       :
 834       // Inputs
 835       [_env]"r"(_env)
 836       :
 837       // Clobbers.
 838       // We have used x9 as a temporary
 839       "x9",
 840       // We have written to memory locations
 841       "memory");
 842
 843           // Direct invokation of setjmp always returns 0.
 844           // The pseudo returning of the value 1 as a return from longjmp
 845           // is implemented in longjmp.
 846    return 0;
 847 }
 848
 849 __attribute__((noreturn))
 850 void VG_MINIMAL_LONGJMP(VG_MINIMAL_JMP_BUF(_env))
 851 {
 852    asm volatile(
 853                  // Loads to match the stores in the above setjmp implementation.
 854       "  ldp x19, x20, [%[_env], 0]     \n"
 855       "  ldp x21, x22, [%[_env], 0x10]  \n"
 856       "  ldp x23, x24, [%[_env], 0x20]  \n"
 857       "  ldp x25, x26, [%[_env], 0x30]  \n"
 858       "  ldp x27, x28, [%[_env], 0x40]  \n"
 859       "  ldp x29, x30, [%[_env], 0x50]  \n"
 860       "  ldr x9,       [%[_env], 0x60]  \n"
 861       "  mov sp, x9                     \n"
 862       // return as setjmp for the second time, returning 1.
 863       // Since we have loaded the link register x30 from the saved buffer
 864       // that was set by the above setjmp implementation, the 'ret' instruction
 865       // here is going to return to where setjmp was called.
 866       // Per the setjmp/longjmp contract, that pseudo second returning
 867       // of setjmp should return the value 1.
 868       // x0 is holds the integer return value.
 869       "  mov x0, 1                      \n"
 870       "  ret                            \n"
 871       :
 872       // No outputs
 873       :
 874       // Inputs
 875       [_env]"r"(_env)
 876       :
 877       // Clobbers.
 878       // We have used x9 as a temporary
 879       "x9");
 880
 881           // This statement is unreachable because the above asm statement
 882           // unconditionally does a 'ret' instruction. The purpose of this
 883           // statement is to silence clang warnings about this function returning
 884           // while having the 'noreturn' attribute.
 885    __builtin_unreachable();
 886 }
 887
 888 #endif
 889
 890 #if defined(VGP_arm64_freebsd)
 891
 892 __asm__(
 893    ".text\n"
 894
 895    ".globl VG_MINIMAL_SETJMP"  "\n"
 896    "VG_MINIMAL_SETJMP:"  "\n" // x0 = jmp_buf
 897    "        mov             x1, sp\n" /* can't STP from sp */
 898    "        stp             x19, x20,       [x0, #0x00]\n"
 899    "        stp             x21, x22,       [x0, #0x10]\n"
 900    "        stp             x23, x24,       [x0, #0x20]\n"
 901    "        stp             x25, x26,       [x0, #0x30]\n"
 902    "        stp             x27, x28,       [x0, #0x40]\n"
 903    "        stp             x29, x30,       [x0, #0x50]\n"
 904    "        stp             x1, xzr,        [x0, #0x60]\n"
 905    "        stp             d8, d9,         [x0, #0x70]\n"
 906    "        stp             d10, d11,       [x0, #0x80]\n"
 907    "        stp             d12, d13,       [x0, #0x90]\n"
 908    "        stp             d14, d15,       [x0, #0xA0]\n"
 909    "        mov             x0, #0\n" // return 0 on the first return
 910    "        ret\n"
 911    ".previous\n"
 912
 913    ".globl VG_MINIMAL_LONGJMP"  "\n"
 914    "      VG_MINIMAL_LONGJMP:"  "\n" // x0 = jmp_buf
 915    "        ldp             x19, x20,       [x0, #0x00]\n"
 916    "        ldp             x21, x22,       [x0, #0x10]\n"
 917    "        ldp             x23, x24,       [x0, #0x20]\n"
 918    "        ldp             x25, x26,       [x0, #0x30]\n"
 919    "        ldp             x27, x28,       [x0, #0x40]\n"
 920    "        ldp             x29, x30,       [x0, #0x50]\n"
 921    "        ldp             x1, xzr,        [x0, #0x60]\n"
 922    "        ldp             d8, d9,         [x0, #0x70]\n"
 923    "        ldp             d10, d11,       [x0, #0x80]\n"
 924    "        ldp             d12, d13,       [x0, #0x90]\n"
 925    "        ldp             d14, d15,       [x0, #0xA0]\n"
 926    "        mov             sp, x1\n"
 927    "        mov             x0, #1\n" // return non-zero on the second return
 928    "        br              lr\n"
 929    ".previous\n"
 930    );
 931
 932 #endif
 933
 934 /*--------------------------------------------------------------------*/
 935 /*--- end                                                          ---*/
 936 /*--------------------------------------------------------------------*/