breakpad_getcontext.S
1 // Copyright 2012 Google LLC 2 // 3 // Redistribution and use in source and binary forms, with or without 4 // modification, are permitted provided that the following conditions are 5 // met: 6 // 7 // * Redistributions of source code must retain the above copyright 8 // notice, this list of conditions and the following disclaimer. 9 // * Redistributions in binary form must reproduce the above 10 // copyright notice, this list of conditions and the following disclaimer 11 // in the documentation and/or other materials provided with the 12 // distribution. 13 // * Neither the name of Google LLC nor the names of its 14 // contributors may be used to endorse or promote products derived from 15 // this software without specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 // A minimalistic implementation of getcontext() to be used by 30 // Google Breakpad when getcontext() is not available in libc. 31 32 #include "common/linux/ucontext_constants.h" 33 34 /* int getcontext (ucontext_t* ucp) */ 35 36 #if defined(__arm__) 37 38 .text 39 .global breakpad_getcontext 40 .hidden breakpad_getcontext 41 .type breakpad_getcontext, #function 42 .align 0 43 .fnstart 44 breakpad_getcontext: 45 46 /* First, save r4-r11 */ 47 add r1, r0, #(MCONTEXT_GREGS_OFFSET + 4*4) 48 stm r1, {r4-r11} 49 50 /* r12 is a scratch register, don't save it */ 51 52 /* Save sp and lr explicitly. */ 53 /* - sp can't be stored with stmia in Thumb-2 */ 54 /* - STM instructions that store sp and pc are deprecated in ARM */ 55 str sp, [r0, #(MCONTEXT_GREGS_OFFSET + 13*4)] 56 str lr, [r0, #(MCONTEXT_GREGS_OFFSET + 14*4)] 57 58 /* Save the caller's address in 'pc' */ 59 str lr, [r0, #(MCONTEXT_GREGS_OFFSET + 15*4)] 60 61 /* Save ucontext_t* pointer across next call */ 62 mov r4, r0 63 64 /* Call sigprocmask(SIG_BLOCK, NULL, &(ucontext->uc_sigmask)) */ 65 mov r0, #0 /* SIG_BLOCK */ 66 mov r1, #0 /* NULL */ 67 add r2, r4, #UCONTEXT_SIGMASK_OFFSET 68 bl sigprocmask(PLT) 69 70 /* Intentionally do not save the FPU state here. This is because on 71 * Linux/ARM, one should instead use ptrace(PTRACE_GETFPREGS) or 72 * ptrace(PTRACE_GETVFPREGS) to get it. 73 * 74 * Note that a real implementation of getcontext() would need to save 75 * this here to allow setcontext()/swapcontext() to work correctly. 76 */ 77 78 /* Restore the values of r4 and lr */ 79 mov r0, r4 80 ldr lr, [r0, #(MCONTEXT_GREGS_OFFSET + 14*4)] 81 ldr r4, [r0, #(MCONTEXT_GREGS_OFFSET + 4*4)] 82 83 /* Return 0 */ 84 mov r0, #0 85 bx lr 86 87 .fnend 88 .size breakpad_getcontext, . - breakpad_getcontext 89 90 #elif defined(__aarch64__) 91 92 #if defined(__ARM_FEATURE_PAC_DEFAULT) && __ARM_FEATURE_PAC_DEFAULT 93 // ENABLE_PAUTH must be defined to 1 since this value will be used in 94 // bitwise-shift later! 95 #define ENABLE_PAUTH 1 96 97 #if ((__ARM_FEATURE_PAC_DEFAULT&((1<<0)|(1<<1)))==0) 98 #error Pointer authentication defines no valid key! 99 #endif 100 #else 101 #define ENABLE_PAUTH 0 102 #endif 103 104 #if defined(__ARM_FEATURE_BTI_DEFAULT) && (__ARM_FEATURE_BTI_DEFAULT==1) 105 // ENABLE_BTI must be defined to 1 since this value will be used in 106 // bitwise-shift later! 107 #define ENABLE_BTI 1 108 #else 109 #define ENABLE_BTI 0 110 #endif 111 112 113 // Although Pointer Authentication and Branch Target Instructions are technically 114 // seperate features they work together, i.e. the paciasp and pacibsp instructions 115 // serve as BTI landing pads. 116 // Therefore PA-instructions are enabled when PA _or_ BTI is enabled! 117 #if ENABLE_PAUTH || ENABLE_BTI 118 // See section "Pointer Authentication" of 119 // https://developer.arm.com/documentation/101028/0012/5--Feature-test-macros 120 // for details how to interpret __ARM_FEATURE_PAC_DEFAULT 121 #if (__ARM_FEATURE_PAC_DEFAULT & (1<<0)) 122 #define PAUTH_SIGN_SP paciasp 123 #define PAUTH_AUTH_SP autiasp 124 #else 125 #define PAUTH_SIGN_SP pacibsp 126 #define PAUTH_AUTH_SP autibsp 127 #endif 128 #else 129 #define PAUTH_SIGN_SP 130 #define PAUTH_AUTH_SP 131 #endif 132 133 #define _NSIG 64 134 #define __NR_rt_sigprocmask 135 135 136 .text 137 .global breakpad_getcontext 138 .hidden breakpad_getcontext 139 .type breakpad_getcontext, #function 140 .align 4 141 .cfi_startproc 142 breakpad_getcontext: 143 144 PAUTH_SIGN_SP 145 146 /* The saved context will return to the getcontext() call point 147 with a return value of 0 */ 148 str xzr, [x0, MCONTEXT_GREGS_OFFSET + 0 * REGISTER_SIZE] 149 150 stp x18, x19, [x0, MCONTEXT_GREGS_OFFSET + 18 * REGISTER_SIZE] 151 stp x20, x21, [x0, MCONTEXT_GREGS_OFFSET + 20 * REGISTER_SIZE] 152 stp x22, x23, [x0, MCONTEXT_GREGS_OFFSET + 22 * REGISTER_SIZE] 153 stp x24, x25, [x0, MCONTEXT_GREGS_OFFSET + 24 * REGISTER_SIZE] 154 stp x26, x27, [x0, MCONTEXT_GREGS_OFFSET + 26 * REGISTER_SIZE] 155 stp x28, x29, [x0, MCONTEXT_GREGS_OFFSET + 28 * REGISTER_SIZE] 156 str x30, [x0, MCONTEXT_GREGS_OFFSET + 30 * REGISTER_SIZE] 157 158 /* Place LR into the saved PC, this will ensure that when 159 switching to this saved context with setcontext() control 160 will pass back to the caller of getcontext(), we have 161 already arranged to return the appropriate return value in x0 162 above. */ 163 str x30, [x0, MCONTEXT_PC_OFFSET] 164 165 /* Save the current SP */ 166 mov x2, sp 167 str x2, [x0, MCONTEXT_SP_OFFSET] 168 169 /* Initialize the pstate. */ 170 str xzr, [x0, MCONTEXT_PSTATE_OFFSET] 171 172 /* Figure out where to place the first context extension 173 block. */ 174 add x2, x0, #MCONTEXT_EXTENSION_OFFSET 175 176 /* Write the context extension fpsimd header. */ 177 mov w3, #(FPSIMD_MAGIC & 0xffff) 178 movk w3, #(FPSIMD_MAGIC >> 16), lsl #16 179 str w3, [x2, #FPSIMD_CONTEXT_MAGIC_OFFSET] 180 mov w3, #FPSIMD_CONTEXT_SIZE 181 str w3, [x2, #FPSIMD_CONTEXT_SIZE_OFFSET] 182 183 /* Fill in the FP SIMD context. */ 184 add x3, x2, #(FPSIMD_CONTEXT_VREGS_OFFSET + 8 * SIMD_REGISTER_SIZE) 185 stp d8, d9, [x3], #(2 * SIMD_REGISTER_SIZE) 186 stp d10, d11, [x3], #(2 * SIMD_REGISTER_SIZE) 187 stp d12, d13, [x3], #(2 * SIMD_REGISTER_SIZE) 188 stp d14, d15, [x3], #(2 * SIMD_REGISTER_SIZE) 189 190 add x3, x2, FPSIMD_CONTEXT_FPSR_OFFSET 191 192 mrs x4, fpsr 193 str w4, [x3] 194 195 mrs x4, fpcr 196 str w4, [x3, FPSIMD_CONTEXT_FPCR_OFFSET - FPSIMD_CONTEXT_FPSR_OFFSET] 197 198 /* Write the termination context extension header. */ 199 add x2, x2, #FPSIMD_CONTEXT_SIZE 200 201 str xzr, [x2, #FPSIMD_CONTEXT_MAGIC_OFFSET] 202 str xzr, [x2, #FPSIMD_CONTEXT_SIZE_OFFSET] 203 204 /* Grab the signal mask */ 205 /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ 206 add x2, x0, #UCONTEXT_SIGMASK_OFFSET 207 mov x0, #0 /* SIG_BLOCK */ 208 mov x1, #0 /* NULL */ 209 mov x3, #(_NSIG / 8) 210 mov x8, #__NR_rt_sigprocmask 211 svc 0 212 213 /* Return x0 for success */ 214 mov x0, 0 215 216 PAUTH_AUTH_SP 217 218 ret 219 220 .cfi_endproc 221 .size breakpad_getcontext, . - breakpad_getcontext 222 223 #elif defined(__i386__) 224 225 .text 226 .global breakpad_getcontext 227 .hidden breakpad_getcontext 228 .align 4 229 .type breakpad_getcontext, @function 230 231 breakpad_getcontext: 232 233 movl 4(%esp), %eax /* eax = uc */ 234 235 /* Save register values */ 236 movl %ecx, MCONTEXT_ECX_OFFSET(%eax) 237 movl %edx, MCONTEXT_EDX_OFFSET(%eax) 238 movl %ebx, MCONTEXT_EBX_OFFSET(%eax) 239 movl %edi, MCONTEXT_EDI_OFFSET(%eax) 240 movl %esi, MCONTEXT_ESI_OFFSET(%eax) 241 movl %ebp, MCONTEXT_EBP_OFFSET(%eax) 242 243 movl (%esp), %edx /* return address */ 244 lea 4(%esp), %ecx /* exclude return address from stack */ 245 mov %edx, MCONTEXT_EIP_OFFSET(%eax) 246 mov %ecx, MCONTEXT_ESP_OFFSET(%eax) 247 248 xorl %ecx, %ecx 249 movw %fs, %cx 250 mov %ecx, MCONTEXT_FS_OFFSET(%eax) 251 252 movl $0, MCONTEXT_EAX_OFFSET(%eax) 253 254 /* Save floating point state to fpregstate, then update 255 * the fpregs pointer to point to it */ 256 leal UCONTEXT_FPREGS_MEM_OFFSET(%eax), %ecx 257 fnstenv (%ecx) 258 fldenv (%ecx) 259 mov %ecx, UCONTEXT_FPREGS_OFFSET(%eax) 260 261 /* Save signal mask: sigprocmask(SIGBLOCK, NULL, &uc->uc_sigmask) */ 262 leal UCONTEXT_SIGMASK_OFFSET(%eax), %edx 263 xorl %ecx, %ecx 264 push %edx /* &uc->uc_sigmask */ 265 push %ecx /* NULL */ 266 push %ecx /* SIGBLOCK == 0 on i386 */ 267 call sigprocmask@PLT 268 addl $12, %esp 269 270 movl $0, %eax 271 ret 272 273 .size breakpad_getcontext, . - breakpad_getcontext 274 275 #elif defined(__mips__) 276 277 // This implementation is inspired by implementation of getcontext in glibc. 278 #include <asm-mips/asm.h> 279 #include <asm-mips/regdef.h> 280 #if _MIPS_SIM == _ABIO32 281 #include <asm-mips/fpregdef.h> 282 #endif 283 284 // from asm-mips/asm.h 285 #if _MIPS_SIM == _ABIO32 286 #define ALSZ 7 287 #define ALMASK ~7 288 #define SZREG 4 289 #else // _MIPS_SIM != _ABIO32 290 #define ALSZ 15 291 #define ALMASK ~15 292 #define SZREG 8 293 #endif 294 295 #include <asm/unistd.h> // for __NR_rt_sigprocmask 296 297 #define _NSIG8 128 / 8 298 #define SIG_BLOCK 1 299 300 301 .text 302 LOCALS_NUM = 1 // save gp on stack 303 FRAME_SIZE = ((LOCALS_NUM * SZREG) + ALSZ) & ALMASK 304 305 GP_FRAME_OFFSET = FRAME_SIZE - (1 * SZREG) 306 MCONTEXT_REG_SIZE = 8 307 308 #if _MIPS_SIM == _ABIO32 309 310 NESTED (breakpad_getcontext, FRAME_SIZE, ra) 311 .mask 0x00000000, 0 312 .fmask 0x00000000, 0 313 314 .set noreorder 315 .cpload t9 316 .set reorder 317 318 move a2, sp 319 #define _SP a2 320 321 addiu sp, -FRAME_SIZE 322 .cprestore GP_FRAME_OFFSET 323 324 sw s0, (16 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 325 sw s1, (17 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 326 sw s2, (18 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 327 sw s3, (19 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 328 sw s4, (20 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 329 sw s5, (21 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 330 sw s6, (22 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 331 sw s7, (23 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 332 sw _SP, (29 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 333 sw fp, (30 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 334 sw ra, (31 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 335 sw ra, MCONTEXT_PC_OFFSET(a0) 336 337 #ifdef __mips_hard_float 338 s.d fs0, (20 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 339 s.d fs1, (22 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 340 s.d fs2, (24 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 341 s.d fs3, (26 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 342 s.d fs4, (28 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 343 s.d fs5, (30 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 344 345 cfc1 v1, fcr31 346 sw v1, MCONTEXT_FPC_CSR(a0) 347 #endif // __mips_hard_float 348 349 /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ 350 li a3, _NSIG8 351 addu a2, a0, UCONTEXT_SIGMASK_OFFSET 352 move a1, zero 353 li a0, SIG_BLOCK 354 li v0, __NR_rt_sigprocmask 355 syscall 356 357 addiu sp, FRAME_SIZE 358 jr ra 359 360 END (breakpad_getcontext) 361 #else 362 363 #ifndef NESTED 364 /* 365 * NESTED - declare nested routine entry point 366 */ 367 #define NESTED(symbol, framesize, rpc) \ 368 .globl symbol; \ 369 .align 2; \ 370 .type symbol,@function; \ 371 .ent symbol,0; \ 372 symbol: .frame sp, framesize, rpc; 373 #endif 374 375 /* 376 * END - mark end of function 377 */ 378 #ifndef END 379 # define END(function) \ 380 .end function; \ 381 .size function,.-function 382 #endif 383 384 /* int getcontext (ucontext_t* ucp) */ 385 386 NESTED (breakpad_getcontext, FRAME_SIZE, ra) 387 .mask 0x10000000, 0 388 .fmask 0x00000000, 0 389 390 move a2, sp 391 #define _SP a2 392 move a3, gp 393 #define _GP a3 394 395 daddiu sp, -FRAME_SIZE 396 .cpsetup $25, GP_FRAME_OFFSET, breakpad_getcontext 397 398 /* Store a magic flag. */ 399 li v1, 1 400 sd v1, (0 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) /* zero */ 401 402 sd s0, (16 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 403 sd s1, (17 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 404 sd s2, (18 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 405 sd s3, (19 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 406 sd s4, (20 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 407 sd s5, (21 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 408 sd s6, (22 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 409 sd s7, (23 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 410 sd _GP, (28 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 411 sd _SP, (29 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 412 sd s8, (30 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 413 sd ra, (31 * MCONTEXT_REG_SIZE + MCONTEXT_GREGS_OFFSET)(a0) 414 sd ra, MCONTEXT_PC_OFFSET(a0) 415 416 #ifdef __mips_hard_float 417 s.d $f24, (24 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 418 s.d $f25, (25 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 419 s.d $f26, (26 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 420 s.d $f27, (27 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 421 s.d $f28, (28 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 422 s.d $f29, (29 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 423 s.d $f30, (30 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 424 s.d $f31, (31 * MCONTEXT_REG_SIZE + MCONTEXT_FPREGS_OFFSET)(a0) 425 426 cfc1 v1, $31 427 sw v1, MCONTEXT_FPC_CSR(a0) 428 #endif /* __mips_hard_float */ 429 430 /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ 431 li a3, _NSIG8 432 daddu a2, a0, UCONTEXT_SIGMASK_OFFSET 433 move a1, zero 434 li a0, SIG_BLOCK 435 436 li v0, __NR_rt_sigprocmask 437 syscall 438 439 .cpreturn 440 daddiu sp, FRAME_SIZE 441 move v0, zero 442 jr ra 443 444 END (breakpad_getcontext) 445 #endif // _MIPS_SIM == _ABIO32 446 447 #elif defined(__x86_64__) 448 /* The x64 implementation of breakpad_getcontext was derived in part 449 from the implementation of libunwind which requires the following 450 notice. */ 451 /* libunwind - a platform-independent unwind library 452 Copyright (C) 2008 Google, Inc 453 Contributed by Paul Pluzhnikov <ppluzhnikov@google.com> 454 Copyright (C) 2010 Konstantin Belousov <kib@freebsd.org> 455 456 This file is part of libunwind. 457 458 Permission is hereby granted, free of charge, to any person obtaining 459 a copy of this software and associated documentation files (the 460 "Software"), to deal in the Software without restriction, including 461 without limitation the rights to use, copy, modify, merge, publish, 462 distribute, sublicense, and/or sell copies of the Software, and to 463 permit persons to whom the Software is furnished to do so, subject to 464 the following conditions: 465 466 The above copyright notice and this permission notice shall be 467 included in all copies or substantial portions of the Software. 468 469 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 470 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 471 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 472 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 473 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 474 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 475 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ 476 477 .text 478 .global breakpad_getcontext 479 .hidden breakpad_getcontext 480 .align 4 481 .type breakpad_getcontext, @function 482 483 breakpad_getcontext: 484 .cfi_startproc 485 486 /* Callee saved: RBX, RBP, R12-R15 */ 487 movq %r12, MCONTEXT_GREGS_R12(%rdi) 488 movq %r13, MCONTEXT_GREGS_R13(%rdi) 489 movq %r14, MCONTEXT_GREGS_R14(%rdi) 490 movq %r15, MCONTEXT_GREGS_R15(%rdi) 491 movq %rbp, MCONTEXT_GREGS_RBP(%rdi) 492 movq %rbx, MCONTEXT_GREGS_RBX(%rdi) 493 494 /* Save argument registers (not strictly needed, but setcontext 495 restores them, so don't restore garbage). */ 496 movq %r8, MCONTEXT_GREGS_R8(%rdi) 497 movq %r9, MCONTEXT_GREGS_R9(%rdi) 498 movq %rdi, MCONTEXT_GREGS_RDI(%rdi) 499 movq %rsi, MCONTEXT_GREGS_RSI(%rdi) 500 movq %rdx, MCONTEXT_GREGS_RDX(%rdi) 501 movq %rax, MCONTEXT_GREGS_RAX(%rdi) 502 movq %rcx, MCONTEXT_GREGS_RCX(%rdi) 503 504 /* Save fp state (not needed, except for setcontext not 505 restoring garbage). */ 506 leaq MCONTEXT_FPREGS_MEM(%rdi),%r8 507 movq %r8, MCONTEXT_FPREGS_PTR(%rdi) 508 fnstenv (%r8) 509 stmxcsr FPREGS_OFFSET_MXCSR(%r8) 510 511 leaq 8(%rsp), %rax /* exclude this call. */ 512 movq %rax, MCONTEXT_GREGS_RSP(%rdi) 513 514 movq 0(%rsp), %rax 515 movq %rax, MCONTEXT_GREGS_RIP(%rdi) 516 517 /* Save signal mask: sigprocmask(SIGBLOCK, NULL, &uc->uc_sigmask) */ 518 leaq UCONTEXT_SIGMASK_OFFSET(%rdi), %rdx // arg3 519 xorq %rsi, %rsi // arg2 NULL 520 xorq %rdi, %rdi // arg1 SIGBLOCK == 0 521 call sigprocmask@PLT 522 523 /* Always return 0 for success, even if sigprocmask failed. */ 524 xorl %eax, %eax 525 ret 526 .cfi_endproc 527 .size breakpad_getcontext, . - breakpad_getcontext 528 529 #elif defined(__riscv) 530 531 # define SIG_BLOCK 0 532 # define _NSIG8 8 533 # define __NR_rt_sigprocmask 135 534 535 .text 536 .globl breakpad_getcontext 537 .type breakpad_getcontext, @function 538 .align 0 539 .cfi_startproc 540 breakpad_getcontext: 541 REG_S ra, MCONTEXT_GREGS_PC(a0) 542 REG_S ra, MCONTEXT_GREGS_RA(a0) 543 REG_S sp, MCONTEXT_GREGS_SP(a0) 544 REG_S gp, MCONTEXT_GREGS_SP(a0) 545 REG_S tp, MCONTEXT_GREGS_TP(a0) 546 REG_S t0, MCONTEXT_GREGS_T0(a0) 547 REG_S t1, MCONTEXT_GREGS_T1(a0) 548 REG_S t2, MCONTEXT_GREGS_T2(a0) 549 REG_S s0, MCONTEXT_GREGS_S0(a0) 550 REG_S s1, MCONTEXT_GREGS_S1(a0) 551 REG_S a0, MCONTEXT_GREGS_A0(a0) 552 REG_S a1, MCONTEXT_GREGS_A1(a0) 553 REG_S a2, MCONTEXT_GREGS_A2(a0) 554 REG_S a3, MCONTEXT_GREGS_A3(a0) 555 REG_S a4, MCONTEXT_GREGS_A4(a0) 556 REG_S a5, MCONTEXT_GREGS_A5(a0) 557 REG_S a6, MCONTEXT_GREGS_A6(a0) 558 REG_S a7, MCONTEXT_GREGS_A7(a0) 559 REG_S s2, MCONTEXT_GREGS_S2(a0) 560 REG_S s3, MCONTEXT_GREGS_S3(a0) 561 REG_S s4, MCONTEXT_GREGS_S4(a0) 562 REG_S s5, MCONTEXT_GREGS_S5(a0) 563 REG_S s6, MCONTEXT_GREGS_S6(a0) 564 REG_S s7, MCONTEXT_GREGS_S7(a0) 565 REG_S s8, MCONTEXT_GREGS_S8(a0) 566 REG_S s9, MCONTEXT_GREGS_S9(a0) 567 REG_S s10, MCONTEXT_GREGS_S10(a0) 568 REG_S s11, MCONTEXT_GREGS_S11(a0) 569 REG_S t3, MCONTEXT_GREGS_T3(a0) 570 REG_S t4, MCONTEXT_GREGS_T4(a0) 571 REG_S t5, MCONTEXT_GREGS_T5(a0) 572 REG_S t6 , MCONTEXT_GREGS_T6(a0) 573 # ifndef __riscv_float_abi_soft 574 frsr a1 575 576 FREG_S ft0, MCONTEXT_FPREGS_FT0(a0) 577 FREG_S ft1, MCONTEXT_FPREGS_FT1(a0) 578 FREG_S ft2, MCONTEXT_FPREGS_FT2(a0) 579 FREG_S ft3, MCONTEXT_FPREGS_FT3(a0) 580 FREG_S ft4, MCONTEXT_FPREGS_FT4(a0) 581 FREG_S ft5, MCONTEXT_FPREGS_FT5(a0) 582 FREG_S ft6, MCONTEXT_FPREGS_FT6(a0) 583 FREG_S ft7, MCONTEXT_FPREGS_FT7(a0) 584 FREG_S fs0, MCONTEXT_FPREGS_FS0(a0) 585 FREG_S fs1, MCONTEXT_FPREGS_FS1(a0) 586 FREG_S fa0, MCONTEXT_FPREGS_FA0(a0) 587 FREG_S fa1, MCONTEXT_FPREGS_FA1(a0) 588 FREG_S fa2, MCONTEXT_FPREGS_FA2(a0) 589 FREG_S fa3, MCONTEXT_FPREGS_FA3(a0) 590 FREG_S fa4, MCONTEXT_FPREGS_FA4(a0) 591 FREG_S fa5, MCONTEXT_FPREGS_FA5(a0) 592 FREG_S fa6, MCONTEXT_FPREGS_FA6(a0) 593 FREG_S fa7, MCONTEXT_FPREGS_FA7(a0) 594 FREG_S fs2, MCONTEXT_FPREGS_FS2(a0) 595 FREG_S fs3, MCONTEXT_FPREGS_FS3(a0) 596 FREG_S fs4, MCONTEXT_FPREGS_FS4(a0) 597 FREG_S fs5, MCONTEXT_FPREGS_FS5(a0) 598 FREG_S fs6, MCONTEXT_FPREGS_FS6(a0) 599 FREG_S fs7, MCONTEXT_FPREGS_FS7(a0) 600 FREG_S fs8, MCONTEXT_FPREGS_FS8(a0) 601 FREG_S fs9, MCONTEXT_FPREGS_FS9(a0) 602 FREG_S fs10, MCONTEXT_FPREGS_FS10(a0) 603 FREG_S fs11, MCONTEXT_FPREGS_FS11(a0) 604 FREG_S ft8, MCONTEXT_FPREGS_FT8(a0) 605 FREG_S ft9, MCONTEXT_FPREGS_FT9(a0) 606 FREG_S ft10, MCONTEXT_FPREGS_FT10(a0) 607 FREG_S ft11, MCONTEXT_FPREGS_FT11(a0) 608 609 sw a1, MCONTEXT_FPC_CSR(a0) 610 # endif // __riscv_float_abi_soft 611 mv a1, zero 612 add a2, a0, UCONTEXT_SIGMASK_OFFSET 613 li a3, _NSIG8 614 mv a0, zero 615 li a7, __NR_rt_sigprocmask 616 ecall 617 mv a0, zero 618 ret 619 620 .cfi_endproc 621 .size breakpad_getcontext, . - breakpad_getcontext 622 623 #else 624 # error "This file has not been ported for your CPU!" 625 #endif 626 627 #if defined(__aarch64__) 628 // ENABLE_PAUTH and ENABLE_BTI would be enabled at the definition 629 // of AArch64 specific breakpad_getcontext function 630 #if ENABLE_PAUTH || ENABLE_BTI 631 // for further information on the .note.gnu.property section see 632 // https://github.com/ARM-software/abi-aa/blob/main/aaelf64/aaelf64.rst#program-property 633 .pushsection .note.gnu.property, "a"; 634 .balign 8 635 .long 4 636 .long 0x10 637 .long 0x5 638 .asciz "GNU" 639 .long 0xc0000000 /* GNU_PROPERTY_AARCH64_FEATURE_1_AND */ 640 .long 4 641 .long ((ENABLE_PAUTH)<<1) | ((ENABLE_BTI)<<0) /* PAuth and BTI */ 642 .long 0 643 .popsection 644 #endif 645 #endif