1 /* Save current context.
3 Copyright (C) 2009-2013 Free Software Foundation, Inc.
5 This file is part of the GNU C Library.
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public License as
9 published by the Free Software Foundation; either version 2.1 of the
10 License, or (at your option) any later version.
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, see
19 <http://www.gnu.org/licenses/>. */
22 #include "ucontext_i.h"
23 #include "ucontext-internal.h"
25 /* int getcontext (ucontext_t *ucp)
27 Returns 0 on success -1 and errno on failure.
33 /* The saved context will return to the getcontext() call point
34 with a return value of 0 */
35 str xzr, [x0, oX0 + 0 * SZREG]
37 stp x18, x19, [x0, oX0 + 18 * SZREG]
38 stp x20, x21, [x0, oX0 + 20 * SZREG]
39 stp x22, x23, [x0, oX0 + 22 * SZREG]
40 stp x24, x25, [x0, oX0 + 24 * SZREG]
41 stp x26, x27, [x0, oX0 + 26 * SZREG]
42 stp x28, x29, [x0, oX0 + 28 * SZREG]
43 str x30, [x0, oX0 + 30 * SZREG]
45 /* Place LR into the saved PC, this will ensure that when
46 switching to this saved context with setcontext() control
47 will pass back to the caller of getcontext(), we have
48 already arrange to return the appropriate return value in x0
52 /* Save the current SP */
56 /* Figure out where to place the first context extension
58 add x2, x0, #oEXTENSION
60 /* Write the context extension fpsimd header. */
61 mov w3, #(FPSIMD_MAGIC & 0xffff)
62 movk w3, #(FPSIMD_MAGIC >> 16), lsl #16
63 str w3, [x2, #oHEAD + oMAGIC]
64 mov w3, #FPSIMD_CONTEXT_SIZE
65 str w3, [x2, #oHEAD + oSIZE]
67 /* Fill in the FP SIMD context. */
68 add x3, x2, #oV0 + 8 * SZVREG
69 stp d8, d9, [x3], # 2 * SZVREG
70 stp d10, d11, [x3], # 2 * SZVREG
71 stp d12, d13, [x3], # 2 * SZVREG
72 stp d14, d15, [x3], # 2 * SZVREG
80 str w4, [x3, oFPCR - oFPSR]
82 /* Write the termination context extension header. */
83 add x2, x2, #FPSIMD_CONTEXT_SIZE
85 str xzr, [x2, #oHEAD + oMAGIC]
86 str xzr, [x2, #oHEAD + oSIZE]
88 /* Grab the signal mask */
89 /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
90 add x2, x0, #UCONTEXT_SIGMASK
94 mov x8, SYS_ify (rt_sigprocmask)
98 /* Return 0 for success */
102 b C_SYMBOL_NAME(__syscall_error)
104 PSEUDO_END (__getcontext)
105 weak_alias (__getcontext, getcontext)