| 1 | /* Copyright (C) 2001-2024 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | |
| 4 | The GNU C Library is free software; you can redistribute it and/or |
| 5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either |
| 7 | version 2.1 of the License, or (at your option) any later version. |
| 8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | Lesser General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU Lesser General Public |
| 15 | License along with the GNU C Library; if not, see |
| 16 | <https://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <sysdep.h> |
| 19 | #include <features.h> |
| 20 | |
| 21 | #include "ucontext_i.h" |
| 22 | |
| 23 | #include <shlib-compat.h> |
| 24 | |
| 25 | /* __getcontext (const ucontext_t *ucp) |
| 26 | |
| 27 | Saves the machine context in UCP such that when it is activated, |
| 28 | it appears as if __getcontext() returned again. |
| 29 | |
| 30 | This implementation is intended to be used for *synchronous* context |
| 31 | switches only. Therefore, it does not have to save anything |
| 32 | other than the PRESERVED state. */ |
| 33 | |
| 34 | ENTRY(__getcontext) |
| 35 | lr %r0,%r2 |
| 36 | |
| 37 | /* rt_sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask, sigsetsize). */ |
| 38 | la %r4,SC_MASK(%r2) |
| 39 | la %r2,SIG_BLOCK |
| 40 | slr %r3,%r3 |
| 41 | lhi %r5,_NSIG8 |
| 42 | lhi %r1,SYS_ify(rt_sigprocmask) |
| 43 | svc 0 |
| 44 | |
| 45 | /* Store fpu context. */ |
| 46 | lr %r1,%r0 |
| 47 | stfpc SC_FPC(%r1) |
| 48 | std %f0,SC_FPRS(%r1) |
| 49 | std %f1,SC_FPRS+8(%r1) |
| 50 | std %f2,SC_FPRS+16(%r1) |
| 51 | std %f3,SC_FPRS+24(%r1) |
| 52 | std %f4,SC_FPRS+32(%r1) |
| 53 | std %f5,SC_FPRS+40(%r1) |
| 54 | std %f6,SC_FPRS+48(%r1) |
| 55 | std %f7,SC_FPRS+56(%r1) |
| 56 | std %f8,SC_FPRS+64(%r1) |
| 57 | std %f9,SC_FPRS+72(%r1) |
| 58 | std %f10,SC_FPRS+80(%r1) |
| 59 | std %f11,SC_FPRS+88(%r1) |
| 60 | std %f12,SC_FPRS+96(%r1) |
| 61 | std %f13,SC_FPRS+104(%r1) |
| 62 | std %f14,SC_FPRS+112(%r1) |
| 63 | std %f15,SC_FPRS+120(%r1) |
| 64 | |
| 65 | /* Set __getcontext return value to 0. */ |
| 66 | slr %r2,%r2 |
| 67 | |
| 68 | /* Store access registers. */ |
| 69 | stam %a0,%a15,SC_ACRS(%r1) |
| 70 | |
| 71 | /* Store general purpose registers. */ |
| 72 | stm %r0,%r15,SC_GPRS(%r1) |
| 73 | |
| 74 | /* Store psw mask to 0x0 and addr to return address. Then the address |
| 75 | can be retrieved from the ucontext structure in the same way as if it |
| 76 | is created by kernel and passed to a signal-handler. */ |
| 77 | st %r2,SC_PSW+0(%r1) |
| 78 | st %r14,SC_PSW+4(%r1) |
| 79 | |
| 80 | /* Return. */ |
| 81 | br %r14 |
| 82 | END(__getcontext) |
| 83 | |
| 84 | #if defined SHARED && SHLIB_COMPAT (libc, GLIBC_2_19, GLIBC_2_20) |
| 85 | /* In glibc release 2.19 a new version of getcontext was introduced, |
| 86 | but was reverted before 2.20. Thus both versions are the same function. */ |
| 87 | weak_alias (__getcontext, __v1__getcontext) |
| 88 | weak_alias (__getcontext, __v2__getcontext) |
| 89 | versioned_symbol (libc, __v1__getcontext, getcontext, GLIBC_2_1) |
| 90 | compat_symbol (libc, __v2__getcontext, getcontext, GLIBC_2_19) |
| 91 | |
| 92 | #else |
| 93 | |
| 94 | weak_alias (__getcontext, getcontext) |
| 95 | |
| 96 | #endif /* !(defined SHARED && SHLIB_COMPAT (libc, GLIBC_2_19, GLIBC_2_20)) */ |
| 97 | |