1/* Swap two contexts. OpenRISC version. 2 Copyright (C) 2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19#include <sysdep.h> 20#include "ucontext_i.h" 21 22/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */ 23 .text 24ENTRY(__swapcontext) 25 26 /* Same as getcontext. */ 27 /* Store r1, the stack pointer. */ 28 l.sw (UCONTEXT_MCONTEXT + 1*4)(r3), r1 29 /* Store r2, the frame pointer. */ 30 l.sw (UCONTEXT_MCONTEXT + 2*4)(r3), r2 31 /* Store r9, the link register. */ 32 l.sw (UCONTEXT_MCONTEXT + 9*4)(r3), r9 33 /* Store r9 to reg[11] too, as we need two links for makecontext. */ 34 l.sw (UCONTEXT_MCONTEXT + 11*4)(r3), r9 35 /* Store r10, the TLS register. */ 36 l.sw (UCONTEXT_MCONTEXT + 10*4)(r3), r10 37 /* Store r14-r30 even, callee saved registers. */ 38 l.sw (UCONTEXT_MCONTEXT + 14*4)(r3), r14 39 l.sw (UCONTEXT_MCONTEXT + 16*4)(r3), r16 40 l.sw (UCONTEXT_MCONTEXT + 18*4)(r3), r18 41 l.sw (UCONTEXT_MCONTEXT + 20*4)(r3), r20 42 l.sw (UCONTEXT_MCONTEXT + 22*4)(r3), r22 43 l.sw (UCONTEXT_MCONTEXT + 24*4)(r3), r24 44 l.sw (UCONTEXT_MCONTEXT + 26*4)(r3), r26 45 l.sw (UCONTEXT_MCONTEXT + 28*4)(r3), r28 46 l.sw (UCONTEXT_MCONTEXT + 30*4)(r3), r30 47 48 /* Store ucp to non-argument syscall preserved register. */ 49 l.ori r30, r4, 0 50 51 /* Get signal mask. */ 52 /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ 53 l.ori r6, r0, _NSIG8 54 l.addi r5, r3, UCONTEXT_SIGMASK 55 l.ori r4, r0, 0 56 l.ori r3, r0, SIG_BLOCK 57 l.ori r11, r0, SYS_ify (rt_sigprocmask) 58 /* Do the syscall. */ 59 l.sys 1 60 l.nop 61 62 /* if -4096 < ret < 0 holds, it's an error */ 63 l.sfgeui r11, 0xf001 64 l.bf 1f 65 l.nop 66 67 /* Same as setcontext. */ 68 69 /* Restore signal mask. */ 70 /* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */ 71 l.ori r6, r0, _NSIG8 72 l.ori r5, r0, 0 73 l.addi r4, r30, UCONTEXT_SIGMASK 74 l.ori r3, r0, SIG_SETMASK 75 l.ori r11, r0, SYS_ify (rt_sigprocmask) 76 /* Do the syscall. */ 77 l.sys 1 78 l.nop 79 80 /* if -4096 < ret < 0 holds, it's an error */ 81 l.sfgeui r11, 0xf001 82 l.bf 1f 83 l.nop 84 85 /* Restore argument registers, for the makecontext case. */ 86 l.lwz r3, (UCONTEXT_MCONTEXT + 3*4)(r30) 87 l.lwz r4, (UCONTEXT_MCONTEXT + 4*4)(r30) 88 l.lwz r5, (UCONTEXT_MCONTEXT + 5*4)(r30) 89 l.lwz r6, (UCONTEXT_MCONTEXT + 6*4)(r30) 90 l.lwz r7, (UCONTEXT_MCONTEXT + 7*4)(r30) 91 l.lwz r8, (UCONTEXT_MCONTEXT + 8*4)(r30) 92 93 /* Restore registers stored in getcontext. */ 94 l.lwz r1, (UCONTEXT_MCONTEXT + 1*4)(r30) 95 l.lwz r2, (UCONTEXT_MCONTEXT + 2*4)(r30) 96 l.lwz r9, (UCONTEXT_MCONTEXT + 9*4)(r30) 97 l.lwz r10, (UCONTEXT_MCONTEXT + 10*4)(r30) 98 l.lwz r11, (UCONTEXT_MCONTEXT + 11*4)(r30) 99 l.lwz r14, (UCONTEXT_MCONTEXT + 14*4)(r30) 100 l.lwz r16, (UCONTEXT_MCONTEXT + 16*4)(r30) 101 l.lwz r18, (UCONTEXT_MCONTEXT + 18*4)(r30) 102 l.lwz r20, (UCONTEXT_MCONTEXT + 20*4)(r30) 103 l.lwz r22, (UCONTEXT_MCONTEXT + 22*4)(r30) 104 l.lwz r24, (UCONTEXT_MCONTEXT + 24*4)(r30) 105 l.lwz r26, (UCONTEXT_MCONTEXT + 26*4)(r30) 106 l.lwz r28, (UCONTEXT_MCONTEXT + 28*4)(r30) 107 l.lwz r30, (UCONTEXT_MCONTEXT + 30*4)(r30) 108 109 l.jr r11 110 l.ori r11, r0, 0 111 1121: l.j __syscall_error 113 l.ori r3, r11, 0 114 115END (__swapcontext) 116weak_alias (__swapcontext, swapcontext) 117