1/* Save current context and install the given one. 2 Copyright (C) 2012-2021 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 21#include "ucontext_i.h" 22 23 24ENTRY(__swapcontext) 25 /* Load address of the context data structure we save in. */ 26 move.l 4(%sp), %a0 27 28 /* Save the preserved registers and the return address. */ 29 movem.l %d2-%d7, oGREGS+2*4(%a0) 30 movem.l %a2-%a6, oGREGS+10*4(%a0) 31 lea 4(%sp), %a1 32 move.l %a1, oSP(%a0) 33 move.l (%sp), oPC(%a0) 34 fmovem.l %fpsr/%fpcr/%fpiar, oFPREGS(%a0) 35 fmovem.x %fp2-%fp7, oFP2(%a0) 36 cfi_def_cfa (%a0, 0) 37 cfi_offset (%d2, oGREGS+2*4) 38 cfi_offset (%d3, oGREGS+3*4) 39 cfi_offset (%a2, oGREGS+10*4) 40 cfi_offset (%pc, oPC) 41 42 /* Load address of the context data structure we have to load. */ 43 move.l 8(%sp), %a1 44 45 /* Save the current signal mask and install the new one. */ 46 lea oSIGMASK(%a0), %a2 47 move.l %a2, %d3 48 lea oSIGMASK(%a1), %a2 49 move.l %a2, %d2 50 move.l #SIG_SETMASK, %d1 51 move.l #__NR_sigprocmask, %d0 52 trap #0 53 cmp.l #-4095, %d0 /* Check %d0 for error. */ 54 jcs 0f 55 /* Restore registers. */ 56 move.l oGREGS+2*4(%a0), %d2 57 cfi_restore (%d2) 58 move.l oGREGS+3*4(%a0), %d3 59 cfi_restore (%d3) 60 move.l oGREGS+10*4(%a0), %a2 61 cfi_restore (%a2) 62 jra SYSCALL_ERROR_LABEL /* Jump to error handler. */ 63 640: /* Load the new stack pointer. */ 65 move.l oSP(%a1), %sp 66 cfi_def_cfa (%a1, 0) 67 cfi_offset (%d2, oGREGS+2*4) 68 cfi_offset (%d3, oGREGS+3*4) 69 cfi_offset (%d4, oGREGS+4*4) 70 cfi_offset (%d5, oGREGS+5*4) 71 cfi_offset (%d6, oGREGS+6*4) 72 cfi_offset (%d7, oGREGS+7*4) 73 cfi_offset (%a2, oGREGS+10*4) 74 cfi_offset (%a3, oGREGS+11*4) 75 cfi_offset (%a4, oGREGS+12*4) 76 cfi_offset (%a5, oGREGS+13*4) 77 cfi_offset (%a6, oGREGS+14*4) 78 cfi_offset (%fp2, oFP2+0*12) 79 cfi_offset (%fp3, oFP2+1*12) 80 cfi_offset (%fp4, oFP2+2*12) 81 cfi_offset (%fp5, oFP2+3*12) 82 cfi_offset (%fp6, oFP2+4*12) 83 cfi_offset (%fp7, oFP2+5*12) 84 cfi_offset (%pc, oPC) 85 86 /* Load the values of all the preserved registers (except SP). */ 87 movem.l oGREGS+2*4(%a1), %d2-%d7 88 movem.l oGREGS+10*4(%a1), %a2-%a6 89 fmovem.l oFPREGS(%a1), %fpsr/%fpcr/%fpiar 90 fmovem.x oFP2(%a1), %fp2-%fp7 91 92 /* Clear D0 to indicate success. */ 93 clr.l %d0 94 95 /* Fetch the address to return to. */ 96 move.l oPC(%a1), %a0 97 98 /* End FDE here, we fall into another context. */ 99 cfi_endproc 100 cfi_startproc 101 cfi_register (%pc, %a0) 102 103 jmp (%a0) 104 105 cfi_offset (%pc, -4) 106PSEUDO_END(__swapcontext) 107 108weak_alias (__swapcontext, swapcontext) 109