sysdeps/unix/sysv/linux/sparc/sparc32/swapcontext.S

   1 /* Save current context and install the given one.
   2    Copyright (C) 2008-2020 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by David S. Miller <davem@davemloft.net>, 2008.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <sysdep.h>
  21 #include <sys/trap.h>
  22
  23 #include "ucontext_i.h"
  24
  25
  26 /* int __swapcontext (ucontext_t *oucp, const ucontext_t *ucp);
  27
  28   Saves the machine context in oucp such that when it is activated,
  29   it appears as if __swapcontext() returned again, restores the
  30   machine context in ucp and thereby resumes execution in that
  31   context.
  32
  33   This implementation is intended to be used for *synchronous* context
  34   switches only.  Therefore, it does not have to save anything
  35   other than the PRESERVED state.  */
  36
  37 ENTRY(__swapcontext)
  38         save    %sp, -112, %sp
  39         ta      ST_FLUSH_WINDOWS
  40         st      %g0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_PSR]
  41         add     %i7, 8, %o0
  42         st      %o0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_PC]
  43         add     %o0, 4, %o0
  44         st      %o0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_NPC]
  45         rd      %y, %o1
  46         st      %o1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_Y]
  47         st      %g1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G1]
  48         st      %g2, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G2]
  49         st      %g3, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G3]
  50         st      %g4, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G4]
  51         st      %g5, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G5]
  52         st      %g6, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G6]
  53         st      %g7, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G7]
  54         st      %g0, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O0]
  55         st      %i1, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O1]
  56         st      %i2, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O2]
  57         st      %i3, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O3]
  58         st      %i4, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O4]
  59         st      %i5, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O5]
  60         st      %i6, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O6]
  61         st      %i7, [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O7]
  62         st      %g0, [%i0 + UC_MCONTEXT + MC_GWINS]
  63         stb     %g0, [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_EN]
  64         st      %g0, [%i0 + UC_MCONTEXT + MC_XRS + XRS_ID]
  65         st      %g0, [%i0 + UC_MCONTEXT + MC_XRS + XRS_PTR]
  66
  67         mov     SIG_SETMASK, %o0
  68         add     %i1, UC_SIGMASK, %o1
  69         add     %i0, UC_SIGMASK, %o2
  70         mov     8, %o3
  71         mov     __NR_rt_sigprocmask, %g1
  72         ta      0x10
  73
  74         mov     %i1, %i0
  75         ldub    [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_EN], %g1
  76         cmp     %g1, 0
  77         be      1f
  78          nop
  79         ld      [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_FSR], %fsr
  80         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D0], %f0
  81         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D2], %f2
  82         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D4], %f4
  83         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D6], %f6
  84         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D8], %f8
  85         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D10], %f10
  86         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D12], %f12
  87         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D14], %f14
  88         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D16], %f16
  89         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D18], %f18
  90         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D20], %f20
  91         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D22], %f22
  92         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D24], %f24
  93         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D26], %f26
  94         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D28], %f28
  95         ldd     [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D30], %f30
  96 1:
  97         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_Y], %g1
  98         wr      %g1, 0x0, %y
  99         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G2], %g2
 100         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G3], %g3
 101         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G4], %g4
 102         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G5], %g5
 103         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G6], %g6
 104         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G7], %g7
 105         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O1], %i1
 106         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O2], %i2
 107         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O3], %i3
 108         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O4], %i4
 109         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O5], %i5
 110         ld      [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O6], %i6
 111         restore
 112         ld      [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O7], %o7
 113         ld      [%o0 + UC_MCONTEXT + MC_GREGS + GREG_PC], %g1
 114         jmpl    %g1, %g0
 115          ld     [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O0], %o0
 116 END(__swapcontext)
 117
 118 weak_alias (__swapcontext, swapcontext)