sysdeps/s390/s390-32/__longjmp.c

   1 /* Copyright (C) 2000-2022 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 <errno.h>
  19 #include <sysdep.h>
  20 #include <setjmp.h>
  21 #include <bits/setjmp.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <stap-probe.h>
  25
  26 /* Jump to the position specified by ENV, causing the
  27    setjmp call there to return VAL, or 1 if VAL is 0.  */
  28 void
  29 __longjmp (__jmp_buf env, int val)
  30 {
  31 #ifdef PTR_DEMANGLE
  32   uintptr_t guard = THREAD_GET_POINTER_GUARD ();
  33 # ifdef CHECK_SP
  34   CHECK_SP (env, guard);
  35 # endif
  36 #elif defined CHECK_SP
  37   CHECK_SP (env, 0);
  38 #endif
  39   register int r2 __asm__ ("%r2") = val == 0 ? 1 : val;
  40 #ifdef PTR_DEMANGLE
  41   register uintptr_t r3 __asm__ ("%r3") = guard;
  42   register void *r1 __asm__ ("%r1") = (void *) env;
  43 #endif
  44   /* Restore registers and jump back.  */
  45   __asm__ __volatile__ (
  46                 /* longjmp probe expects longjmp first argument, second
  47                    argument and target address.  */
  48 #ifdef PTR_DEMANGLE
  49                         "lm   %%r4,%%r5,32(%1)\n\t"
  50                         "xr   %%r4,%2\n\t"
  51                         "xr   %%r5,%2\n\t"
  52                         LIBC_PROBE_ASM (longjmp, 4@%1 -4@%0 4@%%r4)
  53 #else
  54                         LIBC_PROBE_ASM (longjmp, 4@%1 -4@%0 4@%%r14)
  55 #endif
  56
  57                         /* restore fpregs  */
  58                         "ld   %%f6,48(%1)\n\t"
  59                         "ld   %%f4,40(%1)\n\t"
  60
  61                         /* restore gregs and return to jmp_buf target  */
  62 #ifdef PTR_DEMANGLE
  63                         "lm   %%r6,%%r13,0(%1)\n\t"
  64                         "lr   %%r15,%%r5\n\t"
  65                         LIBC_PROBE_ASM (longjmp_target, 4@%1 -4@%0 4@%%r4)
  66                         "br   %%r4"
  67 #else
  68                         "lm   %%r6,%%r15,0(%1)\n\t"
  69                         LIBC_PROBE_ASM (longjmp_target, 4@%1 -4@%0 4@%%r14)
  70                         "br   %%r14"
  71 #endif
  72                         : : "r" (r2),
  73 #ifdef PTR_DEMANGLE
  74                           "r" (r1), "r" (r3)
  75 #else
  76                           "a" (env)
  77 #endif
  78                         );
  79
  80   /* Avoid `volatile function does return' warnings.  */
  81   for (;;);
  82 }