1  /* Copyright (C) 2000-2023 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 <pointer_guard.h>
      21  #include <setjmp.h>
      22  #include <bits/setjmp.h>
      23  #include <stdlib.h>
      24  #include <unistd.h>
      25  #include <stap-probe.h>
      26  
      27  /* See sysdeps/unix/sysv/linux/s390/s390-32/pointer_guard.h.  */
      28  #if IS_IN (rtld)
      29  # undef PTR_DEMANGLE
      30  #endif
      31  
      32  /* Jump to the position specified by ENV, causing the
      33     setjmp call there to return VAL, or 1 if VAL is 0.  */
      34  void
      35  __longjmp (__jmp_buf env, int val)
      36  {
      37  #ifdef PTR_DEMANGLE
      38    uintptr_t guard = THREAD_GET_POINTER_GUARD ();
      39  # ifdef CHECK_SP
      40    CHECK_SP (env, guard);
      41  # endif
      42  #elif defined CHECK_SP
      43    CHECK_SP (env, 0);
      44  #endif
      45    register int r2 __asm__ ("%r2") = val == 0 ? 1 : val;
      46  #ifdef PTR_DEMANGLE
      47    register uintptr_t r3 __asm__ ("%r3") = guard;
      48    register void *r1 __asm__ ("%r1") = (void *) env;
      49  #endif
      50    /* Restore registers and jump back.  */
      51    __asm__ __volatile__ (
      52  		/* longjmp probe expects longjmp first argument, second
      53  		   argument and target address.  */
      54  #ifdef PTR_DEMANGLE
      55  			"lm   %%r4,%%r5,32(%1)\n\t"
      56  			"xr   %%r4,%2\n\t"
      57  			"xr   %%r5,%2\n\t"
      58  			LIBC_PROBE_ASM (longjmp, 4@%1 -4@%0 4@%%r4)
      59  #else
      60  			LIBC_PROBE_ASM (longjmp, 4@%1 -4@%0 4@%%r14)
      61  #endif
      62  
      63  			/* restore fpregs  */
      64  			"ld   %%f6,48(%1)\n\t"
      65  			"ld   %%f4,40(%1)\n\t"
      66  
      67  			/* restore gregs and return to jmp_buf target  */
      68  #ifdef PTR_DEMANGLE
      69  			"lm   %%r6,%%r13,0(%1)\n\t"
      70  			"lr   %%r15,%%r5\n\t"
      71  			LIBC_PROBE_ASM (longjmp_target, 4@%1 -4@%0 4@%%r4)
      72  			"br   %%r4"
      73  #else
      74  			"lm   %%r6,%%r15,0(%1)\n\t"
      75  			LIBC_PROBE_ASM (longjmp_target, 4@%1 -4@%0 4@%%r14)
      76  			"br   %%r14"
      77  #endif
      78  			: : "r" (r2),
      79  #ifdef PTR_DEMANGLE
      80  			  "r" (r1), "r" (r3)
      81  #else
      82  			  "a" (env)
      83  #endif
      84  			);
      85  
      86    /* Avoid `volatile function does return' warnings.  */
      87    for (;;);
      88  }