arch/x86_64-all/clib/longjmp.s

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id: longjmp.s 12741 2001-12-08 18:16:08Z chodorowski $
   4
   5     Desc: ANSI C function longjmp()
   6     Lang: english
   7 */
   8
   9 /******************************************************************************
  10
  11     NAME
  12 #include <setjmp.h>
  13
  14         void longjmp (jmp_buf env, int val);
  15
  16     FUNCTION
  17         Save the current context so that you can return to it later.
  18
  19     INPUTS
  20         env - The context/environment to restore
  21         val - This value is returned by setjmp() when you return to the
  22                 saved context. You cannot return 0. If val is 0, then
  23                 setjmp() returns with 1.
  24
  25     RESULT
  26         This function doesn't return.
  27
  28     NOTES
  29
  30     EXAMPLE
  31         jmp_buf env;
  32
  33         ... some code ...
  34
  35         if (!setjmp (env))
  36         {
  37             ... this code is executed after setjmp() returns ...
  38
  39             // This is no good example on how to use this function
  40             // You should not do that
  41             if (error)
  42                 longjmp (env, 5);
  43
  44             ... some code ...
  45         }
  46         else
  47         {
  48             ... this code is executed if you call longjmp(env) ...
  49         }
  50
  51     BUGS
  52
  53     SEE ALSO
  54         setjmp()
  55
  56     INTERNALS
  57
  58     HISTORY
  59
  60 ******************************************************************************/
  61
  62         #include "aros/x86_64/asm.h"
  63
  64         .text
  65         _ALIGNMENT
  66         .globl  AROS_CDEFNAME(longjmp)
  67         _FUNCTION(AROS_CDEFNAME(longjmp))
  68
  69         .set    FirstArg, 8 /* Skip Return-Adress */
  70         .set    env, FirstArg
  71         .set    val, env+8
  72         .set    retaddr, 0
  73
  74 AROS_CDEFNAME(longjmp):
  75
  76     mov %rdi, %rax
  77         /* Make sure return value is not 0 */
  78         cmp $0,%rsi
  79         jne  1f
  80
  81         mov $1,%rsi
  82 1:
  83         /* Restore stack pointer and all registers from env */
  84         mov 120(%rax),%rsp /* Restore original stack */
  85
  86         mov 0(%rax),%rcx
  87         mov %rcx,retaddr(%rsp) /* Restore return address */
  88
  89         push %rsi /* Save return value on new stack */
  90
  91         /* Restore all registers */
  92         mov 8(%rax),%rbx /* %ebx */
  93         mov 16(%rax),%rcx /* %ecx */
  94         mov 24(%rax),%rdx /* %edx */
  95         mov 32(%rax),%rsi /* %esi */
  96         mov 40(%rax),%rdi /* %edi */
  97         mov 48(%rax),%rbp /* %ebp */
  98         mov 56(%rax),%r8
  99         mov 64(%rax),%r9
 100         mov 72(%rax),%r10
 101         mov 80(%rax),%r11
 102         mov 88(%rax),%r12
 103         mov 96(%rax),%r13
 104         mov 104(%rax),%r14
 105         mov 112(%rax),%r15
 106
 107         pop %rax /* Fetch return value */
 108         ret