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
__longjmp(__jmp_buf env,int val)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 }
83