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Diffstat (limited to 'sysdeps/vax/__longjmp.c')
| -rw-r--r-- | sysdeps/vax/__longjmp.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/sysdeps/vax/__longjmp.c b/sysdeps/vax/__longjmp.c new file mode 100644 index 0000000000..0ee040ab25 --- /dev/null +++ b/sysdeps/vax/__longjmp.c @@ -0,0 +1,100 @@ +/* Copyright (C) 1991, 1992, 1994 Free Software Foundation, Inc. + Derived from @(#)_setjmp.s 5.7 (Berkeley) 6/27/88, + Copyright (c) 1980 Regents of the University of California. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Library General Public License as +published by the Free Software Foundation; either version 2 of the +License, or (at your option) any later version. + +The GNU C Library is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Library General Public License for more details. + +You should have received a copy of the GNU Library General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#include <ansidecl.h> +#include <setjmp.h> + +#ifndef __GNUC__ + #error This file uses GNU C extensions; you must compile with GCC. +#endif + + +#define REI 02 /* Vax `rei' opcode. */ + +/* Jump to the position specified by ENV, causing the + setjmp call there to return VAL, or 1 if VAL is 0. */ +__NORETURN +void +DEFUN(__longjmp, (env, val), CONST __jmp_buf env AND int val) +{ + register long int *fp asm("fp"); + long int *regsave; + unsigned long int flags; + + if (env.__fp == NULL) + __libc_fatal("longjmp: Invalid ENV argument.\n"); + + if (val == 0) + val = 1; + + asm volatile("loop:"); + + flags = *(long int *) (6 + (char *) fp); + regsave = (long int *) (20 + (char *) fp); + if (flags & 1) + /* R0 was saved by the caller. + Store VAL where it will be restored from. */ + *regsave++ = val; + if (flags & 2) + /* R1 was saved by the caller. + Store ENV where it will be restored from. */ + *regsave = env; + + /* Was the FP saved in the last call the same one in ENV? */ + asm volatile("cmpl %0, 12(fp);" + /* Yes, return to it. */ + "beql done;" + /* The FP in ENV is less than the one saved in the last call. + This means we have already returned from the function that + called `setjmp' with ENV! */ + "blssu latejump;" : /* No outputs. */ : "g" (env.__fp)); + + /* We are more than one level below the state in ENV. + Return to where we will pop another stack frame. */ + asm volatile("movl $loop, 16(fp);" + "ret"); + + asm volatile("done:"); + { + char return_insn asm("*16(fp)"); + if (return_insn == REI) + /* We're returning with an `rei' instruction. + Do a return with PSL-PC pop. */ + asm volatile("movab 0f, 16(fp)"); + else + /* Do a standard return. */ + asm volatile("movab 1f, 16(fp)"); + + /* Return. */ + asm volatile("ret"); + } + + asm volatile("0:" /* `rei' return. */ + /* Compensate for PSL-PC push. */ + "addl2 %0, sp;" + "1:" /* Standard return. */ + /* Return to saved PC. */ + "jmp %1" : /* No outputs. */ : + "g" (8), "g" (env.__pc)); + + /* Jump here when the FP saved in ENV points + to a function that has already returned. */ + asm volatile("latejump:"); + __libc_fatal("longjmp: Attempt to jump to a function that has returned.\n"); +} |