setjmp.s

来自「glibc 库, 不仅可以学习使用库函数,还可以学习函数的具体实现,是提高功力的」· S 代码 · 共 82 行

/* setjmp for s390, ELF version.
   Copyright (C) 2000, 2002, 2005 Free Software Foundation, Inc.
   Contributed by Martin Schwidefsky ([e-mail]).
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <sysdep.h>
#define _ASM
#define _SETJMP_H
#include <bits/setjmp.h>

	/* We include the BSD entry points here as well but we make
	   them weak.  */
ENTRY (setjmp)
	.weak C_SYMBOL_NAME (setjmp)
	lhi    %r3,1                /* second argument of one */
	j      .Linternal_sigsetjmp /* branch relativ to __sigsetjmp */
END (setjmp)

	/* Binary compatibility entry point.  */
ENTRY(_setjmp)
	.weak  C_SYMBOL_NAME (_setjmp)
	lhi    %r3,0                /* second argument of zero */
	j      .Linternal_sigsetjmp /* branch relativ to __sigsetjmp */
END (_setjmp)
libc_hidden_def (_setjmp)

ENTRY(__setjmp)
	lhi    %r3,0                /* second argument of zero */
	j      .Linternal_sigsetjmp /* branch relativ to __sigsetjmp */
END (__setjmp)

ENTRY(__sigsetjmp)
.Linternal_sigsetjmp:
#ifdef PTR_MANGLE
	stm    %r6,%r13,0(%r2)      /* store registers in jmp_buf */
	lr     %r4,%r14
	lr     %r5,%r15
	PTR_MANGLE (%r4, %r1)
	PTR_MANGLE2 (%r5, %r1)
	stm    %r4,%r5,32(%r2)
#else
	stm    %r6,%r15,0(%r2)      /* store registers in jmp_buf */
#endif
	std    %f4,40(%r2)
	std    %f6,48(%r2)
#if defined NOT_IN_libc && defined IS_IN_rtld
	/* In ld.so we never save the signal mask.  */
	lhi    %r2,0
	br     %r14
#elif defined PIC
	/* We cannot use the PLT, because it requires that %r12 be set, but
	   we can't save and restore our caller's value.  Instead, we do an
	   indirect jump through the GOT. */
	basr   %r1,0
.L0:    al     %r1,.L1 - .L0(0,%r1) /* get address of global offset table */
				    /* get address of __sigjmp_save from got */
	l      %r1,__sigjmp_save@GOT12(0,%r1)
	br     %r1
.L1:    .long  _GLOBAL_OFFSET_TABLE_ - .L0
#else
	basr   %r1,0
.L0:    l      %r1,.L1-.L0(0,%r1)   /* load address of __sigjmp_save */
	br     %r1                  /* tail-call __sigjmp_save */
.L1:    .long  __sigjmp_save
#endif
END (__sigsetjmp)