kernel-ark/arch/um/sys-i386/setjmp.S
Jeff Dike 13c06be399 [PATCH] uml: Use klibc setjmp/longjmp
This patch adds an implementation of setjmp and longjmp to UML, allowing
access to the inside of a jmpbuf without needing the access macros formerly
provided by libc.

The implementation is stolen from klibc.  I copy the relevant files into
arch/um.  I have another patch which avoids the copying, but requires klibc be
in the tree.

setjmp and longjmp users required some tweaking.  Includes of <setjmp.h> were
removed and includes of the UML longjmp.h were added where necessary.  There
are also replacements of siglongjmp with UML_LONGJMP which I somehow missed
earlier.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:05 -07:00

59 lines
963 B
ArmAsm

#
# arch/i386/setjmp.S
#
# setjmp/longjmp for the i386 architecture
#
#
# The jmp_buf is assumed to contain the following, in order:
# %ebx
# %esp
# %ebp
# %esi
# %edi
# <return address>
#
.text
.align 4
.globl setjmp
.type setjmp, @function
setjmp:
#ifdef _REGPARM
movl %eax,%edx
#else
movl 4(%esp),%edx
#endif
popl %ecx # Return address, and adjust the stack
xorl %eax,%eax # Return value
movl %ebx,(%edx)
movl %esp,4(%edx) # Post-return %esp!
pushl %ecx # Make the call/return stack happy
movl %ebp,8(%edx)
movl %esi,12(%edx)
movl %edi,16(%edx)
movl %ecx,20(%edx) # Return address
ret
.size setjmp,.-setjmp
.text
.align 4
.globl longjmp
.type longjmp, @function
longjmp:
#ifdef _REGPARM
xchgl %eax,%edx
#else
movl 4(%esp),%edx # jmp_ptr address
movl 8(%esp),%eax # Return value
#endif
movl (%edx),%ebx
movl 4(%edx),%esp
movl 8(%edx),%ebp
movl 12(%edx),%esi
movl 16(%edx),%edi
jmp *20(%edx)
.size longjmp,.-longjmp