source: mainline/kernel/arch/ia32/src/context.S@ c7fbb90

#
# Copyright (c) 2001-2004 Jakub Jermar
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#include <arch/context_offset.h>

.text

.global context_save_arch
.global context_restore_arch


## Save current CPU context
#
# Save CPU context to the context_t variable
# pointed by the 1st argument. Returns 1 in EAX.
#
context_save_arch:
        movl 0(%esp),%eax       # save pc value into eax        
        movl 4(%esp),%edx       # address of the context variable to save context to 

                # save registers to given structure
        CONTEXT_SAVE_ARCH_CORE %edx %eax

        xorl %eax,%eax          # context_save returns 1
        incl %eax
        ret


## Restore saved CPU context
#
# Restore CPU context from context_t variable
# pointed by the 1st argument. Returns 0 in EAX.
#
context_restore_arch:
        movl 4(%esp),%eax       # address of the context variable to restore context from

                # restore registers from given structure
        CONTEXT_RESTORE_ARCH_CORE %eax %edx

        movl %edx,0(%esp)       # put saved pc on stack
        xorl %eax,%eax          # context_restore returns 0
        ret