source: mainline/kernel/arch/amd64/src/context.S@ e80329d6

#
# Copyright (c) 2001-2004 Jakub Jermar
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.text

.global context_save_arch
.global context_restore_arch

#include <arch/context_offset.h>

## Save current CPU context
#
# Save CPU context to context_t variable
# pointed by the 1st argument. Returns 1 in EAX.
#
context_save_arch:
        movq (%rsp), %rdx     # the caller's return %eip
        
        # 1st argument passed in %edi
        CONTEXT_SAVE_ARCH_CORE %rdi %rdx
        
        xorl %eax, %eax       # context_save returns 1
        incl %eax
        ret


## Restore current CPU context
#
# Restore CPU context from context_t variable
# pointed by the 1st argument. Returns 0 in EAX.
#
context_restore_arch:
        CONTEXT_RESTORE_ARCH_CORE %rdi %rdx
        
        movq %rdx, (%rsp)
        
        xorl %eax, %eax       # context_restore returns 0
        ret