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/* in i386, generally used stack for argument passing. */
/* use register for return : %eax */
/* no need save registers */
/* stack frame (with -pg): parent addr = 4(%ebp) */
/* child addr = (%esp) */
#include "utils/asm.h"
GLOBAL(mcount)
sub $32, %esp
/* save registers */
movl %edx, 28(%esp)
movl %ecx, 24(%esp)
movl %eax, 20(%esp)
movl $0, 16(%esp)
/* parent location */
leal 4(%ebp), %eax
movl %eax, 0(%esp)
/* child addr */
movl 32(%esp), %eax
movl %eax, 4(%esp)
/* mcount_regs */
leal 16(%esp), %eax
movl %eax, 8(%esp)
call mcount_entry
/* restore registers */
movl 20(%esp), %eax
movl 24(%esp), %ecx
movl 28(%esp), %edx
add $32, %esp
ret
END(mcount)
ENTRY(mcount_return)
sub $16, %esp
movl %edx, 8(%esp)
movl %eax, 4(%esp)
leal 4(%esp), %eax
movl %eax, 0(%esp)
/* returns original parent address */
call mcount_exit
movl %eax, 12(%esp)
movl 4(%esp), %eax
movl 8(%esp), %edx
add $12, %esp
ret
END(mcount_return)
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