Question

和原来一样，只是传递参数时不使用栈而使用寄存器。

6.3.1 MSVC

#!bash
_DATA   SEGMENT
$SG1289 DB ’Enter X:’, 0aH, 00H
$SG1291 DB ’%d’, 00H
$SG1292 DB ’You entered %d...’, 0aH, 00H
_DATA   ENDS

_TEXT   SEGMENT
x$ = 32
main    PROC
$LN3:
        sub rsp, 56
        lea rcx, OFFSET FLAT:$SG1289 ; ’Enter X:’
        call printf
        lea rdx, QWORD PTR x$[rsp]
        lea rcx, OFFSET FLAT:$SG1291 ; ’%d’
        call scanf
        mov edx, DWORD PTR x$[rsp]
        lea rcx, OFFSET FLAT:$SG1292 ; ’You entered %d...’
        call printf
        ; return 0
        xor eax, eax
        add rsp, 56
        ret 0
main    ENDP
_TEXT   ENDS

6.3.2 GCC

#!bash
.LC0:
        .string "Enter X:"
.LC1:
        .string "%d"
.LC2:
        .string "You entered %d...
"
main:
        sub     rsp, 24
        mov     edi, OFFSET FLAT:.LC0 ; "Enter X:"
        call    puts
        lea     rsi, [rsp+12]
        mov     edi, OFFSET FLAT:.LC1 ; "%d"
        xor     eax, eax
        call    __isoc99_scanf
        mov     esi, DWORD PTR [rsp+12]
        mov     edi, OFFSET FLAT:.LC2 ; "You entered %d...
"
        xor     eax, eax
        call    printf
        ; return 0
        xor     eax, eax
        add     rsp, 24
        ret