Recursive implementation of assembly language learning series

If the assembly language to achieve the following C language functions, the compilation environment Ubuntu14.04 (32-bit).

#include <stdio.h>intRefact (intN) {    if(n = =1)        return 1; Else        returnn * refact (N-1);}intMain () {intA =4; printf ("%d\n", Refact (a)); return 0;}

For both recursive and cyclic implementations, the assembly is converted to a jump statement implementation. You can convert the above code to

refact:     if ((n10)    gotodone;     body-statement        done:

• Assembly Code REFACT.S

. Section. DataA:.int 4        format:. Asciz"%d\n". Section. Text.global _start_start:PUSHL%ebp movl%esp,%EBP Subl $8,%ESP #allocate storage space movl A,%edx #get a movl%edx, (%ESP) #save value of a on S TackPagerrefact pushl%eax pushl $formatPagerprintf MOVL $0, (%ESP)PagerExitrefact:PUSHL%ebp movl%esp,%EBP pushl%ebx Subl $4,%ESP #allocate storage space MOVL8(%EBP),%EBX #get n Cmpl $1,%EBXJleDone #Test(n1) >=0Leal-1(%EBX),%eax # (n1) Movl%eax, (%ESP) #save (n-1) on the stackPagerrefactImul%ebx,%eax #use%eax to save resultDone :Addl $4,%esp #release space popl%ebx popl%ebpret        

• Compile

As Refact.s-o REFACT.O

• Link

Ld-lc-i/lib/ld-linux.so.2 Refact.o-o Refact

• Perform

./refact

Recursive implementation of assembly language learning series