So for one question in my hw, I have this assembly code that ultimately I have t

Question

So for one question in my hw, I have this assembly code that ultimately I have to implement in C.

/*p1 in %rdi, p2 in %rsi, action in %edx
.L8: MODE_E
movl $27, %eax
ret

.L3: MODE_A
movq (%rsi), %rax
movq (%rdi), %rax
movq %rdx, (%rsi)

.L5: MODE_B
movq (%rdi), %rax
addq (%rsi), %rax
movq %rax, (%rdi)
ret

.L6: MODE_C
movq $59, (%rdi)
movq (%rsi), %rax

.L7: MODE_D
movq (%rsi),%rax
movq %rax, (%rdi)
movl $27, %eax

.L9: DEFAULT
movl $12, %eax
ret

Now, for the code in C this is what I ended up with, could someone check if it is right please? and if not, explain why?

typedef enum {MODE_A, MODE_B, MODE_C, MODE_D, MODE_E} mode_t;

long switch3(long *p1, long *p2, mode_t action)
{

long result =0;
switch (action)

{

case MODE_A:
result = *p2;
temp = *p1 //quite unsure about this part of the assembly
*p2 = p1

case MODE_B:
result = *p1
result += p2
*p1 = result
break

case MODE_C:
*p1 = 59
result = *p2
break

case MODE_D:
result = *p2
*p1 = result
result = 27
break

case MODE_E:
result = 27
break

default:
result = 12
break

}

return result;

}

Explanation / Answer

I made little changes in your existing program Typedef enum {MODE_A, MODE_B, MODE_C, MODE_D, MODE_E} mode_t; int switch3(int *p1,int *p2,mode_t action) { int result = 0; switch(action){ case MODE_A: result = *p1; *p1 = *p2; break; case MODE_B: result = *p1 + *p2; *p2 = result; break; case MODE_C: *p2 = 59; result = *p1; break; case MODE_D: *p2 = *p1; result = 27; break; case MODE_E: result = 27; break; default: result = 12; break; } return result; }

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