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我想将此合并排序代码(请参见下文)嵌入到我的 C++ 程序(也请参见下文)中,以便我可以在使用汇编的程序中进行合并排序。是的,我知道我可以在 C++ 中编写合并排序,但是我嵌入这个程序集是非常重要的。

合并排序代码:

%include "io.mac"

.DATA
MAX_SIZE EQU 25
%define ARR_LEN dword [n]

PROMPT_ENTER_ARR_LEN db "Enter size of your Array : ", 0
PROMPT_ENTER_ELEMENTS db    "Please enter elements of your array : ", 0
print_orig_array db "Original Array ", 0
print_final_array   db  "Sorted Array ", 0
print_space db " ",0
merge_sort_debug_str db "Merge Sort Params: EAX, ECX: ", 0
merge_sort_end_debug_str db "End Merge Sort", 0
merge_debug_str db "Merge Params: EAX, EBX, ECX, EDX, EDI: ", 0
copy_debug_str db "Copy Params: EAX, EBX, ECX: ", 0
temp_array_debug_str db "Temp array: ", 0
merge_copy_back_temp_debug_str db "Merge Copy back temp array: ", 0
.UDATA
;; Length of the array
n       resd 1
;; Array to be sorted
arr   resd MAX_SIZE
;; Temporary storage array
temp_arr resd MAX_SIZE
.CODE
.STARTUP

READ_ARR_LEN:
;; Read the length of the array
PutStr PROMPT_ENTER_ARR_LEN
nwln
GetLInt [n]     ; Size of input array
PutLInt [n]
nwln

GET_ARRAY:
;; Get values in arr from the user
mov   EAX, arr
mov   ECX, ARR_LEN
call  Read_Arr

;; Print the original array
mov   ECX, ARR_LEN
PutStr print_orig_array
call  Print_Arr

;; Run Merge Sort on the array
mov   EAX, arr
mov   EBX, temp_arr
mov   ECX, ARR_LEN
call  Merge_Sort

;; Print the final array
PutStr print_final_array
call  Print_Orig_Arr
.EXIT

Merge_Sort:
;; EAX - Array start
;; ECX - array length

;; Arrays of size 0 or 1 are already sorted
cmp   ECX, 2
jl    Trivial_Merge_Sort

;; Merge_Sort (first half)
;; Length of the first half
;; ECX /= 2
push  ECX
shr   ECX, 1
call  Merge_Sort
pop   ECX

;; Merge_Sort (second half)
push  EAX
push  EBX
push  ECX

;; Length of the second half
;; ECX = ECX - ECX/2
mov   EDX, ECX
shr   EDX, 1
sub   ECX, EDX
imul  EDX, 4
;; Start index of the second half
;; EAX = EAX + (ECX/2) * 4
add   EAX, EDX
push  EDX
call  Merge_Sort
pop   EDX

pop   ECX
pop   EBX
pop   EAX

pushad
;; Merge (first half, second half)
;; Length of first half = ECX/2
;; Length of second half = ECX - ECX/2
mov   EDX, ECX
shr   ECX, 1
sub   EDX, ECX

;; Start of second half = EAX + (ECX/2) * 4
mov   EBX, EAX
mov   EDI, ECX
imul  EDI, 4
add   EBX, EDI
;; Index of temp array = 0
sub   EDI, EDI
call  Merge
popad

;; Copy back the merged array from temp_arr to arr
call  Merge_Copy_Back_Temp

ret

Trivial_Merge_Sort:
;; In case of arrays of length 0 or 1
ret

Merge:
;; Merge two arrays contents.
;; The final merged array will be in temp_arr
;; Merging is done recursively.

;; Arguments:
;; EAX - First array's start
;; EBX - Second array's start
;; ECX - Length of first array
;; EDX - Length of second array
;; EDI - Index in temp array
pushad

;; Handle the cases where one array is empty
cmp   ECX, 0
jz    First_Array_Over
cmp   EDX, 0
jz    Second_Array_Over

;; Compare first elements of both the arrays
push  EDX
push  EDI
mov   EDX, [EAX]
mov   EDI, [EBX]
cmp   EDX, EDI
pop   EDI
pop   EDX

;; Pick which ever is the least and update that array
jl    Update_First_Array
jmp   Update_Second_Array

Update_First_Array:
;; min_elem = min (first elements of first array and second array)
;; Put min_elem into the temp array
push  dword [EAX]
pop   dword [temp_arr + EDI * 4]
add   EAX, 4
dec   ECX
inc   EDI

;; Recursively call Merge on the updated array and the
;; other array
call  Merge
popad
ret

Update_Second_Array:
;; min_elem = min (first elements of first array and second array)
;; Put min_elem into the temp array
push  dword [EBX]
pop   dword [temp_arr + EDI * 4]
add   EBX, 4
dec   EDX
inc   EDI

;; Recursively call Merge on the updated array and the
;; other array
call  Merge
popad
ret

Merge_Copy_Back_Temp:
;; Copy back the temp array into original array
;; Arguments:
;; EAX - original array address
;; ECX - original array length
pushad

;; For copying back, the destination array is EAX
mov   EBX, EAX
;; Now, the source array is temp_arr
mov   EAX, temp_arr
call  Copy_Array
popad
ret

Trivial_Merge:
;; Note: One array is empty means no need to merge.
popad
ret

First_Array_Over:
;; Copy the rest of the second array to the temp arr
;; because the first array is empty
pushad
mov   EAX, EBX
mov   ECX, EDX
mov   EBX, temp_arr
imul  EDI, 4
add   EBX, EDI
call  Copy_Array
popad
popad
ret

Second_Array_Over:
;; Copy the rest of the first array to the temp arr
;; because the second array is empty
pushad
mov   EBX, temp_arr
imul  EDI, 4
add   EBX, EDI
call  Copy_Array
popad
popad
ret

Copy_Array:
;; Copy array to destination array
;; EAX - Array start
;; EBX - Destination array
;; ECX - Array length

;; Trivial case
cmp   ECX, 0
jz    Copy_Empty_Array

push  ECX
sub   EDI, EDI
copy_loop:
;; Copy each element
push  dword [EAX + EDI * 4]
pop   dword [EBX + EDI * 4]
inc   EDI
loop  copy_loop

pop   ECX
ret

Copy_Empty_Array:
ret

Read_Arr:
;; EAX - array start
;; ECX - array length
PutStr PROMPT_ENTER_ELEMENTS
nwln
mov   ESI, EAX
sub   EDI, EDI
loop1:
;; Read each element
GetLInt [ESI + EDI * 4]
inc   EDI
loop  loop1
ret

Print_Temp_Arr:
;; Print contents of temp_arr (for debugging)
pushad
mov EAX, temp_arr
mov ECX, ARR_LEN
call Print_Arr
popad
ret

Print_Orig_Arr:
;; Print contents of arr (for debugging)
pushad
mov EAX, arr
mov ECX, ARR_LEN
call Print_Arr
popad
ret

Print_Arr:
;; Print contents of an array
;; EAX - Array start
;; ECX - array length
nwln
mov   ESI, EAX
sub   EDI, EDI
new_loop1:
PutLInt [ESI + EDI * 4]
PutStr print_space
inc   EDI
loop  new_loop1
nwln
ret

C++ 代码:

#include <iostream>
#include <cmath>
#include <stdio.h>

using namespace std;

int main()
{
   //insert assembly code here
   return 0;
}
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