使用汇编程序时 Debug/Release 操作的区别

我从汇编模块导入一个函数，在调试中一切正常，但在发布中一切都停止工作。我不明白为什么。主程序用C++（Visual Studio 2019）编写，汇编模块由MASM编译。

主程序(C++)

#include <iostream>

void print(short** arr, const short m, const short n);
void print_vec(short* v, const int n);
extern "C" void __cdecl mat_vec_mul(short** mat, short* vec, short* vec_res, const short m, const short n);

int main()
{
    const short M = 3;
    const short N = 2;

    short** matrix = new short* [M];
    short* vec = new short [N];

    for (short i = 0; i < N; i++)
    {
        vec[i] = i + 1;
    }

    short* vec_res = new short [M];

    for (short i = 0, el = 1; i < M; i++)
    {
        matrix[i] = new short[N];
        for (short j = 0; j < N; j++, el++)
        {
            matrix[i][j] = el;
        }
    }

    std::cout << "Source matrix" << std::endl;
    print(matrix, M, N);
    std::cout << "\nSource vector" << std::endl;
    print_vec(vec, N);

    //prototype of mul in c++
    //for (short i = 0; i < M; i++)
    //{
    //  vec_res[i] = 0;
    //  for (short j = 0; j < N; j++)
    //  {
    //      vec_res[i] += matrix[i][j] * vec[j];
    //  }
    //}

    mat_vec_mul(matrix, vec, vec_res, M, N);

    std::cout << "\n\nResult vector" << std::endl;
    print_vec(vec_res, M);



    delete[]vec;
    delete[]vec_res;

    for (short i = 0; i < M; i++)
    {
        delete[]matrix[i];
    }
    delete[]matrix;


    std::cin.get();
    std::cin.get();
    return 0;
}

void print(short** arr, const short m, const short n)
{
    for (short i = 0; i < m; i++)
    {
        for (short j = 0; j < n; j++)
        {
            std::cout << arr[i][j];
            if (j != n - 1)
                std::cout << " ";
        }
        std::cout << std::endl;
    }
}

void print_vec(short* v, const int n)
{
    for (short i = 0; i < n; i++)
    {
        std::cout << v[i];
        if (i != n - 1)
            std::cout << " ";
    }

}

连接文件mat_vec_mul.asm的代码

.686P
.model flat, C

.data
    small_size = 2
    ptr_size = 4
    msize dw 0
    nsize dw 0
.data?
    i dw ?
.code
public mat_vec_mul 
mat_vec_mul proc near
    push ebp
    mov ebp, esp

    mat equ dword ptr [ebp+8]
    vec equ dword ptr [ebp+12]
    vec_r equ dword ptr [ebp+16]
    m equ dword ptr [ebp+20]
    n equ dword ptr [ebp+24]

    xor ecx, ecx
    xor eax, eax

    mov eax, m
    mov ecx, dword ptr ptr_size
    imul ecx
    mov dword ptr msize, eax
    xor eax, eax

    mov eax, n
    mov ecx, dword ptr small_size
    imul ecx
    mov dword ptr nsize, eax
    xor eax, eax
    xor ecx, ecx

    ;mov ecx, m

    xor ebx, ebx
    mov ebx, mat

    xor esi, esi
    mov esi, vec_r

    ;xor edi, edi
    ;mov edi, vec


    .repeat 
        mov dword ptr i, ecx
        ;mov eax, dword ptr [esi]
        mov word ptr [esi], 0

        xor edi, edi
        mov edi, vec

        xor ecx, ecx
        .while (ecx < dword ptr nsize)
            
            ;ebx=i;ecx=j
            mov eax, dword ptr [ebx]
            mov ax, word ptr [eax+ecx]
            mov dx, word ptr [edi]
            ;mov dx, word ptr [edx]
            imul dx;dx:ax = mul

            xor edx, edx
            ;mov edx, dword ptr [esi]
            ;mov [edx], ax

            add word ptr [esi], ax

            
            add ecx, small_size
            add edi, small_size
            
        .endw 


        mov ecx, dword ptr i
        add ecx, ptr_size

        ;mov eax, dword ptr ptr_size
        add esi, small_size
        add ebx, ptr_size
        xor eax, eax
        
    .until (cx >= word ptr msize)

exit:
    xor esi, esi
    xor edi, edi
    xor ecx, ecx
    xor ebx, ebx
    pop ebp
    ret
mat_vec_mul endp
end

在 Release 的第 86 行，抛出了一个 nullptr 异常。vec_res 是空的，但一切都在调试中工作。