user: 请从给定的汇编指令推导出C源代码：

```asm
<merge>:
  endbr64
  push   %rbp
  mov    %edx,%r9d
  sub    %edx,%ecx
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  mov    %rdi,%r14
  push   %r13
  mov    %ecx,%r13d
  push   %r12
  movslq %esi,%r12
  push   %rbx
  sub    %r12d,%r9d
  mov    %edx,%ebx
  lea    0x1(%r9),%r10d
  sub    $0x28,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,-0x38(%rbp)
  xor    %eax,%eax
  movslq %r10d,%rax
  mov    %rsp,%rcx
  lea    0xf(,%rax,4),%rax
  mov    %rax,%rdx
  and    $0xfffffffffffff000,%rax
  sub    %rax,%rcx
  and    $0xfffffffffffffff0,%rdx
  cmp    %rcx,%rsp
  je     L119
L223:
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  cmp    %rcx,%rsp
  jne    L223
L119:
  and    $0xfff,%edx
  sub    %rdx,%rsp
  test   %rdx,%rdx
  jne    L3
L199:
  movslq %r13d,%r15
  mov    %rsp,%rcx
  mov    %rsp,%r8
  lea    0xf(,%r15,4),%rax
  mov    %rax,%rdx
  and    $0xfffffffffffff000,%rax
  sub    %rax,%rcx
  and    $0xfffffffffffffff0,%rdx
  cmp    %rcx,%rsp
  je     L124
L222:
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  cmp    %rcx,%rsp
  jne    L222
L124:
  and    $0xfff,%edx
  sub    %rdx,%rsp
  test   %rdx,%rdx
  jne    L128
L39:
  mov    %rsp,%rcx
  test   %r10d,%r10d
  jle    L225
  mov    %r9d,%eax
  mov    %r8,%rdi
  mov    %r10d,-0x48(%rbp)
  lea    0x4(,%rax,4),%rdx
  movslq %r12d,%rax
  mov    %rcx,-0x50(%rbp)
  lea    (%r14,%rax,4),%rsi
  mov    %r9d,-0x44(%rbp)
  call   <memcpy@plt>
  test   %r13d,%r13d
  mov    -0x44(%rbp),%r9d
  mov    -0x50(%rbp),%rcx
  mov    -0x48(%rbp),%r10d
  mov    %rax,%r8
  jle    L80
  add    $0x1,%ebx
  mov    %rcx,%rdi
  mov    %r10d,-0x48(%rbp)
  add    $0x1,%r12d
  movslq %ebx,%rbx
  lea    0x0(,%r15,4),%rdx
  mov    %r9d,-0x44(%rbp)
  xor    %r15d,%r15d
  lea    (%r14,%rbx,4),%rsi
  mov    %rax,-0x50(%rbp)
  xor    %ebx,%ebx
  call   <memcpy@plt>
  mov    -0x44(%rbp),%r9d
  mov    -0x50(%rbp),%r8
  xor    %edx,%edx
  mov    -0x48(%rbp),%r10d
  mov    %rax,%rcx
  xor    %r11d,%r11d
  movslq %r12d,%rax
  nopw   0x0(%rax,%rax,1)
L20:
  mov    (%r8,%r15,4),%edi
  mov    (%rcx,%r11,4),%esi
  cmp    %esi,%edi
  jg     L173
L166:
  mov    %edi,-0x4(%r14,%rax,4)
  movslq %eax,%r12
  lea    0x1(%rdx),%r15d
  add    $0x1,%rax
  cmp    %edx,%r9d
  jle    L36
  cmp    %ebx,%r13d
  jle    L36
  movslq %r15d,%r15
  mov    (%rcx,%r11,4),%esi
  mov    (%r8,%r15,4),%edi
  mov    %r15,%rdx
  cmp    %esi,%edi
  jle    L166
L173:
  add    $0x1,%ebx
  mov    %esi,-0x4(%r14,%rax,4)
  movslq %eax,%r12
  add    $0x1,%rax
  cmp    %ebx,%r13d
  jle    L158
  cmp    %edx,%r10d
  jle    L158
  movslq %ebx,%r11
  jmp    L20
  xchg   %ax,%ax
L3:
  orq    $0x0,-0x8(%rsp,%rdx,1)
  jmp    L199
  nopl   0x0(%rax,%rax,1)
L158:
  mov    %edx,%r15d
L36:
  cmp    %r15d,%r10d
  mov    %r10d,-0x44(%rbp)
  jle    L102
  movslq %r12d,%rax
  sub    %r15d,%r9d
  mov    %rcx,-0x50(%rbp)
  lea    (%r14,%rax,4),%rdi
  movslq %r15d,%rax
  lea    0x4(,%r9,4),%rdx
  lea    (%r8,%rax,4),%rsi
  call   <memcpy@plt>
  mov    -0x44(%rbp),%r10d
  mov    -0x50(%rbp),%rcx
  add    %r12d,%r10d
  sub    %r15d,%r10d
  movslq %r10d,%r12
L102:
  cmp    %ebx,%r13d
  jle    L108
L210:
  sub    $0x1,%r13d
  lea    (%r14,%r12,4),%rdi
  sub    %ebx,%r13d
  movslq %ebx,%rbx
  lea    0x4(,%r13,4),%rdx
  lea    (%rcx,%rbx,4),%rsi
  call   <memcpy@plt>
L108:
  mov    -0x38(%rbp),%rax
  sub    %fs:0x28,%rax
  jne    L138
  lea    -0x28(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
L225:
  test   %r13d,%r13d
  jle    L80
  add    $0x1,%ebx
  mov    %rcx,%rdi
  lea    0x0(,%r15,4),%rdx
  movslq %ebx,%rbx
  lea    (%r14,%rbx,4),%rsi
  xor    %ebx,%ebx
  call   <memcpy@plt>
  mov    %rax,%rcx
  jmp    L210
  nopw   0x0(%rax,%rax,1)
L80:
  xor    %ebx,%ebx
  xor    %r15d,%r15d
  jmp    L36
L128:
  orq    $0x0,-0x8(%rsp,%rdx,1)
  jmp    L39
L138:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
void merge(int *a, int left, int mid, int right) {
  int i, j, k;
  int n1, n2;
  n1 = mid - left + 1;
  n2 = right - mid;
  int left_arr[n1], right_arr[n2];
  i = 0;
  j = 0;
  for (i = 0; i < n1; i++) {
    left_arr[i] = a[left + i];
  }
  for (j = 0; j < n2; j++) {
    right_arr[j] = a[mid + 1 + j];
  }
  i = 0;
  j = 0;
  k = left;
  while (i < n1 && j < n2) {
    if (left_arr[i] <= right_arr[j]) {
      a[k] = left_arr[i];
      i++;
    } else {
      a[k] = right_arr[j];
      j++;
    }
    k++;
  }
  while (i < n1) {
    a[k] = left_arr[i];
    k++;
    i++;
  }
  while (j < n2) {
    a[k] = right_arr[j];
    k++;
    j++;
  }
  return;
}
```