user: What would the C source look like for the assembly code provided here:

```asm
<merge_sort_helper>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  push   %r13
  movslq %edx,%r13
  push   %r12
  push   %rbx
  sub    $0x38,%rsp
  mov    %fs:0x28,%rax
  mov    %rax,-0x38(%rbp)
  xor    %eax,%eax
  cmp    %r13d,%esi
  jl     L168
L134:
  mov    -0x38(%rbp),%rax
  sub    %fs:0x28,%rax
  jne    L38
  lea    -0x28(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
  xchg   %ax,%ax
L168:
  mov    %r13d,%eax
  mov    %rdi,%r12
  mov    %esi,%ebx
  mov    %rsp,-0x50(%rbp)
  sub    %esi,%eax
  mov    %eax,%r10d
  mov    %eax,-0x44(%rbp)
  sar    %r10d
  add    %esi,%r10d
  mov    %r10d,%edx
  mov    %r10d,-0x58(%rbp)
  call   <merge_sort_helper>
  mov    -0x58(%rbp),%r10d
  mov    %r13d,%edx
  mov    %r12,%rdi
  lea    0x1(%r10),%r14d
  mov    %r14d,%esi
  mov    %r14d,%r15d
  call   <merge_sort_helper>
  mov    -0x44(%rbp),%r10d
  mov    %rsp,%rcx
  lea    0x1(%r10),%eax
  mov    -0x58(%rbp),%r10d
  cltq
  lea    0xf(,%rax,4),%rax
  mov    %rax,%rdx
  and    $0xfffffffffffff000,%rax
  sub    %rax,%rcx
  and    $0xfffffffffffffff0,%rdx
  cmp    %rcx,%rsp
  je     L112
L29:
  sub    $0x1000,%rsp
  orq    $0x0,0xff8(%rsp)
  cmp    %rcx,%rsp
  jne    L29
L112:
  and    $0xfff,%edx
  sub    %rdx,%rsp
  test   %rdx,%rdx
  jne    L170
L6:
  mov    %rsp,%r8
  cmp    %r10d,%ebx
  jg     L119
  cmp    %r13d,%r14d
  jg     L119
  mov    $0x1,%eax
  movslq %ebx,%r11
  movslq %r14d,%rdi
  nopl   0x0(%rax)
L15:
  mov    (%r12,%r11,4),%esi
  mov    (%r12,%rdi,4),%edx
  mov    %eax,%ecx
  cmp    %edx,%esi
  jge    L60
L5:
  mov    %esi,-0x4(%r8,%rax,4)
  add    $0x1,%ebx
  add    $0x1,%rax
  cmp    %r15d,%r13d
  jl     L10
  cmp    %r10d,%ebx
  jg     L10
  movslq %ebx,%r11
  mov    (%r12,%rdi,4),%edx
  mov    %eax,%ecx
  mov    (%r12,%r11,4),%esi
  cmp    %edx,%esi
  jl     L5
L60:
  add    $0x1,%r15d
  mov    %edx,-0x4(%r8,%rax,4)
  add    $0x1,%rax
  cmp    %r13d,%r15d
  jg     L10
  cmp    %ebx,%r10d
  jl     L102
  movslq %r15d,%rdi
  jmp    L15
L119:
  xor    %ecx,%ecx
  nopl   0x0(%rax,%rax,1)
L10:
  cmp    %ebx,%r10d
  jl     L102
  movslq %ecx,%rax
  sub    %ebx,%r10d
  mov    %ecx,-0x48(%rbp)
  lea    (%r8,%rax,4),%rdi
  movslq %ebx,%rax
  lea    0x4(,%r10,4),%rdx
  mov    %r8,-0x58(%rbp)
  lea    (%r12,%rax,4),%rsi
  call   <memcpy@plt>
  mov    -0x48(%rbp),%ecx
  mov    -0x58(%rbp),%r8
  lea    (%r14,%rcx,1),%r9d
  mov    %r9d,%ecx
  sub    %ebx,%ecx
L102:
  cmp    %r15d,%r13d
  jl     L157
  mov    %r13d,%eax
  movslq %ecx,%rcx
  mov    %r8,-0x58(%rbp)
  sub    %r15d,%eax
  movslq %r15d,%r15
  lea    (%r8,%rcx,4),%rdi
  lea    0x4(,%rax,4),%rdx
  lea    (%r12,%r15,4),%rsi
  call   <memcpy@plt>
  mov    -0x58(%rbp),%r8
L157:
  movslq -0x44(%rbp),%r14
  mov    %r14,%rax
  lea    0x4(,%r14,4),%rdx
  neg    %rax
  shl    $0x2,%rax
  lea    (%rax,%r13,4),%rdi
  lea    (%rax,%r14,4),%rsi
  add    %r12,%rdi
  add    %r8,%rsi
  call   <memcpy@plt>
  mov    -0x50(%rbp),%rsp
  jmp    L134
  nopw   0x0(%rax,%rax,1)
L170:
  orq    $0x0,-0x8(%rsp,%rdx,1)
  jmp    L6
L38:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
void merge_sort_helper(int *arr, int left, int right) {
  int mid;
  if (left < right) {
    mid = left + (right - left) / 2;
    merge_sort_helper(arr, left, mid);
    merge_sort_helper(arr, mid + 1, right);
    int temp[right - left + 1], i = left, j = mid + 1, k = 0, m;
    while ((i <= mid) && (j <= right)) {
      if (arr[i] < arr[j]) {
        temp[k] = arr[i];
        i++;
        k++;
      } else {
        temp[k] = arr[j];
        j++;
        k++;
      }
    }
    while (i <= mid) {
      temp[k] = arr[i];
      k++;
      i++;
    }
    while (j <= right) {
      temp[k] = arr[j];
      k++;
      j++;
    }
    for (m = right - left; m >= 0; m--) {
      arr[right] = temp[m];
      right--;
    }
  }
}
```