user: What is the c source code of the assembly code below:

```asm
<partition>:
  endbr64
  cmp    %esi,%edi
  jl     L62
  ret
  nopl   0x0(%rax)
L62:
  lea    (%rdi,%rsi,1),%eax
  push   %r15
  push   %r14
  push   %r13
  mov    %eax,%r13d
  push   %r12
  shr    $0x1f,%r13d
  mov    %esi,%r12d
  push   %rbp
  add    %eax,%r13d
  mov    %edi,%ebp
  push   %rbx
  sar    %r13d
  sub    $0x18,%rsp
  cmp    %r13d,%edi
  jge    L143
  lea    (%rdi,%r13,1),%eax
  mov    %eax,%r14d
  shr    $0x1f,%r14d
  add    %eax,%r14d
  sar    %r14d
  cmp    %r14d,%edi
  jl     L101
  lea    0x1(%r14),%ebx
  cmp    %ebx,%r13d
  jg     L96
L76:
  mov    %r13d,%edx
  mov    %r14d,%esi
  mov    %ebp,%edi
  call   <merge@plt>
L143:
  lea    0x1(%r13),%r15d
  cmp    %r12d,%r15d
  jge    L33
  lea    (%r15,%r12,1),%eax
  mov    %eax,%r14d
  shr    $0x1f,%r14d
  add    %eax,%r14d
  sar    %r14d
  cmp    %r14d,%r15d
  jl     L59
  lea    0x1(%r14),%r8d
  cmp    %r8d,%r12d
  jg     L61
L147:
  mov    %r12d,%edx
  mov    %r14d,%esi
  mov    %r15d,%edi
  call   <merge@plt>
L33:
  add    $0x18,%rsp
  mov    %r12d,%edx
  mov    %r13d,%esi
  mov    %ebp,%edi
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  jmp    1050 <merge@plt>
  nopl   0x0(%rax)
L61:
  lea    (%r12,%r8,1),%eax
  mov    %eax,%ebx
  shr    $0x1f,%ebx
  add    %eax,%ebx
  sar    %ebx
  cmp    %ebx,%r8d
  jge    L63
  lea    (%r8,%rbx,1),%eax
  mov    %r8d,%edi
  mov    %r8d,0x8(%rsp)
  mov    %eax,%r9d
  shr    $0x1f,%r9d
  add    %eax,%r9d
  sar    %r9d
  mov    %r9d,%esi
  mov    %r9d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r9d
  mov    %ebx,%esi
  lea    0x1(%r9),%edi
  call   <partition>
  mov    0x8(%rsp),%r8d
  mov    0x4(%rsp),%esi
  mov    %ebx,%edx
  mov    %r8d,%edi
  mov    %r8d,0x4(%rsp)
  call   <merge@plt>
  mov    0x4(%rsp),%r8d
L63:
  lea    0x1(%rbx),%r10d
  cmp    %r10d,%r12d
  jle    L11
  lea    (%r12,%r10,1),%eax
  mov    %r10d,%edi
  mov    %r8d,0xc(%rsp)
  mov    %eax,%r9d
  mov    %r10d,0x8(%rsp)
  shr    $0x1f,%r9d
  add    %eax,%r9d
  sar    %r9d
  mov    %r9d,%esi
  mov    %r9d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r9d
  mov    %r12d,%esi
  lea    0x1(%r9),%edi
  call   <partition>
  mov    0x4(%rsp),%esi
  mov    0x8(%rsp),%edi
  mov    %r12d,%edx
  call   <merge@plt>
  mov    0xc(%rsp),%r8d
L11:
  mov    %r12d,%edx
  mov    %ebx,%esi
  mov    %r8d,%edi
  call   <merge@plt>
  jmp    L147
  nopl   0x0(%rax)
L59:
  lea    (%r15,%r14,1),%eax
  mov    %eax,%ebx
  shr    $0x1f,%ebx
  add    %eax,%ebx
  sar    %ebx
  cmp    %ebx,%r15d
  jge    L155
  lea    (%r15,%rbx,1),%eax
  mov    %r15d,%edi
  mov    %eax,%r8d
  shr    $0x1f,%r8d
  add    %eax,%r8d
  sar    %r8d
  mov    %r8d,%esi
  mov    %r8d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r8d
  mov    %ebx,%esi
  lea    0x1(%r8),%edi
  call   <partition>
  mov    0x4(%rsp),%esi
  mov    %ebx,%edx
  mov    %r15d,%edi
  call   <merge@plt>
L155:
  lea    0x1(%rbx),%r9d
  cmp    %r9d,%r14d
  jle    L65
  lea    (%r14,%r9,1),%eax
  mov    %r9d,%edi
  mov    %r9d,0x8(%rsp)
  mov    %eax,%r8d
  shr    $0x1f,%r8d
  add    %eax,%r8d
  sar    %r8d
  mov    %r8d,%esi
  mov    %r8d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r8d
  mov    %r14d,%esi
  lea    0x1(%r8),%edi
  call   <partition>
  mov    0x4(%rsp),%esi
  mov    0x8(%rsp),%edi
  mov    %r14d,%edx
  call   <merge@plt>
L65:
  mov    %r14d,%edx
  mov    %ebx,%esi
  mov    %r15d,%edi
  call   <merge@plt>
  lea    0x1(%r14),%r8d
  cmp    %r8d,%r12d
  jle    L147
  jmp    L61
L96:
  lea    0x0(%r13,%rbx,1),%eax
  mov    %eax,%r15d
  shr    $0x1f,%r15d
  add    %eax,%r15d
  sar    %r15d
  cmp    %r15d,%ebx
  jge    L15
  lea    (%rbx,%r15,1),%eax
  mov    %ebx,%edi
  mov    %eax,%r8d
  shr    $0x1f,%r8d
  add    %eax,%r8d
  sar    %r8d
  mov    %r8d,%esi
  mov    %r8d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r8d
  mov    %r15d,%esi
  lea    0x1(%r8),%edi
  call   <partition>
  mov    0x4(%rsp),%esi
  mov    %r15d,%edx
  mov    %ebx,%edi
  call   <merge@plt>
L15:
  lea    0x1(%r15),%r9d
  cmp    %r9d,%r13d
  jle    L22
  lea    0x0(%r13,%r9,1),%eax
  mov    %r9d,%edi
  mov    %r9d,0x8(%rsp)
  mov    %eax,%r8d
  shr    $0x1f,%r8d
  add    %eax,%r8d
  sar    %r8d
  mov    %r8d,%esi
  mov    %r8d,0x4(%rsp)
  call   <partition>
  mov    0x4(%rsp),%r8d
  mov    %r13d,%esi
  lea    0x1(%r8),%edi
  call   <partition>
  mov    0x4(%rsp),%esi
  mov    0x8(%rsp),%edi
  mov    %r13d,%edx
  call   <merge@plt>
L22:
  mov    %r13d,%edx
  mov    %r15d,%esi
  mov    %ebx,%edi
  call   <merge@plt>
  jmp    L76
  nopl   0x0(%rax)
L101:
  lea    (%rdi,%r14,1),%eax
  mov    %eax,%r15d
  shr    $0x1f,%r15d
  add    %eax,%r15d
  sar    %r15d
  cmp    %r15d,%edi
  jge    L174
  lea    (%rdi,%r15,1),%eax
  mov    %eax,%ebx
  shr    $0x1f,%ebx
  add    %eax,%ebx
  sar    %ebx
  mov    %ebx,%esi
  call   <partition>
  lea    0x1(%rbx),%edi
  mov    %r15d,%esi
  call   <partition>
  mov    %r15d,%edx
  mov    %ebx,%esi
  mov    %ebp,%edi
  call   <merge@plt>
L174:
  lea    0x1(%r15),%r8d
  cmp    %r8d,%r14d
  jle    L83
  lea    (%r14,%r8,1),%eax
  mov    %r8d,%edi
  mov    %r8d,0x4(%rsp)
  mov    %eax,%ebx
  shr    $0x1f,%ebx
  add    %eax,%ebx
  sar    %ebx
  mov    %ebx,%esi
  call   <partition>
  lea    0x1(%rbx),%edi
  mov    %r14d,%esi
  call   <partition>
  mov    0x4(%rsp),%edi
  mov    %r14d,%edx
  mov    %ebx,%esi
  call   <merge@plt>
L83:
  mov    %r14d,%edx
  mov    %r15d,%esi
  lea    0x1(%r14),%ebx
  mov    %ebp,%edi
  call   <merge@plt>
  cmp    %ebx,%r13d
  jle    L76
  jmp    L96
```

assistant: ```c
void partition(int beg, int end) {
  int mid;
  if (beg < end) {
    mid = ((beg + end) / 2);
    partition(beg, mid);
    partition(mid + 1, end);
    merge(beg, mid, end);
  } else
    return;
}
```