user: Demonstrate the C code that generates the assembly output below:

```asm
<MD4_Update>:
  endbr64
  test   %rdx,%rdx
  je     L640
  push   %r14
  push   %r13
  mov    D3(%rip),%r13
  push   %r12
  mov    %rdi,%r12
  push   %rbp
  mov    %rsi,%rbp
  mov    %edx,%esi
  push   %rbx
  mov    (%rdi),%eax
  mov    %rdx,%rbx
  mov    0x0(%r13),%r9
  lea    (%rax,%rdx,8),%ecx
  xor    %edx,%edx
  cmp    %ecx,%eax
  mov    %rbx,%rax
  mov    %ecx,(%rdi)
  setg   %dl
  shr    $0x1d,%rax
  add    0x10(%rdi),%rdx
  add    %rdx,%rax
  mov    %rax,0x10(%rdi)
  mov    0x4(%rdi),%eax
  test   %eax,%eax
  jne    L616
  cmp    %r9,%rbx
  jae    L449
L622:
  mov    %esi,0x4(%r12)
  mov    %rbx,%rdi
  mov    %rbx,%rsi
  mov    0x8(%r12),%rdx
  and    $0x3,%edi
  shr    $0x2,%rsi
  je     L20
  lea    0x4(%rbp),%rcx
  mov    %rdx,%rax
  lea    -0x1(%rsi),%r8
  sub    %rcx,%rax
  cmp    $0x8,%rax
  jbe    L554
  cmp    $0x2,%r8
  jbe    L554
  mov    %rbx,%rcx
  xor    %eax,%eax
  and    $0xfffffffffffffff0,%rbx
  shr    $0x4,%rcx
  nopl   0x0(%rax,%rax,1)
L585:
  movdqu 0x0(%rbp,%rax,1),%xmm0
  movups %xmm0,(%rdx,%rax,1)
  add    $0x10,%rax
  cmp    %rax,%rbx
  jne    L585
  mov    %rcx,%rax
  lea    0x0(,%rcx,4),%r9
  shl    $0x4,%rax
  lea    0x0(%rbp,%rax,1),%rcx
  add    %rdx,%rax
  cmp    %r9,%rsi
  je     L427
  mov    (%rcx),%r10d
  mov    %r10d,(%rax)
  sub    %r9,%r8
  je     L427
  mov    0x4(%rcx),%r9d
  mov    %r9d,0x4(%rax)
  cmp    $0x1,%r8
  je     L427
  mov    0x8(%rcx),%ecx
  mov    %ecx,0x8(%rax)
L427:
  shl    $0x2,%rsi
  add    %rsi,%rbp
  add    %rsi,%rdx
L20:
  lea    0x0(%rbp,%rdi,1),%rax
  cmp    $0x2,%rdi
  je     L24
  cmp    $0x3,%rdi
  je     L530
  cmp    $0x1,%rdi
  je     L12
  xor    %eax,%eax
L545:
  mov    %eax,(%rdx)
L529:
  pop    %rbx
  mov    $0x1,%eax
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  ret
  nopl   (%rax)
L616:
  mov    %eax,%ecx
  mov    0x8(%rdi),%rsi
  movslq %eax,%rdx
  mov    %eax,%r10d
  sar    $0x2,%ecx
  add    %rbx,%rdx
  and    $0x3,%r10d
  movslq %ecx,%rcx
  lea    0x0(,%rcx,4),%r8
  lea    (%rsi,%r8,1),%rdi
  cmp    %r9,%rdx
  jb     L244
  mov    (%rdi),%eax
  movzbl 0x0(%rbp),%edx
  cmp    $0x2,%r10d
  je     L236
  cmp    $0x3,%r10d
  je     L55
  cmp    $0x1,%r10d
  je     L65
  add    $0x1,%rbp
  movzbl %dl,%eax
L65:
  movzbl 0x0(%rbp),%r9d
  lea    0x1(%rbp),%rdx
  shl    $0x8,%r9
  or     %r9d,%eax
L271:
  lea    0x1(%rdx),%rbp
  movzbl (%rdx),%edx
  shl    $0x10,%rdx
  or     %edx,%eax
L55:
  movzbl 0x0(%rbp),%r10d
  lea    0x1(%rcx),%rdx
  lea    0x1(%rbp),%r9
  shl    $0x18,%r10
  or     %r10d,%eax
  mov    %eax,(%rdi)
  mov    D19(%rip),%rax
  mov    (%rax),%r10
  cmp    %r10,%rdx
  jae    L313
  mov    %r10,%r11
  lea    0x4(%rsi,%r8,1),%rdi
  sub    %rcx,%r11
  mov    %rdi,%rax
  lea    0x5(%rbp),%rcx
  sub    %rcx,%rax
  cmp    $0x8,%rax
  jbe    L18
  lea    -0x2(%r11),%rax
  cmp    $0x2,%rax
  jbe    L18
  lea    -0x1(%r11),%r8
  xor    %eax,%eax
  mov    %r8,%rcx
  shr    $0x2,%rcx
  shl    $0x4,%rcx
  nopl   (%rax)
L227:
  movdqu 0x1(%rbp,%rax,1),%xmm1
  movups %xmm1,(%rdi,%rax,1)
  add    $0x10,%rax
  cmp    %rax,%rcx
  jne    L227
  mov    %r8,%rax
  and    $0xfffffffffffffffc,%rax
  lea    (%r9,%rax,4),%rcx
  add    %rax,%rdx
  cmp    %r8,%rax
  je     L97
  mov    (%rcx),%edi
  lea    0x0(,%rdx,4),%rax
  mov    %edi,(%rsi,%rdx,4)
  lea    0x1(%rdx),%rdi
  cmp    %rdi,%r10
  jbe    L97
  mov    0x4(%rcx),%edi
  add    $0x2,%rdx
  mov    %edi,0x4(%rsi,%rax,1)
  cmp    %r10,%rdx
  jae    L97
  mov    0x8(%rcx),%edx
  mov    %edx,0x8(%rsi,%rax,1)
L97:
  lea    (%r9,%r8,4),%rbp
L463:
  mov    $0x1,%edx
  mov    %r12,%rdi
  call   <md4_block_host_order@plt>
  movslq 0x4(%r12),%rax
  mov    0x0(%r13),%rcx
  movl   $0x0,0x4(%r12)
  add    %rbx,%rax
  sub    %rcx,%rax
  mov    %rax,%rbx
  cmp    %rax,%rcx
  jbe    L105
L30:
  test   %rbx,%rbx
  je     L529
  mov    %ebx,%esi
  jmp    L622
L640:
  mov    $0x1,%eax
  ret
  cs nopw 0x0(%rax,%rax,1)
L12:
  xor    %ecx,%ecx
L340:
  movzbl -0x1(%rax),%eax
  or     %ecx,%eax
  jmp    L545
  nopl   (%rax)
L530:
  movzbl -0x1(%rax),%ecx
  add    $0x2,%rbp
  shl    $0x10,%ecx
L23:
  movzbl -0x1(%rbp),%esi
  lea    -0x1(%rbp),%rax
  shl    $0x8,%rsi
  or     %esi,%ecx
  jmp    L340
  nopl   0x0(%rax,%rax,1)
L236:
  mov    %rbp,%rdx
  jmp    L271
  nopl   0x0(%rax,%rax,1)
L244:
  movslq %r10d,%rdx
  add    %ebx,%eax
  add    %rbx,%rdx
  mov    %eax,0x4(%r12)
  cmp    $0x3,%rdx
  ja     L354
  mov    (%rdi),%eax
  cmp    $0x1,%r10d
  je     L281
  cmp    $0x2,%r10d
  je     L455
  test   %r10d,%r10d
  je     L565
L282:
  mov    %eax,(%rdi)
  jmp    L529
  nopl   0x0(%rax)
L449:
  mov    %rbx,%rax
  xor    %edx,%edx
  div    %r9
  mov    %rax,%r14
L501:
  mov    %rbp,%rsi
  mov    %r14,%rdx
  mov    %r12,%rdi
  call   <md4_block_data_order@plt>
  mov    0x0(%r13),%rax
  imul   %r14,%rax
  add    %rax,%rbp
  sub    %rax,%rbx
  jmp    L30
  nopl   0x0(%rax)
L105:
  xor    %edx,%edx
  div    %rcx
  mov    %rax,%r14
  jmp    L501
  nopw   0x0(%rax,%rax,1)
L24:
  mov    %rax,%rbp
  xor    %ecx,%ecx
  jmp    L23
  nopw   0x0(%rax,%rax,1)
L354:
  mov    %eax,%r11d
  and    $0x3,%eax
  sar    $0x2,%r11d
  movslq %r11d,%r11
  test   %r10d,%r10d
  je     L291
  mov    (%rdi),%edx
  cmp    $0x2,%r10d
  je     L476
  cmp    $0x3,%r10d
  je     L381
  cmp    $0x1,%r10d
  je     L374
L291:
  movzbl 0x0(%rbp),%edx
  add    $0x1,%rbp
L374:
  movzbl 0x0(%rbp),%r10d
  lea    0x1(%rbp),%r9
  shl    $0x8,%r10
  or     %r10d,%edx
L174:
  lea    0x1(%r9),%rbp
  movzbl (%r9),%r9d
  shl    $0x10,%r9
  or     %r9d,%edx
L381:
  movzbl 0x0(%rbp),%ebx
  lea    0x1(%rcx),%r9
  lea    0x1(%rbp),%r10
  shl    $0x18,%rbx
  or     %ebx,%edx
  mov    %edx,(%rdi)
  cmp    %r9,%r11
  jbe    L320
  mov    %r11,%rdi
  lea    0x4(%rsi,%r8,1),%rbx
  sub    %rcx,%rdi
  mov    %rbx,%rdx
  lea    0x5(%rbp),%rcx
  sub    %rcx,%rdx
  cmp    $0x8,%rdx
  jbe    L517
  lea    -0x2(%rdi),%rdx
  cmp    $0x2,%rdx
  jbe    L517
  lea    -0x1(%rdi),%rcx
  xor    %edx,%edx
  mov    %rcx,%rdi
  shr    $0x2,%rdi
  shl    $0x4,%rdi
  nopl   0x0(%rax)
L438:
  movdqu 0x1(%rbp,%rdx,1),%xmm2
  movups %xmm2,(%rbx,%rdx,1)
  add    $0x10,%rdx
  cmp    %rdx,%rdi
  jne    L438
  mov    %rcx,%rdx
  and    $0xfffffffffffffffc,%rdx
  lea    (%r10,%rdx,4),%rdi
  add    %rdx,%r9
  cmp    %rcx,%rdx
  je     L164
  mov    (%rdi),%r8d
  lea    0x0(,%r9,4),%rdx
  mov    %r8d,(%rsi,%r9,4)
  lea    0x1(%r9),%r8
  cmp    %r11,%r8
  jae    L164
  mov    0x4(%rdi),%r8d
  add    $0x2,%r9
  mov    %r8d,0x4(%rsi,%rdx,1)
  cmp    %r9,%r11
  jbe    L164
  mov    0x8(%rdi),%edi
  mov    %edi,0x8(%rsi,%rdx,1)
L164:
  lea    (%r10,%rcx,4),%r10
L509:
  test   %eax,%eax
  je     L529
  movslq %eax,%rdx
  add    %rdx,%r10
  xor    %edx,%edx
  movzbl -0x1(%r10),%ecx
  cmp    $0x2,%eax
  je     L431
  cmp    $0x3,%eax
  jne    L552
  movzbl %cl,%edx
  sub    $0x1,%r10
  shl    $0x10,%edx
L431:
  movzbl -0x1(%r10),%eax
  sub    $0x1,%r10
  shl    $0x8,%rax
  or     %eax,%edx
L552:
  movzbl -0x1(%r10),%eax
  or     %edx,%eax
  mov    %eax,(%rsi,%r11,4)
  jmp    L529
  nopl   0x0(%rax,%rax,1)
L554:
  lea    0x0(,%rsi,4),%r8
  xor    %eax,%eax
  nopw   0x0(%rax,%rax,1)
L193:
  mov    0x0(%rbp,%rax,1),%ecx
  mov    %ecx,(%rdx,%rax,1)
  add    $0x4,%rax
  cmp    %rax,%r8
  jne    L193
  jmp    L427
L313:
  mov    %r9,%rbp
  jmp    L463
L565:
  movzbl 0x0(%rbp),%eax
  sub    $0x1,%rbx
  je     L282
  add    $0x1,%rbp
L281:
  movzbl 0x0(%rbp),%edx
  shl    $0x8,%rdx
  or     %edx,%eax
  cmp    $0x1,%rbx
  je     L282
  add    $0x1,%rbp
L455:
  movzbl 0x0(%rbp),%edx
  shl    $0x10,%rdx
  or     %edx,%eax
  mov    %eax,(%rdi)
  jmp    L529
L18:
  sub    %r8,%rbp
  nopl   0x0(%rax,%rax,1)
L184:
  mov    -0x3(%rbp,%rdx,4),%eax
  mov    %eax,(%rsi,%rdx,4)
  add    $0x1,%rdx
  cmp    %rdx,%r10
  jne    L184
  lea    -0x1(%r11),%r8
  jmp    L97
L476:
  mov    %rbp,%r9
  jmp    L174
L517:
  sub    %r8,%rbp
  nopl   0x0(%rax)
L386:
  mov    -0x3(%rbp,%r9,4),%edx
  mov    %edx,(%rsi,%r9,4)
  add    $0x1,%r9
  cmp    %r9,%r11
  jne    L386
  lea    -0x1(%rdi),%rcx
  jmp    L164
L320:
  mov    %r9,%r11
  jmp    L509
```

assistant: ```c
int MD4_Update(MD4_CTX *c, const void *data_, size_t len) {
  const unsigned char *data = data_;
  register MD4_LONG *p;
  register MD4_LONG l;
  size_t sw, sc, ew, ec;
  if (len == 0)
    return 1;
  l = (c->Nl + (((MD4_LONG)len) << 3)) & 0xffffffffUL;
  if (l < c->Nl)
    c->Nh++;
  c->Nh += (len >> 29);
  c->Nl = l;
  if (c->num != 0) {
    p = c->data;
    sw = c->num >> 2;
    sc = c->num & 0x03;
    if ((c->num + len) >= MD4_CBLOCK) {
      l = p[sw];
      {
        switch (sc) {
        case 0:
          l = ((unsigned long)(*((data)++)));
        case 1:
          l |= ((unsigned long)(*((data)++))) << 8;
        case 2:
          l |= ((unsigned long)(*((data)++))) << 16;
        case 3:
          l |= ((unsigned long)(*((data)++))) << 24;
        }
      };
      p[sw++] = l;
      for (; sw < MD4_LBLOCK; sw++) {
        ((l) = *((const unsigned int *)(data)), (data) += 4, l);
        p[sw] = l;
      }
      md4_block_host_order(c, p, 1);
      len -= (MD4_CBLOCK - c->num);
      c->num = 0;
    } else {
      c->num += (unsigned int)len;
      if ((sc + len) < 4) {
        l = p[sw];
        {
          switch (sc) {
          case 0:
            l = ((unsigned long)(*((data)++)));
            if (--len == 0)
              break;
          case 1:
            l |= ((unsigned long)(*((data)++))) << 8;
            if (--len == 0)
              break;
          case 2:
            l |= ((unsigned long)(*((data)++))) << 16;
          }
        };
        p[sw] = l;
      } else {
        ew = (c->num >> 2);
        ec = (c->num & 0x03);
        if (sc)
          l = p[sw];
        {
          switch (sc) {
          case 0:
            l = ((unsigned long)(*((data)++)));
          case 1:
            l |= ((unsigned long)(*((data)++))) << 8;
          case 2:
            l |= ((unsigned long)(*((data)++))) << 16;
          case 3:
            l |= ((unsigned long)(*((data)++))) << 24;
          }
        };
        p[sw++] = l;
        for (; sw < ew; sw++) {
          ((l) = *((const unsigned int *)(data)), (data) += 4, l);
          p[sw] = l;
        }
        if (ec) {
          {
            l = 0;
            (data) += ec;
            switch (ec) {
            case 3:
              l = ((unsigned long)(*(--(data)))) << 16;
            case 2:
              l |= ((unsigned long)(*(--(data)))) << 8;
            case 1:
              l |= ((unsigned long)(*(--(data))));
            }
          };
          p[sw] = l;
        }
      }
      return 1;
    }
  }
  sw = len / MD4_CBLOCK;
  if (sw > 0) {
    {
      md4_block_data_order(c, data, sw);
      sw *= MD4_CBLOCK;
      data += sw;
      len -= sw;
    }
  }
  if (len != 0) {
    p = c->data;
    c->num = len;
    ew = len >> 2;
    ec = len & 0x03;
    for (; ew; ew--, p++) {
      ((l) = *((const unsigned int *)(data)), (data) += 4, l);
      *p = l;
    }
    {
      l = 0;
      (data) += ec;
      switch (ec) {
      case 3:
        l = ((unsigned long)(*(--(data)))) << 16;
      case 2:
        l |= ((unsigned long)(*(--(data)))) << 8;
      case 1:
        l |= ((unsigned long)(*(--(data))));
      }
    };
    *p = l;
  }
  return 1;
}
```