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

```asm
<uudecode>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x38,%rsp
  mov    %rdi,%r15
  mov    %rsi,0x10(%rsp)
  mov    %rdx,%r12
  mov    %rcx,%rbp
  mov    %fs:0x28,%rax
  mov    %rax,0x28(%rsp)
  xor    %eax,%eax
  test   %rcx,%rcx
  jne    L218
  mov    %rdx,%rdi
  call   <strlen@plt>
  mov    %rax,%rbp
L218:
  mov    $0x0,%r13d
  mov    $0x0,%ebx
  lea    0x24(%rsp),%rdi
  mov    %rdi,0x8(%rsp)
  mov    $0x1,%eax
  sub    %edi,%eax
  mov    %eax,0x4(%rsp)
  jmp    L46
L160:
  sub    $0x20,%edx
  mov    %dl,(%rax)
L40:
  mov    0x4(%rsp),%esi
  lea    (%rsi,%rax,1),%edx
  cmp    $0x3,%edx
  setbe  %cl
  cmp    %rbp,%rbx
  setb   %dl
  add    $0x1,%rax
  test   %dl,%cl
  je     L6
L14:
  add    $0x1,%rbx
  movzbl -0x1(%r12,%rbx,1),%edx
  cmp    $0x1f,%dl
  ja     L160
  mov    %dl,(%rax)
  jmp    L40
L6:
  movzbl 0x25(%rsp),%ecx
  movzbl 0x24(%rsp),%edx
  shl    $0x2,%edx
  mov    %ecx,%eax
  sar    $0x4,%eax
  and    $0x3,%eax
  or     %edx,%eax
  mov    %al,(%r15,%r13,1)
  movzbl 0x26(%rsp),%edx
  mov    %edx,%eax
  sar    $0x2,%eax
  and    $0xf,%eax
  shl    $0x4,%ecx
  or     %ecx,%eax
  mov    %al,0x1(%r15,%r13,1)
  add    $0x3,%r13
  movzbl 0x27(%rsp),%eax
  and    $0x3f,%eax
  shl    $0x6,%edx
  or     %edx,%eax
  mov    %al,-0x1(%r15,%r13,1)
  add    $0x3,%r14
  cmp    %r14,0x18(%rsp)
  seta   %dl
  cmp    %r13,0x10(%rsp)
  seta   %al
  test   %al,%dl
  je     L183
  cmp    %rbx,%rbp
  jbe    L183
L212:
  mov    $0x4,%edx
  mov    $0x0,%esi
  mov    0x8(%rsp),%rdi
  call   <memset@plt>
  cmp    %rbx,%rbp
  jbe    L6
  mov    0x8(%rsp),%rax
  jmp    L14
L183:
  cmp    %rbx,%rbp
  jbe    L46
L93:
  cmpb   $0x20,(%r12,%rbx,1)
  jle    L95
  add    $0x1,%rbx
  cmp    %rbp,%rbx
  jb     L93
L46:
  cmp    %rbp,%rbx
  jae    L155
  cmp    0x10(%rsp),%r13
  jae    L155
  add    $0x1,%rbx
  movzbl -0x1(%r12,%rbx,1),%eax
  cmp    $0x1f,%al
  jle    L46
  lea    0x20(%rax),%eax
  and    $0x3f,%eax
  mov    %rax,0x18(%rsp)
  je     L155
  cmp    %rbp,%rbx
  jae    L155
  mov    $0x0,%r14d
  jmp    L212
L95:
  cmp    %rbx,%rbp
  jbe    L46
L140:
  movzbl (%r12,%rbx,1),%eax
  cmp    $0x20,%al
  jg     L46
  test   %al,%al
  je     L46
  add    $0x1,%rbx
  cmp    %rbp,%rbx
  jne    L140
  mov    %rbp,%rbx
  jmp    L46
L155:
  mov    %r13d,%eax
  mov    0x28(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L180
  add    $0x38,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L180:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int uudecode(char *target, size_t tlen, const char *source, size_t slen) {
  int i;
  char ch;
  size_t rd = 0;
  size_t wr = 0;
  size_t block;
  size_t len;
  unsigned char cell[4];
  if (slen == 0)
    slen = strlen(source);
  while (rd < slen && wr < tlen) {
    ch = source[rd++];
    if (ch < ' ')
      continue;
    len = (ch - ' ') & 0x3f;
    if (len <= 0 || rd >= slen)
      break;
    block = 0;
    while (block < len && wr < tlen && rd < slen) {
      memset(cell, 0, sizeof(cell));
      for (i = 0; i < sizeof(cell) && rd < slen; i++) {
        cell[i] = source[rd++];
        if (cell[i] >= ' ')
          cell[i] -= ' ';
      }
      target[wr] = (cell[0] & 0x3f) << 2;
      target[wr++] |= (cell[1] & 0x30) >> 4;
      target[wr] = (cell[1] & 0x0f) << 4;
      target[wr++] |= (cell[2] & 0x3c) >> 2;
      target[wr] = (cell[2] & 0x03) << 6;
      target[wr++] |= cell[3] & 0x3f;
      block += 3;
    }
    while (rd < slen && source[rd] > ' ')
      rd++;
    while (rd < slen && source[rd] != 0 && source[rd] <= ' ')
      rd++;
  }
  return (wr);
}
```