user: Converte this assembly snippet into its equivalent C code:

```asm
<internal_fiat_p448_add>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  mov    %rsi,%r12
  mov    $0x8,%esi
  push   %rbp
  mov    %rdx,%rbp
  push   %rbx
  mov    %rdi,%rbx
  mov    %r12d,%edi
  sub    $0x68,%rsp
  call   <_br2_load@plt>
  lea    0x8(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x8(%rsp)
  call   <_br2_load@plt>
  lea    0x10(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x10(%rsp)
  call   <_br2_load@plt>
  lea    0x18(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x18(%rsp)
  call   <_br2_load@plt>
  lea    0x20(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x20(%rsp)
  call   <_br2_load@plt>
  lea    0x28(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x28(%rsp)
  call   <_br2_load@plt>
  lea    0x30(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x30(%rsp)
  call   <_br2_load@plt>
  lea    0x38(%r12),%edi
  mov    $0x8,%esi
  mov    %rax,0x38(%rsp)
  call   <_br2_load@plt>
  mov    %ebp,%edi
  mov    $0x8,%esi
  mov    %rax,%r12
  call   <_br2_load@plt>
  lea    0x8(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,0x40(%rsp)
  call   <_br2_load@plt>
  lea    0x10(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,0x48(%rsp)
  call   <_br2_load@plt>
  lea    0x18(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,%r15
  call   <_br2_load@plt>
  lea    0x20(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,0x50(%rsp)
  call   <_br2_load@plt>
  lea    0x28(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,%r14
  call   <_br2_load@plt>
  lea    0x30(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,%r13
  call   <_br2_load@plt>
  lea    0x38(%rbp),%edi
  mov    $0x8,%esi
  mov    %rax,0x58(%rsp)
  call   <_br2_load@plt>
  mov    0x10(%rsp),%r8
  mov    0x38(%rsp),%r9
  mov    %ebx,%edi
  add    0x48(%rsp),%r8
  add    0x58(%rsp),%r9
  mov    $0x8,%edx
  add    %rax,%r12
  mov    0x8(%rsp),%rsi
  add    0x40(%rsp),%rsi
  mov    %r8,0x48(%rsp)
  add    0x18(%rsp),%r15
  add    0x28(%rsp),%r14
  mov    %r9,0x10(%rsp)
  add    0x30(%rsp),%r13
  mov    0x20(%rsp),%rbp
  add    0x50(%rsp),%rbp
  call   <_br2_store@plt>
  mov    0x48(%rsp),%rsi
  lea    0x8(%rbx),%edi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  lea    0x10(%rbx),%edi
  mov    %r15,%rsi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  lea    0x18(%rbx),%edi
  mov    %rbp,%rsi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  lea    0x20(%rbx),%edi
  mov    %r14,%rsi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  lea    0x28(%rbx),%edi
  mov    %r13,%rsi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  mov    0x10(%rsp),%rsi
  lea    0x30(%rbx),%edi
  mov    $0x8,%edx
  call   <_br2_store@plt>
  add    $0x68,%rsp
  lea    0x38(%rbx),%edi
  mov    %r12,%rsi
  pop    %rbx
  mov    $0x8,%edx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  jmp    1060 <_br2_store@plt>
```

assistant: ```c
void internal_fiat_p448_add(uintptr_t out0, uintptr_t in0, uintptr_t in1) {
  uintptr_t x0, x8, x1, x9, x2, x10, x3, x11, x4, x12, x5, x13, x6, x14, x7, x15, x16, x17, x18, x19, x20, x21, x22, x23, x24, x25, x26, x27, x28, x29, x30, x31;
  x0 = _br2_load((in0) + ((uintptr_t)0ULL), sizeof(uintptr_t));
  x1 = _br2_load((in0) + ((uintptr_t)8ULL), sizeof(uintptr_t));
  x2 = _br2_load((in0) + ((uintptr_t)16ULL), sizeof(uintptr_t));
  x3 = _br2_load((in0) + ((uintptr_t)24ULL), sizeof(uintptr_t));
  x4 = _br2_load((in0) + ((uintptr_t)32ULL), sizeof(uintptr_t));
  x5 = _br2_load((in0) + ((uintptr_t)40ULL), sizeof(uintptr_t));
  x6 = _br2_load((in0) + ((uintptr_t)48ULL), sizeof(uintptr_t));
  x7 = _br2_load((in0) + ((uintptr_t)56ULL), sizeof(uintptr_t));
  x8 = _br2_load((in1) + ((uintptr_t)0ULL), sizeof(uintptr_t));
  x9 = _br2_load((in1) + ((uintptr_t)8ULL), sizeof(uintptr_t));
  x10 = _br2_load((in1) + ((uintptr_t)16ULL), sizeof(uintptr_t));
  x11 = _br2_load((in1) + ((uintptr_t)24ULL), sizeof(uintptr_t));
  x12 = _br2_load((in1) + ((uintptr_t)32ULL), sizeof(uintptr_t));
  x13 = _br2_load((in1) + ((uintptr_t)40ULL), sizeof(uintptr_t));
  x14 = _br2_load((in1) + ((uintptr_t)48ULL), sizeof(uintptr_t));
  x15 = _br2_load((in1) + ((uintptr_t)56ULL), sizeof(uintptr_t));
  x16 = (x0) + (x8);
  x17 = (x1) + (x9);
  x18 = (x2) + (x10);
  x19 = (x3) + (x11);
  x20 = (x4) + (x12);
  x21 = (x5) + (x13);
  x22 = (x6) + (x14);
  x23 = (x7) + (x15);
  x24 = x16;
  x25 = x17;
  x26 = x18;
  x27 = x19;
  x28 = x20;
  x29 = x21;
  x30 = x22;
  x31 = x23;
  _br2_store((out0) + ((uintptr_t)0ULL), x24, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)8ULL), x25, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)16ULL), x26, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)24ULL), x27, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)32ULL), x28, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)40ULL), x29, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)48ULL), x30, sizeof(uintptr_t));
  _br2_store((out0) + ((uintptr_t)56ULL), x31, sizeof(uintptr_t));
  return;
}
```