user: 请将这段汇编代码片段转换成等效的C代码：

```asm
<c_nb_step>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x70,%rsp
  mov    %rdi,-0x58(%rbp)
  mov    %rsi,-0x60(%rbp)
  movss  %xmm0,-0x64(%rbp)
  mov    %edx,-0x68(%rbp)
  mov    -0x58(%rbp),%rax
  mov    %rax,-0x38(%rbp)
  mov    -0x60(%rbp),%rax
  mov    %rax,-0x30(%rbp)
  movl   $0x0,-0x50(%rbp)
  jmp    L19
L26:
  pxor   %xmm0,%xmm0
  movsd  %xmm0,-0x48(%rbp)
  pxor   %xmm0,%xmm0
  movsd  %xmm0,-0x40(%rbp)
  movl   $0x0,-0x4c(%rbp)
  jmp    L18
L29:
  mov    -0x50(%rbp),%eax
  cmp    -0x4c(%rbp),%eax
  je     L56
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  mov    -0x4c(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm1
  subss  %xmm1,%xmm0
  cvtss2sd %xmm0,%xmm0
  movsd  %xmm0,-0x28(%rbp)
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  mov    -0x4c(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm1
  subss  %xmm1,%xmm0
  cvtss2sd %xmm0,%xmm0
  movsd  %xmm0,-0x20(%rbp)
  movsd  -0x28(%rbp),%xmm0
  movapd %xmm0,%xmm1
  mulsd  %xmm0,%xmm1
  movsd  -0x20(%rbp),%xmm0
  mulsd  %xmm0,%xmm0
  addsd  %xmm1,%xmm0
  movsd  %xmm0,-0x18(%rbp)
  mov    -0x18(%rbp),%rax
  movq   %rax,%xmm0
  call   <sqrt@plt>
  movq   %xmm0,%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm1
  mov    -0x4c(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  mulss  %xmm1,%xmm0
  cvtss2sd %xmm0,%xmm0
  movapd %xmm0,%xmm1
  divsd  -0x18(%rbp),%xmm1
  movsd  D2(%rip),%xmm0
  mulsd  %xmm1,%xmm0
  movsd  %xmm0,-0x8(%rbp)
  movsd  -0x28(%rbp),%xmm0
  divsd  -0x10(%rbp),%xmm0
  movapd %xmm0,%xmm1
  mulsd  -0x8(%rbp),%xmm1
  movsd  -0x48(%rbp),%xmm0
  subsd  %xmm1,%xmm0
  movsd  %xmm0,-0x48(%rbp)
  movsd  -0x20(%rbp),%xmm0
  divsd  -0x10(%rbp),%xmm0
  movapd %xmm0,%xmm1
  mulsd  -0x8(%rbp),%xmm1
  movsd  -0x40(%rbp),%xmm0
  subsd  %xmm1,%xmm0
  movsd  %xmm0,-0x40(%rbp)
  jmp    L37
L56:
  nop
L37:
  addl   $0x1,-0x4c(%rbp)
L18:
  mov    -0x4c(%rbp),%eax
  cmp    -0x68(%rbp),%eax
  jl     L29
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  pxor   %xmm1,%xmm1
  cvtss2sd %xmm0,%xmm1
  pxor   %xmm2,%xmm2
  cvtss2sd -0x64(%rbp),%xmm2
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  pxor   %xmm3,%xmm3
  cvtss2sd %xmm0,%xmm3
  movsd  -0x48(%rbp),%xmm0
  divsd  %xmm3,%xmm0
  mulsd  %xmm2,%xmm0
  addsd  %xmm1,%xmm0
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  cvtsd2ss %xmm0,%xmm0
  movss  %xmm0,(%rax)
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  pxor   %xmm1,%xmm1
  cvtss2sd %xmm0,%xmm1
  pxor   %xmm2,%xmm2
  cvtss2sd -0x64(%rbp),%xmm2
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  pxor   %xmm3,%xmm3
  cvtss2sd %xmm0,%xmm3
  movsd  -0x40(%rbp),%xmm0
  divsd  %xmm3,%xmm0
  mulsd  %xmm2,%xmm0
  addsd  %xmm1,%xmm0
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  cvtsd2ss %xmm0,%xmm0
  movss  %xmm0,(%rax)
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm1
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  mulss  -0x64(%rbp),%xmm0
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  addss  %xmm1,%xmm0
  movss  %xmm0,(%rax)
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm1
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  movss  (%rax),%xmm0
  mulss  -0x64(%rbp),%xmm0
  mov    -0x50(%rbp),%eax
  shl    $0x2,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  addss  %xmm1,%xmm0
  movss  %xmm0,(%rax)
  addl   $0x1,-0x50(%rbp)
L19:
  mov    -0x50(%rbp),%eax
  cmp    -0x68(%rbp),%eax
  jl     L26
  nop
  nop
  leave
  ret
```

tool_calls: name: extract_symbolic_data
arguments: tag: D2
data_type: byte[8]

tool: {"D2": [0xd1,0x37,0x97,0x65,0x9b,0x58,0xd2,0x3d]}

assistant: ```c
void c_nb_step(unsigned long ipos, unsigned long ivel, float dt, int n_bodies) {
  float *pos = (float *)ipos;
  float *vel = (float *)ivel;
  int i;
  int j;
  for (i = 0; i < n_bodies; i++) {
    double f_x = 0.0;
    double f_y = 0.0;
    for (j = 0; j < n_bodies; j++) {
      double d_x;
      double d_y;
      double dist_tmp;
      double distance;
      double force;
      if (i == j) {
        continue;
      }
      d_x = pos[i * 4] - pos[j * 4];
      d_y = pos[i * 4 + 1] - pos[j * 4 + 1];
      dist_tmp = (d_x * d_x) + (d_y * d_y);
      distance = sqrt(dist_tmp);
      force = 6.67428e-11 * ((pos[i * 4 + 3] * pos[j * 4 + 3]) / dist_tmp);
      f_x -= force * (d_x / distance);
      f_y -= force * (d_y / distance);
    }
    vel[i * 4] += dt * (f_x / pos[i * 4 + 3]);
    vel[i * 4 + 1] += dt * (f_y / pos[i * 4 + 3]);
    pos[i * 4] += dt * vel[i * 4];
    pos[i * 4 + 1] += dt * vel[i * 4 + 1];
  }
}
```