user: 请从给定的汇编指令推导出C源代码:

```asm
<atof>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x30,%rsp
  mov    %rdi,-0x28(%rbp)
  mov    -0x28(%rbp),%rax
  mov    %rax,-0x8(%rbp)
  movl   $0x0,-0x20(%rbp)
  jmp    L94
L26:
  addl   $0x1,-0x20(%rbp)
L94:
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isspace@plt>
  test   %rax,%rax
  jne    L26
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2d,%al
  jne    L80
  mov    $0xffffffff,%eax
  jmp    L45
L80:
  mov    $0x1,%eax
L45:
  mov    %eax,-0x1c(%rbp)
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2b,%al
  je     L33
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2d,%al
  jne    L85
L33:
  addl   $0x1,-0x20(%rbp)
L85:
  pxor   %xmm0,%xmm0
  movsd  %xmm0,-0x18(%rbp)
  jmp    L74
L12:
  movsd  -0x18(%rbp),%xmm1
  movsd  D35(%rip),%xmm0
  mulsd  %xmm0,%xmm1
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x30,%eax
  pxor   %xmm0,%xmm0
  cvtsi2sd %eax,%xmm0
  addsd  %xmm1,%xmm0
  movsd  %xmm0,-0x18(%rbp)
  addl   $0x1,-0x20(%rbp)
L74:
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isdigit@plt>
  test   %rax,%rax
  jne    L12
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  cmp    $0x2e,%al
  jne    L68
  addl   $0x1,-0x20(%rbp)
L68:
  movsd  D1(%rip),%xmm0
  movsd  %xmm0,-0x10(%rbp)
  jmp    L87
L3:
  movsd  -0x18(%rbp),%xmm1
  movsd  D35(%rip),%xmm0
  mulsd  %xmm0,%xmm1
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  sub    $0x30,%eax
  pxor   %xmm0,%xmm0
  cvtsi2sd %eax,%xmm0
  addsd  %xmm1,%xmm0
  movsd  %xmm0,-0x18(%rbp)
  movsd  -0x10(%rbp),%xmm1
  movsd  D35(%rip),%xmm0
  mulsd  %xmm1,%xmm0
  movsd  %xmm0,-0x10(%rbp)
  addl   $0x1,-0x20(%rbp)
L87:
  mov    -0x20(%rbp),%eax
  movslq %eax,%rdx
  mov    -0x8(%rbp),%rax
  add    %rdx,%rax
  movzbl (%rax),%eax
  movsbl %al,%eax
  mov    %eax,%edi
  call   <isdigit@plt>
  test   %rax,%rax
  jne    L3
  pxor   %xmm0,%xmm0
  cvtsi2sdl -0x1c(%rbp),%xmm0
  mulsd  -0x18(%rbp),%xmm0
  divsd  -0x10(%rbp),%xmm0
  movq   %xmm0,%rax
  movq   %rax,%xmm0
  leave
  ret
```

tool_calls: name: extract_symbolic_data
arguments: data_label: D35
type: f64
name: extract_symbolic_data
arguments: data_label: D1
type: f64

tool: D35: 10

tool: D1: 1

assistant: ```c
double atof(const char *nptr) {
  double val, power;
  int i, sign;
  const char *s = nptr;
  for (i = 0; isspace(s[i]); i++)
    ;
  sign = (s[i] == '-') ? -1 : 1;
  if (s[i] == '+' || s[i] == '-')
    i++;
  for (val = 0.0; isdigit(s[i]); i++)
    val = 10.0 * val + (s[i] - '0');
  if (s[i] == '.')
    i++;
  for (power = 1.0; isdigit(s[i]); i++) {
    val = 10.0 * val + (s[i] - '0');
    power *= 10;
  }
  return sign * val / power;
}
```