user: 这段汇编代码用C语言表示是什么样的：

```asm
<dscal>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  mov    %edi,-0x14(%rbp)
  movsd  %xmm0,-0x20(%rbp)
  mov    %rsi,-0x28(%rbp)
  mov    %edx,-0x18(%rbp)
  movl   $0x0,-0xc(%rbp)
  movl   $0x0,-0x8(%rbp)
  cmpl   $0x0,-0x14(%rbp)
  jle    L30
  cmpl   $0x1,-0x18(%rbp)
  je     L70
  mov    -0x14(%rbp),%eax
  imul   -0x18(%rbp),%eax
  mov    %eax,-0x4(%rbp)
  movl   $0x0,-0x10(%rbp)
  jmp    L36
L96:
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  mov    -0x18(%rbp),%eax
  add    %eax,-0x10(%rbp)
L36:
  mov    -0x10(%rbp),%eax
  cmp    -0x4(%rbp),%eax
  jl     L96
  jmp    L59
L70:
  mov    -0x14(%rbp),%eax
  movslq %eax,%rdx
  imul   $0x66666667,%rdx,%rdx
  shr    $0x20,%rdx
  sar    %edx
  mov    %eax,%esi
  sar    $0x1f,%esi
  mov    %edx,%ecx
  sub    %esi,%ecx
  mov    %ecx,%edx
  shl    $0x2,%edx
  add    %ecx,%edx
  sub    %edx,%eax
  mov    %eax,-0x8(%rbp)
  cmpl   $0x0,-0x8(%rbp)
  je     L108
  movl   $0x0,-0x10(%rbp)
  jmp    L53
L103:
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  addl   $0x1,-0x10(%rbp)
L53:
  mov    -0x10(%rbp),%eax
  cmp    -0x8(%rbp),%eax
  jl     L103
  cmpl   $0x4,-0x14(%rbp)
  jle    L3
L108:
  mov    -0x8(%rbp),%eax
  mov    %eax,-0x10(%rbp)
  jmp    L107
L43:
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x2,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x2,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x4,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  movsd  (%rax),%xmm0
  mov    -0x10(%rbp),%eax
  cltq
  add    $0x4,%rax
  lea    0x0(,%rax,8),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mulsd  -0x20(%rbp),%xmm0
  movsd  %xmm0,(%rax)
  addl   $0x5,-0x10(%rbp)
L107:
  mov    -0x10(%rbp),%eax
  cmp    -0x14(%rbp),%eax
  jl     L43
  jmp    L59
L30:
  nop
  jmp    L59
L3:
  nop
L59:
  pop    %rbp
  ret
```

assistant: ```c
void dscal(int n, double da, double dx[], int incx) {
  int i, m, mp1, nincx;
  mp1 = 0;
  m = 0;
  if (n <= 0)
    return;
  if (incx != 1) {
    nincx = n * incx;
    for (i = 0; i < nincx; i = i + incx)
      dx[i] = da * dx[i];
    return;
  }
  m = n % 5;
  if (m != 0) {
    for (i = 0; i < m; i++)
      dx[i] = da * dx[i];
    if (n < 5)
      return;
  }
  for (i = m; i < n; i = i + 5) {
    dx[i] = da * dx[i];
    dx[i + 1] = da * dx[i + 1];
    dx[i + 2] = da * dx[i + 2];
    dx[i + 3] = da * dx[i + 3];
    dx[i + 4] = da * dx[i + 4];
  }
}
```