user: 这段汇编代码用C语言表示是什么样的？

```asm
<crosscheck>:
  endbr64
  push   %r15
  mov    %ecx,%r15d
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  mov    %rdx,%rbp
  push   %rbx
  sub    $0x48,%rsp
  mov    %r9d,0x8(%rsp)
  mov    0x88(%rsp),%rbx
  mov    %rdi,0x20(%rsp)
  mov    0x80(%rsp),%r9
  mov    %rsi,0x28(%rsp)
  test   %r8d,%r8d
  jle    L94
  mov    %rdx,0x10(%rsp)
  xor    %r14d,%r14d
  movslq %r8d,%r12
  mov    %r8d,0x18(%rsp)
  mov    %r14,%rbp
  lea    0x0(,%r12,8),%r13
  mov    %r9,%r14
  nopw   0x0(%rax,%rax,1)
L71:
  movq   $0x0,(%rbx,%rbp,8)
  mov    (%r14,%rbp,8),%rdi
  mov    %r13,%rdx
  xor    %esi,%esi
  add    $0x1,%rbp
  call   <memset@plt>
  cmp    %r12,%rbp
  jne    L71
  mov    0x10(%rsp),%rbp
  mov    0x18(%rsp),%r8d
  mov    %r14,%r9
L94:
  test   %r15d,%r15d
  jle    L10
  movslq 0x8(%rsp),%r14
  lea    -0x1(%r8),%r13d
  lea    0x0(,%r14,4),%rax
  mov    %rax,0x8(%rsp)
  lea    0x0(,%r14,8),%rax
  xor    %r14d,%r14d
  mov    %rax,0x30(%rsp)
  movslq %r15d,%rax
  mov    %rax,0x10(%rsp)
  mov    %r8d,%eax
  shr    %eax
  lea    -0x1(%rax),%edi
  mov    %r8d,%eax
  and    $0xfffffffe,%eax
  add    $0x1,%rdi
  movslq %eax,%r10
  mov    %eax,0x3c(%rsp)
  shl    $0x4,%rdi
  shl    $0x3,%r10
  jmp    L85
  cs nopw 0x0(%rax,%rax,1)
L28:
  add    $0x1,%r14
  cmp    0x10(%rsp),%r14
  je     L10
L85:
  mov    0x0(%rbp,%r14,8),%rax
  mov    0x8(%rsp),%rsi
  mov    (%rax,%rsi,1),%eax
  test   %eax,%eax
  je     L28
  mov    0x20(%rsp),%rax
  mov    0x30(%rsp),%rsi
  mov    (%rax,%r14,8),%rcx
  mov    0x28(%rsp),%rax
  mov    (%rax,%r14,8),%rax
  movsd  (%rax,%rsi,1),%xmm3
  test   %r8d,%r8d
  jle    L28
  mov    %rbp,0x18(%rsp)
  mov    0x3c(%rsp),%ebp
  lea    (%rcx,%r10,1),%r11
  xor    %esi,%esi
  lea    0x8(%rcx),%r15
  nopl   0x0(%rax)
L68:
  movsd  (%rcx,%rsi,8),%xmm1
  movapd %xmm3,%xmm0
  mov    (%r9,%rsi,8),%rax
  mulsd  %xmm1,%xmm0
  addsd  (%rbx,%rsi,8),%xmm0
  movsd  %xmm0,(%rbx,%rsi,8)
  cmp    %r15,%rax
  je     L6
  cmp    $0x1,%r8d
  je     L6
  movapd %xmm1,%xmm2
  xor    %edx,%edx
  unpcklpd %xmm2,%xmm2
  nopl   0x0(%rax,%rax,1)
L29:
  movupd (%rcx,%rdx,1),%xmm0
  movupd (%rax,%rdx,1),%xmm4
  mulpd  %xmm2,%xmm0
  addpd  %xmm4,%xmm0
  movups %xmm0,(%rax,%rdx,1)
  add    $0x10,%rdx
  cmp    %rdi,%rdx
  jne    L29
  cmp    %r8d,%ebp
  je     L61
  mulsd  (%r11),%xmm1
  add    %r10,%rax
  addsd  (%rax),%xmm1
  movsd  %xmm1,(%rax)
L61:
  lea    0x1(%rsi),%rax
  cmp    %rsi,%r13
  je     L51
L86:
  mov    %rax,%rsi
  jmp    L68
  nopw   0x0(%rax,%rax,1)
L6:
  xor    %edx,%edx
  nopw   0x0(%rax,%rax,1)
L88:
  movsd  (%rcx,%rdx,8),%xmm0
  mov    %rdx,%r12
  mulsd  %xmm1,%xmm0
  addsd  (%rax,%rdx,8),%xmm0
  movsd  %xmm0,(%rax,%rdx,8)
  add    $0x1,%rdx
  cmp    %r12,%r13
  jne    L88
  lea    0x1(%rsi),%rax
  cmp    %rsi,%r13
  jne    L86
  nopl   0x0(%rax,%rax,1)
L51:
  mov    0x18(%rsp),%rbp
  add    $0x1,%r14
  cmp    0x10(%rsp),%r14
  jne    L85
L10:
  add    $0x48,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void crosscheck(double **x, double **ystar, int **ok, int n, int q, int j, double **xpx, double *xpy) {
  int i, k, l, okij;
  double *xrow, ystarij, xk, xl;
  for (k = 0; k < q; k++) {
    xpy[k] = 0.0;
    for (l = 0; l < q; l++) {
      xpx[k][l] = 0.0;
    }
  }
  for (i = 0; i < n; i++) {
    okij = ok[i][j];
    if (okij) {
      xrow = x[i];
      ystarij = ystar[i][j];
      for (k = 0; k < q; k++) {
        xk = xrow[k];
        xpy[k] += xk * ystarij;
        for (l = 0; l < q; l++) {
          xl = xrow[l];
          xpx[k][l] += xk * xl;
        }
      }
    }
  }
  return;
}
```