user: 这段汇编代码用C语言表示是什么样的：

```asm
<ff_dm_quad>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x88,%rsp
  mov    0xc0(%rsp),%rax
  mov    %rdi,0x40(%rsp)
  mov    %esi,0x4c(%rsp)
  mov    %rax,0x30(%rsp)
  mov    0xc8(%rsp),%rax
  mov    %r9,0x18(%rsp)
  mov    %rax,0x38(%rsp)
  movsd  %xmm0,0x10(%rsp)
  mov    %fs:0x28,%rax
  mov    %rax,0x78(%rsp)
  xor    %eax,%eax
  test   %rdi,%rdi
  je     L73
  cmp    $0x1,%rdi
  je     L40
  lea    0x0(,%rdi,8),%rax
  mov    %rdx,%rbp
  lea    0x60(%rsp),%rbx
  movq   $0x0,(%rsp)
  lea    (%r8,%rax,1),%r12
  mov    %rax,0x50(%rsp)
  lea    (%rcx,%rax,1),%r14
  mov    $0x1,%r15d
  mov    %r12,0x8(%rsp)
  cs nopw 0x0(%rax,%rax,1)
L171:
  lea    (%r15,%r15,2),%rdx
  cmpq   $0x0,0x18(%rsp)
  mov    %rbp,%rax
  lea    0x0(%rbp,%rdx,8),%r13
  je     L131
  mov    0x4c(%rsp),%eax
  xor    %r10d,%r10d
  mov    %r14,%r12
  mov    %r10,%r14
  test   %eax,%eax
  jne    L86
  nopl   (%rax)
L6:
  movsd  (%r12,%r14,8),%xmm2
  pxor   %xmm7,%xmm7
  comisd %xmm7,%xmm2
  movsd  %xmm2,0x20(%rsp)
  jbe    L46
  mov    0x8(%rsp),%rax
  mov    %rbx,%rdx
  mov    %r13,%rdi
  movsd  (%rax,%r14,8),%xmm4
  lea    (%r14,%r14,2),%rax
  lea    0x0(%rbp,%rax,8),%rsi
  movsd  %xmm4,0x28(%rsp)
  call   <distance_delta@plt>
  mov    0x18(%rsp),%r8
  mov    %rbx,%rcx
  mov    %rbp,%rdx
  movsd  0x10(%rsp),%xmm5
  movapd %xmm0,%xmm1
  mov    %r14,%rsi
  mov    %r15,%rdi
  movsd  0x28(%rsp),%xmm4
  movapd %xmm0,%xmm3
  movsd  0x20(%rsp),%xmm2
  movapd %xmm5,%xmm0
  mulsd  %xmm4,%xmm0
  subsd  %xmm2,%xmm3
  mulsd  %xmm3,%xmm0
  mulsd  %xmm3,%xmm0
  addsd  (%rsp),%xmm0
  movsd  %xmm0,(%rsp)
  movapd %xmm5,%xmm0
  addsd  %xmm5,%xmm0
  mulsd  %xmm4,%xmm0
  mulsd  %xmm3,%xmm0
  divsd  %xmm1,%xmm0
  call   <add_grad@plt>
L46:
  add    $0x1,%r14
  cmp    %r14,%r15
  jne    L6
L60:
  mov    %r12,%r14
L32:
  mov    0x50(%rsp),%rcx
  add    $0x1,%r15
  add    %rcx,0x8(%rsp)
  add    %rcx,%r14
  cmp    %r15,0x40(%rsp)
  jne    L171
L121:
  mov    0x78(%rsp),%rax
  sub    %fs:0x28,%rax
  jne    L141
  movsd  (%rsp),%xmm0
  add    $0x88,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L86:
  movsd  (%r12,%r14,8),%xmm2
  pxor   %xmm7,%xmm7
  comisd %xmm7,%xmm2
  movsd  %xmm2,0x20(%rsp)
  jbe    L20
  mov    0x8(%rsp),%rax
  mov    0x38(%rsp),%r8
  mov    %rbx,%rdx
  mov    %r13,%rdi
  mov    0x30(%rsp),%rcx
  movsd  (%rax,%r14,8),%xmm4
  lea    (%r14,%r14,2),%rax
  lea    0x0(%rbp,%rax,8),%rsi
  movsd  %xmm4,0x28(%rsp)
  call   <distance_delta_periodic@plt>
  mov    0x18(%rsp),%r8
  mov    %rbx,%rcx
  mov    %rbp,%rdx
  movsd  0x10(%rsp),%xmm6
  movapd %xmm0,%xmm1
  mov    %r14,%rsi
  mov    %r15,%rdi
  movsd  0x28(%rsp),%xmm4
  movapd %xmm0,%xmm3
  movsd  0x20(%rsp),%xmm2
  movapd %xmm6,%xmm0
  mulsd  %xmm4,%xmm0
  subsd  %xmm2,%xmm3
  mulsd  %xmm3,%xmm0
  mulsd  %xmm3,%xmm0
  addsd  (%rsp),%xmm0
  movsd  %xmm0,(%rsp)
  movapd %xmm6,%xmm0
  addsd  %xmm6,%xmm0
  mulsd  %xmm4,%xmm0
  mulsd  %xmm3,%xmm0
  divsd  %xmm1,%xmm0
  call   <add_grad@plt>
L20:
  add    $0x1,%r14
  cmp    %r15,%r14
  jne    L86
  jmp    L60
  nopl   (%rax)
L131:
  mov    0x4c(%rsp),%edx
  test   %edx,%edx
  jne    L94
  xor    %ecx,%ecx
  mov    %rbp,0x58(%rsp)
  mov    %rbx,%r12
  mov    %r13,%rbp
  mov    %rax,%rbx
  mov    %rcx,%r13
  nop
L24:
  movsd  (%r14,%r13,8),%xmm3
  pxor   %xmm7,%xmm7
  comisd %xmm7,%xmm3
  movsd  %xmm3,0x20(%rsp)
  jbe    L199
  mov    0x8(%rsp),%rax
  mov    %r12,%rdx
  mov    %rbx,%rsi
  mov    %rbp,%rdi
  movsd  (%rax,%r13,8),%xmm1
  movsd  %xmm1,0x28(%rsp)
  call   <distance_delta@plt>
  movsd  0x28(%rsp),%xmm1
  mulsd  0x10(%rsp),%xmm1
  movsd  0x20(%rsp),%xmm3
  movapd %xmm0,%xmm2
  subsd  %xmm3,%xmm2
  movapd %xmm1,%xmm0
  mulsd  %xmm2,%xmm0
  mulsd  %xmm2,%xmm0
  addsd  (%rsp),%xmm0
  movsd  %xmm0,(%rsp)
L199:
  add    $0x1,%r13
  add    $0x18,%rbx
  cmp    %r15,%r13
  jne    L24
  mov    0x58(%rsp),%rbp
  mov    %r12,%rbx
  jmp    L32
  nop
L94:
  xor    %r10d,%r10d
  mov    %rbp,0x58(%rsp)
  mov    %rbx,%r12
  mov    %r14,%rbp
  mov    %r10,%rbx
  mov    %rax,%r14
  nopl   0x0(%rax)
L84:
  movsd  0x0(%rbp,%rbx,8),%xmm3
  pxor   %xmm5,%xmm5
  comisd %xmm5,%xmm3
  movsd  %xmm3,0x20(%rsp)
  jbe    L16
  mov    0x8(%rsp),%rax
  mov    0x38(%rsp),%r8
  mov    %r12,%rdx
  mov    %r14,%rsi
  mov    0x30(%rsp),%rcx
  mov    %r13,%rdi
  movsd  (%rax,%rbx,8),%xmm1
  movsd  %xmm1,0x28(%rsp)
  call   <distance_delta_periodic@plt>
  movsd  0x28(%rsp),%xmm1
  mulsd  0x10(%rsp),%xmm1
  movsd  0x20(%rsp),%xmm3
  movapd %xmm0,%xmm2
  subsd  %xmm3,%xmm2
  movapd %xmm1,%xmm0
  mulsd  %xmm2,%xmm0
  mulsd  %xmm2,%xmm0
  addsd  (%rsp),%xmm0
  movsd  %xmm0,(%rsp)
L16:
  add    $0x1,%rbx
  add    $0x18,%r14
  cmp    %r15,%rbx
  jne    L84
  mov    %rbp,%r14
  mov    %r12,%rbx
  mov    0x58(%rsp),%rbp
  jmp    L32
L73:
  pxor   %xmm6,%xmm6
  movsd  %xmm6,(%rsp)
  jmp    L121
L40:
  pxor   %xmm4,%xmm4
  movsd  %xmm4,(%rsp)
  jmp    L121
L141:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
double ff_dm_quad(size_t natom, int periodic, double *cor, double *dm0, double *dmk, double amp, double *gradient, double *matrix, double *reciprocal) {
  size_t i, j;
  double delta[3], d, d0, k, tmp, result;
  result = 0.0;
  for (i = 0; i < natom; i++) {
    for (j = 0; j < i; j++) {
      d0 = dm0[i * natom + j];
      k = dmk[i * natom + j];
      if (d0 > 0) {
        if (periodic) {
          d = distance_delta_periodic(cor + 3 * i, cor + 3 * j, delta, matrix, reciprocal);
        } else {
          d = distance_delta(cor + 3 * i, cor + 3 * j, delta);
        }
        tmp = (d - d0);
        result += amp * k * tmp * tmp;
        if (gradient != NULL) {
          tmp = 2 * amp * k * tmp / d;
          add_grad(i, j, tmp, cor, delta, gradient);
        }
      }
    }
  }
  return result;
}
```