user: 下面的汇编指令对应的C源代码是什么:

```asm
<kernel_ludcmp>:
  endbr64
  push   %r15
  lea    -0x1(%rdi),%eax
  mov    %rcx,%r15
  push   %r14
  push   %r13
  mov    %r8,%r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %edi,-0x2c(%rsp)
  mov    %rdx,-0x28(%rsp)
  mov    %eax,-0x30(%rsp)
  test   %edi,%edi
  jle    L96
  lea    0x3e80(%rsi),%rbx
  mov    %rax,-0x38(%rsp)
  mov    %edi,%r14d
  xor    %r12d,%r12d
  mov    %rbx,-0x20(%rsp)
  mov    %rbx,%r9
  mov    %rsi,%rdi
  mov    %rsi,-0x40(%rsp)
  mov    %rcx,-0x18(%rsp)
  mov    %r8,-0x10(%rsp)
  nopl   0x0(%rax,%rax,1)
L86:
  mov    %r12d,%eax
  mov    %r12d,%ebx
  mov    -0x40(%rsp),%r11
  mov    %r12d,%r13d
  shr    %eax
  mov    %r12d,%ebp
  and    $0xfffffffe,%ebx
  mov    %r12,%r8
  sub    $0x1,%eax
  shl    $0x4,%rax
  lea    0x10(%rdi,%rax,1),%r10
  nopl   (%rax)
L65:
  movsd  (%rdi,%r8,8),%xmm1
  movslq %r8d,%rcx
  test   %r12,%r12
  je     L269
  cmp    $0x1,%r13d
  je     L92
  mov    %r11,%rdx
  mov    %rdi,%rax
  cs nopw 0x0(%rax,%rax,1)
L229:
  movsd  (%rdx),%xmm0
  movupd (%rax),%xmm4
  add    $0x10,%rax
  add    $0x7d00,%rdx
  movhpd -0x3e80(%rdx),%xmm0
  mulpd  %xmm4,%xmm0
  subsd  %xmm0,%xmm1
  unpckhpd %xmm0,%xmm0
  subsd  %xmm0,%xmm1
  cmp    %r10,%rax
  jne    L229
  movslq %ebx,%rax
  cmp    %ebp,%ebx
  je     L269
L221:
  imul   $0x3e80,%rax,%rdx
  add    %rsi,%rdx
  movsd  (%rdx,%rcx,8),%xmm0
  mulsd  (%rdi,%rax,8),%xmm0
  subsd  %xmm0,%xmm1
L269:
  movsd  %xmm1,(%rdi,%r8,8)
  add    $0x1,%r8
  add    $0x8,%r11
  cmp    %r8d,%r14d
  jg     L65
  cmp    -0x38(%rsp),%r12
  je     L76
  movsd  (%r9),%xmm0
  divsd  (%rsi),%xmm0
  movsd  %xmm0,(%r9)
  test   %r12,%r12
  je     L250
  lea    -0x1(%rbp),%r13d
  lea    0x8(%rsi),%rbx
  mov    $0x1,%r10d
  lea    0x3e88(%rsi),%r11
  add    $0x2,%r13
  lea    0x10(%r9),%r15
  nopl   (%rax)
L140:
  movsd  (%r9,%r10,8),%xmm1
  mov    %r10d,%ebp
  movslq %r10d,%rcx
  cmp    $0x1,%r10
  je     L20
  mov    %r10d,%eax
  mov    %rbx,%rdx
  shr    %eax
  lea    -0x1(%rax),%r8d
  mov    %r9,%rax
  shl    $0x4,%r8
  add    %r15,%r8
  nopl   0x0(%rax)
L99:
  movsd  (%rdx),%xmm0
  movupd (%rax),%xmm3
  add    $0x10,%rax
  add    $0x7d00,%rdx
  movhpd -0x3e80(%rdx),%xmm0
  mulpd  %xmm3,%xmm0
  subsd  %xmm0,%xmm1
  unpckhpd %xmm0,%xmm0
  subsd  %xmm0,%xmm1
  cmp    %rax,%r8
  jne    L99
  mov    %ebp,%eax
  and    $0xfffffffe,%eax
  and    $0x1,%ebp
  je     L231
L109:
  cltq
  imul   $0x3e80,%rax,%rdx
  add    %rsi,%rdx
  movsd  (%rdx,%rcx,8),%xmm0
  mulsd  (%r9,%rax,8),%xmm0
  subsd  %xmm0,%xmm1
L231:
  divsd  (%r11),%xmm1
  movsd  %xmm1,(%r9,%r10,8)
  add    $0x1,%r10
  add    $0x3e88,%r11
  add    $0x8,%rbx
  cmp    %r10,%r13
  jne    L140
L250:
  addq   $0x8,-0x40(%rsp)
  add    $0x1,%r12
  add    $0x3e80,%r9
  add    $0x3e80,%rdi
  jmp    L86
L20:
  xor    %eax,%eax
  jmp    L109
L92:
  xor    %eax,%eax
  jmp    L221
L76:
  mov    -0x28(%rsp),%r10
  mov    -0x10(%rsp),%r13
  mov    -0x2c(%rsp),%r9d
  mov    -0x18(%rsp),%r15
  movsd  (%r10),%xmm0
  movsd  %xmm0,0x0(%r13)
  cmp    $0x1,%r9d
  jle    L267
  mov    -0x20(%rsp),%rdx
  mov    $0x1,%edi
  mov    $0x1,%r8d
  nopl   0x0(%rax)
L148:
  test   %edi,%edi
  mov    %r8d,%r11d
  movsd  (%r10,%rdi,8),%xmm1
  cmovg  %edi,%r11d
  cmp    $0x1,%rdi
  je     L156
  mov    %r11d,%ecx
  xor    %eax,%eax
  shr    %ecx
  shl    $0x4,%rcx
  nopl   0x0(%rax)
L32:
  movupd 0x0(%r13,%rax,1),%xmm0
  movupd (%rdx,%rax,1),%xmm5
  add    $0x10,%rax
  mulpd  %xmm5,%xmm0
  subsd  %xmm0,%xmm1
  unpckhpd %xmm0,%xmm0
  subsd  %xmm0,%xmm1
  cmp    %rax,%rcx
  jne    L32
  mov    %r11d,%eax
  and    $0xfffffffe,%eax
  and    $0x1,%r11d
  je     L210
L52:
  cltq
  movsd  0x0(%r13,%rax,8),%xmm0
  mulsd  (%rdx,%rax,8),%xmm0
  subsd  %xmm0,%xmm1
L210:
  movsd  %xmm1,0x0(%r13,%rdi,8)
  add    $0x1,%rdi
  add    $0x3e80,%rdx
  cmp    %edi,%r9d
  jg     L148
L267:
  movslq -0x30(%rsp),%rdi
  xor    %r9d,%r9d
  imul   $0x3e88,%rdi,%rax
  imul   $0x3e80,%rdi,%rdx
  add    %rsi,%rdx
  lea    0x8(%rsi,%rax,1),%rsi
  movslq -0x2c(%rsp),%rax
  mov    %rax,%r10
  lea    (%r15,%rax,8),%rcx
  mov    %eax,%r8d
  nopl   0x0(%rax,%rax,1)
L147:
  movsd  0x0(%r13,%rdi,8),%xmm0
  mov    %r8d,%eax
  cmp    %r8d,%r10d
  jle    L232
  mov    %r10d,%r11d
  sub    %edi,%r11d
  cmp    $0x2,%r11d
  je     L238
  mov    %r9d,%r11d
  xor    %eax,%eax
  shr    %r11d
  shl    $0x4,%r11
  nopw   0x0(%rax,%rax,1)
L160:
  movupd (%rcx,%rax,1),%xmm1
  movupd (%rsi,%rax,1),%xmm6
  add    $0x10,%rax
  mulpd  %xmm6,%xmm1
  subsd  %xmm1,%xmm0
  unpckhpd %xmm1,%xmm1
  subsd  %xmm1,%xmm0
  cmp    %r11,%rax
  jne    L160
  mov    %r9d,%r11d
  and    $0xfffffffe,%r11d
  lea    (%r8,%r11,1),%eax
  cmp    %r9d,%r11d
  je     L232
L238:
  cltq
  movsd  (%r15,%rax,8),%xmm1
  mulsd  (%rdx,%rax,8),%xmm1
  subsd  %xmm1,%xmm0
L232:
  sub    $0x1,%rdi
  add    $0x1,%r9d
  sub    $0x1,%r8d
  sub    $0x8,%rcx
  divsd  -0x8(%rsi),%xmm0
  sub    $0x3e80,%rdx
  movsd  %xmm0,(%rcx)
  sub    $0x3e88,%rsi
  test   %edi,%edi
  jns    L147
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L156:
  xor    %eax,%eax
  jmp    L52
L96:
  mov    -0x30(%rsp),%eax
  test   %eax,%eax
  jns    L267
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void kernel_ludcmp(int n, double A[2000 + 0][2000 + 0], double b[2000 + 0], double x[2000 + 0], double y[2000 + 0]) {
  int i, j, k;
  double w;
#pragma scop
  for (i = 0; i < n; i++) {
    for (j = 0; j < i; j++) {
      w = A[i][j];
      for (k = 0; k < j; k++) {
        w -= A[i][k] * A[k][j];
      }
      A[i][j] = w / A[j][j];
    }
    for (j = i; j < n; j++) {
      w = A[i][j];
      for (k = 0; k < i; k++) {
        w -= A[i][k] * A[k][j];
      }
      A[i][j] = w;
    }
  }
  for (i = 0; i < n; i++) {
    w = b[i];
    for (j = 0; j < i; j++)
      w -= A[i][j] * y[j];
    y[i] = w;
  }
  for (i = n - 1; i >= 0; i--) {
    w = y[i];
    for (j = i + 1; j < n; j++)
      w -= A[i][j] * x[j];
    x[i] = w / A[i][i];
  }
#pragma endscop
}
```