user: Translate the below assembly code into C programming language:

```asm
<lubksb>:
  endbr64
  test   %esi,%esi
  jle    L146
  push   %r13
  mov    %rdx,%r9
  mov    $0x1,%r8d
  mov    %rcx,%rdx
  push   %r12
  xor    %r10d,%r10d
  mov    $0x1,%eax
  pxor   %xmm2,%xmm2
  push   %rbp
  push   %rbx
  nopw   0x0(%rax,%rax,1)
L150:
  movslq (%r9,%r8,4),%rcx
  movsd  (%rdx,%r8,8),%xmm1
  lea    (%rdx,%rcx,8),%rcx
  movsd  (%rcx),%xmm0
  movsd  %xmm1,(%rcx)
  test   %r10d,%r10d
  jne    L212
  ucomisd %xmm2,%xmm0
  jp     L59
  je     L163
L59:
  mov    %eax,%r10d
L163:
  add    $0x1,%eax
  movsd  %xmm0,(%rdx,%r8,8)
  cmp    %esi,%eax
  jg     L142
  add    $0x1,%r8
  jmp    L150
  nopl   (%rax)
L212:
  cmp    %r10d,%eax
  jle    L126
  mov    %eax,%r12d
  mov    (%rdi,%r8,8),%rbp
  sub    %r10d,%r12d
  cmp    $0x1,%r12d
  je     L164
  movslq %r10d,%r11
  mov    %r12d,%ebx
  xor    %ecx,%ecx
  shl    $0x3,%r11
  shr    %ebx
  lea    0x0(%rbp,%r11,1),%r13
  shl    $0x4,%rbx
  add    %rdx,%r11
  nopl   0x0(%rax,%rax,1)
L112:
  movupd 0x0(%r13,%rcx,1),%xmm1
  movupd (%r11,%rcx,1),%xmm4
  add    $0x10,%rcx
  mulpd  %xmm4,%xmm1
  subsd  %xmm1,%xmm0
  unpckhpd %xmm1,%xmm1
  subsd  %xmm1,%xmm0
  cmp    %rbx,%rcx
  jne    L112
  mov    %r12d,%r11d
  and    $0xfffffffe,%r11d
  lea    (%r11,%r10,1),%ecx
  cmp    %r11d,%r12d
  je     L126
L99:
  movslq %ecx,%rcx
  movsd  0x0(%rbp,%rcx,8),%xmm1
  mulsd  (%rdx,%rcx,8),%xmm1
  subsd  %xmm1,%xmm0
L126:
  lea    0x1(%rax),%ecx
  movsd  %xmm0,(%rdx,%r8,8)
  cmp    %ecx,%esi
  jl     L142
  movslq %r10d,%rbx
  movslq %ecx,%rax
  sub    %r10d,%ecx
  shl    $0x3,%rbx
  lea    (%rdx,%rbx,1),%r11
  nopw   0x0(%rax,%rax,1)
L152:
  movslq (%r9,%rax,4),%r8
  movsd  (%rdx,%rax,8),%xmm1
  lea    (%rdx,%r8,8),%r8
  movsd  (%r8),%xmm0
  movsd  %xmm1,(%r8)
  cmp    %eax,%r10d
  jge    L104
  mov    (%rdi,%rax,8),%rbp
  cmp    $0x1,%ecx
  je     L94
  mov    %ecx,%r12d
  lea    0x0(%rbp,%rbx,1),%r13
  xor    %r8d,%r8d
  shr    %r12d
  shl    $0x4,%r12
  nopl   0x0(%rax,%rax,1)
L141:
  movupd 0x0(%r13,%r8,1),%xmm1
  movupd (%r11,%r8,1),%xmm5
  add    $0x10,%r8
  mulpd  %xmm5,%xmm1
  subsd  %xmm1,%xmm0
  unpckhpd %xmm1,%xmm1
  subsd  %xmm1,%xmm0
  cmp    %r8,%r12
  jne    L141
  mov    %ecx,%r12d
  and    $0xfffffffe,%r12d
  lea    (%r12,%r10,1),%r8d
  cmp    %r12d,%ecx
  je     L104
L189:
  movslq %r8d,%r8
  movsd  0x0(%rbp,%r8,8),%xmm1
  mulsd  (%rdx,%r8,8),%xmm1
  subsd  %xmm1,%xmm0
L104:
  movsd  %xmm0,(%rdx,%rax,8)
  add    $0x1,%rax
  add    $0x1,%ecx
  cmp    %eax,%esi
  jge    L152
L142:
  movslq %esi,%rax
  lea    0x1(%rsi),%r10d
  xor    %r8d,%r8d
  lea    0x8(,%rax,8),%r11
  nopl   0x0(%rax,%rax,1)
L10:
  mov    %r11,%r9
  mov    %r10d,%eax
  sub    $0x8,%r11
  movsd  -0x8(%rdx,%r9,1),%xmm0
  mov    -0x8(%rdi,%r9,1),%rbx
  cmp    %r10d,%esi
  jl     L29
  cmp    $0x1,%r8d
  je     L162
  mov    %r8d,%ecx
  lea    (%rbx,%r9,1),%r12
  lea    (%rdx,%r9,1),%rbp
  xor    %eax,%eax
  shr    %ecx
  shl    $0x4,%rcx
  nopl   0x0(%rax)
L158:
  movupd 0x0(%rbp,%rax,1),%xmm1
  movupd (%r12,%rax,1),%xmm3
  add    $0x10,%rax
  mulpd  %xmm3,%xmm1
  subsd  %xmm1,%xmm0
  unpckhpd %xmm1,%xmm1
  subsd  %xmm1,%xmm0
  cmp    %rax,%rcx
  jne    L158
  mov    %r8d,%ecx
  and    $0xfffffffe,%ecx
  lea    (%r10,%rcx,1),%eax
  cmp    %r8d,%ecx
  je     L29
L162:
  cltq
  movsd  (%rdx,%rax,8),%xmm1
  mulsd  (%rbx,%rax,8),%xmm1
  subsd  %xmm1,%xmm0
L29:
  add    $0x1,%r8d
  divsd  (%rbx,%r11,1),%xmm0
  sub    $0x1,%r10d
  movsd  %xmm0,-0x8(%rdx,%r9,1)
  cmp    %esi,%r8d
  jne    L10
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  ret
L164:
  mov    %r10d,%ecx
  jmp    L99
L94:
  mov    %r10d,%r8d
  jmp    L189
L146:
  ret
```

assistant: ```c
void lubksb(a, n, indx, b) double **a, b[];
int n, indx[];
{
  int i, ii = 0, ip, j;
  double sum;
  for (i = 1; i <= n; i++) {
    ip = indx[i];
    sum = b[ip];
    b[ip] = b[i];
    if (ii) {
      for (j = ii; j <= i - 1; j++)
        sum -= a[i][j] * b[j];
    } else if (sum) {
      ii = i;
    }
    b[i] = sum;
  }
  for (i = n; i >= 1; i--) {
    sum = b[i];
    for (j = i + 1; j <= n; j++)
      sum -= a[i][j] * b[j];
    b[i] = sum / a[i][i];
  }
}
```