user: What is the c source code of the assembly code below?

```asm
<_dmvec_daxpy>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbx
  sub    $0x48,%rsp
  mov    %rdi,-0x48(%rbp)
  mov    %rsi,-0x50(%rbp)
  mov    %rdx,-0x58(%rbp)
  movsd  %xmm0,-0x60(%rbp)
  mov    %ecx,-0x64(%rbp)
  mov    %r8d,-0x68(%rbp)
  mov    %r9d,-0x6c(%rbp)
  mov    -0x50(%rbp),%rax
  mov    %rax,-0x38(%rbp)
  mov    $0x0,%ebx
  jmp    L45
L41:
  mov    -0x38(%rbp),%r12
  mov    -0x68(%rbp),%eax
  cltq
  shl    $0x3,%rax
  lea    (%r12,%rax,1),%r13
  mov    -0x68(%rbp),%eax
  cltq
  shl    $0x3,%rax
  lea    0x0(%r13,%rax,1),%r14
  mov    -0x68(%rbp),%eax
  cltq
  shl    $0x3,%rax
  lea    (%r14,%rax,1),%r15
  mov    -0x60(%rbp),%rdx
  mov    -0x6c(%rbp),%r8d
  mov    -0x58(%rbp),%rdi
  mov    -0x64(%rbp),%esi
  mov    -0x48(%rbp),%rax
  sub    $0x8,%rsp
  mov    0x10(%rbp),%ecx
  push   %rcx
  movq   %rdx,%xmm0
  mov    %r8d,%r9d
  mov    %rdi,%r8
  mov    %r13,%rcx
  mov    %r12,%rdx
  mov    %rax,%rdi
  call   <_inner_vec2_daxpy@plt>
  add    $0x10,%rsp
  mov    -0x6c(%rbp),%eax
  add    %eax,%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x58(%rbp)
  mov    -0x60(%rbp),%rdx
  mov    -0x6c(%rbp),%r8d
  mov    -0x58(%rbp),%rdi
  mov    -0x64(%rbp),%esi
  mov    -0x48(%rbp),%rax
  sub    $0x8,%rsp
  mov    0x10(%rbp),%ecx
  push   %rcx
  movq   %rdx,%xmm0
  mov    %r8d,%r9d
  mov    %rdi,%r8
  mov    %r15,%rcx
  mov    %r14,%rdx
  mov    %rax,%rdi
  call   <_inner_vec2_daxpy@plt>
  add    $0x10,%rsp
  mov    -0x6c(%rbp),%eax
  add    %eax,%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x58(%rbp)
  mov    -0x68(%rbp),%eax
  shl    $0x2,%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x38(%rbp)
  add    $0x4,%ebx
L45:
  mov    0x18(%rbp),%eax
  sub    $0x3,%eax
  cmp    %eax,%ebx
  jl     L41
  cmp    0x18(%rbp),%ebx
  je     L8
  mov    0x18(%rbp),%eax
  sub    $0x1,%eax
  cmp    %eax,%ebx
  jge    L53
  mov    -0x38(%rbp),%r12
  mov    -0x68(%rbp),%eax
  cltq
  shl    $0x3,%rax
  lea    (%r12,%rax,1),%r13
  mov    -0x60(%rbp),%rdx
  mov    -0x6c(%rbp),%r8d
  mov    -0x58(%rbp),%rdi
  mov    -0x64(%rbp),%esi
  mov    -0x48(%rbp),%rax
  sub    $0x8,%rsp
  mov    0x10(%rbp),%ecx
  push   %rcx
  movq   %rdx,%xmm0
  mov    %r8d,%r9d
  mov    %rdi,%r8
  mov    %r13,%rcx
  mov    %r12,%rdx
  mov    %rax,%rdi
  call   <_inner_vec2_daxpy@plt>
  add    $0x10,%rsp
  mov    -0x6c(%rbp),%eax
  add    %eax,%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x58(%rbp)
  mov    -0x68(%rbp),%eax
  add    %eax,%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x38(%rbp)
  add    $0x2,%ebx
L53:
  cmp    0x18(%rbp),%ebx
  jge    L21
  mov    -0x38(%rbp),%r12
  mov    -0x60(%rbp),%rcx
  mov    -0x6c(%rbp),%edi
  mov    -0x58(%rbp),%rdx
  mov    -0x64(%rbp),%esi
  mov    -0x48(%rbp),%rax
  mov    0x10(%rbp),%r9d
  movq   %rcx,%xmm0
  mov    %edi,%r8d
  mov    %rdx,%rcx
  mov    %r12,%rdx
  mov    %rax,%rdi
  call   <_inner_vec_daxpy@plt>
  mov    -0x6c(%rbp),%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x58(%rbp)
  mov    -0x68(%rbp),%eax
  cltq
  shl    $0x3,%rax
  add    %rax,-0x38(%rbp)
  add    $0x1,%ebx
  jmp    L21
L8:
  nop
L21:
  lea    -0x28(%rbp),%rsp
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  pop    %rbp
  ret
```

assistant: ```c
void _dmvec_daxpy(double *Yc, const double *Aroot, const double *Xc, double alpha, int incY, int ldA, int incX, int nRE, int nC) {
  register int j, k;
  register const double *a0, *a1, *a2, *a3;
  const double *Ac;
  Ac = Aroot;
  for (j = 0; j < nC - 3; j += 4) {
    a0 = Ac;
    a1 = a0 + ldA;
    a2 = a1 + ldA;
    a3 = a2 + ldA;
    _inner_vec2_daxpy(Yc, incY, a0, a1, Xc, incX, alpha, nRE);
    Xc += 2 * incX;
    _inner_vec2_daxpy(Yc, incY, a2, a3, Xc, incX, alpha, nRE);
    Xc += 2 * incX;
    Ac += 4 * ldA;
  }
  if (j == nC)
    return;
  if (j < nC - 1) {
    a0 = Ac;
    a1 = a0 + ldA;
    _inner_vec2_daxpy(Yc, incY, a0, a1, Xc, incX, alpha, nRE);
    Xc += 2 * incX;
    Ac += 2 * ldA;
    j += 2;
  }
  if (j < nC) {
    a0 = Ac;
    _inner_vec_daxpy(Yc, incY, a0, Xc, incX, alpha, nRE);
    Xc += incX;
    Ac += ldA;
    j++;
  }
}
```