user: What would the C source look like for the assembly code provided here?

```asm
<dwt_deinterleave_v>:
  endbr64
  push   %r12
  mov    %edx,%r10d
  mov    %ecx,%edx
  push   %rbp
  push   %rbx
  test   %ecx,%ecx
  jle    L102
  cmp    $0x1,%r8d
  jne    L0
  movslq %ecx,%rax
  movslq %r9d,%r11
  lea    -0x1(%rcx),%ebx
  lea    (%rdi,%r11,4),%rcx
  lea    -0x1(%r11,%rax,2),%r11
  lea    (%rdi,%r11,4),%r11
  lea    (%rsi,%rax,4),%rax
  cmp    %r11,%rsi
  setae  %r11b
  cmp    %rax,%rcx
  setae  %al
  or     %al,%r11b
  je     L170
  cmp    $0x3,%ebx
  jbe    L170
  mov    %ebx,%r11d
  xor    %eax,%eax
  shr    $0x2,%r11d
  shl    $0x4,%r11
  nopl   (%rax)
L66:
  movdqu (%rcx,%rax,2),%xmm0
  movdqu 0x10(%rcx,%rax,2),%xmm1
  shufps $0x88,%xmm1,%xmm0
  movups %xmm0,(%rsi,%rax,1)
  add    $0x10,%rax
  cmp    %r11,%rax
  jne    L66
  mov    %ebx,%eax
  and    $0xfffffffc,%eax
  lea    (%rax,%rax,1),%ecx
  mov    %eax,%ebp
  lea    (%r9,%rcx,1),%r11d
  lea    0x0(,%rbp,4),%rbx
  movslq %r11d,%r11
  mov    (%rdi,%r11,4),%r11d
  mov    %r11d,(%rsi,%rbp,4)
  lea    0x1(%rax),%r11d
  cmp    %r11d,%edx
  jle    L102
  lea    0x2(%rcx,%r9,1),%r11d
  movslq %r11d,%r11
  mov    (%rdi,%r11,4),%r11d
  mov    %r11d,0x4(%rsi,%rbx,1)
  lea    0x2(%rax),%r11d
  cmp    %r11d,%edx
  jle    L102
  lea    0x4(%rcx,%r9,1),%r11d
  add    $0x3,%eax
  movslq %r11d,%r11
  mov    (%rdi,%r11,4),%r11d
  mov    %r11d,0x8(%rsi,%rbx,1)
  cmp    %eax,%edx
  jle    L102
  lea    0x6(%rcx,%r9,1),%eax
  cltq
  mov    (%rdi,%rax,4),%eax
  mov    %eax,0xc(%rsi,%rbx,1)
L102:
  test   %r10d,%r10d
  jle    L210
  cmp    $0x1,%r8d
  jne    L155
  movslq %r9d,%r11
  movslq %r10d,%rax
  lea    -0x1(%r10),%r8d
  movslq %edx,%r12
  neg    %r11
  lea    (%rsi,%r12,4),%rbx
  shl    $0x2,%r11
  lea    (%r11,%rax,8),%rbp
  lea    0x4(%rdi,%r11,1),%rcx
  add    %rdi,%rbp
  cmp    %rbp,%rbx
  setae  %bpl
  add    %r12,%rax
  lea    (%rsi,%rax,4),%rax
  cmp    %rax,%rcx
  setae  %al
  or     %al,%bpl
  je     L58
  cmp    $0x3,%r8d
  jbe    L58
  mov    %r8d,%r11d
  xor    %eax,%eax
  shr    $0x2,%r11d
  shl    $0x4,%r11
  nopl   0x0(%rax)
L93:
  movdqu (%rcx,%rax,2),%xmm0
  movdqu 0x10(%rcx,%rax,2),%xmm2
  shufps $0x88,%xmm2,%xmm0
  movups %xmm0,(%rbx,%rax,1)
  add    $0x10,%rax
  cmp    %r11,%rax
  jne    L93
  and    $0xfffffffc,%r8d
  lea    (%r8,%r8,1),%eax
  lea    0x1(%rax),%ecx
  sub    %r9d,%ecx
  movslq %ecx,%rcx
  mov    (%rdi,%rcx,4),%r11d
  lea    (%rdx,%r8,1),%ecx
  movslq %ecx,%rcx
  mov    %r11d,(%rsi,%rcx,4)
  lea    0x1(%r8),%ecx
  cmp    %ecx,%r10d
  jle    L210
  lea    0x3(%rax),%r11d
  add    %edx,%ecx
  sub    %r9d,%r11d
  movslq %ecx,%rcx
  movslq %r11d,%r11
  mov    (%rdi,%r11,4),%r11d
  mov    %r11d,(%rsi,%rcx,4)
  lea    0x2(%r8),%ecx
  cmp    %ecx,%r10d
  jle    L210
  lea    0x5(%rax),%r11d
  add    %edx,%ecx
  add    $0x3,%r8d
  sub    %r9d,%r11d
  movslq %ecx,%rcx
  movslq %r11d,%r11
  mov    (%rdi,%r11,4),%r11d
  mov    %r11d,(%rsi,%rcx,4)
  cmp    %r8d,%r10d
  jle    L210
  add    $0x7,%eax
  add    %r8d,%edx
  sub    %r9d,%eax
  movslq %edx,%rdx
  cltq
  mov    (%rdi,%rax,4),%eax
  mov    %eax,(%rsi,%rdx,4)
L210:
  pop    %rbx
  pop    %rbp
  pop    %r12
  ret
  xchg   %ax,%ax
L155:
  movslq %r8d,%r11
  imul   %edx,%r8d
  lea    -0x1(%r10),%ecx
  movslq %r9d,%r9
  mov    $0x1,%eax
  add    %rcx,%rcx
  shl    $0x2,%r11
  sub    %r9,%rax
  sub    %r9,%rcx
  movslq %r8d,%r8
  lea    (%rdi,%rax,4),%rax
  lea    (%rsi,%r8,4),%rdx
  lea    0xc(%rdi,%rcx,4),%rsi
L133:
  mov    (%rax),%ecx
  add    $0x8,%rax
  mov    %ecx,(%rdx)
  add    %r11,%rdx
  cmp    %rsi,%rax
  jne    L133
  pop    %rbx
  pop    %rbp
  pop    %r12
  ret
  nopl   (%rax)
L0:
  movslq %r9d,%r11
  lea    -0x1(%rdx),%ebp
  movslq %r8d,%rbx
  mov    %rsi,%rcx
  lea    (%rdi,%r11,4),%rax
  lea    (%r11,%rbp,2),%r11
  shl    $0x2,%rbx
  lea    0x8(%rdi,%r11,4),%rbp
  nopl   (%rax)
L43:
  mov    (%rax),%r11d
  add    $0x8,%rax
  mov    %r11d,(%rcx)
  add    %rbx,%rcx
  cmp    %rbp,%rax
  jne    L43
  jmp    L102
  nop
L170:
  mov    %edx,%ebx
  xor    %eax,%eax
  nopl   0x0(%rax)
L138:
  mov    (%rcx,%rax,8),%r11d
  mov    %r11d,(%rsi,%rax,4)
  add    $0x1,%rax
  cmp    %rbx,%rax
  jne    L138
  jmp    L102
  xchg   %ax,%ax
L58:
  mov    %r10d,%r10d
  add    %r11,%rdi
  xor    %eax,%eax
  nopl   0x0(%rax,%rax,1)
L119:
  mov    0x4(%rdi,%rax,8),%edx
  mov    %edx,(%rbx,%rax,4)
  add    $0x1,%rax
  cmp    %r10,%rax
  jne    L119
  pop    %rbx
  pop    %rbp
  pop    %r12
  ret
```

assistant: ```c
void dwt_deinterleave_v(int *a, int *b, int dn, int sn, int x, int cas) {
  int i;
  for (i = 0; i < sn; i++)
    b[i * x] = a[2 * i + cas];
  for (i = 0; i < dn; i++)
    b[(sn + i) * x] = a[(2 * i + 1 - cas)];
}
```