user: Demonstrate the C code that generates the assembly output below:

```asm
<cosqb1>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  mov    %rdx,%r13
  lea    0x1(%rdi),%edx
  mov    %edx,%eax
  push   %r12
  mov    %rcx,%r12
  push   %rbp
  shr    $0x1f,%eax
  mov    %rsi,%rbp
  push   %rbx
  add    %edx,%eax
  mov    %edi,%ebx
  sar    %eax
  mov    %eax,%r14d
  sub    $0x78,%rsp
  cmp    $0x2,%edi
  jle    L37
  lea    -0x3(%rdi),%ecx
  lea    0x8(%rsi),%rax
  xor    %edx,%edx
  shr    %ecx
  add    $0x1,%ecx
  nop
L126:
  movupd (%rax),%xmm0
  add    $0x1,%edx
  add    $0x10,%rax
  movapd %xmm0,%xmm1
  movapd %xmm0,%xmm2
  shufpd $0x1,%xmm0,%xmm1
  addpd  %xmm1,%xmm2
  subpd  %xmm1,%xmm0
  movsd  %xmm2,%xmm0
  movups %xmm0,-0x10(%rax)
  cmp    %ecx,%edx
  jb     L126
L37:
  movsd  0x0(%rbp),%xmm0
  mov    %ebx,%eax
  and    $0x1,%eax
  addsd  %xmm0,%xmm0
  mov    %eax,0x40(%rsp)
  movsd  %xmm0,0x0(%rbp)
  jne    L120
  movslq %ebx,%rax
  mov    %r12,%rdx
  mov    %rbp,%rsi
  mov    %ebx,%edi
  mov    %rax,0x18(%rsp)
  lea    -0x8(%rbp,%rax,8),%rax
  movsd  (%rax),%xmm0
  addsd  %xmm0,%xmm0
  movsd  %xmm0,(%rax)
  call   <rfftb@plt>
  cmp    $0x2,%ebx
  jle    L168
L77:
  mov    0x18(%rsp),%rax
  lea    -0x1(%r14),%edx
  cmp    $0x2,%ebx
  lea    0x18(%rbp),%r10
  mov    %edx,0x14(%rsp)
  lea    0x10(%r13),%r11
  lea    0x0(,%rax,8),%rcx
  mov    %r10,0x48(%rsp)
  lea    -0x8(%rcx),%rax
  mov    %r11,0x68(%rsp)
  lea    (%r12,%rax,1),%rdi
  mov    %rax,0x50(%rsp)
  lea    -0x10(%rcx),%rax
  lea    0x0(%rbp,%rax,1),%rsi
  mov    %rdi,0x20(%rsp)
  mov    $0x10,%edi
  mov    %rsi,0x38(%rsp)
  lea    0x8(,%rdx,8),%rsi
  cmovle %rdi,%rsi
  neg    %rdx
  xor    %r8d,%r8d
  mov    %rax,0x60(%rsp)
  shl    $0x3,%rdx
  cmp    $0x2,%ebx
  lea    0x8(%r12),%rax
  lea    0x8(%rdx),%rdi
  lea    (%r12,%rsi,1),%r15
  cmovle %r8,%rdi
  mov    %r15,0x30(%rsp)
  lea    (%r12,%rcx,1),%r8
  lea    (%rdi,%rcx,1),%r9
  lea    0x18(%r12),%rdi
  mov    %r9,0x58(%rsp)
  sub    $0x8,%r9
  cmp    %r10,%rax
  lea    (%r12,%r9,1),%r15
  setae  %r10b
  mov    %rdi,0x8(%rsp)
  mov    %r15,0x28(%rsp)
  lea    0x8(%rbp),%r15
  cmp    %rdi,%r15
  setae  %dil
  or     %edi,%r10d
  cmp    %r11,%rax
  setae  %dil
  cmp    0x8(%rsp),%r13
  setae  0x47(%rsp)
  movzbl 0x47(%rsp),%r11d
  or     %r11d,%edi
  mov    0x38(%rsp),%r11
  and    %r10d,%edi
  cmp    $0x4,%ebx
  setg   %r10b
  and    %r10d,%edi
  cmp    %r11,0x20(%rsp)
  lea    -0x18(%r13,%rcx,1),%r11
  setne  %r10b
  and    %edi,%r10d
  mov    0x20(%rsp),%rdi
  cmp    %r11,%rdi
  setne  %dil
  add    %rbp,%rcx
  and    %r10d,%edi
  cmp    %rcx,%rax
  lea    0x0(%rbp,%r9,1),%r10
  setae  %cl
  cmp    %r10,0x30(%rsp)
  setbe  %r10b
  or     %ecx,%r10d
  lea    0x0(%rbp,%rsi,1),%rcx
  and    %edi,%r10d
  cmp    %rcx,0x28(%rsp)
  setae  %cl
  cmp    %r15,%r8
  setbe  %dil
  or     %edi,%ecx
  and    %r10d,%ecx
  cmp    %r9,%rsi
  setle  %sil
  cmp    %r8,%rax
  setae  %dil
  neg    %rdx
  or     %edi,%esi
  and    %ecx,%esi
  cmp    $0x2,%ebx
  mov    $0x8,%ecx
  cmovle %rcx,%rdx
  add    %r13,%rdx
  cmp    %rdx,0x28(%rsp)
  setae  %dl
  cmp    %r8,%r13
  setae  %cl
  or     %ecx,%edx
  test   %dl,%sil
  je     L188
  mov    0x58(%rsp),%rdx
  mov    0x50(%rsp),%rcx
  lea    -0x10(%r13,%rdx,1),%rdx
  cmp    %rdx,0x30(%rsp)
  setbe  %dl
  add    %r13,%rcx
  cmp    %rcx,%rax
  setae  %cl
  or     %dl,%cl
  je     L188
  cmp    $0x2,%ebx
  mov    $0x1,%r10d
  mov    %r11,%rsi
  mov    %r13,%rdx
  mov    0x60(%rsp),%r8
  mov    0x38(%rsp),%rdi
  mov    %r15,%rcx
  mov    %rax,%r9
  cmovg  0x14(%rsp),%r10d
  add    %r12,%r8
  mov    %r10d,%r11d
  shr    %r11d
  sub    $0x1,%r11d
  shl    $0x4,%r11
  add    0x68(%rsp),%r11
  cs nopw 0x0(%rax,%rax,1)
L161:
  movupd (%rdi),%xmm0
  movupd (%rdx),%xmm1
  add    $0x10,%rdx
  sub    $0x10,%rdi
  movupd (%rcx),%xmm5
  sub    $0x10,%rsi
  add    $0x10,%rcx
  add    $0x10,%r9
  shufpd $0x1,%xmm0,%xmm0
  mulpd  %xmm0,%xmm1
  movupd 0x10(%rsi),%xmm0
  sub    $0x10,%r8
  shufpd $0x1,%xmm0,%xmm0
  mulpd  %xmm5,%xmm0
  addpd  %xmm1,%xmm0
  movups %xmm0,-0x10(%r9)
  movupd -0x10(%rdx),%xmm0
  movupd -0x10(%rcx),%xmm6
  movupd 0x10(%rsi),%xmm1
  movupd 0x10(%rdi),%xmm2
  mulpd  %xmm6,%xmm0
  shufpd $0x1,%xmm1,%xmm1
  shufpd $0x1,%xmm2,%xmm2
  mulpd  %xmm2,%xmm1
  subpd  %xmm1,%xmm0
  shufpd $0x1,%xmm0,%xmm0
  movups %xmm0,0x10(%r8)
  cmp    %r11,%rdx
  jne    L161
  mov    %r10d,%esi
  or     $0x1,%esi
  and    $0x1,%r10d
  je     L65
  mov    %ebx,%ecx
  movslq %esi,%r9
  sub    %esi,%ecx
  lea    0x0(,%r9,8),%rdx
  movslq %ecx,%rcx
  lea    -0x8(%r13,%rdx,1),%r8
  add    %rbp,%rdx
  lea    0x0(,%rcx,8),%rdi
  movsd  (%r8),%xmm0
  lea    0x0(%rbp,%rdi,1),%rsi
  lea    -0x8(%r13,%rdi,1),%rdi
  mulsd  (%rsi),%xmm0
  movsd  (%rdi),%xmm1
  mulsd  (%rdx),%xmm1
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%r12,%r9,8)
  movsd  (%r8),%xmm0
  movsd  (%rdi),%xmm1
  mulsd  (%rdx),%xmm0
  mulsd  (%rsi),%xmm1
  subsd  %xmm1,%xmm0
  movsd  %xmm0,(%r12,%rcx,8)
L65:
  mov    0x40(%rsp),%edx
  test   %edx,%edx
  je     L90
L32:
  mov    0x18(%rsp),%rsi
  xor    %r10d,%r10d
  lea    0x0(,%rsi,8),%r8
  mov    0x14(%rsp),%esi
  lea    -0x8(%r8),%r9
  lea    -0x10(%r8),%rcx
  lea    0x8(,%rsi,8),%rdi
  neg    %rsi
  cmp    $0x2,%ebx
  lea    0x8(,%rsi,8),%rsi
  lea    (%r12,%rcx,1),%rdx
  cmovle %r10,%rsi
  mov    $0x10,%r10d
  lea    0x0(%rbp,%r8,1),%r11
  add    %r9,%rsi
  cmp    $0x2,%ebx
  cmovle %r10,%rdi
  cmp    0x48(%rsp),%rax
  setae  %r10b
  cmp    0x8(%rsp),%r15
  setae  %r13b
  or     %r10d,%r13d
  cmp    $0x4,%ebx
  setg   %r10b
  add    %rbp,%r9
  and    %r13d,%r10d
  cmp    %r9,%rdx
  setne  %r9b
  and    %r9d,%r10d
  cmp    %rdi,%rsi
  setge  %r9b
  cmp    %r11,%r15
  setae  %r13b
  or     %r13d,%r9d
  lea    0x0(%rbp,%rsi,1),%r13
  and    %r10d,%r9d
  lea    (%r12,%rdi,1),%r10
  cmp    %r10,%r13
  setae  %r10b
  cmp    %r11,%rax
  setae  %r11b
  or     %r11d,%r10d
  test   %r10b,%r9b
  je     L144
  add    %rbp,%rdi
  add    %r12,%rsi
  cmp    %rsi,%rdi
  setbe  %sil
  add    %r12,%r8
  cmp    %r8,%r15
  setae  %dil
  or     %dil,%sil
  je     L144
  cmp    $0x2,%ebx
  mov    $0x1,%r8d
  cmovg  0x14(%rsp),%r8d
  mov    %r15,%rsi
  add    %rbp,%rcx
  mov    %r8d,%edi
  shr    %edi
  sub    $0x1,%edi
  shl    $0x4,%rdi
  add    0x8(%rsp),%rdi
  nop
L202:
  movupd (%rdx),%xmm0
  movupd (%rax),%xmm5
  add    $0x10,%rax
  sub    $0x10,%rdx
  add    $0x10,%rsi
  sub    $0x10,%rcx
  shufpd $0x1,%xmm0,%xmm0
  addpd  %xmm5,%xmm0
  movups %xmm0,-0x10(%rsi)
  movupd 0x10(%rdx),%xmm1
  movupd -0x10(%rax),%xmm0
  shufpd $0x1,%xmm1,%xmm1
  subpd  %xmm1,%xmm0
  shufpd $0x1,%xmm0,%xmm0
  movups %xmm0,0x10(%rcx)
  cmp    %rdi,%rax
  jne    L202
  mov    %r8d,%eax
  or     $0x1,%eax
  and    $0x1,%r8d
  je     L106
  sub    %eax,%ebx
  movslq %eax,%rcx
  movslq %ebx,%rbx
  lea    (%r12,%rcx,8),%rdx
  lea    (%r12,%rbx,8),%rax
  movsd  (%rdx),%xmm0
  addsd  (%rax),%xmm0
  movsd  %xmm0,0x0(%rbp,%rcx,8)
  movsd  (%rdx),%xmm0
  subsd  (%rax),%xmm0
  movsd  %xmm0,0x0(%rbp,%rbx,8)
L106:
  movsd  0x0(%rbp),%xmm0
  addsd  %xmm0,%xmm0
  movsd  %xmm0,0x0(%rbp)
  add    $0x78,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
  nopl   0x0(%rax,%rax,1)
L120:
  mov    %r12,%rdx
  mov    %rbp,%rsi
  mov    %ebx,%edi
  call   <rfftb@plt>
  movslq %ebx,%rax
  mov    %rax,0x18(%rsp)
  cmp    $0x2,%ebx
  jg     L77
  jmp    L106
L90:
  movslq %r14d,%rdx
  shl    $0x3,%rdx
  lea    0x0(%rbp,%rdx,1),%rcx
  movsd  (%rcx),%xmm0
  addsd  %xmm0,%xmm0
  mulsd  -0x8(%r13,%rdx,1),%xmm0
  movsd  %xmm0,(%rcx)
  jmp    L32
L168:
  movslq %r14d,%rax
  shl    $0x3,%rax
  lea    0x0(%rbp,%rax,1),%rdx
  movsd  (%rdx),%xmm0
  addsd  %xmm0,%xmm0
  mulsd  -0x8(%r13,%rax,1),%xmm0
  movsd  %xmm0,(%rdx)
  jmp    L106
  nopl   0x0(%rax,%rax,1)
L144:
  mov    0x18(%rsp),%rax
  lea    -0x8(,%rax,8),%rdx
  mov    $0x1,%eax
  nopw   0x0(%rax,%rax,1)
L132:
  movsd  (%r12,%rax,8),%xmm0
  addsd  (%r12,%rdx,1),%xmm0
  movsd  %xmm0,0x0(%rbp,%rax,8)
  movsd  (%r12,%rax,8),%xmm0
  add    $0x1,%rax
  subsd  (%r12,%rdx,1),%xmm0
  movsd  %xmm0,0x0(%rbp,%rdx,1)
  sub    $0x8,%rdx
  cmp    %eax,%r14d
  jg     L132
  jmp    L106
  xchg   %ax,%ax
L188:
  mov    0x18(%rsp),%rsi
  mov    $0x1,%edx
  lea    -0x8(,%rsi,8),%rcx
  nopw   0x0(%rax,%rax,1)
L68:
  movsd  -0x8(%r13,%rdx,8),%xmm0
  movsd  -0x8(%r13,%rcx,1),%xmm1
  mulsd  0x0(%rbp,%rcx,1),%xmm0
  mulsd  0x0(%rbp,%rdx,8),%xmm1
  addsd  %xmm1,%xmm0
  movsd  %xmm0,(%r12,%rdx,8)
  movsd  -0x8(%r13,%rdx,8),%xmm0
  movsd  -0x8(%r13,%rcx,1),%xmm1
  mulsd  0x0(%rbp,%rdx,8),%xmm0
  add    $0x1,%rdx
  mulsd  0x0(%rbp,%rcx,1),%xmm1
  subsd  %xmm1,%xmm0
  movsd  %xmm0,(%r12,%rcx,1)
  sub    $0x8,%rcx
  cmp    %edx,%r14d
  jg     L68
  jmp    L65
```

assistant: ```c
void cosqb1(int n, double x[], double w[], double xh[]) {
  int modn, i, k;
  int kc, ns2;
  double xim1;
  ns2 = (n + 1) / 2;
  for (i = 2; i < n; i += 2) {
    xim1 = x[i - 1] + x[i];
    x[i] -= x[i - 1];
    x[i - 1] = xim1;
  }
  x[0] += x[0];
  modn = n % 2;
  if (modn == 0)
    x[n - 1] += x[n - 1];
  rfftb(n, x, xh);
  for (k = 1; k < ns2; k++) {
    kc = n - k;
    xh[k] = w[k - 1] * x[kc] + w[kc - 1] * x[k];
    xh[kc] = w[k - 1] * x[k] - w[kc - 1] * x[kc];
  }
  if (modn == 0)
    x[ns2] = w[ns2 - 1] * (x[ns2] + x[ns2]);
  for (k = 1; k < ns2; k++) {
    kc = n - k;
    x[k] = xh[k] + xh[kc];
    x[kc] = xh[k] - xh[kc];
  }
  x[0] += x[0];
}
```