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

```asm
<effective_transpose>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %rdi,%r15
  mov    %rsi,%r12
  mov    %edx,%r10d
  lea    -0xf(%rdx),%r14d
  test   %r14d,%r14d
  jle    L4
  mov    %edx,%eax
  shl    $0x4,%eax
  mov    %eax,-0xc(%rsp)
  cltq
  shl    $0x2,%rax
  mov    %rax,-0x18(%rsp)
  movslq %edx,%rsi
  shl    $0x2,%rsi
  movl   $0x0,-0x10(%rsp)
  mov    $0x0,%r13d
  lea    0x40(%r12),%rax
  mov    %rax,-0x8(%rsp)
L164:
  mov    %r13d,-0x1c(%rsp)
  lea    (%r15,%r13,4),%rbp
  movslq -0x10(%rsp),%rax
  mov    -0x8(%rsp),%rbx
  lea    (%rbx,%rax,4),%rbx
  mov    $0x0,%r11d
  lea    0x10(%r13),%r9d
L133:
  mov    %rbx,%rcx
  mov    %rbp,%r8
  mov    -0x1c(%rsp),%edi
L109:
  lea    -0x40(%rcx),%rax
  mov    %r8,%rdx
  mov    %edi,-0x20(%rsp)
L46:
  mov    (%rax),%edi
  mov    %edi,(%rdx)
  add    $0x4,%rax
  add    %rsi,%rdx
  cmp    %rcx,%rax
  jne    L46
  mov    -0x20(%rsp),%edi
  add    $0x1,%edi
  add    $0x4,%r8
  add    %rsi,%rcx
  cmp    %r9d,%edi
  jne    L109
  add    -0x18(%rsp),%rbp
  add    $0x40,%rbx
  add    $0x10,%r11
  cmp    %r11d,%r14d
  jg     L133
  add    $0x10,%r13
  mov    -0xc(%rsp),%ebx
  add    %ebx,-0x10(%rsp)
  cmp    %r13d,%r14d
  jg     L164
  lea    -0x10(%r10),%eax
  and    $0xfffffff0,%eax
  lea    0x10(%rax),%edi
L106:
  cmp    %edi,%r10d
  jle    L146
  mov    %edi,%r13d
  imul   %r10d,%r13d
  movslq %edi,%rax
  lea    (%r15,%rax,4),%rbp
  mov    %r10d,%r11d
  shl    $0x4,%r11d
  movslq %r11d,%r11
  shl    $0x2,%r11
  movslq %r10d,%rsi
  shl    $0x2,%rsi
  mov    %edi,%ebx
  lea    0x40(%r12),%r14
  jmp    L2
L4:
  mov    $0x0,%edi
  jmp    L106
L150:
  lea    -0x40(%rcx),%rax
  mov    %r9,%rdx
  mov    %edi,-0x20(%rsp)
L153:
  mov    (%rax),%edi
  mov    %edi,(%rdx)
  add    $0x4,%rax
  add    %rsi,%rdx
  cmp    %rcx,%rax
  jne    L153
  mov    -0x20(%rsp),%edi
  add    $0x10,%r8d
  add    %r11,%r9
  add    $0x40,%rcx
  cmp    %edi,%r8d
  jl     L150
L16:
  add    $0x1,%ebx
  add    %r10d,%r13d
  add    $0x4,%rbp
  cmp    %ebx,%r10d
  je     L146
L2:
  test   %edi,%edi
  jle    L16
  movslq %r13d,%rax
  lea    (%r14,%rax,4),%rcx
  mov    %rbp,%r9
  mov    $0x0,%r8d
  jmp    L150
L146:
  test   %r10d,%r10d
  jle    L59
  mov    %r10d,%eax
  imul   %edi,%eax
  cltq
  lea    (%r15,%rax,4),%rbx
  movslq %r10d,%r8
  shl    $0x2,%r8
  mov    $0x0,%r11d
  mov    $0x0,%r9d
  movslq %edi,%rbp
  lea    -0x1(%r10),%ecx
  sub    %edi,%ecx
  add    %rbp,%rcx
  lea    0x4(%r12),%r13
  jmp    L148
L187:
  movslq %r11d,%rdx
  lea    0x0(%rbp,%rdx,1),%rax
  lea    (%r12,%rax,4),%rax
  add    %rcx,%rdx
  lea    0x0(%r13,%rdx,4),%r14
  mov    %rbx,%rdx
L62:
  mov    (%rax),%esi
  mov    %esi,(%rdx)
  add    $0x4,%rax
  add    %r8,%rdx
  cmp    %r14,%rax
  jne    L62
L141:
  add    $0x1,%r9d
  add    $0x4,%rbx
  add    %r10d,%r11d
  cmp    %r9d,%r10d
  je     L59
L148:
  cmp    %edi,%r10d
  jg     L187
  jmp    L141
L59:
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
```

assistant: ```c
void effective_transpose(int *dst, int *src, int N) {
  int i, j, a, b;
  for (i = 0; i <= N - 16; i += 16)
    for (j = 0; j <= N - 16; j += 16)
      for (a = i; a < i + 16; a++)
        for (b = j; b < j + 16; b++)
          dst[b * N + a] = src[a * N + b];
  int offset = i;
  for (i = offset; i <= N - 1; i++)
    for (j = 0; j < offset; j += 16)
      for (b = j; b < j + 16; b++)
        dst[b * N + i] = src[i * N + b];
  for (i = 0; i <= N - 1; i++)
    for (j = offset; j <= N - 1; j++)
      dst[j * N + i] = src[i * N + j];
}
```