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

```asm
<pixel_satd_wxh>:
  endbr64
  push   %r15
  push   %r14
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  sub    $0x118,%rsp
  mov    %rdi,0x50(%rsp)
  mov    %esi,0x38(%rsp)
  mov    %rdx,0x58(%rsp)
  mov    %ecx,0x3c(%rsp)
  mov    %r8d,0x64(%rsp)
  mov    %fs:0x28,%rax
  mov    %rax,0x108(%rsp)
  xor    %eax,%eax
  test   %r9d,%r9d
  jle    L55
  lea    0x0(,%rsi,4),%eax
  sub    $0x1,%r9d
  movl   $0x0,0x14(%rsp)
  cltq
  and    $0xfffffffc,%r9d
  movl   $0x0,0x60(%rsp)
  shl    $0x2,%rax
  mov    %rax,0x68(%rsp)
  lea    0x0(,%rcx,4),%eax
  cltq
  shl    $0x2,%rax
  mov    %rax,0x70(%rsp)
  lea    0x4(%r9),%eax
  mov    %eax,0x78(%rsp)
  lea    -0x1(%r8),%eax
  shr    $0x2,%eax
  add    $0x1,%eax
  mov    %eax,0x7c(%rsp)
  lea    0xc0(%rsp),%rax
  mov    %rax,0x40(%rsp)
  lea    0x80(%rsp),%rax
  mov    %rax,0x48(%rsp)
  lea    0x90(%rsp),%rax
  mov    %rax,0x18(%rsp)
  nopl   0x0(%rax)
L69:
  mov    0x64(%rsp),%eax
  test   %eax,%eax
  jle    L27
  mov    0x58(%rsp),%rax
  mov    0x50(%rsp),%rdx
  mov    %rax,0x20(%rsp)
  mov    0x7c(%rsp),%eax
  mov    %rdx,0x8(%rsp)
  shl    $0x4,%rax
  add    %rdx,%rax
  mov    %rax,0x28(%rsp)
  lea    0x100(%rsp),%rax
  mov    %rax,0x30(%rsp)
  nopl   (%rax)
L37:
  mov    0x40(%rsp),%rbx
  mov    0x3c(%rsp),%r9d
  mov    $0x4,%esi
  mov    0x20(%rsp),%r8
  mov    0x38(%rsp),%ecx
  mov    0x8(%rsp),%rdx
  mov    %rbx,%rdi
  call   <pixel_sub_wxh@plt>
  mov    0x48(%rsp),%rdi
  mov    0x30(%rsp),%r10
  mov    %rbx,%rsi
  mov    %rdi,%r15
L14:
  mov    (%rsi),%eax
  mov    0x8(%rsi),%edx
  add    $0x10,%rsi
  add    $0x10,%rdi
  mov    -0xc(%rsi),%ecx
  mov    -0x4(%rsi),%r8d
  add    %eax,%ecx
  add    %edx,%r8d
  sub    -0xc(%rsi),%eax
  sub    -0x4(%rsi),%edx
  lea    (%rcx,%r8,1),%r9d
  sub    %r8d,%ecx
  mov    %ecx,-0xc(%rdi)
  mov    %eax,%ecx
  add    %edx,%eax
  sub    %edx,%ecx
  mov    %r9d,-0x10(%rdi)
  mov    %ecx,-0x8(%rdi)
  mov    %eax,-0x4(%rdi)
  cmp    %rsi,%r10
  jne    L14
L48:
  mov    (%r15),%ebp
  mov    0x20(%r15),%r12d
  add    $0x4,%r15
  mov    0xc(%r15),%r13d
  mov    0x2c(%r15),%r14d
  add    %ebp,%r13d
  add    %r12d,%r14d
  sub    0xc(%r15),%ebp
  sub    0x2c(%r15),%r12d
  lea    0x0(%r13,%r14,1),%edi
  call   <abs@plt>
  mov    %r13d,%edi
  sub    %r14d,%edi
  mov    %rax,%rbx
  call   <abs@plt>
  mov    %ebp,%edi
  sub    %r12d,%edi
  add    %rax,%rbx
  call   <abs@plt>
  lea    0x0(%rbp,%r12,1),%edi
  add    %rax,%rbx
  call   <abs@plt>
  add    %rax,%rbx
  add    %ebx,0x14(%rsp)
  cmp    %r15,0x18(%rsp)
  jne    L48
  addq   $0x10,0x8(%rsp)
  mov    0x8(%rsp),%rax
  addq   $0x10,0x20(%rsp)
  cmp    0x28(%rsp),%rax
  jne    L37
L27:
  mov    0x68(%rsp),%rdx
  addl   $0x4,0x60(%rsp)
  add    %rdx,0x50(%rsp)
  mov    0x60(%rsp),%eax
  mov    0x70(%rsp),%rdx
  add    %rdx,0x58(%rsp)
  cmp    0x78(%rsp),%eax
  jne    L69
  mov    0x14(%rsp),%edx
  mov    %edx,%eax
  shr    $0x1f,%eax
  add    %edx,%eax
  sar    %eax
L71:
  mov    0x108(%rsp),%rdx
  sub    %fs:0x28,%rdx
  jne    L50
  add    $0x118,%rsp
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %r15
  ret
L55:
  xor    %eax,%eax
  jmp    L71
L50:
  call   <__stack_chk_fail@plt>
```

assistant: ```c
int pixel_satd_wxh(uint8_t *pix1, int i_pix1, uint8_t *pix2, int i_pix2, int i_width, int i_height) {
  int16_t tmp[4][4];
  int16_t diff[4][4];
  int x, y;
  int i_satd = 0;
  for (y = 0; y < i_height; y += 4) {
    for (x = 0; x < i_width; x += 4) {
      int d;
      pixel_sub_wxh((int16_t *)diff, 4, &pix1[x], i_pix1, &pix2[x], i_pix2);
      for (d = 0; d < 4; d++) {
        int s01, s23;
        int d01, d23;
        s01 = diff[d][0] + diff[d][1];
        s23 = diff[d][2] + diff[d][3];
        d01 = diff[d][0] - diff[d][1];
        d23 = diff[d][2] - diff[d][3];
        tmp[d][0] = s01 + s23;
        tmp[d][1] = s01 - s23;
        tmp[d][2] = d01 - d23;
        tmp[d][3] = d01 + d23;
      }
      for (d = 0; d < 4; d++) {
        int s01, s23;
        int d01, d23;
        s01 = tmp[0][d] + tmp[1][d];
        s23 = tmp[2][d] + tmp[3][d];
        d01 = tmp[0][d] - tmp[1][d];
        d23 = tmp[2][d] - tmp[3][d];
        i_satd += abs(s01 + s23) + abs(s01 - s23) + abs(d01 - d23) + abs(d01 + d23);
      }
    }
    pix1 += 4 * i_pix1;
    pix2 += 4 * i_pix2;
  }
  return i_satd / 2;
}
```