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

```asm
<pixel_convert_8u_yuv420p_to_8u_rgb>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  sub    $0x18,%rsp
  mov    %rdi,-0x78(%rbp)
  mov    %esi,-0x7c(%rbp)
  mov    %edx,-0x80(%rbp)
  mov    %ecx,-0x84(%rbp)
  mov    %r8,-0x90(%rbp)
  mov    %r9d,-0x88(%rbp)
  mov    -0x84(%rbp),%eax
  imul   -0x88(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x90(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x40(%rbp)
  mov    -0x84(%rbp),%eax
  imul   -0x88(%rbp),%eax
  lea    0x3(%rax),%edx
  test   %eax,%eax
  cmovs  %edx,%eax
  sar    $0x2,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x40(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x38(%rbp)
  movl   $0x0,-0x64(%rbp)
  jmp    L228
L87:
  mov    -0x64(%rbp),%eax
  imul   -0x88(%rbp),%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x90(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x30(%rbp)
  mov    -0x64(%rbp),%eax
  imul   -0x88(%rbp),%eax
  add    %eax,%eax
  movslq %eax,%rdx
  mov    -0x88(%rbp),%eax
  cltq
  add    %rdx,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x90(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x28(%rbp)
  mov    -0x64(%rbp),%eax
  imul   -0x88(%rbp),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x40(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x20(%rbp)
  mov    -0x64(%rbp),%eax
  imul   -0x88(%rbp),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x38(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x18(%rbp)
  mov    -0x64(%rbp),%eax
  imul   -0x7c(%rbp),%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x78(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x10(%rbp)
  mov    -0x64(%rbp),%eax
  imul   -0x7c(%rbp),%eax
  add    %eax,%eax
  movslq %eax,%rdx
  mov    -0x7c(%rbp),%eax
  cltq
  add    %rdx,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x78(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,-0x8(%rbp)
  movl   $0x0,-0x60(%rbp)
  jmp    L155
L173:
  mov    -0x60(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x20(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  add    $0xffffff80,%eax
  imul   $0x1c6,%eax,%eax
  sar    $0x8,%eax
  mov    %eax,-0x5c(%rbp)
  mov    -0x60(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  add    $0xffffff80,%eax
  imul   $0x167,%eax,%eax
  sar    $0x8,%eax
  mov    %eax,-0x58(%rbp)
  mov    -0x60(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x18(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  add    $0xffffff80,%eax
  imul   $0xb7,%eax,%edx
  mov    -0x60(%rbp),%eax
  cltq
  lea    0x0(,%rax,4),%rcx
  mov    -0x20(%rbp),%rax
  add    %rcx,%rax
  mov    (%rax),%eax
  add    $0xffffff80,%eax
  imul   $0x58,%eax,%eax
  add    %edx,%eax
  sar    $0x8,%eax
  mov    %eax,-0x54(%rbp)
  mov    -0x60(%rbp),%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x50(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x58(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x4c(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x5c(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x48(%rbp)
  mov    -0x50(%rbp),%eax
  sub    -0x54(%rbp),%eax
  mov    %eax,-0x44(%rbp)
  cmpl   $0x0,-0x4c(%rbp)
  js     L46
  mov    -0x4c(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L180
L46:
  mov    $0x0,%edx
L180:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x44(%rbp)
  js     L32
  mov    -0x44(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L104
L32:
  mov    $0x0,%edx
L104:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x48(%rbp)
  js     L71
  mov    -0x48(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L31
L71:
  mov    $0x0,%edx
L31:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x2,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  mov    -0x60(%rbp),%eax
  add    %eax,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x30(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x50(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x58(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x4c(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x5c(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x48(%rbp)
  mov    -0x50(%rbp),%eax
  sub    -0x54(%rbp),%eax
  mov    %eax,-0x44(%rbp)
  cmpl   $0x0,-0x4c(%rbp)
  js     L244
  mov    -0x4c(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L203
L244:
  mov    $0x0,%edx
L203:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x44(%rbp)
  js     L82
  mov    -0x44(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L4
L82:
  mov    $0x0,%edx
L4:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x4,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x48(%rbp)
  js     L152
  mov    -0x48(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L59
L152:
  mov    $0x0,%edx
L59:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x5,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x10(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  mov    -0x60(%rbp),%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x50(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x58(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x4c(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x5c(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x48(%rbp)
  mov    -0x50(%rbp),%eax
  sub    -0x54(%rbp),%eax
  mov    %eax,-0x44(%rbp)
  cmpl   $0x0,-0x4c(%rbp)
  js     L53
  mov    -0x4c(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L179
L53:
  mov    $0x0,%edx
L179:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x44(%rbp)
  js     L159
  mov    -0x44(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L219
L159:
  mov    $0x0,%edx
L219:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x48(%rbp)
  js     L198
  mov    -0x48(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L113
L198:
  mov    $0x0,%edx
L113:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x2,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  mov    -0x60(%rbp),%eax
  add    %eax,%eax
  cltq
  add    $0x1,%rax
  lea    0x0(,%rax,4),%rdx
  mov    -0x28(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,-0x50(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x58(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x4c(%rbp)
  mov    -0x50(%rbp),%edx
  mov    -0x5c(%rbp),%eax
  add    %edx,%eax
  mov    %eax,-0x48(%rbp)
  mov    -0x50(%rbp),%eax
  sub    -0x54(%rbp),%eax
  mov    %eax,-0x44(%rbp)
  cmpl   $0x0,-0x4c(%rbp)
  js     L209
  mov    -0x4c(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L184
L209:
  mov    $0x0,%edx
L184:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x3,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x44(%rbp)
  js     L119
  mov    -0x44(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L190
L119:
  mov    $0x0,%edx
L190:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x4,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  cmpl   $0x0,-0x48(%rbp)
  js     L124
  mov    -0x48(%rbp),%eax
  mov    $0xff,%edx
  cmp    %edx,%eax
  cmovle %eax,%edx
  jmp    L258
L124:
  mov    $0x0,%edx
L258:
  mov    -0x60(%rbp),%ecx
  mov    %ecx,%eax
  add    %eax,%eax
  add    %ecx,%eax
  add    %eax,%eax
  cltq
  add    $0x5,%rax
  lea    0x0(,%rax,4),%rcx
  mov    -0x8(%rbp),%rax
  add    %rcx,%rax
  mov    %edx,(%rax)
  addl   $0x1,-0x60(%rbp)
L155:
  mov    -0x80(%rbp),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  cmp    %eax,-0x60(%rbp)
  jl     L173
  addl   $0x1,-0x64(%rbp)
L228:
  mov    -0x84(%rbp),%eax
  mov    %eax,%edx
  shr    $0x1f,%edx
  add    %edx,%eax
  sar    %eax
  cmp    %eax,-0x64(%rbp)
  jl     L87
  mov    $0x0,%eax
  leave
  ret
```

assistant: ```c
int pixel_convert_8u_yuv420p_to_8u_rgb(uint8_t *dest, int dstride, int dwidth, int dheight, const uint8_t *src, int sstride) {
  const uint8_t *uplane = src + dheight * sstride;
  const uint8_t *vplane = uplane + dheight * sstride / 4;
  for (int i = 0; i < dheight / 2; i++) {
    const uint8_t *yrow1 = src + i * 2 * sstride;
    const uint8_t *yrow2 = src + i * 2 * sstride + sstride;
    const uint8_t *urow = uplane + i * sstride / 2;
    const uint8_t *vrow = vplane + i * sstride / 2;
    uint8_t *rgb1 = dest + i * 2 * dstride;
    uint8_t *rgb2 = dest + i * 2 * dstride + dstride;
    for (int j = 0; j < dwidth / 2; j++) {
      int cb = ((urow[j] - 128) * 454) >> 8;
      int cr = ((vrow[j] - 128) * 359) >> 8;
      int cg = ((vrow[j] - 128) * 183 + (urow[j] - 128) * 88) >> 8;
      int r, g, b, yp;
      yp = yrow1[j * 2];
      r = yp + cr;
      b = yp + cb;
      g = yp - cg;
      rgb1[j * 6 + 0] = ((0) > (((255) < (r) ? (255) : (r))) ? (0) : (((255) < (r) ? (255) : (r))));
      rgb1[j * 6 + 1] = ((0) > (((255) < (g) ? (255) : (g))) ? (0) : (((255) < (g) ? (255) : (g))));
      rgb1[j * 6 + 2] = ((0) > (((255) < (b) ? (255) : (b))) ? (0) : (((255) < (b) ? (255) : (b))));
      yp = yrow1[j * 2 + 1];
      r = yp + cr;
      b = yp + cb;
      g = yp - cg;
      rgb1[j * 6 + 3] = ((0) > (((255) < (r) ? (255) : (r))) ? (0) : (((255) < (r) ? (255) : (r))));
      rgb1[j * 6 + 4] = ((0) > (((255) < (g) ? (255) : (g))) ? (0) : (((255) < (g) ? (255) : (g))));
      rgb1[j * 6 + 5] = ((0) > (((255) < (b) ? (255) : (b))) ? (0) : (((255) < (b) ? (255) : (b))));
      yp = yrow2[j * 2];
      r = yp + cr;
      b = yp + cb;
      g = yp - cg;
      rgb2[j * 6 + 0] = ((0) > (((255) < (r) ? (255) : (r))) ? (0) : (((255) < (r) ? (255) : (r))));
      rgb2[j * 6 + 1] = ((0) > (((255) < (g) ? (255) : (g))) ? (0) : (((255) < (g) ? (255) : (g))));
      rgb2[j * 6 + 2] = ((0) > (((255) < (b) ? (255) : (b))) ? (0) : (((255) < (b) ? (255) : (b))));
      yp = yrow2[j * 2 + 1];
      r = yp + cr;
      b = yp + cb;
      g = yp - cg;
      rgb2[j * 6 + 3] = ((0) > (((255) < (r) ? (255) : (r))) ? (0) : (((255) < (r) ? (255) : (r))));
      rgb2[j * 6 + 4] = ((0) > (((255) < (g) ? (255) : (g))) ? (0) : (((255) < (g) ? (255) : (g))));
      rgb2[j * 6 + 5] = ((0) > (((255) < (b) ? (255) : (b))) ? (0) : (((255) < (b) ? (255) : (b))));
    }
  }
  return 0;
}
```