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

```asm
<copyImage2To32>:
  endbr64
  push   %rbp
  mov    %rsp,%rbp
  push   %r14
  push   %r13
  push   %r12
  push   %rbx
  mov    %rdi,-0x68(%rbp)
  mov    %rsi,-0x70(%rbp)
  mov    %edx,-0x74(%rbp)
  mov    %ecx,-0x78(%rbp)
  mov    %r8d,-0x7c(%rbp)
  mov    %r9d,-0x80(%rbp)
  mov    -0x74(%rbp),%eax
  add    %eax,%eax
  add    $0x1f,%eax
  sar    $0x5,%eax
  shl    $0x2,%eax
  cltq
  mov    %rax,-0x38(%rbp)
  mov    -0x80(%rbp),%eax
  cltq
  imul   -0x38(%rbp),%rax
  mov    %rax,%rdx
  mov    -0x7c(%rbp),%eax
  add    %eax,%eax
  sar    $0x5,%eax
  shl    $0x2,%eax
  cltq
  add    %rdx,%rax
  mov    %rax,-0x50(%rbp)
  mov    -0x7c(%rbp),%eax
  not    %eax
  and    $0xf,%eax
  add    %eax,%eax
  cltq
  mov    %rax,-0x30(%rbp)
  mov    -0x74(%rbp),%eax
  shl    $0x5,%eax
  add    $0x1f,%eax
  sar    $0x5,%eax
  shl    $0x2,%eax
  cltq
  mov    %rax,-0x28(%rbp)
  movq   $0x0,-0x48(%rbp)
  mov    0x10(%rbp),%eax
  shl    $0x5,%eax
  sar    $0x5,%eax
  shl    $0x2,%eax
  cltq
  mov    %rax,-0x40(%rbp)
  mov    -0x80(%rbp),%eax
  mov    %eax,-0x54(%rbp)
  jmp    L34
L19:
  mov    -0x68(%rbp),%rdx
  mov    -0x50(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,%r13
  mov    -0x70(%rbp),%rdx
  mov    -0x48(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,%r12
  mov    -0x70(%rbp),%rdx
  mov    -0x40(%rbp),%rax
  add    %rdx,%rax
  mov    %rax,%r14
  mov    -0x30(%rbp),%rax
  mov    %eax,%ebx
  jmp    L45
L20:
  mov    0x0(%r13),%eax
  mov    %ebx,%ecx
  shr    %cl,%eax
  mov    %eax,%eax
  and    $0x3,%eax
  lea    0x0(,%rax,4),%rdx
  mov    0x20(%rbp),%rax
  add    %rdx,%rax
  mov    (%rax),%eax
  mov    %eax,(%r12)
  add    $0x4,%r12
  sub    $0x2,%ebx
  test   %ebx,%ebx
  jns    L45
  mov    $0x1e,%ebx
  add    $0x4,%r13
L45:
  cmp    %r14,%r12
  jb     L20
  mov    -0x38(%rbp),%rax
  add    %rax,-0x50(%rbp)
  mov    -0x28(%rbp),%rax
  add    %rax,-0x48(%rbp)
  mov    -0x28(%rbp),%rax
  add    %rax,-0x40(%rbp)
  addl   $0x1,-0x54(%rbp)
L34:
  mov    -0x54(%rbp),%eax
  cmp    0x18(%rbp),%eax
  jl     L19
  nop
  nop
  pop    %rbx
  pop    %r12
  pop    %r13
  pop    %r14
  pop    %rbp
  ret
```

assistant: ```c
void copyImage2To32(int *fromImageData, int *toImageData, int width, int height, int affectedL, int affectedT, int affectedR, int affectedB, unsigned int *stColors) {
  long scanLine2, firstWord2, firstShift2;
  long scanLine32, firstWord32, lastWord32;
  int line;
  scanLine2 = ((((width) * (2) + 31) >> 5) << 2);
  firstWord2 = scanLine2 * affectedT + ((((affectedL) * (2)) >> 5) << 2);
  firstShift2 = 30 - ((affectedL & 15) * 2);
  scanLine32 = ((((width) * (32) + 31) >> 5) << 2);
  firstWord32 = 0;
  lastWord32 = ((((affectedR) * (32)) >> 5) << 2);
  for (line = affectedT; line < affectedB; line++) {
    register unsigned int *from = (unsigned int *)((long)fromImageData + firstWord2);
    register unsigned int *to = (unsigned int *)((long)toImageData + firstWord32);
    register unsigned int *limit = (unsigned int *)((long)toImageData + lastWord32);
    register int shift = firstShift2;
    while (to < limit) {
      *to = stColors[(*from >> shift) & 3];
      to++;
      shift -= 2;
      if (shift < 0) {
        shift = 30;
        from++;
      }
    }
    firstWord2 += scanLine2;
    firstWord32 += scanLine32;
    lastWord32 += scanLine32;
  }
}
```