user: 提供的汇编代码用C语言表示会是什么样子:

```asm
<__imlib_SubBlendShapedSpanToRGB>:
  endbr64
  push   %r13
  push   %r12
  push   %rbp
  push   %rbx
  mov    %esi,%ebx
  mov    %rdx,%rax
  mov    %ecx,%edx
  mov    %esi,%ecx
  shr    $0x18,%ecx
  cmp    $0xff,%cl
  jne    L45
  mov    %edx,%ecx
  add    %rdi,%rcx
  test   %edx,%edx
  je     L43
  mov    %esi,%r10d
  shr    $0x10,%r10d
  movzbl %r10b,%r9d
  movzbl %bh,%esi
  movzbl %bl,%r8d
  jmp    L107
L45:
  mov    %ecx,%esi
  test   %edx,%edx
  je     L43
  mov    %ebx,%r8d
  shr    $0x10,%r8d
  movzbl %r8b,%r9d
  imul   %ecx,%r9d
  mov    %r9d,%r10d
  shr    $0x8,%r10d
  lea    0x80(%r9,%r10,1),%r11d
  shr    $0x8,%r11d
  movzbl %bh,%ebp
  mov    %ebp,%r9d
  imul   %ecx,%r9d
  mov    %r9d,%r10d
  shr    $0x8,%r10d
  lea    0x80(%r9,%r10,1),%r10d
  shr    $0x8,%r10d
  movzbl %bl,%r9d
  imul   %r9d,%ecx
  mov    %ecx,%r9d
  shr    $0x8,%r9d
  lea    0x80(%rcx,%r9,1),%r9d
  shr    $0x8,%r9d
  mov    %edx,%ecx
  add    %rdi,%rcx
  movzbl %sil,%esi
  movzbl %r8b,%r8d
  movzbl %bl,%ebx
  jmp    L90
L75:
  movzbl %dl,%edx
  imul   %esi,%edx
  sub    $0xffffff80,%edx
  mov    %edx,%r12d
  shr    $0x8,%r12d
  add    %r12d,%edx
  shr    $0x8,%edx
  mov    %r8d,%r12d
  imul   %edx,%r12d
  mov    %r12d,%r13d
  shr    $0x8,%r13d
  lea    0x80(%r12,%r13,1),%r12d
  shr    $0x8,%r12d
  movzbl 0x2(%rax),%r13d
  sub    %r12d,%r13d
  mov    %r13d,%r12d
  shr    $0x8,%r12d
  not    %r12d
  and    %r13d,%r12d
  mov    %r12b,0x2(%rax)
  mov    %ebp,%r12d
  imul   %edx,%r12d
  mov    %r12d,%r13d
  shr    $0x8,%r13d
  lea    0x80(%r12,%r13,1),%r12d
  shr    $0x8,%r12d
  movzbl 0x1(%rax),%r13d
  sub    %r12d,%r13d
  mov    %r13d,%r12d
  shr    $0x8,%r12d
  not    %r12d
  and    %r13d,%r12d
  mov    %r12b,0x1(%rax)
  imul   %ebx,%edx
  mov    %edx,%r12d
  shr    $0x8,%r12d
  lea    0x80(%rdx,%r12,1),%edx
  shr    $0x8,%edx
  movzbl (%rax),%r12d
  sub    %edx,%r12d
  mov    %r12d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r12d,%edx
  mov    %dl,(%rax)
L83:
  add    $0x1,%rdi
  add    $0x4,%rax
  cmp    %rdi,%rcx
  je     L43
L90:
  movzbl (%rdi),%edx
  test   %dl,%dl
  je     L83
  cmp    $0xff,%dl
  jne    L75
  movzbl 0x2(%rax),%r12d
  sub    %r11d,%r12d
  mov    %r12d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r12d,%edx
  mov    %dl,0x2(%rax)
  movzbl 0x1(%rax),%r12d
  sub    %r10d,%r12d
  mov    %r12d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r12d,%edx
  mov    %dl,0x1(%rax)
  movzbl (%rax),%r12d
  sub    %r9d,%r12d
  mov    %r12d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r12d,%edx
  mov    %dl,(%rax)
  jmp    L83
L39:
  movzbl %dl,%edx
  imul   %r9d,%edx
  mov    %edx,%r11d
  shr    $0x8,%r11d
  lea    0x80(%rdx,%r11,1),%edx
  shr    $0x8,%edx
  movzbl 0x2(%rax),%r11d
  sub    %edx,%r11d
  mov    %r11d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r11d,%edx
  mov    %dl,0x2(%rax)
  movzbl (%rdi),%edx
  imul   %esi,%edx
  mov    %edx,%r11d
  shr    $0x8,%r11d
  lea    0x80(%rdx,%r11,1),%edx
  shr    $0x8,%edx
  movzbl 0x1(%rax),%r11d
  sub    %edx,%r11d
  mov    %r11d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r11d,%edx
  mov    %dl,0x1(%rax)
  movzbl (%rdi),%edx
  imul   %r8d,%edx
  mov    %edx,%r11d
  shr    $0x8,%r11d
  lea    0x80(%rdx,%r11,1),%edx
  shr    $0x8,%edx
  movzbl (%rax),%r11d
  sub    %edx,%r11d
  mov    %r11d,%edx
  shr    $0x8,%edx
  not    %edx
  and    %r11d,%edx
  mov    %dl,(%rax)
L9:
  add    $0x1,%rdi
  add    $0x4,%rax
  cmp    %rcx,%rdi
  je     L43
L107:
  movzbl (%rdi),%edx
  test   %dl,%dl
  je     L9
  cmp    $0xff,%dl
  jne    L39
  movzbl 0x2(%rax),%r11d
  movzbl %r11b,%edx
  sub    %r9d,%edx
  shr    $0x8,%edx
  not    %edx
  sub    %r10d,%r11d
  and    %r11d,%edx
  mov    %dl,0x2(%rax)
  movzbl 0x1(%rax),%r11d
  movzbl %r11b,%edx
  sub    %esi,%edx
  shr    $0x8,%edx
  not    %edx
  sub    %esi,%r11d
  and    %r11d,%edx
  mov    %dl,0x1(%rax)
  movzbl (%rax),%r11d
  movzbl %r11b,%edx
  sub    %r8d,%edx
  shr    $0x8,%edx
  not    %edx
  sub    %ebx,%r11d
  and    %r11d,%edx
  mov    %dl,(%rax)
  jmp    L9
L43:
  pop    %rbx
  pop    %rbp
  pop    %r12
  pop    %r13
  ret
```

assistant: ```c
void __imlib_SubBlendShapedSpanToRGB(unsigned char *src, unsigned int color, unsigned int *dst, int len) {
  if (((unsigned char *)(&color))[3] < 255) {
    while (len--) {
      unsigned int tmp;
      unsigned char a;
      switch (*src) {
      case 0:
        break;
      case 255: {
        tmp = (((unsigned char *)(&color))[2]) * (((unsigned char *)(&color))[3]);
        tmp = (((unsigned char *)(dst))[2]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[2] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(&color))[1]) * (((unsigned char *)(&color))[3]);
        tmp = (((unsigned char *)(dst))[1]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[1] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(&color))[0]) * (((unsigned char *)(&color))[3]);
        tmp = (((unsigned char *)(dst))[0]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[0] = (tmp & (~(tmp >> 8)));
        ;
        ;
        break;
      }
      default: {
        do {
          tmp = ((*src) * (((unsigned char *)(&color))[3])) + 0x80;
          a = (tmp + (tmp >> 8)) >> 8;
        } while (0);
        tmp = (((unsigned char *)(&color))[2]) * (a);
        tmp = (((unsigned char *)(dst))[2]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[2] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(&color))[1]) * (a);
        tmp = (((unsigned char *)(dst))[1]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[1] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(&color))[0]) * (a);
        tmp = (((unsigned char *)(dst))[0]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
        ((unsigned char *)(dst))[0] = (tmp & (~(tmp >> 8)));
        ;
        ;
        break;
      }
      }
      src++;
      dst++;
    }
    return;
  }
  while (len--) {
    unsigned int tmp;
    switch (*src) {
    case 0:
      break;
    case 255: {
      do {
        tmp = (((unsigned char *)(dst))[2]) - (((unsigned char *)(&color))[2]);
        ((unsigned char *)(dst))[2] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(dst))[1]) - (((unsigned char *)(&color))[1]);
        ((unsigned char *)(dst))[1] = (tmp & (~(tmp >> 8)));
        ;
        tmp = (((unsigned char *)(dst))[0]) - (((unsigned char *)(&color))[0]);
        ((unsigned char *)(dst))[0] = (tmp & (~(tmp >> 8)));
        ;
      } while (0);
      break;
    }
    default: {
      tmp = (((unsigned char *)(&color))[2]) * (*src);
      tmp = (((unsigned char *)(dst))[2]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
      ((unsigned char *)(dst))[2] = (tmp & (~(tmp >> 8)));
      ;
      tmp = (((unsigned char *)(&color))[1]) * (*src);
      tmp = (((unsigned char *)(dst))[1]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
      ((unsigned char *)(dst))[1] = (tmp & (~(tmp >> 8)));
      ;
      tmp = (((unsigned char *)(&color))[0]) * (*src);
      tmp = (((unsigned char *)(dst))[0]) - ((tmp + (tmp >> 8) + 0x80) >> 8);
      ((unsigned char *)(dst))[0] = (tmp & (~(tmp >> 8)));
      ;
      ;
      break;
    }
    }
    src++;
    dst++;
  }
}
```