static av_always_inline void fill_rectangle(void *vp, int w, int h, int stride, uint32_t val, int size){
    uint8_t *p= (uint8_t*)vp;
    assert(size==1 || size==4);
    assert(w<=4);

    w      *= size;
    stride *= size;

    assert((((long)vp)&(FFMIN(w, STRIDE_ALIGN)-1)) == 0);
    assert((stride&(w-1))==0);
    if(w==2){
        const uint16_t v= size==4 ? val : val*0x0101;
        *(uint16_t*)(p + 0*stride)= v;
        if(h==1) return;
        *(uint16_t*)(p + 1*stride)= v;
        if(h==2) return;
        *(uint16_t*)(p + 2*stride)= v;
        *(uint16_t*)(p + 3*stride)= v;
    }else if(w==4){
        const uint32_t v= size==4 ? val : val*0x01010101;
        *(uint32_t*)(p + 0*stride)= v;
        if(h==1) return;
        *(uint32_t*)(p + 1*stride)= v;
        if(h==2) return;
        *(uint32_t*)(p + 2*stride)= v;
        *(uint32_t*)(p + 3*stride)= v;
    }else if(w==8){
    //gcc can't optimize 64bit math on x86_32
#ifdef HAVE_FAST_64BIT
        const uint64_t v= val*0x0100000001ULL;
        *(uint64_t*)(p + 0*stride)= v;
        if(h==1) return;
        *(uint64_t*)(p + 1*stride)= v;
        if(h==2) return;
        *(uint64_t*)(p + 2*stride)= v;
        *(uint64_t*)(p + 3*stride)= v;
    }else if(w==16){
        const uint64_t v= val*0x0100000001ULL;
        *(uint64_t*)(p + 0+0*stride)= v;
        *(uint64_t*)(p + 8+0*stride)= v;
        *(uint64_t*)(p + 0+1*stride)= v;
        *(uint64_t*)(p + 8+1*stride)= v;
        if(h==2) return;
        *(uint64_t*)(p + 0+2*stride)= v;
        *(uint64_t*)(p + 8+2*stride)= v;
        *(uint64_t*)(p + 0+3*stride)= v;
        *(uint64_t*)(p + 8+3*stride)= v;
#else
        *(uint32_t*)(p + 0+0*stride)= val;
        *(uint32_t*)(p + 4+0*stride)= val;
        if(h==1) return;
        *(uint32_t*)(p + 0+1*stride)= val;
        *(uint32_t*)(p + 4+1*stride)= val;
        if(h==2) return;
        *(uint32_t*)(p + 0+2*stride)= val;
        *(uint32_t*)(p + 4+2*stride)= val;
        *(uint32_t*)(p + 0+3*stride)= val;
        *(uint32_t*)(p + 4+3*stride)= val;
    }else if(w==16){
        *(uint32_t*)(p + 0+0*stride)= val;
        *(uint32_t*)(p + 4+0*stride)= val;
        *(uint32_t*)(p + 8+0*stride)= val;
        *(uint32_t*)(p +12+0*stride)= val;
        *(uint32_t*)(p + 0+1*stride)= val;
        *(uint32_t*)(p + 4+1*stride)= val;
        *(uint32_t*)(p + 8+1*stride)= val;
        *(uint32_t*)(p +12+1*stride)= val;
        if(h==2) return;
        *(uint32_t*)(p + 0+2*stride)= val;
        *(uint32_t*)(p + 4+2*stride)= val;
        *(uint32_t*)(p + 8+2*stride)= val;
        *(uint32_t*)(p +12+2*stride)= val;
        *(uint32_t*)(p + 0+3*stride)= val;
        *(uint32_t*)(p + 4+3*stride)= val;
        *(uint32_t*)(p + 8+3*stride)= val;
        *(uint32_t*)(p +12+3*stride)= val;
#endif
    }else
        assert(0);
    assert(h==4);
}