Re: Simple Value Range Propagation

[Josef Zlomek <zlomj9am at artax dot karlin dot mff dot cuni dot cz>]

> > > >                           insn-attrtab.c   combine.c
> > > > total time (-O2)          ~ 20 s           ~ 5.5 s
> > > > VRP + current fibheap     0.30 s           0.09 s
> > > > VRP + speedup fibheap     0.27 s           0.07 s
> > > > VRP + normal heap         0.23 s           0.06 s
> > > 
> > Maybe support for other allocator than calloc (for example alloc-pool.c)
> > would help. Allocation of each node is what heap.c does not do so
> > speeding up allocation might help to speed up fibheap.c.
> 
> not really; the measurements I have done for df.c claim
>                 0.03    0.85  384460/405950      fibheap_extract_min
>                 0.02    0.08  384460/405950      fibheap_insert
> 
> while for simple heaps
>                 0.03    0.00  384460/384460      heap_extract_min
>                 0.02    0.00  384460/384460      heap_insert

I guess the time consumed by calloc is not counted in fibnode_new.

> note that there is no allocation done in fibheap_extract_min, so

But deallocation is there...

> improving the allocation in fibheap_insert would not help much (although
> of course it would be better to use xmalloc there instead of xcalloc,
> given that we initialize all fields then anyway).

Not all, we assume that some of them are set to 0 by calloc.

Josef