value range propagation for _bitwise_ OR
schveiguy at yahoo.com
Fri Apr 16 21:43:41 PDT 2010
Andrei Alexandrescu Wrote:
> Looks great, thanks Jerome!
> Now, how about that case in which some or all of the ranges involved
> include negative values?
I solved already signed values in terms of any valid unsigned solution, see here: http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D&article_id=108869
The maxor with all the unsigned casts is the call to the unsigned maxor. Ditto for minor.
Also, see my one liner for unsigned maxor:
All that is left is to find a quick (possibly one liner?) minor for unsigned. Maybe there's a quicker signed solution, but the complexity is already O(1) * complexity of unsigned.
Also, someone pointed out that Jerome's highbit is equivalent to the x86 bsr instruction (std.instrinsic.bsr).
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