Searched hist:"6 dd726a2bf1b800289d90a84d5fcb5ce7b78a8e1" (Results 1 – 2 of 2) sorted by relevance
/openbmc/qemu/util/ |
H A D | range.c | diff 6dd726a2bf1b800289d90a84d5fcb5ce7b78a8e1 Fri Jul 01 06:47:48 CDT 2016 Markus Armbruster <armbru@redhat.com> range: Replace internal representation of Range
Range represents a range as follows. Member @start is the inclusive lower bound, member @end is the exclusive upper bound. Zero @end is special: if @start is also zero, the range is empty, else @end is to be interpreted as 2^64. No other empty ranges may occur.
The range [0,2^64-1] cannot be represented. If you try to create it with range_set_bounds1(), you get the empty range instead. If you try to create it with range_set_bounds() or range_extend(), assertions fail. Before range_set_bounds() existed, the open-coded creation usually got you the empty range instead. Open deathtrap.
Moreover, the code dealing with the janus-faced @end is too clever by half.
Dumb this down to a more pedestrian representation: members @lob and @upb are inclusive lower and upper bounds. The empty range is encoded as @lob = 1, @upb = 0.
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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/openbmc/qemu/include/qemu/ |
H A D | range.h | diff 6dd726a2bf1b800289d90a84d5fcb5ce7b78a8e1 Fri Jul 01 06:47:48 CDT 2016 Markus Armbruster <armbru@redhat.com> range: Replace internal representation of Range
Range represents a range as follows. Member @start is the inclusive lower bound, member @end is the exclusive upper bound. Zero @end is special: if @start is also zero, the range is empty, else @end is to be interpreted as 2^64. No other empty ranges may occur.
The range [0,2^64-1] cannot be represented. If you try to create it with range_set_bounds1(), you get the empty range instead. If you try to create it with range_set_bounds() or range_extend(), assertions fail. Before range_set_bounds() existed, the open-coded creation usually got you the empty range instead. Open deathtrap.
Moreover, the code dealing with the janus-faced @end is too clever by half.
Dumb this down to a more pedestrian representation: members @lob and @upb are inclusive lower and upper bounds. The empty range is encoded as @lob = 1, @upb = 0.
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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