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Chapter 3: Reference
Error Messages
expressions must be reduced to 16 and the complexity of some of the
expressions may have to also be reduced.
Branch expressions that are identical (and simple enough to be
combined by a single combiner resource) share the same combiner
resource. Reusing identical event list equations where possible will
optimize the use of combiner resources (see pa ge 183).
You may find more information in the Branch expression is too
complex (see page 171) error message help for the 800 and 1250 Mb/s
modes.
Combiner resource allocation guidelines:
Labels that span multiple pod pairs (split labels) increases the number of
required combiner resources as compared with labels that are entirely
contained within a single pod pair.
Whenever possible try to arrange the probing such that labels do not span
pod pairs. This is the single most effective way to reduce the number of
required combiner resources.
NOTE: For labels that do span pod pairs the complexity can b e reduced to
the same as that of the non-split label case if all bits in the label on all but
one pod pair can be set to Xs in the event list expression for the
measurement.
For example, if label ADDR has it's 16 most significant bits on pod A3 and
16 least significant bits on pod A2 (spanning pod pai rs A4/A3 and A2/A1),
the complexity of the compiled expression will be reduced if all 16 most
significant bits or all 16 least significant bits are set to Xs in the pattern
event.
Event lists with up to 4 unique patt ern events can be combined in any
combination of ANDs and ORs by a single combiner resource if all of the
pattern labels are non-split and contained on t he same pod pair.
Combining more than 4 labels o n the same pod pair will require anothe r
combiner resource.
Non-split label pattern events from different pod pairs that are ORed
together require an additional combiner resource for each additional pod
pair included in the event list. (ANDing on non-split patterns from
different pod pairs does not increase the required number of combiner