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M1.3/M1.4 Map: Map fails to pack RLOC'd carry logic in RPMs (Relationally Placed Macros) with LOC'd DFFs.


Record #2280

Product Family:  Software

Product Line:  Merged Core

Problem Title:
M1.3/M1.4 Map:  Map fails to pack RLOC'd carry logic in RPMs
(Relationally Placed Macros) with LOC'd DFFs.



Problem Description:
Keywords:  map, floorplan, rloc, loc, rpm, rloc_origin, merge

Urgency:  standard

General Description:  Map fails to pack RLOC'd carry logic
(carry logic constrained using RLOC constraints) and LOC'd
DFFs into the same COMPs (CLBs or IOBs).   Valid constraints
in the .UCF may direct both carry logic and DFFs into the same
locations, but MAP does not merge them.

Typically the RLOC'd carry logic is part of an RPM
(Relationally Placed Macro).  The RPM may or may not have an
RLOC_ORIGIN property attached to it by the user.


Solution 1:


This problem may be seen when converting a floorplanned
XACTstep 5.2.x/6.x design to M1.  Map is not capable of
packing logic with valid, overlapping RLOCs and LOCs together,
resulting in the error described above.

WORKAROUND for designs where the carry logic RPM has an
RLOC_ORIGIN attached to it by the user:
------------------------------------------------------------
When converting these designs from XACT to M1, CSTCONV can be
used to translate RLOC origins into hard LOC (location)
constraints within the output .XTF file. The new .xtf and .ucf
files produced by CSTCONV can then be used in the M1 flow.

NOTE:  To perform this translation, CSTCONV requires both a
source .XTF and .CST file (XACT constraints file) for the
design.


Reference #:  10571




End of Record #2280

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