Commit Graph

11 Commits

Author SHA1 Message Date
Tim Edwards 83dce151d8 Made a correction to the last commit. The "FlattenUnmatched()"
routine does not have an exact equivalent in PrematchLists() and
needs to be run beforehand.  This fix keeps FlattenUnmatched()
from being run on all cells at the beginning and restricts it
to being run on the contents of individual cells during matching,
after checking if either of the cells is a black-box.  Avoiding
flattening contents of one side when the other is a black-box
(or simply doesn't contain any subcircuits or devices) prevents
unnecessary flattening of cells that will never get compared.
2021-12-17 20:31:41 -05:00
Kamyar Mohajerani 879711def3 revert removal of superfluous 'extern'
.. for functions based on review comments
2021-11-17 11:53:04 -05:00
Kamyar Mohajerani b5c70decbd fix wrong 'hash' being linked in + C99 compat
This fixes crash on macos due to wrong hash() being linked in.
It also makes sure that proper function defs are declared and available
(as required by C99) to make compile possible in newer compilers (e.g.
Apple clang) and to some extend prevent similar linkage issues happening
again.
2021-11-16 20:06:15 -05:00
Tim Edwards e9da037001 Removed the code for fast symmetry breaking, as it has been found
to generate incorrect results on occasion.  The method to parallelize
cells with the same no-connect pins should avoid the worst-case
symmetry breaking that was previously plaguing the LVS of large
standard-cell layouts.
2021-03-01 16:55:07 -05:00
Tim Edwards 5e99fd5ef9 Found a counterexample which shows that the fast symmetry breaking
introduced in revision 150 can result in an incorrect result
reporting a bad match where the match is actually good (as proven
by running the full symmetry breaking on the same netlist).
Because the fast symmetry breaking is orders of magnitude faster
for large circuits, and because the false positive result appears
to be rare, I have introduced a command "symmetry" to switch
methods between fast and full.  So fast symmetry breaking can be
run unless the result fails on symmetry breaking, in which case
the method can be switched to full to see if the problem is a
false positive or not.  This is not an ideal solution, and some
investigation is needed to determine if there is a way to apply
fast symmetry breaking without encountering a false positive
error.
2020-10-08 09:43:25 -04:00
Tim Edwards 9a1e295367 Based on code from John Wood, added command "netgen::format <col1_width>
<col2_width>" to set the output format width, to avoid the fixed column
widths of 41 characters which can truncate long strings in the output
such as deep cell hierarchies.  This command can be placed in the setup
script to widen the output columns to accomodate the result (to-do:
provide an "auto" mode to automatically determine the best width).
2020-02-10 09:11:34 -05:00
Tim Edwards 2cdf3c450f Extended the series/parallel merging setup commands to include
the possibility that a device (e.g., resistor or capacitor) may
not be a semiconductor device (in other words, a parasitic or
ideal device), and therefore uses "value" but not width and
length, and therefore "value" is a critical property to merge
both in series and parallel.  Corrected the series/parallel
network optimization to prevent it from setting both M and S
records > 1 on the same device (which is ambiguous).  To try
to get number of devices to match, where there are both series
and parallel devices, they will be merged across the critical
property early (before property matching).
2018-11-18 13:04:57 -05:00
Tim Edwards 8deccaad9c Fixed a bug in the combine routine that causes a segfault; added
preliminary support for a Tcl list output format.
2017-01-07 06:56:51 -05:00
Tim Edwards 777498b30e Completed the implementation of serial/parallel device network
matching.
2016-12-12 11:32:07 -05:00
Tim Edwards 9148edde69 Implemented command option 'ignore shorted', same syntax as
'ignore class', but removes instances of the specified class whose
pins are shorted together.  Currently requires that all pins must
be shorted together.
2016-10-18 14:17:57 -04:00
Tim Edwards d5e9f81cb0 Initial commit at Mon May 18 09:27:46 EDT 2015 by tim on stravinsky 2015-05-18 09:27:46 -04:00