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.
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.
Changed line breaks in log and stdout to better differentiate subcircuits.
Added merged series device counts and differentiated from parallel merged device counts.
Added file number to disconnected net, merged count messages.
Changed black box errors to show file numbers instead of hard coded values.
Final error cell list changed from all on one line to one per line.
Removed redundant display in black box warning.
print statement, and clarified the messages about non-matching
circuits at the end, all of them suggestions made by Mitch
Bailey (see issue #34 on github).
saying that pins were mismatched when pin matching was never run
accidentally resulted in pin matching not being applied to black-box
entries. This has been corrected.
The algorithm is to run without exhaustive subdivision until the
last step because this is much faster. The final iteration must
be run with exhaustive subdivision on, or else it is possible to
have cells with swapped pins matching. The routines that resolve
automorphisms were setting exhaustive subdivision for the final
iteration. But simple "run converge" and "run resolve" were not.
class during setup, for the purpose of generating some derived
value that is used for merging and sorting, such as area = l*w.
Note that this likely needs adjusting so that the expression is
evaluated but not replaced for the purpose of sorting, since the
values to the parameter may change after parallel and series
merging.
cause inexplicable output in case of a property error by showing a
netlist topography error instead of a property error (but the output
shows that the netlists match, and there is no reporting of any
property errors). This error was discovered while implementing a
better sorting method for parallel combination. The improved method
sorts on two properties rather than one, and so should not fall into
the error where, say, devices are sorted on W but have different L
for a device like a capacitor where no "critical" property is
specified (and other similar cases, although that is a common one).
pins for enabling parallel combinations, which could cause a crash.
Added a "-force" option to "equate pins" to allow pins to be matched
even on subcircuits that did not correctly match; this was done in
conjuction with an extra option to the "lvs" command "-noflatten="
to pass a list of cellname to not be flattened even if they do not
match. This is generally discouraged, as it prevents netgen from
resolving differences between layout and schematic hierarchy, but it
can be useful for checking that the hierarchy above a certain cell
is correct, given that if a subcell is really unmatched, then its
errors will keep propagating up the top level, making additional
errors hard to diagnose.
can be turned on or off from the setup using "property parallel open"
to allow parallelizing devices with no-connect pins vs. "property
parallel connected" to only allow parallelizing of devices with all
pins connected.
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.
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.
with the file number, so that it can get confused between libraries.
Also made a fix to coerce one cell class to be forced to be the
same in both circuits under some circumstances.
the top level circuits to be declared matching with no errors even
though the pins do not match. "proxy pins" are fine for subcells
to detect cases where one subcell has an unused pin and the matching
subcell does not declare it, but that should not be allowed on the
top level, as it cannot be known whether the pin is unused or not.
are matched on circuits that have no elements. This condition
does not necessarily indicate an error, and matching pins has no
adverse affect (while refusing to match them certainly can).
in an "include" statement in either SPICE or verilog. Modified pin
matching behavior to force cells in both netlists to be marked as
black-box entries if either one is marked as a black-box entry (this
may not be needed, but shouldn't do any harm, either).
a different way of treating "black box" cells. Even when the
"-blackbox" option is specified, any cell that has no definition
will be treated as a black box. This allows comparison of a
black-box netlist against a non-black-box netlist, such as a
verilog netlist vs. a SPICE netlist, without forcing the black-box
attribute on the SPICE netlist. Then, if the SPICE netlist
contains cells without elements such as fill/decap/tap cells,
they can be flattened and removed instead of forcing an error or
requiring the use of "ignore".
<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).
"prefix" with the specified path during install, so that netgen can
be installed in a separate location to be migrated to the final
install location, without appending the entire install path to
DESTDIR.
they are converted to the double-backslash escape that is the proper
JSON syntax for backslashes, instead of being removed, which changes
the name and can be confusing.
handle verilog syntax. Also: Added SPICE voltage and current
sources as separate classes (as opposed to being converted to
subcircuits, which was how they were previously handled). That
allowed voltage sources to be checked for zero value and removed
by shorting the ends together, as was being done for zero value
resistors (note that like zero-value resistors, removal is only
done if removing the component makes a better match than leaving
it in). In particular, yosys has SPICE netlist output that
converts equality assignments ("assign a = b") into zero-value
voltage sources, so these components need to be treated as
non-physical elements.
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).
in verilog net names, which are apparently legal in verilog but not
in python strings (if not escaped). This is somewhat critical for
running the LVS GUI as yosys can generate backslashes in generated
net names in the synthesized netlist.
some problems stemming from comparing a case-sensitive netlist
against a case-insensitive one. Verilog netlist reading does
not yet have support for macros other than "`include", and it
does not yet have support for bit vectors constructed with
braces ({}).
Tim Edwards
Kamyar Mohajerani
D. Mitch Bailey
Ahmed Ghazy