intent to handle multiple isolated substrate regions. A previous
version of this was added to the master branch but that method had
too many issues and is being deprecated. This version is also very
experimental and is a work in progress.
support asymmetric FETs and other devices like bipolars that have
three distinct terminals. This does not go as far as it should to
make the array independent of the number of declared terminals of
the device. However, it suffices to make, e.g., parameter "a2=area"
work for a bipolar device, and to generate the right drain and source
areas and perimeters for asymmetric (e.g., extended-drain) devices.
supposed to pull "sticky labels" into the cumulative flattened
layout. Because it failed to check for the "sticky" flag, it
would copy all labels, causing extraction time to go exponential
as the number of labels in the design increases. Based on this
correction, the extHierConnectFunc1() routine should be able to
be optimized by stopping the search for sticky labels on the first
non-sticky label, since extSubtreeFunc() ensures that all sticky
labels come first in the label list.
substrate more than once for the same subcell, since the substrate
extraction method scans the entire plane area; this was making
large standard cell layouts extract very slowly, as every component
cell was causing the substrate search to be repeated.
extraction: Fixed a problem causing long extraction times, at
least some of which had to do with a poor string hash function
implementation. Fixed a huge problem in ext2spice, where the
node merge function was particularly poorly implemented, causing
exponentially increasing processing times with layout size.
Corrected a minor issue with ext2spice where arguments were
improperly specified, causing unnecessary error messages to be
issued. Fixed an error in the "load -dereference" command option,
which again caused unnecessary error messages to be issued.
Changed .gitignore to ignore Depend files, which are now regenerated
on every build.
extraction times, which is an incorrect units conversion of the
"step" parameter in the extract section. It was converting based
on the "lambda" parameter in the same section, which has to do with
the scaling of values in the output file, not the scale factor of
the database to be extracted, which is set by the current CIF output
scale. Once fixed, extraction times are minimized using the rule of
thumb mentioned in the techfile reference, which is 50 times the
minimum feature size. Also: Give the lengthy nature of extraction
on large designs no matter how well optimized, added a feature to
mark the progress of the extraction in increments of 5%. Does not
output progress for small cells that extract quickly.
development had been halted since it was first created back in April.
Version 8.2 is now the official development version, with the first
development push to create a Cairo graphics interface.
Tim Edwards