no way to implement boolean operators on labels, so any "label"
statement in the section can apply only to one magic layer. This
is regularly violated in most (all?) techfiles (due mainly to lack
of explanation and guidance). The addition of the "no-reconnect-
labels" option for cifinput made it worse, as it can cause a label
to be attached to the wrong layer and be stuck that way. Even
without the option, an attachment to a non-connecting type is a
problem; DIFF cannot simultaneously have a connection to both
ndiff and pdiff, so it will be one or the other, and the one not
connected can easily get labels moved to other nets. To avoid
this: (1) removed the "no-reconnect-labels" option, and (2) made
the automatic label reconnection smarter, as well as splitting it
into two different behaviors based on whether a label is being
created or manipulated from the command line (more or less the
original behavior) vs. being read from GDS or LEF. The new rules
assume that labels attached to a GDS type will all map to the
same plane in magic. To avoid excessive error messages from
existing tech files, a warning is issued only if "labels" changes
the plane of the target layer (a realistic solution rather than
the preferred one). Also: Fixed an error that causes a crash on
the "wizard" command "*watch" if the cell being observed is
read-only (see github issue #271).
ground node name (which is static) gets put on the node list and
is improperly deallocated. Corrected by simply allocating the
string for the default substrate node instead of using the static
string.
three types: "none", "temporary", and "keep" (instead of "true"
or "false"). "none" now reverts back to the original behavior,
because it was found that saving polygons in subcells prevents
them from participating in boolean operations. The "keep"
option is the original option (polygons kept in subcells), and
"temporary" is the one recently introduced (which puts polygons
in subcells and then flattens them). This restores the original
method while retaining the recently implemented method. However,
a proper solution needs to be found that deals with the problem
of boolean operators.
that the feature for implementing callbacks on a selection list
was already implemented via the add_dependency procedure.
Modified the GDS read to remove cell instances that are placed
directly on top of one another in the same cell. Modified the
GDS read to make a better selection of a default font size for
text that specifies a font but not a size, using the minimum
width for the layer the text is placed on. Modified the GDS
read to remove text with empty-string placeholders (created when
a pin layer is read but no text exists to go along with it, due
to GDS not having a specific way to make pins, such that pins
have to be split between one record for geometry and another
for text).
should have been done a long time ago! Allows an instance to be
flattened in place inside a cell def, which otherwise requires
a complicated set of commands to do. Also: Modified the polygon
handling routine from the previous commit so that it correctly
removes the polygon cell defs after flattening them into the
parent cell.
can be much, much faster than reading in polygons directly into a
cell from GDS. Modified the handling of polygons so that they are
*always* read into subcells. If the "polygon subcell flatten true"
option is not enabled, then the subcells are flattened at the end
of reading the cell, and the polygon cells are deleted. This method
avoids most of the cases in which "polygon subcell flatten true"
has ever needed to be set.
This commit makes the code (mostly) C99-compatible, enabling to compile
it without the -Wno-error=implicit-function-declaration flag. This
way, Magic becomes usable on arm64 architectures, specifically on Apple
computers with M1/M2 SoC.
fringe capacitance halo where the default halo distance was set to
zero instead of one and caused divide-by-zero issues; (2) Found
extraction issues where labels picked up from cells flattened
during GDS reading cause the flattened/emptied cells to show up
in the extraction with extra pins that can mess up LVS. Solved
this by removing labels from flattened/emptied cells.
reading GDS files, caused by an unneeded change to pass both
the "original" filename and the actual filename when handling
compressed files---The original filename is unneeded.
(2) Implemented several new methods for parasitic extraction. The
first is an option offset value to apply to sidewall calculations.
This handles issues where actual wire separation is different
from drawn wire separation, which can be significant for the
1/d calculation of sidewall coupling. The second method is to
use the recently-added fringe halo to compute the coupling of the
fringe capacitance to nearby wires. Prior to this change, all
fringe capacitance was applied to surfaces directly under a wire
edge as if the fringe capacitance did not extend outward from the
edge. Now the capacitance is properly pro-rated for the position
of any overlapped shape inside the fringing field. Finally, the
third method added is a new search algorithm for finding the
nearest shapes along the length of a boundary. This is used for
sidewall coupling and fringe shielding, where the nearest shape
dominates the coupling, and any shapes behind are shielded and
may (to first order) be ignored. Previously, the entire halo
was searched without regard to shapes shielding other shapes
behind, and a recent correction added an ad-hoc search for
blocking shapes that was inefficient and not always correct.
The new method is both efficient and accurate.
Compression levels of the output can be controlled with the "gds
compress [<value>]" command, where <value> 0 (default) is uncompressed
output, 6 is "normal" gzip compression, and 9 is maximum compression.
pointing GDS_FILE to a compressed filename when using "gds readonly
true" on a compressed file. The start and end pointers still point
to data bounds in the uncompressed file.
timestamps that are fixed, since the timestamp update routine is
called from too many places, too many times. Instead created a
new cell definition flag indicating a fixed timestamp, which can
be set by "cellname timestamp" for an individual cell, or with
"gds datestamp" for cells read from a GDS file.
the timestamp is updated after reading in CIF or GDS, and managed to
get the timestamp dirty flag to remain clear after reading when
"gds datestamp" is used. This includes a modification of the timestamp
update routine that only updates timestamps on a single file if only a
single file is being written.
"writeall force <cell>" is used but <cell> doesn't exist, and (2)
to add options "writeall modified" and "writeall noupdate" (which
may or may not be useful).
yesterday's commit to allow the syntax "gds maskhints <types>", in
which mask hints can be restricted to a specific list of layers
rather than all layers which define mask hints in the cifoutput
rule.
behavior, in which all cells read from GDS are given a zero
timestamp, and the timestamp is set when the file is written to
disk, the default behavior now is to set the layout cell's timestamp
from the timestamp provided in the GDS (the creation date timestamp,
specifically). The same command "gds datestamp" implemented in the
previous commit for GDS writes now also applies to GDS reads: If
set to "no", then the timestamp value from the GDS file is
transferred to the layout view (default behavior); if set to "yes",
then the timestamp is set to zero (legacy behavior). If set to
a value, then the value is used as the timestamp.
in a cell to account for the difference between what's in an input
GDS file and what magic would write out itself from the processed
data. This potentially allows library cells to be read in that
will generate the equivalent mask data as output without resorting
to using GDS file references as properties. The method is activated
with the new command option "gds maskhints on" and the default is
off.
If cells are instanced before being defined, causing the GDS parser
to rewind the cell from the top, then the "already defined" error
messages will be suppressed, since it is to be expected that cells
will be seen twice (and ignored the 2nd time). When rewinding, an
output message is issued so that it is clear that the file contains
instances that are used before they are defined, and recommends the
"gds ordering on" setting. Also: Fixed the "gds ordering" command
code so that the command with no third argument returns the state
of the "gds ordering" setting instead of generating a parser error.
post error messages when a GDS library addendum is read. It now
assumes that if a cell is called but not defined in the GDS, and
that cell happens to be in memory already, then this is intentional.
from 98 (arbitrarily selected) to 61 (apparently commonly used by
other tools). This should help increase compatibility with GDS
files output from other tools.
in which if a cell is read from GDS that has the same name as a cell
in memory, then the cell in memory is renamed to keep all cell names
unique in the database.
This can be done now by reading a LEF file, followed by reading
a GDS file with the "noduplicates" option set. In addition,
annotation of either the LEF view or a read-only view follows the
same protocol as cell paths in the .mag file, which is to replace
leading path components matching Tcl variables for PDKPATH or
PDKROOT, and replace the home directory path with a tilde.
flattened per "gds flatten" or "gds flatglob", and the "gds readonly"
option is not set, then the instances of the flattened cells are
removed from the layout. They are retained for the "readonly" option
because when writing GDS of such a cell, the full hierarchy needs to
be walked.
from slashes in hierarchical names. Magic does not allow slashes
in names when using "identify", so the simplest solution is just
to prohibit them in names being read from GDS files, and replace
them with underscores to make them magic-compatible. Changing
GDS names always has repercussions on things like back-annotating
delays, so it should probably be revisited in the future.
of input cells on a per-cellname basis, using glob-style pattern
matching. This is probably the best way to deal with 3rd-party vendor
GDS with unfortunate practices like dividing devices up among cells in
a hierarchy, even though it comes across as a bit of a hack solution.
routine attempts to rescale the contents of the top-level cell after
moving forward in the GDS to find a cell that was used before it was
defined, if reading that cell caused the scale to change. However,
the numerator and denominator were reversed, causing the scaling to
be the inverse of what it should have been.
to allow a "gds read" command to ignore cells in the GDS which already
exist in memory. This allows magic to be "pre-seeded" with specific
views of cells in the GDS. Default is false, which is backwards-
compatble behavior. (2) Changed the behavior of the the way the use
path is written to and read from a .mag file, checking the path prefix
against Tcl variables PDK_PATH, PDKPATH, PDK_ROOT, and PDKROOT, and
replacing any such leading path component with the variable name.
On reading a .mag file, any variable name at the start of the path
that matches a Tcl variable will be substituted.
used both for counting cells during GDS write and for saving
geometry data from the "copyup" operator during GDS read. The write
routine does not clear the client record, and the read routine was
checking if the cd_client value was default. Corrected the resulting
crash condition by resetting cd_client before GDS reads. However, the
underlying problem is that the GDS read is reading data into a cell
that already exists in the database, and is not handling it robustly
by renaming the existing cell. So this should be revisited.
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.
limit of the Calma definition, and probably has not done so for ages.
Nobody informed me of this. The restriction has been lifted from
GDS input and output in Magic. It can be reinstated if necessary by
setting a flag in the cifoutput section of the techfile, but it is
likely that this will not be necessary unless there are other tools
that enforce the limit and will not read a GDS file that exceeds it.
item that was never properly validated. Corrected the root of the
problem, which was an attempt to deallocate memory that had never
been allocated in the first place.
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
Alessandro De Laurenzis