behavior when a child coordinate is not specified; otherwise,
the original code's setting of the child reference point to the
bounding box lower left causes the lower left point to be
used always, which is not how the getcell command is supposed to
function.
to place a cell in a meaningless position for any rotation and flip
combination other than zero. The issue was that the reference point
was not rotated along with the cell.
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).
"unexpected asymmetric device" is printed prematurely, as it
is inside a loop checking over all device entries compatible
with a device type. Also: Flagged an issue with the "label"
keyword in the "cifinput" section of a tech file. The "label"
keyword cannot be used in conjunction with boolean operators.
It can only connect labels on a specific GDS type to one magic
type. Unfortunately, because this was not flagged before as
an error or warning, the incorrect usage has crept into a lot
of tech files. This uncovers an underlying issue that labels
must be allowed to automatically reconnect types, which is
undermined by the "no-reconnect-labels" cifinput option. That
issue will be addressed in an upcoming commit.
so that it does not fail if an edit cell is not loaded, but
simply loads the default unnamed edit cell. This is somewhat bad
behavior in the case of reading GDS, since if the GDS is a library
and does not have a top level cell that matches the name of the
GDS library, then the edit cell that is loaded when the "gds read"
command is issued remains unchanged, so it didn't need to be there
in the first place. Fixing this to behave better would require a
bit of additional work.
the time the option was implemented), and also implemented (and
documented!) a similar command option "extract stepsize" for
reporting or changing the extraction step size.
argument, which is supposed to flatten all selected instances.
After flattening, instead of deleting the instance from the
cell, it deleted the instance from the selection, leaving the
one in the cell.
of command logging, which caused the "select cell <instance>" command
option to become invalid; this command option is used by the
parameterized cell generator and makes it impossible to edit the
parameterized cells.
meaning of the MAG record in GDS files. Most available GDS
documentation is decidedly vague about what MAG means. Most
layout tools seem to interpret a MAG of 1 as corresponding to a
text height of 1um. However, there are a few tools that
interpret it as 1 centimicron, and there's no reason to assume
that any given interpretation is correct. "gds magscale" allows
the scale to be redefined.
"pick x y" which acts like "cursor", but operates on a database
coordinate instead of a pointer coordinate. Made a few other
corrections to the command logging code so that it produces
valid output when the log file is sourced.
commands that make use of the pointer position have an equivalent
command that operates solely on layout coordinates, or otherwise
avoids needing a pointer position. Added the command option
"down <instance>" to avoid using the pointer to disambiguate
selections. Added the command option "select ... at x y" to
do paint or cell selections at a specific coordinate instead of
the pointer position.
of the "edit" command that takes an instance name as an argument.
This is the first of a small series of command extensions to
provide the capability to replace any command that is dependent on
the pointer position with an equivalent command that is not, for
the purpose of removing pointer and screen coordinate dependencies
from the log file created by "logcommands".
"drc printrules". Implemented a new "drc" command option called
"drc ignore", which can be used to suppress reporting of specific
rules, for both "drc why" and "drc find". This can help with
finding an error buried among a large number of other errors.
with "extract do local" now being equivalent to "extract path .".
This allows extraction files to be put in a subdirectory and not
clog up the current working directory. Also: Fixed some behavior
around the use of "ext2spice -p <path>" so that it (1) works, and
(2) is compatible with the new "extract path". Since the ext2spice
and ext2sim commands are effectively independent of the primary
extraction, the "-p" option is needed to correspond to the use of
"extract path". Hopefully this is seen as only a minor inconvenience.
previous behavior that had inadvertently been changed. In recent
versions, "load <absolute_path> -dereference" would incorrectly
apply the dereferencing to <absolute_path> rather than just its
subcells. Cleaned up the code around DBCellRead() in the process,
so everything is more straightforward (although probably more
could be done in that regard).
dereferencing, and making the behavior of "load" on the command
line (i.e., loading a cell from a file) the same as the
behavior of loading a cell as a result of expanding an unloaded
instance. In both cases, if "load -dereference" is used, and
a cell does not exist in any search path but does exist in the
original location, without dereferencing, then the cell will be
loaded from the original location. Also: Corrected an error
that has existed since adding the capability to read compressed
files, which causes magic to crash when attempting to run the
"crash recover" command (because that routine was mixing
compressed and regular file stream calls).
computing the amount of fringe shielding was wrong. This fixes
one of my example cases, but not the other one, so I still need to
pin down a condition that can result in negative capacitance.
natural sort instead of ASCII-based sorting, so that ports that
are numbered arrays will be indexed properly by count. Also:
Modified the "extresist" handling of substrate to draw the default
substrate type over the entire cell area (less areas of nwell or
other conflicting type). This allows extresist to extract the
entire substrate as a resistive network. The result is ugly and
may warrant some aggressive network simplification, but it should
at least be realistic.
This is diagnostic only and does not change the read-in
behavior.
(2) ext2spice: Corrected an error that had been introduced
into version 8.3.171 that accidentally marks all devices
as visited which causes all source/drain areas and
perimeters to be output as zero.
(3) extract: Sweeping changes to handling of fringe
capacitance. Removed the (recently added) "fringeshieldhalo"
parameter from the tech file. Reworked the fringe
capacitance models based on results from the "capiche"
project (github/RTimothyEdwards/capiche). Fringe shielding
is now done by clipping fringe at the boundary of a
shielding shape, rather than trying to calculate the
amount of shielding (as the "capiche" project proved this
to be equivalent). Values for partial fringing are modeled
by atan(x), which like the sidewall (1/x) curve, extends to
infinity and values are limited by the halo but do not
otherwise depend on the halo. Because of this, the halo can
be made variable and controlled by the user for deciding on
the tradeoff between accuracy and run time. A new command
option "extract halo" was added to allow this control over
the halo distance.
"gds polygon subcells true" the same as "gds polygon subcells
temporary" instead of "gds polygon subcells keep". This works
well for gf180mcu in open_pdks to keep the existing behavior
but won't break the GDS input on an older version of magic.
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.
of a label from the command line. Also fixed a long-standing
irritation that "setlabel" would change the properties of a label
in the edit cell but not in the selection itself, which would
cause the label to be drawn both with the original properties
in the selection and the new properties in the edit cell. Now
both views will track the same changes.
natural flattening from a selection. That is, instead of
specifying "flatten -doinplace <cell>", you can select some
number of instances and just do "flatten -doinplace".
flattening, since the appearance of the layout will change even
though there are no physical changes. Finally got around to
debugging and correcting the input mask-hints, which can
preserve vendor GDS by marking areas where the vendor GDS differs
from magic's automatically generated output (the method was
almost correct and only needed an input scale factor change).
commit to prevent port labels from being copied up from the
flattened cell into the parent, and prefixing the instance
name to text in the instance top level so that there will be
no port or label collisions in the parent cell after flattening
the child cell in place. Also: Changed "extract dolabelcheck"
to be the default setting.
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.
supported). Fixed the long-standing issue in which DRC does not
get stopped by the "drc off" command (the behavior for interrupting
the DRC was dependent on the DRC being turned on, and the "drc off"
command was turning it off before breaking, causing the interrupt
to be ignored).
attempt is made to write an abstract view to GDS. This behavior can
be overridded with the new command option "gds abstract [enable|disable]".
Also: Corrected extraction to allow split tiles to be set as the
reference tile for a node. Previously this was allowed only if the
tile was the first to be searched, but that can cause different tiles to
be marked as the reference depending on where the search starts,
resulting in different names for the same node in .ext files, which is
bad. Also: Modified the LEF annotation to avoid bad entries in the LEF
that would create layers in the layout where none exist.
Alessandro De Laurenzis. That pull request cleaned up the vast
majority of compiler warnings. However, that cleanup exposed a
few additional warnings pointing to errors in the code that needed
fixing. The code now compiles cleanly except for one warning
about redefined CAD_DIR that I have not looked into.
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.
flattening based on cells which have a property "flatten". Also:
Modified the DEF read and write to convert DIEAREA into a
FIXED_BBOX property. This solves issues with placing of components
from DEF, when those components may not have have come from place &
route and may not have P&R bounding boxes. Also: Fixed the
documentation for the "dump" command, which was missing the optional
orientation in the description.
alternative separator "." instead of "/". This prevents other
routines that expect "/" to indicate a true hierarchy from treating
the label as hierarchical instead of flat, which should be the
correct handling for a flattened cell.
Previous commits changed the port IDs to an integer rather than a
bitfield. However, the first and next commands were utilizing that
a -1 became a large positive integer when masked. This resulted in
the min port operations failing. Added a default comparison with -1
to fix the problem.
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.
of systems calls to "gzip" and "gunzip". A compressed GDS file can
be made simply by doing "gds write <name>.gds.gz", and can be read
simply by doing "gds read <name>.gds.gz". Names of compressed files
can be put in the GDS_FILE property of a cell.
to NULL for a read-only view. . . Changed the command "what" so that
it will not fail on a non-edit cell. There are likely a few other
commands that should not fail on non-edit cells because they do not
alter anything.
Tim Edwards
Johan Euphrosine
Alessandro De Laurenzis
mrg