when reading .ext files with "equiv" statements in them. The
generation of "equiv" statements was expanded recently, making it
more likely for this issue to show up. There may be devices in
a file that have a terminal node pointing to the node that gets
removed, and these must be updated to point to the node that
remains after merging. This requires a full loop over all
devices and so could have a potentially large impact; but in
general there are not many equiv statements (implying multiple
different labels attached to the same node) and so it is unlikely
that there would be a noticeable performance hit in practice.
gate and diffusion area on each pin is done before erasing parts
of the cell that are to be hidden by obstruction layers. That
preserves the antenna information even when "-hide" is used. This
corrects the issue raised by Kareem Farid in the github issue
tracker #236.
"space" is considered part of the substrate, then the check for
planes to search should exclude "space" from the type mask
first. Otherwise, all planes get searched, not just the substrate.
Also: The same routine can falsely flag a device terminal as
substrate if a split tile is marked as the device's region. This
was also fixed.
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).
of the cell. This will greatly help in diagnosing issues when
reading cells from multiple locations including cwd, relative
paths, PDK libraries, and the search path. Also: Reworked
the timestamp update message so that it prints all at once at
the end of processing, not printing output for every cell
processed as it is being processed. That prevents output from
the file read routine from getting interleaved with the
timestamp processing output.
labels that are not connected to their declared layers. It's the
latter type that need additional processing in ExtSubtree.
Limiting this processing significantly cuts down on processing
time when there are many labels in a layout, as happens with the
"def read -labels" command option.
can result in negative resistors due to integer overflow. In all
cases, the target was floating-point and it was only necessary to
recast everything to float first.
causing the SI suffix not to be the expected one. Adjusted the
bounds where each SI suffix is used to keep output in the range of
0.1 to 100, although the boundary is very subjective. Made a
correction to the extresist code to scan through all device records
for a tile type. However, (1) there are cases being missed, and (2)
this should not be necessary since all device types should be able
to be known exactly from the contents of the .sim file. Needs more
work.
window in the toolkit, which was to the "tkwait" command, which
waits for a change in state. What was intended was to wait for
a change in state to visible only; once visible, the "tkwait"
command should not invoked or else the process will block.
to "safer" strncpy() calls to prevent string buffer overflow.
Also: Reimplemented the loop in the GDS write routine that counts
ports and then outputs them in order. It was possible to hang
magic for a long time by giving a port a very, very large index
number. The new implementation uses qsort() to sort the ports
by index, which is obviously much more efficient for the worst
case (and efficient enough for all normal cases).
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).
inside a halo area. The previous implementation used a linear
accounting of error to determine the amount of shielding, but
since the shielding is nonlinear, this is a poor approximation
and regularly overestimates the shielding and leads to negative
capacitances. The corrected method makes many more calls to
the atan() function and the performance impact for extraction
will need to be evaluated.
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.
that aren't actually handled by the "lef write" command. The three
mentions are "LEFsource", "LEFuse", and "LEFshape", all of which
refer to names of pin properties, not macro properties. These
mentions were probably left over from early work.
(truly) missing a terminal (such as a MOSCAP made with a gate
extending into but not crossing a diffusion region). Added the
most requested GUI feature, which is a vertical scrollbar on the
parameterized device window (could be improved by maximizing
window height without exceeding display height).
222 from Sean Cross. Corrected a few places where the blanket
conversion "Region"->"ExtRegion" picked up some comment lines
that were unrelated to the structure name.
the cell being reworked for port numbering. Otherwise *all*
labels are selected, which can take a very long time depending on
how many labels are in the layout. Note: Need a "select area
ports" function, and better yet, rework the whole label database
so that magic no longer has to run compute-intensive routines
like DBEraseLabelsByContent().
"cif *hier write disable" and "cif *array write disable" commands
for a specific cell def and its descendents. The revision ensures
that all descendents apply the override. The "cif write" command
uses a stack instead of recursion, which makes it difficult to
apply the same method. Currently the method only works for the
"gds write" command, and implementing the feature for "cif write"
is deemed not worth the effort.
the "connected other node to. . ." message when terminals of a
device are shorted. A long enough node name, especially one
created by concatenating hierarchy when flattening a cell, can
easily overrun the short 256-byte string buffer. Fixed by
changing strcat() to strncat().
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.
2-terminal devices without complaining. The previous handling
seemed to be technically correct other than spitting out warnings
about missing terminals.
tech file "extract" section to work correctly when the offset is
negative. Generally, a negative offset is nonphysical and is just
curve-fitting round-off error, but the existing code was failing
to divide out the factor of 1000 that had been multiplied through
when reading the tech file, resulting in a very wrong offset.
when internal units no longer match lambda units. The text
would match the dimension of the cursor box, but the measurement
lines would be drawn assuming a lambda scale, not the internal
scale.
isolate the terminal areas of a device (e.g., source and drain)
and calculate their area and perimeter individually for the
device (in addition to the traditional method of calculating
area and perimeter of each resistance class for the entire node).
Also: Reworked the SPICE syntax output to generate SI values
in the range 1-1000 with the appropriate suffix (e.g., "20u")
instead of defaulting to "u" for lengths and "p" for areas.
This prevents it from producing weird units like "150000u" when
a process definition already includes a scalefactor.
Reworked the "extresist" code to use the device terminal area
and perimeter. This fixes an error in which "extresist" would
lose these values and "ext2spice" with option "extresist on"
would generate a new netlist output with zero terminal areas
and perimeters.
transistor records match between the ".ext" file and the ".res.ext"
file for the number of terminals per device. Previously, the first
device type for the layer type was always being used, and if it had
fewer terminals (e.g., a MOScap), then one terminal would go missing
in the output.
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.
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.
213 from Anton Blanchard (1. Don't cast pointer to struct and back
again in DBDiagonalProc(), 2. Fix compiler warning in
drcMaskSpacing(), 3. Fix a few issues in leaDBSearchForTech(),
4. Remove spurious ";" from PlotPS()).
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.
tech file to correct the underlying problem with the SkyWater
sky130 process in which a different layer/purpose pair is used
for TEXTTYPE and DATATYPE for the same layer. Previously, all
output from magic writes the same pair for both when writing a
port label. The new method preserves existing syntax, although
there are some differences based on what order the "port"
statement appears relative to other types for the same layer.
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.
use of a resistor type as a FET extended drain, allowing the
FET drain node to short across to the other side of the resistor
so that the resistor is absorbed into the FET device. Used with
the GF180MCU process to describe the salicide-block ESD FET types.
for compatible layout over the area of the pin rectangle in the
entire hierarchy of the cell, not just in the top level. This
corrects issues where pins are placed in the top level cell with
no metal underneath. It is written in such a way that it will
work regardless of whether paint is split across the hierarchy,
or the label spans different types (such as crossing a contact).
in the input. The name of one was being modified but was being
right-justified into the string, resulting in a name starting with
many space characters. Also: Fixed an issue with extresist where
a label that ends up with an empty string can become a node with
an empty string name in the .res.ext file output.
number of terminals for devices that don't have the usual gate/
source/drain terminals (e.g., diodes, resistors, capacitors) when
writing the devices with re-mapped terminals into the .res.ext
file. Also: Changed the size of the word containing the name
refcount for "equiv" statements, since an accidental shorting
of pins can cause a large number of "equiv" statements in a .ext
file, causing an overrun of the previously 1-byte refcount (this
probably does not make the structure any longer, since it likely
has to fit to a word boundary).
implement a GF DRC rule. This variant allows for a difference
between the minimum allowed surround on one side and the amount
that must be extended on the adjacent side.
pin on a compatible area due to an incorrect type mask. (Also
note that this routine only works (after correction) for RECT
statements, but there should be a similar check for POLYGON
statements.)
Tim Edwards