The new bitwise case equality (`$bweqx`) and bitwise mux (`$bwmux`)
cells enable compact encoding and decoding of 3-valued logic signals
using multiple 2-valued signals.
In 2fcc1ee72e, the following is apparantly added in order to mark any
number of undefined LUT inputs:
lut_a.append(RTLIL::Const(State::Sx, minlut - input_nodes.size()));
However this can only be done if the number of input nodes is less
than minlut.
This fixes#3317
After speaking with the author of ABC he let me know that ifraig is a very old command, and that &get; &fraig -x; &put is over 100x faster than ifraig with improved PPA results.
After making the change I confirmed that this is in fact a major speed up. On our internal designs in O(millions) of standard cells we saw multi hour reductions in runtime.
Also included is an improvement to the dress command. Using AIG based transformations removes the spec it SATs against. Proving the input blif will make sure that no matter what commands are run the dress command can still do its job. I noticed a regression against some LUT mapping jobs that prompted me to fix this.
Uses the regex below to search (using vscode):
^\t\tlog\("(.{10,}(?<!\\n)|.{81,}\\n)"\);
Finds any log messages double indented (which help messages are)
and checks if *either* there are is no newline character at the end,
*or* the number of characters before the newline is more than 80.
POSIX defines $TMPDIR as containing the pathname of the directory where
programs can create temporary files. On most systems, this variable points to
"/tmp". However, on some systems it can point to a different location.
Without respecting this variable, yosys fails to run on such systems.
Signed-off-by: Mohamed A. Bamakhrama <mohamed@alumni.tum.de>
- Attempt to lookup a derived module if it potentially contains a port
connection with elaboration ambiguities
- Mark the cell if module has not yet been derived
- This can be extended to implement automatic hierarchical port
connections in a future change
- FfData now keeps track of the module and underlying cell, if any (so
calling emit on FfData created from a cell will replace the existing cell)
- FfData implementation is split off to its own .cc file for faster
compilation
- the "flip FF data sense by inserting inverters in front and after"
functionality that zinit uses is moved onto FfData class and beefed up
to have dffsr support, to support more use cases
- *_en is split into *_ce (clock enable) and *_aload (async load aka
latch gate enable), so both can be present at once
- has_d is removed
- has_gclk is added (to have a clear marker for $ff)
- d_is_const and val_d leftovers are removed
- async2sync, clk2fflogic, opt_dff are updated to operate correctly on
FFs with async load
There will soon be more (versioned) memory cells, so handle passes that
only care if a cell is memory-related by a simple helper call instead of
a hardcoded list.
* xilinx: add SCC test for DSP48E1
* xilinx: Gate DSP48E1 being a whitebox behind ALLOW_WHITEBOX_DSP48E1
Have a test that checks it works through ABC9 when enabled
* abc9 to break SCCs using $__ABC9_SCC_BREAKER module
* Add test
* abc9_ops: remove refs to (* abc9_keep *) on wires
* abc9_ops: do not bypass cells in an SCC
* Add myself to CODEOWNERS for abc9*
* Fix compile
* abc9_ops: run -prep_hier before scc
* Fix tests
* Remove bug reference pending fix
* abc9: fix for -prep_hier -dff
* xaiger: restore PI handling
* abc9_ops: -prep_xaiger sigmap
* abc9_ops: -mark_scc -> -break_scc
* abc9: eliminate hard-coded abc9.box from tests
Also tidy up
* Address review
This change set contains a number of bug fixes and improvements related to
scoping and resolution in generate and procedural blocks. While many of the
frontend changes are interdependent, it may be possible bring the techmap
changes in under a separate PR.
Declarations within unnamed generate blocks previously encountered issues
because the data declarations were left un-prefixed, breaking proper scoping.
The LRM outlines behavior for generating names for unnamed generate blocks. The
original goal was to add this implicit labelling, but doing so exposed a number
of issues downstream. Additional testing highlighted other closely related scope
resolution issues, which have been fixed. This change also adds support for
block item declarations within unnamed blocks in SystemVerilog mode.
1. Unlabled generate blocks are now implicitly named according to the LRM in
`label_genblks`, which is invoked at the beginning of module elaboration
2. The Verilog parser no longer wraps explicitly named generate blocks in a
synthetic unnamed generate block to avoid creating extra hierarchy levels
where they should not exist
3. The techmap phase now allows special control identifiers to be used outside
of the topmost scope, which is necessary because such wires and cells often
appear in unlabeled generate blocks, which now prefix the declarations within
4. Some techlibs required modifications because they relied on the previous
invalid scope resolution behavior
5. `expand_genblock` has been simplified, now only expanding the outermost
scope, completely deferring the inspection and elaboration of nested scopes;
names are now resolved by looking in the innermost scope and stepping outward
6. Loop variables now always become localparams during unrolling, allowing them
to be resolved and shadowed like any other identifier
7. Identifiers in synthetic function call scopes are now prefixed and resolved
in largely the same manner as other blocks
before: `$func$\func_01$tests/simple/scopes.blk.v:60$5$\blk\x`
after: `\func_01$func$tests/simple/scopes.v:60$5.blk.x`
8. Support identifiers referencing a local generate scope nested more
than 1 level deep, i.e. `B.C.x` while within generate scope `A`, or using a
prefix of a current or parent scope, i.e. `B.C.D.x` while in `A.B`, `A.B.C`,
or `A.B.C.D`
9. Variables can now be declared within unnamed blocks in SystemVerilog mode
Addresses the following issues: 656, 2423, 2493
- Signed cell outputs are sign extended when bound to larger wires
- Signed connections are sign extended when bound to larger cell inputs
- Sign extension is performed in hierarchy and flatten phases
- genrtlil indirects signed constants through signed wires
- Other phases producing RTLIL may need to be updated to preserve
signedness information
- Resolves#1418
- Resolves#2265
When an adffe is being legalized, and is not natively supported,
prioritize unmapping to adff over converting to dffsre if dffsre is not
natively supported itself.
Fixes#2361.
The only difference between "RTLIL" and "ILANG" is that the latter is
the text representation of the former, as opposed to the in-memory
graph representation. This distinction serves no purpose but confuses
people: it is not obvious that the ILANG backend writes RTLIL graphs.
Passes `write_ilang` and `read_ilang` are provided as aliases to
`write_rtlil` and `read_rtlil` for compatibility.
For connection `assign a = b;`, `sigmap(a)` returns `b`. This is
exactly the opposite of the desired canonicalization for driven bits.
Consider the following code:
module foo(inout a, b);
assign a = b;
endmodule
module bar(output c);
foo f(c, 1'b0);
endmodule
Before this commit, the inout ports would be swapped after flattening
(and cause a crash while attempting to drive a constant value).
This issue was introduced in 9f772eb9.
Fixes#2183.
This parameter will resolve to the name of the cell being mapped. The
first user of this parameter will be synth_intel_alm's Quartus output,
which requires a unique (and preferably descriptive) name passed as
a cell parameter for the memory cells.
Those can be created by `opt_dff` when optimizing `$adff` with const
clock, or with D == Q. Make dfflegalize do the opposite transform
when such dlatches would be otherwise unimplementable.
This ensures that, when both sync and async FFs are available and abc9
is involved, the sync FFs will be used, and will thus remain available
for sequential synthesis.
I think these were probably missed by accident. Spotted because GCC
spits out lots of messages like this:
passes/techmap/dfflegalize.cc:114:7: warning: zero-length gnu_printf format string [-Wformat-zero-length]
114 | log("");
| ^~
(because we tell GCC that the first argument to log() looks like a
printf control string in log.h, and a zero length such string triggers
a warning).
Before this commit, `flatten` matched the template objects with
the newly created objects solely by their name. Because of this,
it could be confused by code such as:
module bar();
$dff a();
endmodule
module foo();
bar b();
$dff \b.a ();
endmodule
After this commit, `flatten` avoids every possible case of name
collision.
Fixes#2106.
`flatten` cannot derive modules in most cases because that would just
yield processes, and it does not support `-autoproc`; in practice
`flatten` has to be preceded by a call to `hierarchy`, which makes
deriving unnecessary.
After splitting the passes, some options can never be activated,
and most conditions involving them become dead. Remove them, and also
all of the newly dead code.
Although the two passes started out very similar, they diverged over
time and now have little in common. Moreover, `techmap` is extremely
complex while `flatten` does not have to be, and this complexity
interferes with improving `flatten`.
Lofty
Claire Xenia Wolf
Jannis Harder
Dag Lem
N. Engelhardt
Ethan Mahintorabi
KrystalDelusion
Miodrag Milanovic
Catherine
Marcelina Kościelnicka
Mohamed A. Bamakhrama
gatecat
Anton Blanchard
YRabbit
Zachary Snow
Paul Annesley
Eddie Hung
Robert Baruch
Peter Gadfort
Tobias Faller
clairexen
Rupert Swarbrick
Anonymous Maarten
Alberto Gonzalez