$ sudo apt-get install build-essential clang bison flex \
libreadline-dev gawk tcl-dev libffi-dev git \
graphviz xdot pkg-config python3 libboost-system-dev \
- libboost-python-dev libboost-filesystem-dev
+ libboost-python-dev libboost-filesystem-dev zlib1g-dev
Similarily, on Mac OS X MacPorts or Homebrew can be used to install dependencies:
$ brew tap Homebrew/bundle && brew bundle
$ sudo port install bison flex readline gawk libffi \
- git graphviz pkgconfig python36 boost
+ git graphviz pkgconfig python36 boost zlib
On FreeBSD use the following command to install all prerequisites:
# pkg install bison flex readline gawk libffi\
- git graphviz pkgconfig python3 python36 tcl-wrapper boost-libs
+ git graphviz pkgconf python3 python36 tcl-wrapper boost-libs
On FreeBSD system use gmake instead of make. To run tests use:
% MAKE=gmake CC=cc gmake test
For Cygwin use the following command to install all prerequisites, or select these additional packages:
- setup-x86_64.exe -q --packages=bison,flex,gcc-core,gcc-g++,git,libffi-devel,libreadline-devel,make,pkg-config,python3,tcl-devel,boost-build
+ setup-x86_64.exe -q --packages=bison,flex,gcc-core,gcc-g++,git,libffi-devel,libreadline-devel,make,pkg-config,python3,tcl-devel,boost-build,zlib-devel
There are also pre-compiled Yosys binary packages for Ubuntu and Win32 as well
as a source distribution for Visual Studio. Visit the Yosys download page for
yosys> help help
-reading the design using the Verilog frontend:
+reading and elaborating the design using the Verilog frontend:
- yosys> read_verilog tests/simple/fiedler-cooley.v
+ yosys> read -sv tests/simple/fiedler-cooley.v
+ yosys> hierarchy -top up3down5
writing the design to the console in Yosys's internal format:
yosys> write_ilang
-elaborate design hierarchy and convert wand/wor nets to logic:
-
- yosys> hierarchy
-
convert processes (``always`` blocks) to netlist elements and perform
some simple optimizations:
yosys> write_verilog synth.v
-a similar synthesis can be performed using yosys command line options only:
-
- $ ./yosys -o synth.v -p hierarchy -p proc -p opt \
- -p techmap -p opt tests/simple/fiedler-cooley.v
-
or using a simple synthesis script:
$ cat synth.ys
- read_verilog tests/simple/fiedler-cooley.v
- hierarchy; proc; opt; techmap; opt
+ read -sv tests/simple/fiedler-cooley.v
+ hierarchy -top up3down5
+ proc; opt; techmap; opt
write_verilog synth.v
$ ./yosys synth.ys
-It is also possible to only have the synthesis commands but not the read/write
-commands in the synthesis script:
-
- $ cat synth.ys
- hierarchy; proc; opt; techmap; opt
-
- $ ./yosys -o synth.v tests/simple/fiedler-cooley.v synth.ys
-
-The following very basic synthesis script should work well with all designs:
-
- # check design hierarchy
- hierarchy
-
- # translate processes (always blocks)
- proc; opt
-
- # detect and optimize FSM encodings
- fsm; opt
-
- # implement memories (arrays)
- memory; opt
-
- # convert to gate logic
- techmap; opt
-
If ABC is enabled in the Yosys build configuration and a cell library is given
in the liberty file ``mycells.lib``, the following synthesis script will
synthesize for the given cell library:
+ # read design
+ read -sv tests/simple/fiedler-cooley.v
+ hierarchy -top up3down5
+
# the high-level stuff
- hierarchy; proc; fsm; opt; memory; opt
+ proc; fsm; opt; memory; opt
# mapping to internal cell library
techmap; opt
clean
If you do not have a liberty file but want to test this synthesis script,
-you can use the file ``examples/cmos/cmos_cells.lib`` from the yosys sources.
+you can use the file ``examples/cmos/cmos_cells.lib`` from the yosys sources
+as simple example.
Liberty file downloads for and information about free and open ASIC standard
cell libraries can be found here:
- http://www.vlsitechnology.org/synopsys/vsclib013.lib
The command ``synth`` provides a good default synthesis script (see
-``help synth``). If possible a synthesis script should borrow from ``synth``.
-For example:
+``help synth``):
- # the high-level stuff
- hierarchy
- synth -run coarse
+ read -sv tests/simple/fiedler-cooley.v
+ synth -top up3down5
- # mapping to internal cells
- techmap; opt -fast
+ # mapping to target cells
dfflibmap -liberty mycells.lib
abc -liberty mycells.lib
clean
-Yosys is under construction. A more detailed documentation will follow.
+The command ``prep`` provides a good default word-level synthesis script, as
+used in SMT-based formal verification.
Unsupported Verilog-2005 Features
through the synthesis. When entities are combined, a new |-separated
string is created that contains all the string from the original entities.
+- The ``defaultvalue`` attribute is used to store default values for
+ module inputs. The attribute is attached to the input wire by the HDL
+ front-end when the input is declared with a default value.
+
+- The ``parameter`` and ``localparam`` attributes are used to mark wires
+ that represent module parameters or localparams (when the HDL front-end
+ is run in -pwires mode).
+
- In addition to the ``(* ... *)`` attribute syntax, Yosys supports
the non-standard ``{* ... *}`` attribute syntax to set default attributes
for everything that comes after the ``{* ... *}`` statement. (Reset
$ yosys -p 'plugin -a foo -i /lib/libm.so; read_verilog dpitest.v'
- Sized constants (the syntax ``<size>'s?[bodh]<value>``) support constant
- expressions as <size>. If the expression is not a simple identifier, it
+ expressions as ``<size>``. If the expression is not a simple identifier, it
must be put in parentheses. Examples: ``WIDTH'd42``, ``(4+2)'b101010``
- The system tasks ``$finish``, ``$stop`` and ``$display`` are supported in