1Netlist(3) User Contributed Perl Documentation Netlist(3)
2
6 Verilog::Netlist - Verilog Netlist
7
9 use Verilog::Netlist;
10 # Setup options so files can be found
12 use Verilog::Getopt;
13 my $opt = new Verilog::Getopt;
14 $opt->parameter( "+incdir+verilog",
15 "-y","verilog",
16 );
17 # Prepare netlist
19 my $nl = new Verilog::Netlist(options => $opt,);
20 foreach my $file ('testnetlist.v') {
21 $nl->read_file(filename=>$file);
22 }
23 # Read in any sub-modules
24 $nl->link();
25 #$nl->lint(); # Optional, see docs; probably not wanted
26 $nl->exit_if_error();
27 foreach my $mod ($nl->top_modules_sorted) {
29 show_hier($mod, " ", "", "");
30 }
31 sub show_hier {
33 my $mod = shift;
34 my $indent = shift;
35 my $hier = shift;
36 my $cellname = shift;
37 if (!$cellname) {$hier = $mod->name;} #top modules get the design name
38 else {$hier .= ".$cellname";} #append the cellname
39 printf("%-45s %s\n", $indent."Module ".$mod->name,$hier);
40 foreach my $sig ($mod->ports_sorted) {
41 printf($indent." %sput %s\n", $sig->direction, $sig->name);
42 }
43 foreach my $cell ($mod->cells_sorted) {
44 printf($indent. " Cell %s\n", $cell->name);
45 foreach my $pin ($cell->pins_sorted) {
46 printf($indent." .%s(%s)\n", $pin->name, $pin->netname);
47 }
48 show_hier($cell->submod, $indent." ", $hier, $cell->name) if $cell->submod;
49 }
50 }
51
53 Verilog::Netlist reads and holds interconnect information about a whole
54 design database.
55 See the "Which Package" section of Verilog::Language if you are unsure
57 which parsing package to use for a new application.
58 A Verilog::Netlist is composed of files, which contain the text read
60 from each file.
61 A file may contain modules, which are individual blocks that can be
63 instantiated (designs, in Synopsys terminology.)
64 Modules have ports, which are the interconnection between nets in that
66 module and the outside world. Modules also have nets, (aka signals),
67 which interconnect the logic inside that module.
68 Modules can also instantiate other modules. The instantiation of a
70 module is a Cell. Cells have pins that interconnect the referenced
71 module's pin to a net in the module doing the instantiation.
72 Each of these types, files, modules, ports, nets, cells and pins have a
74 class. For example Verilog::Netlist::Cell has the list of
75 Verilog::Netlist::Pin(s) that interconnect that cell.
76
78 See also Verilog::Netlist::Subclass for additional accessors and
79 methods.
80 $netlist->lint
82 Error checks the entire netlist structure. Currently there are
83 only two checks, that modules are bound to instantiations (which is
84 also checked by $netlist->link), and that signals aren't multiply
85 driven. Note that as there is no elaboration you may get false
86 errors about multiple drivers from generate statements that are
87 mutually exclusive. For this reason and the few lint checks you
88 may not want to use this method. Alternatively to avoid pin
89 interconnect checks, set the $netlist->new (...use_vars=>0...)
90 option.
91 $netlist->link()
93 Resolves references between the different modules.
94 If link_read=>1 is passed when netlist->new is called (it is by
96 default), undefined modules will be searched for using the
97 Verilog::Getopt package, passed by a reference in the creation of
98 the netlist. To suppress errors in any missing references, set
99 link_read_nonfatal=>1 also.
100 $netlist->new
102 Creates a new netlist structure. Pass optional parameters by name,
103 with the following parameters:
104 implicit_wires_ok => $true_or_false
106 Indicates whether to allow undeclared wires to be used.
107 include_open_nonfatal => $true_or_false
109 Indicates that include files that do not exist should be
110 ignored.
111 keep_comments => $true_or_false
113 Indicates that comment fields should be preserved and on
114 net declarations into the Vtest::Netlist::Net structures.
115 Otherwise all comments are stripped for speed.
116 link_read => $true_or_false
118 Indicates whether or not the parser should automatically
119 search for undefined modules through the "options" object.
120 link_read_nonfatal => $true_or_false
122 Indicates that modules that referenced but not found should
123 be ignored, rather than causing an error message.
124 logger => object
126 Specify a message handler object to be used for error
127 handling, this class should be a Verilog::Netlist::Logger
128 object, or derived from one. If unspecified, a
129 Verilog::Netlist::Logger local to this netlist will be
130 used.
131 options => $opt_object
133 An optional pointer to a Verilog::Getopt object, to be used
134 for locating files.
135 parser => $package_name
137 The name of the parser class. Defaults to
138 "Verilog::Netlist::File::Parser".
139 preproc => $package_name
141 The name of the preprocessor class. Defaults to
142 "Verilog::Preproc".
143 synthesis => $true_or_false
145 With synthesis set, define SYNTHESIS, and ignore text
146 between "ambit", "pragma", "synopsys" or "synthesis"
147 translate_off and translate_on meta comments. Note using
148 metacomments is discouraged as they have led to silicon
149 bugs (versus ifdef SYNTHESIS); see
150 <https://www.veripool.org/papers/TenIPEdits_SNUGBos07_paper.pdf>.
151 use_pinselects => $true_or_false
153 Indicates that bit selects should be parsed and
154 interpreted. False for backward compatibility, but true
155 recommended in new applications.
156 use_vars => $true_or_false
158 Indicates that signals, variables, and pin interconnect
159 information is needed; set by default. If clear do not
160 read it, nor report lint related pin warnings, which can
161 greatly improve performance.
162 $netlist->dump
164 Prints debugging information for the entire netlist structure.
165
167 $netlist->find_interface($name)
168 Returns Verilog::Netlist::Interface matching given name.
169 $netlist->interfaces
171 Returns list of Verilog::Netlist::Interface.
172 $netlist->interfaces_sorted
174 Returns name sorted list of Verilog::Netlist::Interface.
175 $netlist->new_interface
177 Creates a new Verilog::Netlist::Interface.
178
180 $netlist->find_module($name)
181 Returns Verilog::Netlist::Module matching given name.
182 $netlist->modules
184 Returns list of Verilog::Netlist::Module.
185 $netlist->modules_sorted
187 Returns name sorted list of Verilog::Netlist::Module.
188 $netlist->modules_sorted_level
190 Returns level sorted list of Verilog::Netlist::Module. Leaf
191 modules will be first, the top most module will be last.
192 $netlist->new_module
194 Creates a new Verilog::Netlist::Module.
195 $netlist->new_root_module
197 Creates a new Verilog::Netlist::Module for $root, if one doesn't
198 already exist.
199 $netlist->top_modules_sorted
201 Returns name sorted list of Verilog::Netlist::Module, only for
202 those modules which have no children and are not unused library
203 cells.
204
206 $netlist->dependency_write(filename)
207 Writes a dependency file for make, listing all input and output
208 files.
209 $netlist->defvalue_nowarn(define)
211 Return the value of the specified define or undef.
212 $netlist->dependency_in(filename)
214 Adds an additional input dependency for dependency_write.
215 $netlist->dependency_out(filename)
217 Adds an additional output dependency for dependency_write.
218 $netlist->delete
220 Delete the netlist, reclaim memory. Unfortunately netlists will
221 not disappear simply with normal garbage collection from leaving of
222 scope due to complications with reference counting and weaking
223 Class::Struct structures; solutions welcome.
224 $netlist->files
226 Returns list of Verilog::Netlist::File.
227 $netlist->files_sorted
229 Returns a name sorted list of Verilog::Netlist::File.
230 $netlist->find_file($name)
232 Returns Verilog::Netlist::File matching given name.
233 $netlist->read_file( filename=>$name)
235 Reads the given Verilog file, and returns a Verilog::Netlist::File
236 reference.
237 Generally called as $netlist->read_file. Pass a hash of
239 parameters. Reads the filename=> parameter, parsing all
240 instantiations, ports, and signals, and creating
241 Verilog::Netlist::Module structures.
242 $netlist->read_libraries()
244 Read any libraries specified in the options=> argument passed with
245 the netlist constructor. Automatically invoked when netlist
246 linking results in a module that wasn't found, and thus might be
247 inside the libraries.
248 $netlist->remove_defines(string)
250 Expand any `defines in the string and return the results.
251 Undefined defines will remain in the returned string.
252 $netlist->resolve_filename(string, [lookup_type])
254 Convert a module name to a filename. Optional lookup_type is
255 'module', 'include', or 'all', to use only module_dirs, incdirs, or
256 both for the lookup. Return undef if not found.
257 $self->verilog_text
259 Returns verilog code which represents the netlist. The netlist
260 must be already ->link'ed for this to work correctly.
261
263 Cell instantiations without any arguments are not supported, a empty
264 set of parenthesis are required. (Use "cell cell();", not "cell
265 cell;".)
266 Order based pin interconnect is not supported, use name based
268 connections.
269
271 Verilog-Perl is part of the <https://www.veripool.org/> free Verilog
272 EDA software tool suite. The latest version is available from CPAN and
273 from <https://www.veripool.org/verilog-perl>.
274 Copyright 2000-2021 by Wilson Snyder. This package is free software;
276 you can redistribute it and/or modify it under the terms of either the
277 GNU Lesser General Public License Version 3 or the Perl Artistic
278 License Version 2.0.
279
281 Wilson Snyder <wsnyder@wsnyder.org>
282
284 Verilog-Perl, Verilog::Netlist::Cell, Verilog::Netlist::File,
285 Verilog::Netlist::Interface, Verilog::Netlist::Logger,
286 Verilog::Netlist::ModPort, Verilog::Netlist::Module,
287 Verilog::Netlist::Net, Verilog::Netlist::Pin,
288 Verilog::Netlist::PinSelection, Verilog::Netlist::Port,
289 Verilog::Netlist::Subclass
290 And the <https://www.veripool.org/verilog-mode>Verilog-Mode package for
292 Emacs.
293perl v5.34.0 2022-01-21 Netlist(3)