1 #ifndef IVL_PGate_H
2 #define IVL_PGate_H
3 /*
4  * Copyright (c) 1998-2019 Stephen Williams (steve@icarus.com)
5  *
6  *    This source code is free software; you can redistribute it
7  *    and/or modify it in source code form under the terms of the GNU
8  *    General Public License as published by the Free Software
9  *    Foundation; either version 2 of the License, or (at your option)
10  *    any later version.
11  *
12  *    This program is distributed in the hope that it will be useful,
13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *    GNU General Public License for more details.
16  *
17  *    You should have received a copy of the GNU General Public License
18  *    along with this program; if not, write to the Free Software
19  *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20  */
21 
22 # include  "svector.h"
23 # include  "StringHeap.h"
24 # include  "named.h"
25 # include  "PNamedItem.h"
26 # include  "PDelays.h"
27 # include  "netlist.h"
28 # include  <map>
29 # include  <list>
30 # include  <vector>
31 # include  <string>
32 class PExpr;
33 class PUdp;
34 class Module;
35 
36 /*
37  * A PGate represents a Verilog gate. The gate has a name and other
38  * properties, and a set of pins that connect to wires. It is known at
39  * the time a gate is constructed how many pins the gate has.
40  *
41  * This pins of a gate are connected to expressions. The elaboration
42  * step will need to convert expressions to a network of gates in
43  * order to elaborate expression inputs, but that can easily be done.
44  *
45  * The PGate base class also carries the strength0 and strength1
46  * strengths for those gates where the driver[s] can be described by a
47  * single strength pair. There is a strength of the 0 drive, and a
48  * strength of the 1 drive.
49  */
50 class PGate : public PNamedItem {
51 
52     public:
53       explicit PGate(perm_string name, list<PExpr*>*pins,
54 		     const list<PExpr*>*del);
55 
56       explicit PGate(perm_string name, list<PExpr*>*pins,
57 		     PExpr*del);
58 
59       explicit PGate(perm_string name, list<PExpr*>*pins);
60 
61       virtual ~PGate();
62 
get_name()63       perm_string get_name() const { return name_; }
64 
65 	// This evaluates the delays as far as possible, but returns
66 	// an expression, and do not signal errors.
67       void eval_delays(Design*des, NetScope*scope,
68 		       NetExpr*&rise_time,
69 		       NetExpr*&fall_time,
70 		       NetExpr*&decay_time,
71 		       bool as_net_flag =false) const;
72 
73       unsigned delay_count() const;
74 
pin_count()75       unsigned pin_count() const { return pins_.size(); }
pin(unsigned idx)76       PExpr*pin(unsigned idx) const { return pins_[idx]; }
77 
78       ivl_drive_t strength0() const;
79       ivl_drive_t strength1() const;
80 
81       void strength0(ivl_drive_t);
82       void strength1(ivl_drive_t);
83 
84       map<perm_string,PExpr*> attributes;
85 
86       virtual void dump(ostream&out, unsigned ind =4) const;
87       virtual void elaborate(Design*des, NetScope*scope) const;
88       virtual void elaborate_scope(Design*des, NetScope*sc) const;
89       virtual bool elaborate_sig(Design*des, NetScope*scope) const;
90 
91       SymbolType symbol_type() const;
92 
93     protected:
get_pins()94       const vector<PExpr*>& get_pins() const { return pins_; }
95 
96       void dump_pins(ostream&out) const;
97       void dump_delays(ostream&out) const;
98 
99     private:
100       perm_string name_;
101       PDelays delay_;
102       vector<PExpr*>pins_;
103 
104       ivl_drive_t str0_, str1_;
105 
106       void set_pins_(list<PExpr*>*pins);
107 
108     private: // not implemented
109       PGate(const PGate&);
110       PGate& operator= (const PGate&);
111 };
112 
113 /* A continuous assignment has a single output and a single input. The
114    input is passed directly to the output. This is different from a
115    BUF because elaboration may need to turn this into a vector of
116    gates. */
117 class PGAssign  : public PGate {
118 
119     public:
120       explicit PGAssign(list<PExpr*>*pins);
121       explicit PGAssign(list<PExpr*>*pins, list<PExpr*>*dels);
122       ~PGAssign();
123 
124       void dump(ostream&out, unsigned ind =4) const;
125       virtual void elaborate(Design*des, NetScope*scope) const;
126       virtual bool elaborate_sig(Design*des, NetScope*scope) const;
127 
128     private:
129       void elaborate_unpacked_array_(Design*des, NetScope*scope, NetNet*lval) const;
130 };
131 
132 
133 /*
134  * The Builtin class is specifically a gate with one of the builtin
135  * types. The parser recognizes these types during parse. These types
136  * have special properties that allow them to be treated specially.
137  *
138  * A PGBuiltin can be grouped into an array of devices. If this is
139  * done, the msb_ and lsb_ are set to the indices of the array
140  * range. Elaboration causes a gate to be created for each element of
141  * the array, and a name will be generated for each gate.
142  */
143 class PGBuiltin  : public PGate {
144 
145     public:
146       enum Type { AND, NAND, OR, NOR, XOR, XNOR, BUF, BUFIF0, BUFIF1,
147 		  NOT, NOTIF0, NOTIF1, PULLDOWN, PULLUP, NMOS, RNMOS,
148 		  PMOS, RPMOS, CMOS, RCMOS, TRAN, RTRAN, TRANIF0,
149 		  TRANIF1, RTRANIF0, RTRANIF1 };
150 
151     public:
152       explicit PGBuiltin(Type t, perm_string name,
153 			 list<PExpr*>*pins,
154 			 list<PExpr*>*del);
155       explicit PGBuiltin(Type t, perm_string name,
156 			 list<PExpr*>*pins,
157 			 PExpr*del);
158       ~PGBuiltin();
159 
type()160       Type type() const { return type_; }
161       const char * gate_name() const;
162       void set_range(PExpr*msb, PExpr*lsb);
163 
164       virtual void dump(ostream&out, unsigned ind =4) const;
165       virtual void elaborate(Design*, NetScope*scope) const;
166       virtual bool elaborate_sig(Design*des, NetScope*scope) const;
167 
168     private:
169       unsigned calculate_array_count_(Design*, NetScope*,
170 				      long&high, long&low) const;
171 
172       void calculate_gate_and_lval_count_(unsigned&gate_count,
173                                           unsigned&lval_count) const;
174 
175       NetNode* create_gate_for_output_(Design*, NetScope*,
176 				       perm_string gate_name,
177 				       unsigned instance_width) const;
178 
179       bool check_delay_count(Design*des) const;
180 
181       Type type_;
182       PExpr*msb_;
183       PExpr*lsb_;
184 };
185 
186 /*
187  * This kind of gate is an instantiation of a module. The stored type
188  * is the name of a module definition somewhere in the pform. This
189  * type also handles UDP devices, because it is generally not known at
190  * parse time whether a name belongs to a module or a UDP.
191  */
192 class PGModule  : public PGate {
193 
194     public:
195 	// The name is the *instance* name of the gate.
196 
197 	// If the binding of ports is by position, this constructor
198 	// builds everything all at once.
199       explicit PGModule(perm_string type, perm_string name,
200 			list<PExpr*>*pins);
201 
202 	// If the binding of ports is by name, this constructor takes
203 	// the bindings and stores them for later elaboration.
204       explicit PGModule(perm_string type, perm_string name,
205 			named<PExpr*>*pins, unsigned npins);
206 
207 	// If the module type is known by design, then use this
208 	// constructor.
209       explicit PGModule(Module*type, perm_string name);
210 
211       ~PGModule();
212 
213 	// Parameter overrides can come as an ordered list, or a set
214 	// of named expressions.
215       void set_parameters(list<PExpr*>*o);
216       void set_parameters(named<PExpr*>*pa, unsigned npa);
217 
218 	// Modules can be instantiated in ranges. The parser uses this
219 	// method to pass the range to the pform.
220       void set_range(PExpr*msb, PExpr*lsb);
221 
222       map<perm_string,PExpr*> attributes;
223 
224       virtual void dump(ostream&out, unsigned ind =4) const;
225       virtual void elaborate(Design*, NetScope*scope) const;
226       virtual void elaborate_scope(Design*des, NetScope*sc) const;
227       virtual bool elaborate_sig(Design*des, NetScope*scope) const;
228 
229 	// This returns the module name of this module. It is a
230 	// permallocated string.
231       perm_string get_type() const;
232 
233     private:
234       Module*bound_type_;
235       perm_string type_;
236       list<PExpr*>*overrides_;
237       named<PExpr*>*pins_;
238       unsigned npins_;
239 
240 	// These members support parameter override by name
241       named<PExpr*>*parms_;
242       unsigned nparms_;
243 
244 	// Arrays of modules are give if these are set.
245       PExpr*msb_;
246       PExpr*lsb_;
247 
248       friend class delayed_elaborate_scope_mod_instances;
249       void elaborate_mod_(Design*, Module*mod, NetScope*scope) const;
250       void elaborate_udp_(Design*, PUdp  *udp, NetScope*scope) const;
251       unsigned calculate_instance_count_(Design*, NetScope*,
252                                          long&high, long&low,
253                                          perm_string name) const;
254       void elaborate_scope_mod_(Design*des, Module*mod, NetScope*sc) const;
255       void elaborate_scope_mod_instances_(Design*des, Module*mod, NetScope*sc) const;
256       bool elaborate_sig_mod_(Design*des, NetScope*scope, Module*mod) const;
257 	// Not currently used.
258 #if 0
259       bool elaborate_sig_udp_(Design*des, NetScope*scope, PUdp*udp) const;
260 #endif
261 
262       NetNet*resize_net_to_port_(Design*des, NetScope*scope,
263 				 NetNet*sig, unsigned port_wid,
264 				 NetNet::PortType dir, bool as_signed) const;
265 };
266 
267 #endif /* IVL_PGate_H */
268