rtlil: Make Process handling more uniform with Cell and Wire.

- add a backlink to module from Process
- make constructor and destructor protected, expose Module functions
  to add and remove processes

frontends/ast/genrtlil.cc

@@ -319,16 +319,14 @@ struct AST_INTERNAL::ProcessGenerator
 		LookaheadRewriter la_rewriter(always);
 
 		// generate process and simple root case
-		proc = new RTLIL::Process;
+		proc = current_module->addProcess(stringf("$proc$%s:%d$%d", always->filename.c_str(), always->location.first_line, autoidx++));
 		set_src_attr(proc, always);
-		proc->name = stringf("$proc$%s:%d$%d", always->filename.c_str(), always->location.first_line, autoidx++);
 		for (auto &attr : always->attributes) {
 			if (attr.second->type != AST_CONSTANT)
 				log_file_error(always->filename, always->location.first_line, "Attribute `%s' with non-constant value!\n",
 						attr.first.c_str());
 			proc->attributes[attr.first] = attr.second->asAttrConst();
 		}
-		current_module->processes[proc->name] = proc;
 		current_case = &proc->root_case;
 
 		// create initial temporary signal for all output registers

frontends/rtlil/rtlil_parser.y

@@ -283,10 +283,8 @@ proc_stmt:
 	TOK_PROCESS TOK_ID EOL {
 		if (current_module->processes.count($2) != 0)
 			rtlil_frontend_yyerror(stringf("RTLIL error: redefinition of process %s.", $2).c_str());
-		current_process = new RTLIL::Process;
-		current_process->name = $2;
+		current_process = current_module->addProcess($2);
 		current_process->attributes = attrbuf;
-		current_module->processes[$2] = current_process;
 		switch_stack.clear();
 		switch_stack.push_back(&current_process->root_case.switches);
 		case_stack.clear();

kernel/rtlil.cc

@@ -1839,6 +1839,14 @@ void RTLIL::Module::add(RTLIL::Cell *cell)
 	cell->module = this;
 }
 
+void RTLIL::Module::add(RTLIL::Process *process)
+{
+	log_assert(!process->name.empty());
+	log_assert(count_id(process->name) == 0);
+	processes[process->name] = process;
+	process->module = this;
+}
+
 void RTLIL::Module::remove(const pool<RTLIL::Wire*> &wires)
 {
 	log_assert(refcount_wires_ == 0);
@@ -1895,6 +1903,13 @@ void RTLIL::Module::remove(RTLIL::Cell *cell)
 	delete cell;
 }
 
+void RTLIL::Module::remove(RTLIL::Process *process)
+{
+	log_assert(processes.count(process->name) != 0);
+	processes.erase(process->name);
+	delete process;
+}
+
 void RTLIL::Module::rename(RTLIL::Wire *wire, RTLIL::IdString new_name)
 {
 	log_assert(wires_[wire->name] == wire);
@@ -2120,11 +2135,19 @@ RTLIL::Memory *RTLIL::Module::addMemory(RTLIL::IdString name, const RTLIL::Memor
 	return mem;
 }
 
+RTLIL::Process *RTLIL::Module::addProcess(RTLIL::IdString name)
+{
+	RTLIL::Process *proc = new RTLIL::Process;
+	proc->name = name;
+	add(proc);
+	return proc;
+}
+
 RTLIL::Process *RTLIL::Module::addProcess(RTLIL::IdString name, const RTLIL::Process *other)
 {
 	RTLIL::Process *proc = other->clone();
 	proc->name = name;
-	processes[name] = proc;
+	add(proc);
 	return proc;
 }
 
@@ -2920,6 +2943,13 @@ RTLIL::Memory::Memory()
 #endif
 }
 
+RTLIL::Process::Process() : module(nullptr)
+{
+	static unsigned int hashidx_count = 123456789;
+	hashidx_count = mkhash_xorshift(hashidx_count);
+	hashidx_ = hashidx_count;
+}
+
 RTLIL::Cell::Cell() : module(nullptr)
 {
 	static unsigned int hashidx_count = 123456789;

kernel/rtlil.h

@@ -1129,6 +1129,7 @@ struct RTLIL::Module : public RTLIL::AttrObject
 protected:
 	void add(RTLIL::Wire *wire);
 	void add(RTLIL::Cell *cell);
+	void add(RTLIL::Process *process);
 
 public:
 	RTLIL::Design *design;
@@ -1209,6 +1210,7 @@ public:
 	// Removing wires is expensive. If you have to remove wires, remove them all at once.
 	void remove(const pool<RTLIL::Wire*> &wires);
 	void remove(RTLIL::Cell *cell);
+	void remove(RTLIL::Process *process);
 
 	void rename(RTLIL::Wire *wire, RTLIL::IdString new_name);
 	void rename(RTLIL::Cell *cell, RTLIL::IdString new_name);
@@ -1228,6 +1230,7 @@ public:
 
 	RTLIL::Memory *addMemory(RTLIL::IdString name, const RTLIL::Memory *other);
 
+	RTLIL::Process *addProcess(RTLIL::IdString name);
 	RTLIL::Process *addProcess(RTLIL::IdString name, const RTLIL::Process *other);
 
 	// The add* methods create a cell and return the created cell. All signals must exist in advance.
@@ -1581,12 +1584,21 @@ struct RTLIL::SyncRule
 
 struct RTLIL::Process : public RTLIL::AttrObject
 {
+	unsigned int hashidx_;
+	unsigned int hash() const { return hashidx_; }
+
+protected:
+	// use module->addProcess() and module->remove() to create or destroy processes
+	friend struct RTLIL::Module;
+	Process();
+	~Process();
+
+public:
 	RTLIL::IdString name;
+	RTLIL::Module *module;
 	RTLIL::CaseRule root_case;
 	std::vector<RTLIL::SyncRule*> syncs;
 
-	~Process();
-
 	template<typename T> void rewrite_sigspecs(T &functor);
 	template<typename T> void rewrite_sigspecs2(T &functor);
 	RTLIL::Process *clone() const;

kernel/yosys.h

@@ -222,6 +222,7 @@ namespace RTLIL {
 	struct Wire;
 	struct Cell;
 	struct Memory;
+	struct Process;
 	struct Module;
 	struct Design;
 	struct Monitor;
@@ -245,6 +246,7 @@ namespace hashlib {
 	template<> struct hash_ops<RTLIL::Wire*> : hash_obj_ops {};
 	template<> struct hash_ops<RTLIL::Cell*> : hash_obj_ops {};
 	template<> struct hash_ops<RTLIL::Memory*> : hash_obj_ops {};
+	template<> struct hash_ops<RTLIL::Process*> : hash_obj_ops {};
 	template<> struct hash_ops<RTLIL::Module*> : hash_obj_ops {};
 	template<> struct hash_ops<RTLIL::Design*> : hash_obj_ops {};
 	template<> struct hash_ops<RTLIL::Monitor*> : hash_obj_ops {};
@@ -253,6 +255,7 @@ namespace hashlib {
 	template<> struct hash_ops<const RTLIL::Wire*> : hash_obj_ops {};
 	template<> struct hash_ops<const RTLIL::Cell*> : hash_obj_ops {};
 	template<> struct hash_ops<const RTLIL::Memory*> : hash_obj_ops {};
+	template<> struct hash_ops<const RTLIL::Process*> : hash_obj_ops {};
 	template<> struct hash_ops<const RTLIL::Module*> : hash_obj_ops {};
 	template<> struct hash_ops<const RTLIL::Design*> : hash_obj_ops {};
 	template<> struct hash_ops<const RTLIL::Monitor*> : hash_obj_ops {};

passes/cmds/bugpoint.cc

@@ -275,7 +275,7 @@ struct BugpointPass : public Pass {
 				if (mod->get_blackbox_attribute())
 					continue;
 
-				RTLIL::IdString removed_process;
+				RTLIL::Process *removed_process = nullptr;
 				for (auto process : mod->processes)
 				{
 					if (process.second->get_bool_attribute(ID::bugpoint_keep))
@@ -284,13 +284,12 @@ struct BugpointPass : public Pass {
 					if (index++ == seed)
 					{
 						log_header(design, "Trying to remove process %s.%s.\n", log_id(mod), log_id(process.first));
-						removed_process = process.first;
+						removed_process = process.second;
 						break;
 					}
 				}
-				if (!removed_process.empty()) {
-					delete mod->processes[removed_process];
-					mod->processes.erase(removed_process);
+				if (removed_process) {
+					mod->remove(removed_process);
 					return design_copy;
 				}
 			}

passes/cmds/delete.cc

@@ -90,7 +90,7 @@ struct DeletePass : public Pass {
 
 			pool<RTLIL::Wire*> delete_wires;
 			pool<RTLIL::Cell*> delete_cells;
-			pool<RTLIL::IdString> delete_procs;
+			pool<RTLIL::Process*> delete_procs;
 			pool<RTLIL::IdString> delete_mems;
 
 			for (auto wire : module->selected_wires())
@@ -110,7 +110,7 @@ struct DeletePass : public Pass {
 
 			for (auto &it : module->processes)
 				if (design->selected(module, it.second))
-					delete_procs.insert(it.first);
+					delete_procs.insert(it.second);
 
 			for (auto &it : delete_mems) {
 				delete module->memories.at(it);
@@ -120,10 +120,8 @@ struct DeletePass : public Pass {
 			for (auto &it : delete_cells)
 				module->remove(it);
 
-			for (auto &it : delete_procs) {
-				delete module->processes.at(it);
-				module->processes.erase(it);
-			}
+			for (auto &it : delete_procs)
+				module->remove(it);
 
 			module->remove(delete_wires);
 

passes/proc/proc_clean.cc

@@ -209,7 +209,7 @@ struct ProcCleanPass : public Pass {
 		extra_args(args, argidx, design);
 
 		for (auto mod : design->modules()) {
-			std::vector<RTLIL::IdString> delme;
+			std::vector<RTLIL::Process *> delme;
 			if (!design->selected(mod))
 				continue;
 			for (auto &proc_it : mod->processes) {
@@ -220,12 +220,11 @@ struct ProcCleanPass : public Pass {
 						proc_it.second->root_case.actions.size() == 0) {
 					if (!quiet)
 						log("Removing empty process `%s.%s'.\n", log_id(mod), proc_it.second->name.c_str());
-					delme.push_back(proc_it.first);
+					delme.push_back(proc_it.second);
 				}
 			}
-			for (auto &id : delme) {
-				delete mod->processes[id];
-				mod->processes.erase(id);
+			for (auto proc : delme) {
+				mod->remove(proc);
 			}
 		}