Merge branch 'github/Blif', fast blif parser.

crlcore/src/ccore/blif/BlifParser.cpp

@@ -105,15 +105,38 @@ namespace {
     string name;
     unordered_map<string, Net::Direction> pins;
     vector<subckt> subcircuits;
+    vector<pair<string, string> > aliases;
     bool operator<(model const & o) const{ return name < o.name; }
   };
 
+  std::vector<std::string> tokenize(std::string const & s){
+    std::vector<std::string> ret;
+    auto b_it = s.begin();
+    while(b_it != s.end()){
+      // Remove whitespace
+      while(b_it != s.end() && (*b_it == ' ' or *b_it == '\t'))
+        ++b_it;
+      // Find the end of the token
+      auto e_it = b_it;
+      while(e_it != s.end() && *e_it != ' ' && *e_it != '\t' and *e_it != '#')
+        ++e_it;
+      // Create the token
+      if(e_it != b_it)
+        ret.push_back(std::string(b_it, e_it));
+      // Handle comments
+      if(e_it != s.end() && *e_it == '#')
+        e_it = s.end();
+      b_it = e_it;
+    }
+    std::reverse(ret.begin(), ret.end());
+    return ret;
+  }
+
 }  // End of anonymous namespace.
 
 
 namespace CRL {
 
-
 // 
 // Can only parse simple, netlist BLIF files generated by Yosys
 // Ignores all ".names" and uses only the .subckt, .model, .input and .output 
@@ -136,15 +159,35 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
   bool hasName;
 
   string line;
+  vector<string> current_names;
   while(getline(ccell, line)){
     istringstream linestream(line);
-    string before_comment;
+    vector<string> tokens = tokenize(line);
-    getline(linestream, before_comment, '#');
+    if(not tokens.empty()){
-    istringstream tokens(before_comment);
+      string const token = tokens.back();
-    string token;
+      tokens.pop_back();
-    while(tokens>>token){
       assert(not token.empty());
       if(token[0] == '.'){
+        // Process finished .names statement
+        if(not current_names.empty()){
+          if( current_names.size() != 4
+            or current_names[2] != "1" or current_names[3] != "1"
+            ){
+            ostringstream mess;
+            mess << ".names statement is not an alias and will be ignored "
+                 << "(map to standard cells for functions and tie cells for constants)\n";
+            for(string const & S: current_names){
+                mess << S << " ";
+            }
+            mess << "\n";
+            cerr << Warning(mess.str());
+          }
+          else{
+            // Name statement is an alias: the second signal will map to the first
+            models.back().aliases.push_back(pair<string, string>(current_names[0], current_names[1]));
+          }
+          current_names.clear();
+        }
         if(token == ".model"){
           if(state != EXT)
             throw Error("Nested model are not supported\n");
@@ -162,13 +205,11 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
           models.back().subcircuits.push_back(subckt());
         }
         else if(token == ".names"){
-          cerr << Warning("BLIF names are ignored\n");
           if(state == EXT)
             throw Error("Names without an enclosing model are not supported\n");
           if(state == MODEL and not hasName)
             throw Error("Model has no name\n");
           state = NAMES;
-          hasName = false;
         }
         else if(token == ".latch"){
           throw Error("Latch constructs are not understood by the parser\n");
@@ -189,10 +230,28 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
           state = EXT;
         }
         else{
-          throw Error("Unexpected control token\n");
+          ostringstream mess;
+          mess << "Unknown control token <" << token << ">\n";
+          throw Error(mess.str());
+        }
+
+      }
+      else if(state == NAMES){
+        // Part of a cover for a logic function
+        current_names.push_back(token);
+      }
+      else{
+        ostringstream mess;
+        mess << "Encountered a non-control token at the beginning of a line: <" << token << ">\n";
+        throw Error(mess.str());
       }
     }
-      else{ // Either a pin or an input/output definition
+    // Process all tokens after the control
+    while(not tokens.empty()){
+      string const token = tokens.back();
+      tokens.pop_back();
+      assert(not token.empty());
+      // Either a pin or an input/output definition
       if(state == INPUTS or state == OUTPUTS){
         auto it = models.back().pins.find(token);
         Net::Direction D = (state == INPUTS)? Net::Direction::DirIn : Net::Direction::DirOut;
@@ -206,28 +265,33 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
       else if(state == SUBCKT){
         if(hasName){
           // Encountered a pin: need to be processed
-            istringstream token_stream(token);
+          auto equal_pos = token.find_first_of('=');
-            string before_space, after_space;
+          if(equal_pos+1 < token.size()){
-            getline(token_stream, before_space, '=');
+            string before_space = token.substr(0, equal_pos);
-            getline(token_stream, after_space, '=');
+            string after_space  = token.substr(equal_pos+1, string::npos);
-            if(token_stream){
-                Error("Encountered more than one '=' in token");
-            }
             models.back().subcircuits.back().pins.push_back(pair<string, string>(before_space, after_space));
           }
+          else{
+            ostringstream mess;
+            mess << "Unable to parse the subckt pin specification <"
+                 << token << ">\n";
+            Error(mess.str());
+          }
+        }
         else{
           models.back().subcircuits.back().cell = token;
           hasName = true;
         }
       }
       else if(state == NAMES){
-            // TODO; now just ignored
+          current_names.push_back(token);
       }
       else if(state == MODEL){
         if(hasName)
           throw Error("Unexpected token after model name\n");
         else{
           models.back().name = token;
+          cmess2 << "Processing model <" << token << ">" << endl;
           hasName = true;
         }
       }
@@ -235,7 +299,6 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
         throw Error("Unexpected token\n");
       }
     }
-    }
     line.clear();
   }
   if(state != EXT){
@@ -255,13 +318,14 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
   }
   */
 
-  if(models.size() > 1){
+  // Two passes: first create the cells and their nets, then create the internals
-    cerr << Warning("Several models in the file; only the last was open\n");
+  std::vector<Cell*> model_cells;
-  }
-
-  Cell * design = NULL;
   for(auto M : models){
-    design = framework->createCell(M.name);
+    Cell * design = framework->createCell(M.name);
+    if(design == NULL){
+      throw Error("Model " + M.name + " is NULL\n");
+    }
+    model_cells.push_back(design);
     addSupplyNets(design);
 
     unordered_set<string> net_names;
@@ -269,6 +333,10 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
       for(auto const & P : S.pins){
         net_names.insert(P.second);
       }
+      for(auto const & A : M.aliases){
+        net_names.insert(A.first);
+        net_names.insert(A.second);
+      }
     }
     for(auto const & P : M.pins){
       net_names.insert(P.first);
@@ -282,30 +350,60 @@ Cell * Blif::load ( string cellPath ) //, Cell *cell )
         new_net->setDirection( it->second );
       }
     }
-
+  }
-    int i=0;
+  // Second pass: every cell and its nets have already been created
-    for(auto & S : M.subcircuits){
+  for(int i=0; i<models.size(); ++i){
+    cmess2 << "Handling model " << models[i].name << endl;
+    auto const & M = models[i];
+    Cell * design = model_cells[i];
+    for(int j=0; j<M.subcircuits.size(); ++j){
+      auto & S = M.subcircuits[j];
       ostringstream subckt_name;
-      subckt_name << "subckt_" << i;
+      subckt_name << "subckt_" << j;
       Cell * cell = framework->getCell(S.cell, Catalog::State::Views, 0);
       if(cell == NULL){
-        cerr << Warning("Cell " + S.cell + "to instanciate hasn't been found\n");
+        throw Error("Cell <" + S.cell + "> to instanciate hasn't been found\n");
-        continue;
       }
+      //cmess2 << "Creating instance <" << subckt_name.str() << "> of <" << S.cell << "> in <" << models[i].name << ">" << endl;
       Instance* instance = Instance::create( design, subckt_name.str(), cell);
 
       for(auto & P : S.pins){
         Net* internalNet = cell->getNet( P.first );
         Net* externalNet = design->getNet( P.second );
-        assert(internalNet != NULL and externalNet != NULL);
+        assert(internalNet != NULL and externalNet != NULL and instance != NULL);
         instance->getPlug( internalNet )->setNet( externalNet );
       }
       //connectSupplyNets(instance, design);
-      ++i;
+    }
+    // Merge the aliased nets
+    for(auto alias : M.aliases){
+      //cmess2 << "Merging nets <" << alias.first << "> and <" << alias.second << ">" << endl;
+      Net * first_net  = design->getNet( alias.first );
+      Net * second_net = design->getNet( alias.second );
+      if(first_net == NULL or second_net == NULL){
+        ostringstream mess;
+        mess << "Trying to create an alias for non-instantiated nets:";
+        if(first_net == NULL)
+          mess << " <" << alias.first << ">";
+        if(second_net == NULL)
+          mess << " <" << alias.second << ">";
+        mess << ", will be ignored\n";
+        cerr << Warning(mess.str());
+        continue;
+      }
+      if(!first_net->isExternal())
+          swap(first_net, second_net); // If only one net is external, it needs to be the first
+      first_net->merge(second_net);
     }
   }
-
+  cmess2 << "BLIF file loaded" << endl;
-  return design;
+  if(model_cells.empty()){
+    throw Error("No model found in the file\n");
+  }
+  else if(model_cells.size() > 1){
+    cerr << Warning("Several models found: returned the first one\n");
+  }
+  return model_cells[0];
 }
 
 }