finish preparations for coloring

src/opt/confgraph.cpp

@@ -1,6 +1,80 @@
 #include "confgraph.h"
+#include <cstdint>
+#include <set>
+#include <string>
 #include <unordered_map>
+#include <unordered_set>
 #include "cfg.h"
+ConfGraph BuildConfGraph(CFGType &cfg) {
+  std::unordered_map<ConfGraphNode *, std::unordered_set<ConfGraphNode *>> edges;
+  ConfGraph res;
+  for (size_t id = 0; id < cfg.id_to_var.size(); id++) {
+    auto node = std::make_shared<ConfGraphNode>();
+    node->var_ids.push_back(id);
+    res.id_to_node[id] = node.get();
+    res.nodes.push_back(node);
+    node->is_binded_with_physical_reg = false;
+  }
+  for (auto cfg_node : cfg.nodes) {
+    for (const auto &[act, out_active] : cfg_node->action_out_active_vars) {
+      const auto &def_vars = cfg_node->action_def_vars[act];
+      for (auto def_var : def_vars) {
+        for (auto out_var : out_active) {
+          edges[res.id_to_node[def_var]].insert(res.id_to_node[out_var]);
+          edges[res.id_to_node[out_var]].insert(res.id_to_node[def_var]);
+        }
+      }
+    }
+  }
+  for (const auto &[u, neighbors] : edges) {
+    for (auto v : neighbors) {
+      u->neighbors.push_back(v);
+      res.adj_table[u][v] = std::prev(u->neighbors.end());
+    }
+    u->neighbors.sort();
+  }
+  for (auto node : res.nodes) {
+    node->degree = node->neighbors.size();
+  }
+  for (auto reg : allocating_regs) {
+    size_t reg_id = cfg.var_to_id["%reg." + reg];
+    res.id_to_node[reg_id]->is_binded_with_physical_reg = true;
+    res.id_to_node[reg_id]->color = std::stoi(reg.substr(1));
+    res.id_to_node[reg_id]->degree = ConfGraphNode::kInf;
+  }
+  return res;
+}
+const static size_t kMaxRegs = allocating_regs.size();
+void InitializeBeforeColoring(std::shared_ptr<FunctionDefItem> src, CFGType &cfg, ConfGraph &confgraph) {
+  confgraph.stack.clear();
+  confgraph.actual_spills.clear();
 
-ConfGraph BuildConfGraph(CFGType &cfg) { ; }
-bool TryColoring(std::shared_ptr<FunctionDefItem> src, CFGType &cfg, ConfGraph& confgraph) { return false; }
+  confgraph.low_degree_and_not_move_related.clear();
+  confgraph.low_degree_and_move_related.clear();
+  confgraph.high_degree_nodes.clear();  // note that physical registers are not included in this set
+
+  confgraph.pending_moves.clear();
+  confgraph.potential_moves.clear();
+}
+bool ConductColoring(std::shared_ptr<FunctionDefItem> src, CFGType &cfg, ConfGraph &confgraph) {
+  InitializeBeforeColoring(src, cfg, confgraph);
+  do {
+    if (confgraph.low_degree_and_not_move_related.size() > 0) {
+      // simplify
+    } else if (confgraph.pending_moves.size() > 0) {
+      // coalesce
+    } else if (confgraph.low_degree_and_move_related.size() > 0) {
+      // freeze
+    } else if (confgraph.high_degree_nodes.size() > 0) {
+      // potential spill
+    }
+  } while (confgraph.low_degree_and_not_move_related.size() > 0 || confgraph.pending_moves.size() > 0 ||
+           confgraph.low_degree_and_move_related.size() > 0 || confgraph.high_degree_nodes.size() > 0);
+  // select and spill
+  if (confgraph.actual_spills.size() > 0) {
+    std::cerr << "spilled " << confgraph.actual_spills.size() << " nodes" << std::endl;
+    // allocate memory for spilled nodes
+    return true;
+  }
+  return false;
+}