nv50/ir: Deal with graph iterators using RAII.

src/gallium/drivers/nv50/codegen/nv50_ir_bb.cpp

@@ -402,16 +402,14 @@ Function::setExit(BasicBlock *bb)
 unsigned int
 Function::orderInstructions(ArrayList &result)
 {
-   Iterator *iter;
-   for (iter = cfg.iteratorCFG(); !iter->end(); iter->next()) {
+   for (IteratorRef it = cfg.iteratorCFG(); !it->end(); it->next()) {
       BasicBlock *bb =
-         BasicBlock::get(reinterpret_cast<Graph::Node *>(iter->get()));
+         BasicBlock::get(reinterpret_cast<Graph::Node *>(it->get()));
 
       for (Instruction *insn = bb->getFirst(); insn; insn = insn->next)
          result.insert(insn, insn->serial);
    }
 
-   cfg.putIterator(iter);
    return result.getSize();
 }
 
@@ -466,7 +464,7 @@ Pass::run(Function *func, bool ordered, bool skipPhi)
 bool
 Pass::doRun(Function *func, bool ordered, bool skipPhi)
 {
-   Iterator *bbIter;
+   IteratorRef bbIter;
    BasicBlock *bb;
    Instruction *insn, *next;
 
@@ -487,7 +485,7 @@ Pass::doRun(Function *func, bool ordered, bool skipPhi)
             break;
       }
    }
-   func->cfg.putIterator(bbIter);
+
    return !err;
 }
 
@@ -503,10 +501,9 @@ Function::printCFGraph(const char *filePath)
 
    fprintf(out, "digraph G {\n");
 
-   Iterator *iter;
-   for (iter = cfg.iteratorDFS(); !iter->end(); iter->next()) {
+   for (IteratorRef it = cfg.iteratorDFS(); !it->end(); it->next()) {
       BasicBlock *bb = BasicBlock::get(
-         reinterpret_cast<Graph::Node *>(iter->get()));
+         reinterpret_cast<Graph::Node *>(it->get()));
       int idA = bb->getId();
       for (Graph::EdgeIterator ei = bb->cfg.outgoing(); !ei.end(); ei.next()) {
          int idB = BasicBlock::get(ei.getNode())->getId();
@@ -532,7 +529,6 @@ Function::printCFGraph(const char *filePath)
          }
       }
    }
-   cfg.putIterator(iter);
 
    fprintf(out, "}\n");
    fclose(out);

src/gallium/drivers/nv50/codegen/nv50_ir_graph.cpp

@@ -33,12 +33,8 @@ Graph::Graph()
 
 Graph::~Graph()
 {
-   Iterator *iter = this->safeIteratorDFS();
-
-   for (; !iter->end(); iter->next())
-      reinterpret_cast<Node *>(iter->get())->cut();
-
-   putIterator(iter);
+   for (IteratorRef it = safeIteratorDFS(); !it->end(); it->next())
+      reinterpret_cast<Node *>(it->get())->cut();
 }
 
 void Graph::insert(Node *node)
@@ -192,7 +188,7 @@ Graph::Node::reachableBy(Node *node, Node *term)
    return pos == this;
 }
 
-class DFSIterator : public Graph::GraphIterator
+class DFSIterator : public Iterator
 {
 public:
    DFSIterator(Graph *graph, const bool preorder)
@@ -241,17 +237,17 @@ protected:
    int pos;
 };
 
-Graph::GraphIterator *Graph::iteratorDFS(bool preorder)
+IteratorRef Graph::iteratorDFS(bool preorder)
 {
-   return new DFSIterator(this, preorder);
+   return IteratorRef(new DFSIterator(this, preorder));
 }
 
-Graph::GraphIterator *Graph::safeIteratorDFS(bool preorder)
+IteratorRef Graph::safeIteratorDFS(bool preorder)
 {
    return this->iteratorDFS(preorder);
 }
 
-class CFGIterator : public Graph::GraphIterator
+class CFGIterator : public Iterator
 {
 public:
    CFGIterator(Graph *graph)
@@ -262,10 +258,8 @@ public:
       nodes[graph->getSize()] = 0;
 
       // TODO: argh, use graph->sequence instead of tag and just raise it by > 1
-      Iterator *iter;
-      for (iter = graph->iteratorDFS(); !iter->end(); iter->next())
-         reinterpret_cast<Graph::Node *>(iter->get())->tag = 0;
-      graph->putIterator(iter);
+      for (IteratorRef it = graph->iteratorDFS(); !it->end(); it->next())
+         reinterpret_cast<Graph::Node *>(it->get())->tag = 0;
 
       if (graph->getRoot())
          search(graph->getRoot(), graph->nextSequence());
@@ -327,27 +321,25 @@ private:
    int pos;
 };
 
-Graph::GraphIterator *Graph::iteratorCFG()
+IteratorRef Graph::iteratorCFG()
 {
-   return new CFGIterator(this);
+   return IteratorRef(new CFGIterator(this));
 }
 
-Graph::GraphIterator *Graph::safeIteratorCFG()
+IteratorRef Graph::safeIteratorCFG()
 {
    return this->iteratorCFG();
 }
 
 void Graph::classifyEdges()
 {
-   DFSIterator *iter;
    int seq;
 
-   for (iter = new DFSIterator(this, true); !iter->end(); iter->next()) {
-      Node *node = reinterpret_cast<Node *>(iter->get());
+   for (IteratorRef it = iteratorDFS(true); !it->end(); it->next()) {
+      Node *node = reinterpret_cast<Node *>(it->get());
       node->visit(0);
       node->tag = 0;
    }
-   putIterator(iter);
 
    classifyDFS(root, (seq = 0));
 

src/gallium/drivers/nv50/codegen/nv50_ir_graph.h

@@ -36,12 +36,6 @@ class Graph
 public:
    class Node;
 
-   class GraphIterator : public Iterator
-   {
-   public:
-      virtual ~GraphIterator() { };
-   };
-
    class Edge
    {
    public:
@@ -162,14 +156,12 @@ public:
 
    void insert(Node *node); // attach to or set as root
 
-   GraphIterator *iteratorDFS(bool preorder = true);
-   GraphIterator *iteratorCFG();
+   IteratorRef iteratorDFS(bool preorder = true);
+   IteratorRef iteratorCFG();
 
    // safe iterators are unaffected by changes to the *edges* of the graph
-   GraphIterator *safeIteratorDFS(bool preorder = true);
-   GraphIterator *safeIteratorCFG();
-
-   inline void putIterator(Iterator *); // should be GraphIterator *
+   IteratorRef safeIteratorDFS(bool preorder = true);
+   IteratorRef safeIteratorCFG();
 
    void classifyEdges();
 
@@ -208,11 +200,6 @@ int Graph::Node::getSequence() const
    return visited;
 }
 
-void Graph::putIterator(Iterator *iter)
-{
-   delete reinterpret_cast<GraphIterator *>(iter);
-}
-
 Graph::EdgeIterator Graph::Node::outgoing(bool reverse) const
 {
    return EdgeIterator(out, 0, reverse);

src/gallium/drivers/nv50/codegen/nv50_ir_ssa.cpp

@@ -76,19 +76,17 @@ void DominatorTree::debugPrint()
 DominatorTree::DominatorTree(Graph *cfgraph) : cfg(cfgraph),
                                                count(cfg->getSize())
 {
-   Iterator *iter;
-   int i;
+   int i = 0;
 
    vert = new Node * [count];
    data = new int[5 * count];
 
-   for (i = 0, iter = cfg->iteratorDFS(true); !iter->end(); iter->next(), ++i) {
-      vert[i] = reinterpret_cast<Node *>(iter->get());
+   for (IteratorRef it = cfg->iteratorDFS(true); !it->end(); it->next(), ++i) {
+      vert[i] = reinterpret_cast<Node *>(it->get());
       vert[i]->tag = i;
       LABEL(i) = i;
       SEMI(i) = ANCESTOR(i) = -1;
    }
-   cfg->putIterator(iter);
 
    build();
 
@@ -190,33 +188,31 @@ void DominatorTree::build()
 
 void DominatorTree::findDominanceFrontiers()
 {
-   Iterator *dtIter;
    BasicBlock *bb;
 
-   for (dtIter = this->iteratorDFS(false); !dtIter->end(); dtIter->next()) {
-      EdgeIterator succIter, chldIter;
+   for (IteratorRef dtIt = iteratorDFS(false); !dtIt->end(); dtIt->next()) {
+      EdgeIterator succIt, chldIt;
 
-      bb = BasicBlock::get(reinterpret_cast<Node *>(dtIter->get()));
+      bb = BasicBlock::get(reinterpret_cast<Node *>(dtIt->get()));
       bb->getDF().clear();
 
-      for (succIter = bb->cfg.outgoing(); !succIter.end(); succIter.next()) {
-         BasicBlock *dfLocal = BasicBlock::get(succIter.getNode());
+      for (succIt = bb->cfg.outgoing(); !succIt.end(); succIt.next()) {
+         BasicBlock *dfLocal = BasicBlock::get(succIt.getNode());
          if (dfLocal->idom() != bb)
             bb->getDF().insert(dfLocal);
       }
 
-      for (chldIter = bb->dom.outgoing(); !chldIter.end(); chldIter.next()) {
-         BasicBlock *cb = BasicBlock::get(chldIter.getNode());
+      for (chldIt = bb->dom.outgoing(); !chldIt.end(); chldIt.next()) {
+         BasicBlock *cb = BasicBlock::get(chldIt.getNode());
 
-         DLList::Iterator dfIter = cb->getDF().iterator();
-         for (; !dfIter.end(); dfIter.next()) {
-            BasicBlock *dfUp = BasicBlock::get(dfIter);
+         DLList::Iterator dfIt = cb->getDF().iterator();
+         for (; !dfIt.end(); dfIt.next()) {
+            BasicBlock *dfUp = BasicBlock::get(dfIt);
             if (dfUp->idom() != bb)
                bb->getDF().insert(dfUp);
          }
       }
    }
-   this->putIterator(dtIter);
 }
 
 // liveIn(bb) = usedBeforeAssigned(bb) U (liveOut(bb) - assigned(bb))

src/gallium/drivers/nv50/codegen/nv50_ir_target.cpp

@@ -117,10 +117,8 @@ CodeEmitter::prepareEmission(Function *func)
 
    BasicBlock::get(func->cfg.getRoot())->binPos = func->binPos;
 
-   Graph::GraphIterator *iter;
-   for (iter = func->cfg.iteratorCFG(); !iter->end(); iter->next())
-      prepareEmission(BasicBlock::get(*iter));
-   func->cfg.putIterator(iter);
+   for (IteratorRef it = func->cfg.iteratorCFG(); !it->end(); it->next())
+      prepareEmission(BasicBlock::get(*it));
 }
 
 void

src/gallium/drivers/nv50/codegen/nv50_ir_util.h

@@ -27,6 +27,7 @@
 #include <assert.h>
 #include <stdio.h>
 #include <map>
+#include <memory>
 
 #ifndef NDEBUG
 # include <typeinfo>
@@ -86,11 +87,14 @@ namespace nv50_ir {
 class Iterator
 {
 public:
+   virtual ~Iterator() { };
    virtual void next() = 0;
    virtual void *get() const = 0;
    virtual bool end() const = 0; // if true, get will return 0
 };
 
+typedef std::auto_ptr<Iterator> IteratorRef;
+
 class ManipIterator : public Iterator
 {
 public: