fixup! Add ControlFlowGraph and implementation

Author: jgardn3r

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphBuilder.java

@@ -18,13 +18,11 @@
  */
 package au.com.integradev.delphi.cfg;
 
-import static au.com.integradev.delphi.cfg.block.ProtoBlockBuilder.newBlock;
-
 import au.com.integradev.delphi.cfg.api.Block;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
 import au.com.integradev.delphi.cfg.block.BlockImpl;
 import au.com.integradev.delphi.cfg.block.ProtoBlock;
-import au.com.integradev.delphi.cfg.block.ProtoBlockBuilder;
+import au.com.integradev.delphi.cfg.block.ProtoBlockFactory;
 import com.google.common.collect.Lists;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
@@ -57,7 +55,8 @@ public class ControlFlowGraphBuilder {
   private final Deque<TryContext> tryContexts = new ArrayDeque<>();
 
   public ControlFlowGraphBuilder() {
-    ProtoBlock exitBlock = addBlock(newBlock());
+    ProtoBlock exitBlock = ProtoBlockFactory.exitBlock();
+    addBlock(exitBlock);
     exitBlocks.add(exitBlock);
     addBlockBefore(exitBlock);
   }
@@ -145,15 +144,15 @@ public void addLabel(LabelStatementNode labelNode) {
     // When "resolving" label, all the previously unresolved targets must be updated
     for (UnresolvedLabel unresolvedLabel : unresolvedLabels.get(label)) {
       unresolvedLabel.block.update(
-          newBlock().withJump(unresolvedLabel.node, currentBlock, unresolvedLabel.nextBlock));
+          ProtoBlockFactory.jump(unresolvedLabel.node, currentBlock, unresolvedLabel.nextBlock));
     }
   }
 
   public void addGoto(GotoStatementNode gotoNode) {
     NameReferenceNode labelNode = gotoNode.getNameReference();
     String label = labelNode.getImage();
     if (labelTargets.containsKey(label)) {
-      addBlock(newBlock().withJump(gotoNode, labelTargets.get(label), currentBlock));
+      addBlock(ProtoBlockFactory.jump(gotoNode, labelTargets.get(label), currentBlock));
       return;
     }
 
@@ -236,17 +235,16 @@ public void addElement(DelphiNode element) {
   }
 
   public ProtoBlock addBlockBeforeCurrent() {
-    return addBlockBefore(currentBlock);
+    addBlockBefore(currentBlock);
+    return currentBlock;
   }
 
-  public ProtoBlock addBlockBefore(ProtoBlock successor) {
-    return addBlock(newBlock().withSuccessor(successor));
+  public void addBlockBefore(ProtoBlock successor) {
+    addBlock(ProtoBlockFactory.succeedingTo(successor));
   }
 
-  public ProtoBlock addBlock(ProtoBlockBuilder builder) {
-    ProtoBlock result = builder.build();
-    blocks.add(result);
-    currentBlock = result;
-    return result;
+  public void addBlock(ProtoBlock block) {
+    blocks.add(block);
+    currentBlock = block;
   }
 }

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphImpl.java

@@ -75,8 +75,6 @@ public void prune() {
 
       blocks.forEach(inactiveBlocks::remove);
     } while (!inactiveBlocks.isEmpty());
-
-    return this;
   }
 
   private boolean isInactive(Block block) {

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphVisitor.java

@@ -18,10 +18,9 @@
  */
 package au.com.integradev.delphi.cfg;
 
-import static au.com.integradev.delphi.cfg.block.ProtoBlockBuilder.newBlock;
-
 import au.com.integradev.delphi.antlr.ast.visitors.DelphiParserVisitor;
 import au.com.integradev.delphi.cfg.block.ProtoBlock;
+import au.com.integradev.delphi.cfg.block.ProtoBlockFactory;
 import java.util.AbstractMap.SimpleEntry;
 import java.util.ArrayList;
 import java.util.HashSet;
@@ -153,12 +152,12 @@ public ControlFlowGraphBuilder visit(NameReferenceNode node, ControlFlowGraphBui
     switch (routineName) {
       case "System.Exit":
         builder.addBlock(
-            newBlock().withJump(node, builder.getExitBlock(), builder.getCurrentBlock()));
+            ProtoBlockFactory.jump(node, builder.getExitBlock(), builder.getCurrentBlock()));
         return builder;
       case "System.Break":
         return buildControlFlowStatement(node, builder.getBreakTarget(), builder);
       case "System.Halt":
-        builder.addBlock(newBlock().withProgramTerminator(node));
+        builder.addBlock(ProtoBlockFactory.halt(node));
         return builder;
       case "System.Continue":
         return buildControlFlowStatement(node, builder.getContinueTarget(), builder);
@@ -177,7 +176,7 @@ private static ControlFlowGraphBuilder buildControlFlowStatement(
       throw new IllegalStateException(
           String.format("'%s' statement not in loop statement", node.getImage()));
     }
-    builder.addBlock(newBlock().withJump(node, target, builder.getCurrentBlock()));
+    builder.addBlock(ProtoBlockFactory.jump(node, target, builder.getCurrentBlock()));
     return builder;
   }
 
@@ -188,7 +187,7 @@ private static void handleExceptionalPaths(ControlFlowGraphBuilder builder) {
     }
 
     Set<ProtoBlock> exceptions = builder.getAllCatchTargets();
-    builder.addBlock(newBlock().withExceptions(builder.getCurrentBlock(), exceptions));
+    builder.addBlock(ProtoBlockFactory.withExceptions(builder.getCurrentBlock(), exceptions));
   }
 
   /** Overridden to ensure {@code NodeDeclaration}s are added in the correct order */
@@ -247,23 +246,17 @@ public ControlFlowGraphBuilder visit(IfStatementNode node, ControlFlowGraphBuild
     ProtoBlock after = builder.getCurrentBlock();
 
     // process `else`
-    ProtoBlock elseBlock = after;
-    if (node.getElseStatement() != null) {
-      StatementNode elseStatement = node.getElseStatement();
-      if (!(elseStatement instanceof IfStatementNode)) {
-        builder.addBlockBefore(after);
-      }
-      elseStatement.accept(this, builder);
-      elseBlock = builder.getCurrentBlock();
-    }
+    builder.addBlockBefore(after);
+    build(node.getElseStatement(), builder);
+    ProtoBlock elseBlock = builder.getCurrentBlock();
 
     // process `then`
     builder.addBlockBefore(after);
     build(node.getThenStatement(), builder);
     ProtoBlock thenBlock = builder.getCurrentBlock();
 
     // process condition
-    builder.addBlock(newBlock().withBranch(node, thenBlock, elseBlock));
+    builder.addBlock(ProtoBlockFactory.withBranch(node, thenBlock, elseBlock));
     return buildCondition(builder, node.getGuardExpression(), thenBlock, elseBlock);
   }
 
@@ -295,7 +288,7 @@ private ControlFlowGraphBuilder buildConditionAnd(
     buildCondition(builder, node.getRight(), trueBlock, falseBlock);
     ProtoBlock newTrueBlock = builder.getCurrentBlock();
     // LHS
-    builder.addBlock(newBlock().withBranch(node, newTrueBlock, falseBlock));
+    builder.addBlock(ProtoBlockFactory.withBranch(node, newTrueBlock, falseBlock));
     return buildCondition(builder, node.getLeft(), newTrueBlock, falseBlock);
   }
 
@@ -308,7 +301,7 @@ private ControlFlowGraphBuilder buildConditionOr(
     buildCondition(builder, node.getRight(), trueBlock, falseBlock);
     ProtoBlock newFalseBlock = builder.getCurrentBlock();
     // LHS
-    builder.addBlock(newBlock().withBranch(node, trueBlock, newFalseBlock));
+    builder.addBlock(ProtoBlockFactory.withBranch(node, trueBlock, newFalseBlock));
     return buildCondition(builder, node.getLeft(), trueBlock, newFalseBlock);
   }
 
@@ -382,7 +375,7 @@ public ControlFlowGraphBuilder visit(CaseStatementNode node, ControlFlowGraphBui
       caseSuccessors.add(builder.getCurrentBlock());
     }
 
-    caseBlock.update(newBlock().withCases(node, caseSuccessors));
+    caseBlock.update(ProtoBlockFactory.cases(node, caseSuccessors));
     builder.setCurrentBlock(conditionBlock);
     return builder;
   }
@@ -408,20 +401,20 @@ public ControlFlowGraphBuilder visit(CaseStatementNode node, ControlFlowGraphBui
   @Override
   public ControlFlowGraphBuilder visit(RepeatStatementNode node, ControlFlowGraphBuilder builder) {
     ProtoBlock after = builder.getCurrentBlock();
-    // Create a placeholder for the conditional block
-    ProtoBlock loopback = builder.addBlockBefore(after);
+    // Create a placeholder for the body's starting block
+    ProtoBlock body = builder.addBlockBeforeCurrent();
 
     // Condition
-    builder.addBlock(newBlock().withBranch(node, after, loopback));
-    buildCondition(builder, node.getGuardExpression(), after, loopback);
+    builder.addBlock(ProtoBlockFactory.withBranch(node, after, body));
+    buildCondition(builder, node.getGuardExpression(), after, body);
 
     // Body
     builder.pushLoopContext(builder.getCurrentBlock(), after);
     builder.addBlockBeforeCurrent();
     build(node.getStatementList(), builder);
     builder.popLoopContext();
 
-    loopback.update(newBlock().withSuccessor(builder.getCurrentBlock()));
+    body.update(ProtoBlockFactory.succeedingTo(builder.getCurrentBlock()));
     builder.addBlockBeforeCurrent();
     return builder;
   }
@@ -446,21 +439,22 @@ public ControlFlowGraphBuilder visit(RepeatStatementNode node, ControlFlowGraphB
   @Override
   public ControlFlowGraphBuilder visit(WhileStatementNode node, ControlFlowGraphBuilder builder) {
     ProtoBlock after = builder.getCurrentBlock();
-    // Create a placeholder for the conditional block
-    ProtoBlock loopback = builder.addBlockBefore(after);
+    // Create a placeholder for the condition's starting block
+    ProtoBlock condition = builder.addBlockBeforeCurrent();
 
     // Body
-    builder.addBlockBefore(loopback);
-    builder.pushLoopContext(loopback, after);
+    builder.addBlockBefore(condition);
+    builder.pushLoopContext(condition, after);
     build(node.getStatement(), builder);
     builder.popLoopContext();
     ProtoBlock body = builder.getCurrentBlock();
 
     // Condition
-    builder.addBlock(newBlock().withBranch(node, body, after));
+    builder.setCurrentBlock(condition);
+    builder.addBlock(ProtoBlockFactory.withBranch(node, body, after));
     buildCondition(builder, node.getGuardExpression(), body, after);
 
-    loopback.update(newBlock().withSuccessor(builder.getCurrentBlock()));
+    condition.update(ProtoBlockFactory.succeedingTo(builder.getCurrentBlock()));
     builder.addBlockBeforeCurrent();
     return builder;
   }
@@ -522,7 +516,7 @@ private ControlFlowGraphBuilder buildForLoop(
     build(node.getStatement(), builder);
     builder.popLoopContext();
 
-    loopback.update(newBlock().withBranch(node, builder.getCurrentBlock(), after));
+    loopback.update(ProtoBlockFactory.withBranch(node, builder.getCurrentBlock(), after));
 
     builder.setCurrentBlock(loopback);
     parts.forEach(
@@ -563,7 +557,8 @@ private ControlFlowGraphBuilder buildTryFinally(
     builder.addBlockBeforeCurrent();
     // Finally
     FinallyBlockNode finallyNode = node.getFinallyBlock();
-    builder.addBlock(newBlock().withFinallyPath(builder.getCurrentBlock(), builder.getExitBlock()));
+    builder.addBlock(
+        ProtoBlockFactory.finallyBlock(builder.getCurrentBlock(), builder.getExitBlock()));
     build(finallyNode.getStatementList(), builder);
     builder.pushLoopContext(builder.getCurrentBlock(), builder.getCurrentBlock());
     builder.pushExitBlock(builder.getCurrentBlock());
@@ -633,14 +628,14 @@ private ControlFlowGraphBuilder buildTryExcept(
   public ControlFlowGraphBuilder visit(RaiseStatementNode node, ControlFlowGraphBuilder builder) {
     if (node.getRaiseExpression() == null) {
       Set<ProtoBlock> exceptions = builder.getAllCatchTargets();
-      builder.addBlock(newBlock().withExceptions(builder.getCurrentBlock(), exceptions));
+      builder.addBlock(ProtoBlockFactory.withExceptions(builder.getCurrentBlock(), exceptions));
       builder.addElement(node);
       return builder;
     }
 
     Type raiseType = node.getRaiseExpression().getType();
     ProtoBlock jumpTarget = builder.getCatchTarget(raiseType);
-    builder.addBlock(newBlock().withJump(node, jumpTarget, builder.getCurrentBlock()));
+    builder.addBlock(ProtoBlockFactory.jump(node, jumpTarget, builder.getCurrentBlock()));
     return build(node.getRaiseExpression(), builder);
   }
 
@@ -735,7 +730,7 @@ private ControlFlowGraphBuilder buildBooleanLHS(
       BinaryExpressionNode node,
       ProtoBlock trueBlock,
       ProtoBlock falseBlock) {
-    builder.addBlock(newBlock().withBranch(node, trueBlock, falseBlock));
+    builder.addBlock(ProtoBlockFactory.withBranch(node, trueBlock, falseBlock));
     return build(node.getLeft(), builder);
   }
 

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/block/ProtoBlock.java

@@ -45,8 +45,7 @@ public void addElement(DelphiNode element) {
     this.elements.add(element);
   }
 
-  public void update(ProtoBlockBuilder blockBuilder) {
-    ProtoBlock block = blockBuilder.build();
+  public void update(ProtoBlock block) {
     this.blockSupplier = block.blockSupplier;
     this.dataSetter = block.dataSetter;
   }