From d2f248dc70dce74281384a5ad1243c346a872081 Mon Sep 17 00:00:00 2001
From: Alena Laskavaia <elaskavaia.cdt@gmail.com>
Date: Tue, 9 Sep 2014 22:42:19 -0400
Subject: [PATCH] Bug 353352 - CFG doesn't handle range-based for loop

Change-Id: Ic71c15d26d31d954fbc4c91882dd9361d9b23eae
---
 .../model/cfg/ControlFlowGraphBuilder.java    | 43 ++++++++++--
 .../codan/core/cfg/ControlFlowGraphTest.java  | 69 +++++++++++++++++--
 2 files changed, 101 insertions(+), 11 deletions(-)

diff --git a/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/internal/model/cfg/ControlFlowGraphBuilder.java b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/internal/model/cfg/ControlFlowGraphBuilder.java
index 82c004ab60d..fa609834f05 100644
--- a/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/internal/model/cfg/ControlFlowGraphBuilder.java
+++ b/codan/org.eclipse.cdt.codan.core.cxx/src/org/eclipse/cdt/codan/core/cxx/internal/model/cfg/ControlFlowGraphBuilder.java
@@ -183,9 +183,8 @@ public class ControlFlowGraphBuilder {
 				conn = (IConnectorNode) labNode.getOutgoing();
 				addOutgoing(prev, labNode);
 			} else {
-				// labeled statement contains of connector for jumps, branch for
-				// label
-				// and nested statement
+				// labeled statement consists of connectors for jumps, branch for
+				// label and nested statement
 				conn = createLabelNodes(prev, labelName);
 			}
 			return createSubGraph(conn, ast.getNestedStatement());
@@ -383,8 +382,42 @@ public class ControlFlowGraphBuilder {
 	}
 
 	private IBasicBlock createRangeBasedFor(IBasicBlock prev, ICPPASTRangeBasedForStatement forNode) {
-		// TODO(Alena Laskavaia): Implement proper graph.
-		return createSubGraph(prev, forNode.getBody());
+		// Add initializer
+		IPlainNode init = factory.createPlainNode(forNode.getDeclaration());
+		addOutgoing(prev, init);
+		prev = init;
+		// Add continue connector
+		IConnectorNode beforeCheck = factory.createConnectorNode();
+		addOutgoing(prev, beforeCheck);
+		// Decision node
+		CxxDecisionNode decision = factory.createDecisionNode(forNode.getInitializerClause()); // XXX test expression
+		addOutgoing(beforeCheck, decision);
+		// Add break connector
+		IConnectorNode nBreak = factory.createConnectorNode();
+		decision.setMergeNode(nBreak);
+		// Create body and jump to continue node
+		IBranchNode loopStart = factory.createBranchNode(IBranchNode.THEN);
+		addOutgoing(decision, loopStart);
+		// Set break/continue
+		IConnectorNode nContinue = factory.createConnectorNode();
+		IConnectorNode savedContinue = outerContinue;
+		IConnectorNode savedBreak = outerBreak;
+		outerContinue = nContinue;
+		outerBreak = nBreak;
+		IBasicBlock endBody = createSubGraph(loopStart, forNode.getBody());
+		outerContinue = savedContinue;
+		outerBreak = savedBreak;
+		// inc
+		IPlainNode inc = factory.createPlainNode(); // XXX increment
+		addOutgoing(endBody, nContinue);
+		addOutgoing(nContinue, inc);
+		// Connect with backward link
+		addJump(inc, beforeCheck, true);
+		// Add "else" branch
+		IBranchNode loopEnd = factory.createBranchNode(IBranchNode.ELSE);
+		addOutgoing(decision, loopEnd);
+		addJump(loopEnd, nBreak);
+		return nBreak;
 	}
 
 	protected IBasicBlock createWhile(IBasicBlock prev, IASTWhileStatement body) {
diff --git a/codan/org.eclipse.cdt.codan.core.test/src/org/eclipse/cdt/codan/core/cfg/ControlFlowGraphTest.java b/codan/org.eclipse.cdt.codan.core.test/src/org/eclipse/cdt/codan/core/cfg/ControlFlowGraphTest.java
index d483f52b425..e1cf5596a41 100644
--- a/codan/org.eclipse.cdt.codan.core.test/src/org/eclipse/cdt/codan/core/cfg/ControlFlowGraphTest.java
+++ b/codan/org.eclipse.cdt.codan.core.test/src/org/eclipse/cdt/codan/core/cfg/ControlFlowGraphTest.java
@@ -65,7 +65,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 	}
 
 	/**
-	 * 
+	 *
 	 */
 	private void checkCfg(boolean decision) {
 		assertNotNull(graph);
@@ -153,6 +153,14 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 		processAst(tu);
 	}
 
+	private void buildCfg_C(String code) {
+		parse(code, ParserLanguage.C, true);
+		processAst(tu);
+	}
+	private void buildCfg_CPP(String code) {
+		parse(code, ParserLanguage.CPP, true);
+		processAst(tu);
+	}
 	/**
 	 * @param des
 	 * @return
@@ -163,7 +171,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 
 	/**
 	 * Return first node after the branch
-	 * 
+	 *
 	 * @param des
 	 * @return
 	 */
@@ -180,7 +188,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 
 	/**
 	 * Return node where control jumps, following the chain until jump is hit
-	 * 
+	 *
 	 * @param a
 	 * @return
 	 */
@@ -199,7 +207,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 
 	//	 main() {
 	//	   int a;
-	//	   a=1; 
+	//	   a=1;
 	//	 }
 	public void test_basic() {
 		buildAndCheck(getAboveComment());
@@ -342,7 +350,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 
 	/*
 	 * (non-Javadoc)
-	 * 
+	 *
 	 * @see org.eclipse.cdt.codan.core.test.CodanFastCxxAstTestCase#getChecker()
 	 */
 	@Override
@@ -436,7 +444,7 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 //	    }
 //	}
 	public void test_infiniloop() {
-		buildCfg(getAboveComment(), false);
+		buildCfg_C(getAboveComment());
 		checkCfg(false);
 		IStartNode startNode = graph.getStartNode();
 		IConnectorNode conn = (IConnectorNode) startNode.getOutgoing();
@@ -450,4 +458,53 @@ public class ControlFlowGraphTest extends CodanFastCxxAstTestCase {
 		assertNotNull(m2);
 		assertNull(m1);
 	}
+
+	//	void foo() {
+	//    for (int i=0;i<N;i++) {
+	//        bar();
+	//    }
+	//}
+	public void test_for() {
+		buildCfg_CPP(getAboveComment());
+		checkCfg(false);
+
+		IStartNode startNode = graph.getStartNode();
+		IPlainNode decl = (IPlainNode) startNode.getOutgoing();
+		IConnectorNode conn = (IConnectorNode) decl.getOutgoing();
+		IDecisionNode des = (IDecisionNode) conn.getOutgoing();
+		assertEquals("i<N", data(des));
+		IPlainNode bThen = (IPlainNode) branchEnd(des, IBranchNode.THEN);
+		assertEquals("bar();", data(bThen));
+		IBasicBlock bElse = branchEnd(des, IBranchNode.ELSE);
+
+		IBasicBlock m1 = jumpEnd(bElse);
+		IBasicBlock m2 = bThen.getOutgoing();
+		assertNotNull(m1);
+		assertSame(conn, jumpEnd(bThen));
+		assertEquals("i++", data(((IConnectorNode) m2).getOutgoing()));
+	}
+
+	//	void foo() {
+	//	    for (int i : arr) {
+	//	        bar();
+	//	    }
+	//	}
+	public void test_range_loop() {
+		buildCfg_CPP(getAboveComment());
+		checkCfg(false);
+
+		IStartNode startNode = graph.getStartNode();
+		IPlainNode decl = (IPlainNode) startNode.getOutgoing();
+		IConnectorNode conn = (IConnectorNode) decl.getOutgoing();
+		IDecisionNode des = (IDecisionNode) conn.getOutgoing();
+		assertEquals("arr", data(des)); // condition
+		IPlainNode bThen = (IPlainNode) branchEnd(des, IBranchNode.THEN);
+		assertEquals("bar();", data(bThen));
+		IBasicBlock bElse = branchEnd(des, IBranchNode.ELSE);
+		assertNotNull(bElse);
+		IBasicBlock m2 = bThen.getOutgoing();
+
+		assertSame(conn, jumpEnd(bThen));
+		assertEquals("", data(((IConnectorNode) m2).getOutgoing())); // increment
+	}
 }