Add filter for bytecode that javac generates for String in switch (#596)

5 files changed, 104 insertions, 6 deletions

diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/MethodAnalyzer.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/MethodAnalyzer.java
index 8e07e56f..328d079a 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/analysis/MethodAnalyzer.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/MethodAnalyzer.java
@@ -24,6 +24,7 @@ import org.jacoco.core.internal.analysis.filter.IFilter;
 import org.jacoco.core.internal.analysis.filter.IFilterOutput;
 import org.jacoco.core.internal.analysis.filter.LombokGeneratedFilter;
 import org.jacoco.core.internal.analysis.filter.PrivateEmptyNoArgConstructorFilter;
+import org.jacoco.core.internal.analysis.filter.StringSwitchJavacFilter;
 import org.jacoco.core.internal.analysis.filter.SynchronizedFilter;
 import org.jacoco.core.internal.analysis.filter.SyntheticFilter;
 import org.jacoco.core.internal.analysis.filter.TryWithResourcesEcjFilter;
@@ -49,7 +50,8 @@ public class MethodAnalyzer extends MethodProbesVisitor
 	private static final IFilter[] FILTERS = new IFilter[] { new EnumFilter(),
 			new SyntheticFilter(), new SynchronizedFilter(),
 			new TryWithResourcesJavacFilter(), new TryWithResourcesEcjFilter(),
-			new PrivateEmptyNoArgConstructorFilter(), new LombokGeneratedFilter() };
+			new PrivateEmptyNoArgConstructorFilter(),
+			new StringSwitchJavacFilter(), new LombokGeneratedFilter() };
 
 	private final String className;
 
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/AbstractMatcher.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/AbstractMatcher.java
index 50a295de..c5edb2e4 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/AbstractMatcher.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/AbstractMatcher.java
@@ -25,14 +25,13 @@ abstract class AbstractMatcher {
 
 	AbstractInsnNode cursor;
 
-	final void nextIsAddSuppressed() {
+	final void nextIsInvokeVirtual(final String owner, final String name) {
 		nextIs(Opcodes.INVOKEVIRTUAL);
 		if (cursor == null) {
 			return;
 		}
 		final MethodInsnNode m = (MethodInsnNode) cursor;
-		if ("java/lang/Throwable".equals(m.owner)
-				&& "addSuppressed".equals(m.name)) {
+		if (owner.equals(m.owner) && name.equals(m.name)) {
 			return;
 		}
 		cursor = null;
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/StringSwitchJavacFilter.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/StringSwitchJavacFilter.java
new file mode 100644
index 00000000..2824fce9
--- /dev/null
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/StringSwitchJavacFilter.java
@@ -0,0 +1,97 @@
+/*******************************************************************************
+ * Copyright (c) 2009, 2017 Mountainminds GmbH & Co. KG and Contributors
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Evgeny Mandrikov - initial API and implementation
+ *
+ *******************************************************************************/
+package org.jacoco.core.internal.analysis.filter;
+
+import org.objectweb.asm.Opcodes;
+import org.objectweb.asm.tree.AbstractInsnNode;
+import org.objectweb.asm.tree.JumpInsnNode;
+import org.objectweb.asm.tree.LabelNode;
+import org.objectweb.asm.tree.LookupSwitchInsnNode;
+import org.objectweb.asm.tree.MethodNode;
+import org.objectweb.asm.tree.TableSwitchInsnNode;
+
+/**
+ * Filters code that is generated by javac for a switch statement with a String.
+ */
+public final class StringSwitchJavacFilter implements IFilter {
+
+	public void filter(final String className, final String superClassName,
+			final MethodNode methodNode, final IFilterOutput output) {
+		AbstractInsnNode i = methodNode.instructions.getFirst();
+		while (i != null) {
+			filter(i, output);
+			i = i.getNext();
+		}
+	}
+
+	/**
+	 * javac generates two switches. First one by {@link String#hashCode()}.
+	 * Number of handlers in the second switch is equal to number of handlers in
+	 * source code, so it is enough to completely filter-out first switch.
+	 * Handler for default case of the first switch - is the second switch.
+	 */
+	private void filter(final AbstractInsnNode start,
+			final IFilterOutput output) {
+		final LabelNode dflt;
+		if (start.getOpcode() == Opcodes.LOOKUPSWITCH) {
+			dflt = ((LookupSwitchInsnNode) start).dflt;
+		} else if (start.getOpcode() == Opcodes.TABLESWITCH) {
+			dflt = ((TableSwitchInsnNode) start).dflt;
+		} else {
+			return;
+		}
+		if (new Matcher().match(start, dflt)) {
+			output.ignore(start, dflt);
+		}
+	}
+
+	private static class Matcher extends AbstractMatcher {
+		boolean match(final AbstractInsnNode start,
+				final AbstractInsnNode secondSwitchLabel) {
+			cursor = start;
+			for (int i = 0; cursor != null && i < 4; i++) {
+				cursor = cursor.getPrevious();
+			}
+			if (cursor == null || cursor.getOpcode() != Opcodes.ICONST_M1) {
+				return false;
+			}
+			nextIsVar(Opcodes.ISTORE, "c");
+			nextIsVar(Opcodes.ALOAD, "s");
+			nextIsInvokeVirtual("java/lang/String", "hashCode");
+			next();
+			while (true) {
+				nextIsVar(Opcodes.ALOAD, "s");
+				nextIs(Opcodes.LDC);
+				nextIsInvokeVirtual("java/lang/String", "equals");
+				// jump to next comparison or second switch
+				nextIs(Opcodes.IFEQ);
+				// ICONST, BIPUSH or SIPUSH
+				next();
+				nextIsVar(Opcodes.ISTORE, "c");
+				if (cursor == null) {
+					return false;
+				}
+				if (cursor.getNext() == secondSwitchLabel) {
+					break;
+				}
+				nextIs(Opcodes.GOTO);
+				if (((JumpInsnNode) cursor).label != secondSwitchLabel) {
+					return false;
+				}
+			}
+			nextIsVar(Opcodes.ILOAD, "c");
+			nextIs(Opcodes.TABLESWITCH);
+			return cursor != null;
+		}
+	}
+
+}
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesEcjFilter.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesEcjFilter.java
index 7d7d396c..aeceeae4 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesEcjFilter.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesEcjFilter.java
@@ -200,7 +200,7 @@ public final class TryWithResourcesEcjFilter implements IFilter {
 			// "primaryExc.addSuppressed(suppressedExc)"
 			nextIsVar(Opcodes.ALOAD, "primaryExc");
 			nextIsVar(Opcodes.ALOAD, suppressedExc);
-			nextIsAddSuppressed();
+			nextIsInvokeVirtual("java/lang/Throwable", "addSuppressed");
 			nextIsLabel(endLabel);
 			return cursor != null;
 		}
diff --git a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesJavacFilter.java b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesJavacFilter.java
index 02ed47e5..49cacb3a 100644
--- a/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesJavacFilter.java
+++ b/org.jacoco.core/src/org/jacoco/core/internal/analysis/filter/TryWithResourcesJavacFilter.java
@@ -214,7 +214,7 @@ public final class TryWithResourcesJavacFilter implements IFilter {
 				// "primaryExc.addSuppressed(t)"
 				nextIsVar(Opcodes.ALOAD, "primaryExc");
 				nextIsVar(Opcodes.ALOAD, ctx + "t");
-				nextIsAddSuppressed();
+				nextIsInvokeVirtual("java/lang/Throwable", "addSuppressed");
 				nextIs(Opcodes.GOTO);
 				// "r.close()"
 				nextIsClose();