core: don't inline variables defined in 'try' and used in 'catch'

jadx-core/src/main/java/jadx/core/Jadx.java

@@ -57,13 +57,13 @@ public class Jadx {
 			passes.add(new SSATransform());
 			passes.add(new DebugInfoVisitor());
 			passes.add(new TypeInference());
+			if (args.isRawCFGOutput()) {
+				passes.add(new DotGraphVisitor(outDir, false, true));
+			}
 
 			passes.add(new ConstInlinerVisitor());
 			passes.add(new FinishTypeInference());
 			passes.add(new EliminatePhiNodes());
-			if (args.isRawCFGOutput()) {
-				passes.add(new DotGraphVisitor(outDir, false, true));
-			}
 
 			passes.add(new ModVisitor());
 			passes.add(new EnumVisitor());

jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java

@@ -442,6 +442,10 @@ public class MethodNode extends LineAttrNode implements ILoadable {
 		return exceptionHandlers.isEmpty();
 	}
 
+	public int getExceptionHandlersCount() {
+		return exceptionHandlers.size();
+	}
+
 	/**
 	 * Return true if exists method with same name and arguments count
 	 */

jadx-core/src/main/java/jadx/core/dex/visitors/ConstInlinerVisitor.java

@@ -8,9 +8,11 @@ import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.instructions.args.InsnArg;
 import jadx.core.dex.instructions.args.LiteralArg;
 import jadx.core.dex.instructions.args.RegisterArg;
+import jadx.core.dex.instructions.args.SSAVar;
 import jadx.core.dex.nodes.BlockNode;
 import jadx.core.dex.nodes.InsnNode;
 import jadx.core.dex.nodes.MethodNode;
+import jadx.core.utils.BlockUtils;
 import jadx.core.utils.InstructionRemover;
 import jadx.core.utils.exceptions.JadxException;
 
@@ -24,35 +26,52 @@ public class ConstInlinerVisitor extends AbstractVisitor {
 		if (mth.isNoCode()) {
 			return;
 		}
+		List<InsnNode> toRemove = new ArrayList<InsnNode>();
 		for (BlockNode block : mth.getBasicBlocks()) {
-			InstructionRemover remover = new InstructionRemover(mth, block);
+			toRemove.clear();
 			for (InsnNode insn : block.getInstructions()) {
 				if (checkInsn(mth, block, insn)) {
-					remover.add(insn);
+					toRemove.add(insn);
 				}
 			}
-			remover.perform();
+			if (!toRemove.isEmpty()) {
+				InstructionRemover.removeAll(mth, block, toRemove);
+			}
 		}
 	}
 
 	private static boolean checkInsn(MethodNode mth, BlockNode block, InsnNode insn) {
-		if (insn.getType() == InsnType.CONST) {
-			InsnArg arg = insn.getArg(0);
-			if (arg.isLiteral()) {
-				ArgType resType = insn.getResult().getType();
-				// make sure arg has correct type
-				if (!arg.getType().isTypeKnown()) {
-					arg.merge(resType);
+		if (insn.getType() != InsnType.CONST) {
+			return false;
+		}
+		InsnArg arg = insn.getArg(0);
+		if (!arg.isLiteral()) {
+			return false;
+		}
+		SSAVar sVar = insn.getResult().getSVar();
+		if (mth.getExceptionHandlersCount() != 0) {
+			for (RegisterArg useArg : sVar.getUseList()) {
+				InsnNode parentInsn = useArg.getParentInsn();
+				if (parentInsn != null) {
+					// TODO: speed up expensive operations
+					BlockNode useBlock = BlockUtils.getBlockByInsn(mth, parentInsn);
+					if (!BlockUtils.isCleanPathExists(block, useBlock)) {
+						return false;
+					}
 				}
-				long lit = ((LiteralArg) arg).getLiteral();
-				return replaceConst(mth, insn, lit);
 			}
 		}
-		return false;
+		ArgType resType = insn.getResult().getType();
+		// make sure arg has correct type
+		if (!arg.getType().isTypeKnown()) {
+			arg.merge(resType);
+		}
+		long lit = ((LiteralArg) arg).getLiteral();
+		return replaceConst(mth, sVar, lit);
 	}
 
-	private static boolean replaceConst(MethodNode mth, InsnNode insn, long literal) {
-		List<RegisterArg> use = new ArrayList<RegisterArg>(insn.getResult().getSVar().getUseList());
+	private static boolean replaceConst(MethodNode mth, SSAVar sVar, long literal) {
+		List<RegisterArg> use = new ArrayList<RegisterArg>(sVar.getUseList());
 		int replaceCount = 0;
 		for (RegisterArg arg : use) {
 //			if (arg.getSVar().isUsedInPhi()) {

jadx-core/src/main/java/jadx/core/utils/BlockUtils.java

@@ -216,6 +216,29 @@ public class BlockUtils {
 		return traverseSuccessorsUntil(start, end, new BitSet());
 	}
 
+	public static boolean isCleanPathExists(BlockNode start, BlockNode end) {
+		if (start == end || start.getCleanSuccessors().contains(end)) {
+			return true;
+		}
+		return traverseCleanSuccessorsUntil(start, end, new BitSet());
+	}
+
+	private static boolean traverseCleanSuccessorsUntil(BlockNode from, BlockNode until, BitSet visited) {
+		for (BlockNode s : from.getCleanSuccessors()) {
+			if (s == until) {
+				return true;
+			}
+			int id = s.getId();
+			if (!visited.get(id) && !s.contains(AType.EXC_HANDLER)) {
+				visited.set(id);
+				if (traverseSuccessorsUntil(s, until, visited)) {
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+
 	public static boolean isOnlyOnePathExists(BlockNode start, BlockNode end) {
 		if (start == end) {
 			return true;

jadx-core/src/main/java/jadx/core/utils/InstructionRemover.java

@@ -47,7 +47,7 @@ public class InstructionRemover {
 		if (toRemove.isEmpty()) {
 			return;
 		}
-		removeAll(insns, toRemove);
+		removeAll(mth, insns, toRemove);
 		toRemove.clear();
 	}
 
@@ -86,7 +86,7 @@ public class InstructionRemover {
 
 	// Don't use 'insns.removeAll(toRemove)' because it will remove instructions by content
 	// and here can be several instructions with same content
-	private void removeAll(List<InsnNode> insns, List<InsnNode> toRemove) {
+	private static void removeAll(MethodNode mth, List<InsnNode> insns, List<InsnNode> toRemove) {
 		for (InsnNode rem : toRemove) {
 			unbindInsn(mth, rem);
 			int insnsCount = insns.size();
@@ -119,6 +119,10 @@ public class InstructionRemover {
 		}
 	}
 
+	public static void removeAll(MethodNode mth, BlockNode block, List<InsnNode> insns) {
+		removeAll(mth, block.getInstructions(), insns);
+	}
+
 	public static void remove(MethodNode mth, BlockNode block, int index) {
 		List<InsnNode> instructions = block.getInstructions();
 		unbindInsn(mth, instructions.get(index));

jadx-core/src/test/java/jadx/api/InternalJadxTest.java

@@ -29,6 +29,7 @@ import static org.junit.Assert.fail;
 public abstract class InternalJadxTest extends TestUtils {
 
 	protected boolean outputCFG = false;
+	protected boolean isFallback = false;
 	protected boolean deleteTmpJar = true;
 
 	protected String outDir = "test-out-tmp";
@@ -76,6 +77,11 @@ public abstract class InternalJadxTest extends TestUtils {
 			public boolean isRawCFGOutput() {
 				return outputCFG;
 			}
+
+			@Override
+			public boolean isFallbackMode() {
+				return isFallback;
+			}
 		}, new File(outDir));
 	}
 
@@ -136,6 +142,12 @@ public abstract class InternalJadxTest extends TestUtils {
 		this.outputCFG = true;
 	}
 
+	// Use only for debug purpose
+	@Deprecated
+	protected void setFallback() {
+		this.isFallback = true;
+	}
+
 	// Use only for debug purpose
 	@Deprecated
 	protected void notDeleteTmpJar() {

jadx-core/src/test/java/jadx/tests/internal/others/TestIfInTry.java

@@ -41,7 +41,6 @@ public class TestIfInTry extends InternalJadxTest {
 
 	@Test
 	public void test() {
-		setOutputCFG();
 		ClassNode cls = getClassNode(TestCls.class);
 		String code = cls.getCode().toString();
 		System.out.println(code);

jadx-core/src/test/java/jadx/tests/internal/trycatch/TestInlineInCatch.java

+package jadx.tests.internal.trycatch;
+
+import jadx.api.InternalJadxTest;
+import jadx.core.dex.nodes.ClassNode;
+
+import java.io.File;
+
+import org.junit.Test;
+
+import static jadx.tests.utils.JadxMatchers.containsOne;
+import static org.junit.Assert.assertThat;
+
+public class TestInlineInCatch extends InternalJadxTest {
+
+	public static class TestCls {
+		private File dir;
+
+		public int test() {
+			File output = null;
+			try {
+				output = File.createTempFile("f", "a", dir);
+				return 0;
+			} catch (Exception e) {
+				if (output != null) {
+					output.delete();
+				}
+				return 2;
+			}
+		}
+	}
+
+	@Test
+	public void test() {
+		ClassNode cls = getClassNode(TestCls.class);
+		String code = cls.getCode().toString();
+		System.out.println(code);
+
+		assertThat(code, containsOne("File output = null;"));
+		assertThat(code, containsOne("output = File.createTempFile(\"f\", \"a\", "));
+		assertThat(code, containsOne("return 0;"));
+		assertThat(code, containsOne("} catch (Exception e) {"));
+		assertThat(code, containsOne("if (output != null) {"));
+		assertThat(code, containsOne("output.delete();"));
+		assertThat(code, containsOne("return 2;"));
+	}
+}