perf: improve ternary mod on big methods (#1379)

jadx-core/src/main/java/jadx/core/dex/attributes/AFlag.java

@@ -76,6 +76,7 @@ public enum AFlag {
 	INCONSISTENT_CODE, // warning about incorrect decompilation
 
 	REQUEST_IF_REGION_OPTIMIZE, // run if region visitor again
+	REQUEST_CODE_SHRINK,
 	RERUN_SSA_TRANSFORM,
 
 	METHOD_CANDIDATE_FOR_INLINE,

jadx-core/src/main/java/jadx/core/dex/visitors/regions/IfRegionVisitor.java

@@ -16,8 +16,6 @@ import jadx.core.utils.RegionUtils;
 import static jadx.core.utils.RegionUtils.insnsCount;
 
 public class IfRegionVisitor extends AbstractVisitor {
-
-	private static final TernaryMod TERNARY_VISITOR = new TernaryMod();
 	private static final ProcessIfRegionVisitor PROCESS_IF_REGION_VISITOR = new ProcessIfRegionVisitor();
 	private static final RemoveRedundantElseVisitor REMOVE_REDUNDANT_ELSE_VISITOR = new RemoveRedundantElseVisitor();
 
@@ -30,7 +28,7 @@ public class IfRegionVisitor extends AbstractVisitor {
 	}
 
 	public static void process(MethodNode mth) {
-		DepthRegionTraversal.traverseIterative(mth, TERNARY_VISITOR);
+		TernaryMod.process(mth);
 		DepthRegionTraversal.traverse(mth, PROCESS_IF_REGION_VISITOR);
 		DepthRegionTraversal.traverseIterative(mth, REMOVE_REDUNDANT_ELSE_VISITOR);
 	}

jadx-core/src/main/java/jadx/core/dex/visitors/regions/TernaryMod.java

@@ -25,10 +25,38 @@ import jadx.core.utils.InsnRemover;
 /**
  * Convert 'if' to ternary operation
  */
-public class TernaryMod implements IRegionIterativeVisitor {
+public class TernaryMod extends AbstractRegionVisitor implements IRegionIterativeVisitor {
+
+	private static final TernaryMod INSTANCE = new TernaryMod();
+
+	public static void process(MethodNode mth) {
+		// first: convert all found ternary nodes in one iteration
+		DepthRegionTraversal.traverse(mth, INSTANCE);
+		if (mth.contains(AFlag.REQUEST_CODE_SHRINK)) {
+			CodeShrinkVisitor.shrinkMethod(mth);
+		}
+		// second: iterative runs with shrink after each change
+		DepthRegionTraversal.traverseIterative(mth, INSTANCE);
+	}
+
+	@Override
+	public boolean enterRegion(MethodNode mth, IRegion region) {
+		if (processRegion(mth, region)) {
+			mth.add(AFlag.REQUEST_CODE_SHRINK);
+		}
+		return true;
+	}
 
 	@Override
 	public boolean visitRegion(MethodNode mth, IRegion region) {
+		if (processRegion(mth, region)) {
+			CodeShrinkVisitor.shrinkMethod(mth);
+			return true;
+		}
+		return false;
+	}
+
+	private static boolean processRegion(MethodNode mth, IRegion region) {
 		if (region instanceof IfRegion) {
 			return makeTernaryInsn(mth, (IfRegion) region);
 		}
@@ -115,9 +143,6 @@ public class TernaryMod implements IRegionIterativeVisitor {
 			header.getInstructions().add(ternInsn);
 
 			clearConditionBlocks(conditionBlocks, header);
-
-			// shrink method again
-			CodeShrinkVisitor.shrinkMethod(mth);
 			return true;
 		}
 
@@ -151,8 +176,6 @@ public class TernaryMod implements IRegionIterativeVisitor {
 			header.add(AFlag.RETURN);
 
 			clearConditionBlocks(conditionBlocks, header);
-
-			CodeShrinkVisitor.shrinkMethod(mth);
 			return true;
 		}
 		return false;
@@ -291,4 +314,7 @@ public class TernaryMod implements IRegionIterativeVisitor {
 		// shrink method again
 		CodeShrinkVisitor.shrinkMethod(mth);
 	}
+
+	private TernaryMod() {
+	}
 }

jadx-core/src/main/java/jadx/core/dex/visitors/shrink/CodeShrinkVisitor.java

@@ -42,6 +42,7 @@ public class CodeShrinkVisitor extends AbstractVisitor {
 		if (mth.isNoCode()) {
 			return;
 		}
+		mth.remove(AFlag.REQUEST_CODE_SHRINK);
 		for (BlockNode block : mth.getBasicBlocks()) {
 			shrinkBlock(mth, block);
 			simplifyMoveInsns(mth, block);