Add comments to decompiled code and remove logging

Vineflower · Aug 20, 2024 · af7f656 · af7f656
1 parent c80be61
commit af7f656
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Showing 5 changed files with 259 additions and 240 deletions.
diff --git a/src/org/jetbrains/java/decompiler/main/extern/IFernflowerPreferences.java b/src/org/jetbrains/java/decompiler/main/extern/IFernflowerPreferences.java
@@ -226,7 +226,7 @@ public interface IFernflowerPreferences {
   String VERIFY_VARIABLE_MERGES = "verify-merges";
 
   @Name("[Experimental] Use old try deduplication")
-  @Description("Uses the older try deduplication algorithm for methods with obfuscated exceptions, which prefers ")
+  @Description("Use the old try deduplication algorithm for methods with obfuscated exceptions, which inserts dummy exception handlers instead of duplicating blocks")
   @Type(DecompilerOption.Type.BOOLEAN)
   String OLD_TRY_DEDUP = "old-try-dedup";
 

diff --git a/src/org/jetbrains/java/decompiler/main/rels/MethodProcessor.java b/src/org/jetbrains/java/decompiler/main/rels/MethodProcessor.java
@@ -137,7 +137,6 @@ public static RootStatement codeToJava(StructClass cl, StructMethod mt, MethodDe
     DecompilerContext.getCounterContainer().setCounter(CounterContainer.VAR_COUNTER, mt.getLocalVariables());
 
     if (ExceptionDeobfuscator.hasObfuscatedExceptions(graph)) {
-      DecompilerContext.getLogger().writeMessage("Heavily obfuscated exception ranges found!", IFernflowerLogger.Severity.WARN);
       DotExporter.toDotFile(graph, mt, "cfgExceptionsPre", true);
 
       if (!ExceptionDeobfuscator.handleMultipleEntryExceptionRanges(graph)) {

diff --git a/src/org/jetbrains/java/decompiler/modules/decompiler/deobfuscator/ExceptionDeobfuscator.java b/src/org/jetbrains/java/decompiler/modules/decompiler/deobfuscator/ExceptionDeobfuscator.java
@@ -12,6 +12,7 @@
 import org.jetbrains.java.decompiler.modules.decompiler.decompose.GenericDominatorEngine;
 import org.jetbrains.java.decompiler.modules.decompiler.decompose.IGraph;
 import org.jetbrains.java.decompiler.modules.decompiler.decompose.IGraphNode;
+import org.jetbrains.java.decompiler.struct.StructClass;
 import org.jetbrains.java.decompiler.util.InterpreterUtil;
 
 import java.util.*;
@@ -441,7 +442,9 @@ public static void insertDummyExceptionHandlerBlocks(ControlFlowGraph graph, Byt
           }
         }
 
-        // TODO: write comment if not matchexception
+        if (!isMatchException(handler)) {
+          graph.addComment("$VF: Duplicated exception handlers to handle obfuscated exceptions");
+        }
 
       } else {
         for (ExceptionRangeCFG range : ranges) {
@@ -487,4 +490,20 @@ public static void insertDummyExceptionHandlerBlocks(ControlFlowGraph graph, Byt
       }
     }
   }
-}
+
+  private static boolean isMatchException(BasicBlock block) {
+    StructClass cl = DecompilerContext.getContextProperty(DecompilerContext.CURRENT_CLASS);
+
+    // Check if block has any "new MatchException;"
+    for (Instruction instr : block.getSeq()) {
+      if (instr.opcode == CodeConstants.opc_new) {
+        if ("java/lang/MatchException".equals(cl.getPool().getPrimitiveConstant(instr.operand(0)).getString())) {
+          return true;
+
+        }
+      }
+    }
+
+    return false;
+  }
+}
diff --git a/src/org/jetbrains/java/decompiler/struct/consts/PrimitiveConstant.java b/src/org/jetbrains/java/decompiler/struct/consts/PrimitiveConstant.java
@@ -47,4 +47,4 @@ public boolean equals(Object o) {
            this.isArray == cn.isArray &&
            this.value.equals(cn.value);
   }
-}
+}