diff --git a/src/main/java/com/android/tools/r8/cf/code/CfTryCatch.java b/src/main/java/com/android/tools/r8/cf/code/CfTryCatch.java
index 8e9752b..01ff28f 100644
--- a/src/main/java/com/android/tools/r8/cf/code/CfTryCatch.java
+++ b/src/main/java/com/android/tools/r8/cf/code/CfTryCatch.java
@@ -4,7 +4,9 @@
 package com.android.tools.r8.cf.code;
 
 import com.android.tools.r8.graph.CfCompareHelper;
+import com.android.tools.r8.graph.DexClassAndMethod;
 import com.android.tools.r8.graph.DexType;
+import com.android.tools.r8.graph.UseRegistry;
 import com.android.tools.r8.ir.code.BasicBlock;
 import com.android.tools.r8.ir.code.CatchHandlers;
 import com.android.tools.r8.ir.conversion.CfBuilder;
@@ -54,4 +56,8 @@
         .thenComparing(c -> c.targets, ComparatorUtils.listComparator(helper::compareLabels))
         .compare(this, other);
   }
+
+  public void internalRegisterUse(UseRegistry registry, DexClassAndMethod context) {
+    guards.forEach(registry::registerExceptionGuard);
+  }
 }
diff --git a/src/main/java/com/android/tools/r8/graph/CfCode.java b/src/main/java/com/android/tools/r8/graph/CfCode.java
index 141484c..a08d65e 100644
--- a/src/main/java/com/android/tools/r8/graph/CfCode.java
+++ b/src/main/java/com/android/tools/r8/graph/CfCode.java
@@ -508,7 +508,7 @@
     for (CfInstruction instruction : instructions) {
       instruction.registerUse(registry, method);
     }
-    tryCatchRanges.forEach(tryCatch -> tryCatch.guards.forEach(registry::registerTypeReference));
+    tryCatchRanges.forEach(tryCatch -> tryCatch.internalRegisterUse(registry, method));
   }
 
   @Override
diff --git a/src/main/java/com/android/tools/r8/graph/UseRegistry.java b/src/main/java/com/android/tools/r8/graph/UseRegistry.java
index 033182e..4a3327a 100644
--- a/src/main/java/com/android/tools/r8/graph/UseRegistry.java
+++ b/src/main/java/com/android/tools/r8/graph/UseRegistry.java
@@ -75,6 +75,10 @@
     registerTypeReference(type);
   }
 
+  public void registerExceptionGuard(DexType guard) {
+    registerTypeReference(guard);
+  }
+
   public void registerMethodHandle(DexMethodHandle methodHandle, MethodHandleUse use) {
     switch (methodHandle.type) {
       case INSTANCE_GET:
diff --git a/src/main/java/com/android/tools/r8/graph/analysis/EnqueuerExceptionGuardAnalysis.java b/src/main/java/com/android/tools/r8/graph/analysis/EnqueuerExceptionGuardAnalysis.java
new file mode 100644
index 0000000..1bf392e
--- /dev/null
+++ b/src/main/java/com/android/tools/r8/graph/analysis/EnqueuerExceptionGuardAnalysis.java
@@ -0,0 +1,12 @@
+// Copyright (c) 2020, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.graph.analysis;
+
+import com.android.tools.r8.graph.DexType;
+import com.android.tools.r8.graph.ProgramMethod;
+
+public interface EnqueuerExceptionGuardAnalysis {
+  void traceExceptionGuard(DexType guard, ProgramMethod context);
+}
diff --git a/src/main/java/com/android/tools/r8/horizontalclassmerging/policies/NoRuntimeTypeChecks.java b/src/main/java/com/android/tools/r8/horizontalclassmerging/policies/NoRuntimeTypeChecks.java
index dff9967..23f10b2 100644
--- a/src/main/java/com/android/tools/r8/horizontalclassmerging/policies/NoRuntimeTypeChecks.java
+++ b/src/main/java/com/android/tools/r8/horizontalclassmerging/policies/NoRuntimeTypeChecks.java
@@ -18,7 +18,6 @@
   @Override
   public boolean canMerge(DexProgramClass clazz) {
     // We currently assume we only merge classes that implement the same set of interfaces.
-    return !(this.classMergingEnqueuerExtension.isCheckCastType(clazz)
-        || this.classMergingEnqueuerExtension.isInstanceOfType(clazz));
+    return !classMergingEnqueuerExtension.isRuntimeCheckType(clazz);
   }
 }
diff --git a/src/main/java/com/android/tools/r8/shaking/ClassMergingEnqueuerExtension.java b/src/main/java/com/android/tools/r8/shaking/ClassMergingEnqueuerExtension.java
index a6d7326..6a2151b 100644
--- a/src/main/java/com/android/tools/r8/shaking/ClassMergingEnqueuerExtension.java
+++ b/src/main/java/com/android/tools/r8/shaking/ClassMergingEnqueuerExtension.java
@@ -9,15 +9,19 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.graph.ProgramMethod;
 import com.android.tools.r8.graph.analysis.EnqueuerCheckCastAnalysis;
+import com.android.tools.r8.graph.analysis.EnqueuerExceptionGuardAnalysis;
 import com.android.tools.r8.graph.analysis.EnqueuerInstanceOfAnalysis;
 import com.google.common.collect.Sets;
 import java.util.Set;
 
 public class ClassMergingEnqueuerExtension
-    implements EnqueuerInstanceOfAnalysis, EnqueuerCheckCastAnalysis {
+    implements EnqueuerInstanceOfAnalysis,
+        EnqueuerCheckCastAnalysis,
+        EnqueuerExceptionGuardAnalysis {
 
   private final Set<DexType> instanceOfTypes = Sets.newIdentityHashSet();
   private final Set<DexType> checkCastTypes = Sets.newIdentityHashSet();
+  private final Set<DexType> exceptionGuardTypes = Sets.newIdentityHashSet();
   private final DexItemFactory factory;
 
   public ClassMergingEnqueuerExtension(DexItemFactory factory) {
@@ -34,6 +38,11 @@
     instanceOfTypes.add(type.toBaseType(factory));
   }
 
+  @Override
+  public void traceExceptionGuard(DexType guard, ProgramMethod context) {
+    exceptionGuardTypes.add(guard);
+  }
+
   public boolean isCheckCastType(DexProgramClass clazz) {
     return checkCastTypes.contains(clazz.type);
   }
@@ -42,7 +51,18 @@
     return instanceOfTypes.contains(clazz.type);
   }
 
+  public boolean isExceptionGuardType(DexProgramClass clazz) {
+    return exceptionGuardTypes.contains(clazz.type);
+  }
+
+  public boolean isRuntimeCheckType(DexProgramClass clazz) {
+    return isInstanceOfType(clazz) || isCheckCastType(clazz) || isExceptionGuardType(clazz);
+  }
+
   public void attach(Enqueuer enqueuer) {
-    enqueuer.registerInstanceOfAnalysis(this).registerCheckCastAnalysis(this);
+    enqueuer
+        .registerInstanceOfAnalysis(this)
+        .registerCheckCastAnalysis(this)
+        .registerExceptionGuardAnalysis(this);
   }
 }
diff --git a/src/main/java/com/android/tools/r8/shaking/DefaultEnqueuerUseRegistry.java b/src/main/java/com/android/tools/r8/shaking/DefaultEnqueuerUseRegistry.java
index 34fb593..b67d90d 100644
--- a/src/main/java/com/android/tools/r8/shaking/DefaultEnqueuerUseRegistry.java
+++ b/src/main/java/com/android/tools/r8/shaking/DefaultEnqueuerUseRegistry.java
@@ -134,6 +134,11 @@
   }
 
   @Override
+  public void registerExceptionGuard(DexType guard) {
+    enqueuer.traceExceptionGuard(guard, context);
+  }
+
+  @Override
   public void registerMethodHandle(DexMethodHandle methodHandle, MethodHandleUse use) {
     super.registerMethodHandle(methodHandle, use);
     enqueuer.traceMethodHandle(methodHandle, use, context);
diff --git a/src/main/java/com/android/tools/r8/shaking/Enqueuer.java b/src/main/java/com/android/tools/r8/shaking/Enqueuer.java
index 21bf839..230e5ca 100644
--- a/src/main/java/com/android/tools/r8/shaking/Enqueuer.java
+++ b/src/main/java/com/android/tools/r8/shaking/Enqueuer.java
@@ -65,6 +65,7 @@
 import com.android.tools.r8.graph.analysis.DesugaredLibraryConversionWrapperAnalysis;
 import com.android.tools.r8.graph.analysis.EnqueuerAnalysis;
 import com.android.tools.r8.graph.analysis.EnqueuerCheckCastAnalysis;
+import com.android.tools.r8.graph.analysis.EnqueuerExceptionGuardAnalysis;
 import com.android.tools.r8.graph.analysis.EnqueuerInstanceOfAnalysis;
 import com.android.tools.r8.graph.analysis.EnqueuerInvokeAnalysis;
 import com.android.tools.r8.ir.analysis.proto.ProtoEnqueuerUseRegistry;
@@ -178,6 +179,7 @@
   private Set<EnqueuerAnalysis> analyses = Sets.newIdentityHashSet();
   private Set<EnqueuerInvokeAnalysis> invokeAnalyses = Sets.newIdentityHashSet();
   private Set<EnqueuerInstanceOfAnalysis> instanceOfAnalyses = Sets.newIdentityHashSet();
+  private Set<EnqueuerExceptionGuardAnalysis> exceptionGuardAnalyses = Sets.newIdentityHashSet();
   private Set<EnqueuerCheckCastAnalysis> checkCastAnalyses = Sets.newIdentityHashSet();
 
   // Don't hold a direct pointer to app info (use appView).
@@ -436,6 +438,11 @@
     return this;
   }
 
+  public Enqueuer registerExceptionGuardAnalysis(EnqueuerExceptionGuardAnalysis analysis) {
+    exceptionGuardAnalyses.add(analysis);
+    return this;
+  }
+
   public void setAnnotationRemoverBuilder(AnnotationRemover.Builder annotationRemoverBuilder) {
     this.annotationRemoverBuilder = annotationRemoverBuilder;
   }
@@ -1027,6 +1034,11 @@
     traceTypeReference(type, currentMethod);
   }
 
+  void traceExceptionGuard(DexType guard, ProgramMethod currentMethod) {
+    exceptionGuardAnalyses.forEach(analysis -> analysis.traceExceptionGuard(guard, currentMethod));
+    traceTypeReference(guard, currentMethod);
+  }
+
   void traceInvokeDirect(DexMethod invokedMethod, ProgramMethod context) {
     boolean skipTracing =
         registerDeferredActionForDeadProtoBuilder(
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontal/DistinguishExceptionClassesTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontal/DistinguishExceptionClassesTest.java
new file mode 100644
index 0000000..c751735
--- /dev/null
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontal/DistinguishExceptionClassesTest.java
@@ -0,0 +1,57 @@
+// Copyright (c) 2020, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.classmerging.horizontal;
+
+import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import com.android.tools.r8.TestParameters;
+import org.junit.Test;
+
+public class DistinguishExceptionClassesTest extends HorizontalClassMergingTestBase {
+  public DistinguishExceptionClassesTest(
+      TestParameters parameters, boolean enableHorizontalClassMerging) {
+    super(parameters, enableHorizontalClassMerging);
+  }
+
+  @Test
+  public void testR8() throws Exception {
+    testForR8(parameters.getBackend())
+        .addInnerClasses(getClass())
+        .addKeepMainRule(Main.class)
+        .addOptionsModification(
+            options -> options.enableHorizontalClassMerging = enableHorizontalClassMerging)
+        .setMinApi(parameters.getApiLevel())
+        .run(parameters.getRuntime(), Main.class)
+        .assertSuccessWithOutputLines("test success")
+        .inspect(
+            codeInspector -> {
+              assertThat(codeInspector.clazz(Exception1.class), isPresent());
+              assertThat(codeInspector.clazz(Exception2.class), isPresent());
+            });
+  }
+
+  public static class Exception1 extends Exception {}
+
+  public static class Exception2 extends Exception {}
+
+  public static class Main {
+    public static void main(String[] args) {
+      try {
+        try {
+          if (System.currentTimeMillis() > 0) {
+            throw new Exception2();
+          } else {
+            throw new Exception1();
+          }
+        } catch (Exception1 ex) {
+          System.out.println("test failed");
+        }
+      } catch (Exception2 ex) {
+        System.out.println("test success");
+      }
+    }
+  }
+}
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/ExceptionTablesTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/ExceptionTablesTest.java
index 167c6c1..ababe2f 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/ExceptionTablesTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/ExceptionTablesTest.java
@@ -38,7 +38,6 @@
 
   @Test
   public void testClassesHaveBeenMerged() throws Exception {
-    expectThrowsWithHorizontalClassMerging();
     testForR8(parameters.getBackend())
         .addInnerClasses(ExceptionTablesTest.class)
         .addKeepMainRule(TestClass.class)