diff --git a/README.md b/README.md
index 2120f90..b1574cd 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,6 @@ it's "good enough" to get started, and I can return to demo coding with its curr
 
 ## Known issues
 
-- Performance is not optimal yet (no stub index).
 - No referencing of macro invocations and macro definitions.
 - `Find Usages` always shows _"Unclassified"_ though it shouldn't.
 - Macro definitions may cause syntax errors when using backslash arguments.
@@ -55,9 +54,14 @@ it's "good enough" to get started, and I can return to demo coding with its curr
     - Formatter + Code Style Settings
     - Register use analysis (but this only makes sense after macro evaluation)
 
+## Recommendations
+
+Currently, I would suggest using the fabulous [Browse Word at Caret Plugin](https://plugins.jetbrains.com/plugin/201-browsewordatcaret)
+to highlight the same address and data registers while editing (see new `View -> Highlight Word at Caret` menu item).
+
 ## Development notice
 
-This plugin has been written in Kotlin 1.5.
+This plugin has been written in Kotlin 1.5 using Grammar-Kit.
 
 It is probably the only plugin (besides [Cajon](https://github.com/chrisly42/cajon-plugin) from the same author) that uses JUnit 5 Jupiter for unit testing so
 far (or at least the only one I'm aware of ;) ). The IntelliJ framework actually uses the JUnit 3 TestCase for plugin testing, and it took me quite a while to
@@ -65,6 +69,12 @@ make it work with JUnit 5. Feel free to use the code (in package ```de.platon42.
 
 ## Changelog
 
+### V0.2 (unreleased)
+
+- Added (same) icon for plugin as for file type.
+- Performance improvement: Use Word-Index for global labels and symbols instead of iterating over the file.
+- Performance improvement: Use Stub-Index for global labels and symbols.
+
 ### V0.1 (20-Jul-21)
 
 - Initial public release.
\ No newline at end of file
diff --git a/build.gradle b/build.gradle
index 658fe0d..43c6367 100644
--- a/build.gradle
+++ b/build.gradle
@@ -46,6 +46,12 @@ intellij {
 
 patchPluginXml {
     setChangeNotes("""
+  <h4>V0.2 (xx-Jul-21)</h4>
+    <ul>
+      <li>Added (same) icon for plugin as for file type.
+      <li>Performance improvement: Use Word-Index for global labels and symbols instead of iterating over the file.
+      <li>Performance improvement: Use Stub-Index for global labels and symbols.
+    </ul>
   <h4>V0.1 (20-Jul-21)</h4>
     <ul>
       <li>Initial public release.
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt b/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt
index 0d9a827..fab0724 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt
@@ -1,28 +1,41 @@
 package de.platon42.intellij.plugins.m68k.psi
 
 import com.intellij.openapi.project.Project
-import com.intellij.psi.PsiManager
-import com.intellij.psi.search.FileTypeIndex
 import com.intellij.psi.search.GlobalSearchScope
+import com.intellij.psi.stubs.StubIndex
 import com.intellij.psi.util.PsiTreeUtil
-import de.platon42.intellij.plugins.m68k.M68kFileType
+import de.platon42.intellij.plugins.m68k.stubs.M68kGlobalLabelStubIndex
+import de.platon42.intellij.plugins.m68k.stubs.M68kSymbolDefinitionStubIndex
 
 object M68kLookupUtil {
 
     fun findAllGlobalLabels(project: Project): List<M68kGlobalLabel> {
-        return getFiles(project)
-            .flatMap(::findAllGlobalLabels)
-            .toList()
+        val results: MutableList<M68kGlobalLabel> = ArrayList()
+        StubIndex.getInstance().processAllKeys(M68kGlobalLabelStubIndex.KEY, project)
+        {
+            results.addAll(StubIndex.getElements(M68kGlobalLabelStubIndex.KEY, it, project, GlobalSearchScope.allScope(project), M68kGlobalLabel::class.java))
+            true
+        }
+        return results
     }
 
     fun findAllGlobalLabels(file: M68kFile): List<M68kGlobalLabel> {
         val results: MutableList<M68kGlobalLabel> = ArrayList()
-        var currentStatement = file.firstChild
-        while (currentStatement != null) {
-            val child = currentStatement.firstChild
-            if (child is M68kGlobalLabel) results.add(child)
-            currentStatement = PsiTreeUtil.getNextSiblingOfType(currentStatement, M68kStatement::class.java)
-        }
+        StubIndex.getInstance().processAllKeys(
+            M68kGlobalLabelStubIndex.KEY,
+            {
+                results.addAll(
+                    StubIndex.getElements(
+                        M68kGlobalLabelStubIndex.KEY,
+                        it,
+                        file.project,
+                        GlobalSearchScope.fileScope(file),
+                        M68kGlobalLabel::class.java
+                    )
+                )
+                true
+            }, GlobalSearchScope.fileScope(file), null
+        )
         return results
     }
 
@@ -40,23 +53,40 @@ object M68kLookupUtil {
     }
 
     fun findAllSymbolDefinitions(project: Project): List<M68kSymbolDefinition> {
-        return getFiles(project)
-            .flatMap(::findAllSymbolDefinitions)
-            .toList()
-    }
-
-    fun findAllSymbolDefinitions(file: M68kFile): List<M68kSymbolDefinition> {
         val results: MutableList<M68kSymbolDefinition> = ArrayList()
-        var currentStatement = file.firstChild
-        while (currentStatement != null) {
-            val child = currentStatement.firstChild
-            if (child is M68kAssignment) results.add(child.firstChild as M68kSymbolDefinition)
-            currentStatement = PsiTreeUtil.getNextSiblingOfType(currentStatement, M68kStatement::class.java)
+        StubIndex.getInstance().processAllKeys(M68kSymbolDefinitionStubIndex.KEY, project)
+        {
+            results.addAll(
+                StubIndex.getElements(
+                    M68kSymbolDefinitionStubIndex.KEY,
+                    it,
+                    project,
+                    GlobalSearchScope.allScope(project),
+                    M68kSymbolDefinition::class.java
+                )
+            )
+            true
         }
         return results
     }
 
-    private fun getFiles(project: Project) =
-        FileTypeIndex.getFiles(M68kFileType.INSTANCE, GlobalSearchScope.allScope(project)).asSequence()
-            .map { PsiManager.getInstance(project).findFile(it) as M68kFile }
+    fun findAllSymbolDefinitions(file: M68kFile): List<M68kSymbolDefinition> {
+        val results: MutableList<M68kSymbolDefinition> = ArrayList()
+        StubIndex.getInstance().processAllKeys(
+            M68kSymbolDefinitionStubIndex.KEY,
+            {
+                results.addAll(
+                    StubIndex.getElements(
+                        M68kSymbolDefinitionStubIndex.KEY,
+                        it,
+                        file.project,
+                        GlobalSearchScope.fileScope(file),
+                        M68kSymbolDefinition::class.java
+                    )
+                )
+                true
+            }, GlobalSearchScope.fileScope(file), null
+        )
+        return results
+    }
 }
\ No newline at end of file
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
index a93ca86..d87ef2a 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
@@ -4,6 +4,7 @@ import com.intellij.ide.structureView.StructureViewTreeElement
 import com.intellij.ide.util.treeView.smartTree.TreeElement
 import com.intellij.navigation.ItemPresentation
 import com.intellij.psi.NavigatablePsiElement
+import com.intellij.refactoring.suggested.startOffset
 import de.platon42.intellij.plugins.m68k.psi.M68kFile
 import de.platon42.intellij.plugins.m68k.psi.M68kGlobalLabel
 import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
@@ -18,8 +19,10 @@ class M68kStructureViewElement(private val myElement: NavigatablePsiElement) : S
         return when (myElement) {
             is M68kFile -> {
                 listOf(
-                    M68kLookupUtil.findAllSymbolDefinitions(myElement),
-                    M68kLookupUtil.findAllGlobalLabels(myElement)
+                    M68kLookupUtil.findAllSymbolDefinitions(myElement).sortedBy { it.startOffset },
+                    M68kLookupUtil.findAllGlobalLabels(myElement).sortedBy { it.startOffset },
+//                    M68kLookupUtil.findAllSymbolDefinitions(myElement).sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.name!! }),
+//                    M68kLookupUtil.findAllGlobalLabels(myElement).sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.name!! })
                 )
                     .flatten()
                     .map(::M68kStructureViewElement)
diff --git a/src/test/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewTest.kt b/src/test/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewTest.kt
new file mode 100644
index 0000000..98f65af
--- /dev/null
+++ b/src/test/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewTest.kt
@@ -0,0 +1,37 @@
+package de.platon42.intellij.plugins.m68k.structureview
+
+import com.intellij.testFramework.PlatformTestUtil
+import com.intellij.testFramework.fixtures.CodeInsightTestFixture
+import de.platon42.intellij.jupiter.LightCodeInsightExtension
+import de.platon42.intellij.jupiter.MyFixture
+import de.platon42.intellij.jupiter.TestDataPath
+import de.platon42.intellij.plugins.m68k.AbstractM68kTest
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+
+@TestDataPath("src/test/resources/structureview")
+@ExtendWith(LightCodeInsightExtension::class)
+internal class M68kStructureViewTest : AbstractM68kTest() {
+
+    @Test
+    internal fun do_basic_verification_of_resulting_structure_view(@MyFixture myFixture: CodeInsightTestFixture) {
+        myFixture.configureByFile("basic_example.asm")
+        myFixture.testStructureView {
+            val tree = it.tree
+            PlatformTestUtil.waitWhileBusy(tree)
+            PlatformTestUtil.assertTreeEqual(
+                tree, """-basic_example.asm
+ PIC_WIDTH
+ PIC_HEIGHT
+ DEBUG_LEVEL
+ entry
+ -init
+  .looph
+  .loopw
+ main
+ exit
+"""
+            )
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/test/resources/structureview/basic_example.asm b/src/test/resources/structureview/basic_example.asm
new file mode 100644
index 0000000..a7e9edd
--- /dev/null
+++ b/src/test/resources/structureview/basic_example.asm
@@ -0,0 +1,25 @@
+PIC_WIDTH = 320
+PIC_HEIGHT equ 256
+DEBUG_LEVEL set 10
+
+entry:
+        bsr     init
+        bsr     main
+        bsr     exit
+        rts
+
+init
+        move.w  #PIC_HEIGHT,d1
+.looph  move.w  #PIC_WIDTH,d0
+.loopw  clr.b   (a0)+
+        subq.w  #1,d0
+        bne.s   .loopw
+        subq.w  #1,d1
+        bne.s   .looph
+        rts
+
+main    moveq.l #0,d0
+        rts
+
+exit    illegal
+        rts
\ No newline at end of file