Remove unnecessary allocations with scatter maps

romainguy · May 16, 2024 · 6a6b743 · 6a6b743
1 parent 8fd00d7
commit 6a6b743
Show file tree

Hide file tree

Showing 3 changed files with 22 additions and 14 deletions.
diff --git a/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/Code.kt b/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/Code.kt
@@ -16,6 +16,7 @@
 
 package dev.romainguy.kotlin.explorer.code
 
+import androidx.collection.IntIntMap
 
 /**
  * A data model representing disassembled code
@@ -26,15 +27,15 @@ package dev.romainguy.kotlin.explorer.code
  */
 class Code(
     val text: String,
-    private val jumps: Map<Int, Int>,
-    private val sourceToCodeLine: Map<Int, Int>,
-    private val codeToSourceToLine: Map<Int, Int>,
+    private val jumps: IntIntMap,
+    private val sourceToCodeLine: IntIntMap,
+    private val codeToSourceToLine: IntIntMap,
 ) {
-    fun getJumpTargetOfLine(line: Int) = jumps[line]
+    fun getJumpTargetOfLine(line: Int) = jumps.getOrDefault(line, -1)
 
-    fun getCodeLine(sourceLine: Int) = sourceToCodeLine[sourceLine]
+    fun getCodeLine(sourceLine: Int) = sourceToCodeLine.getOrDefault(sourceLine, -1)
 
-    fun getSourceLine(codeLine: Int) = codeToSourceToLine[codeLine]
+    fun getSourceLine(codeLine: Int) = codeToSourceToLine.getOrDefault(codeLine, -1)
 
     companion object {
         fun fromClasses(classes: List<Class>, codeStyle: CodeStyle = CodeStyle()): Code {

diff --git a/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/CodeBuilder.kt b/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/CodeBuilder.kt
@@ -16,6 +16,9 @@
 
 package dev.romainguy.kotlin.explorer.code
 
+import androidx.collection.IntIntPair
+import androidx.collection.mutableIntIntMapOf
+
 fun buildCode(codeStyle: CodeStyle = CodeStyle(), builderAction: CodeBuilder.() -> Unit): CodeBuilder {
     return CodeBuilder(codeStyle).apply(builderAction)
 }
@@ -29,13 +32,13 @@ fun buildCode(codeStyle: CodeStyle = CodeStyle(), builderAction: CodeBuilder.()
 class CodeBuilder(private val codeStyle: CodeStyle) {
     private var line = 0
     private val sb = StringBuilder()
-    private val jumps = mutableMapOf<Int, Int>()
-    private val sourceToCodeLine = mutableMapOf<Int, Int>()
-    private val codeToSourceToLine = mutableMapOf<Int, Int>()
+    private val jumps = mutableIntIntMapOf()
+    private val sourceToCodeLine = mutableIntIntMapOf()
+    private val codeToSourceToLine = mutableIntIntMapOf()
 
     // These 3 fields collect method scope data. They are reset when a method is added
-    private val methodAddresses = mutableMapOf<Int, Int>()
-    private val methodJumps = mutableListOf<Pair<Int, Int>>()
+    private val methodAddresses = mutableIntIntMapOf()
+    private val methodJumps = mutableListOf<IntIntPair>()
     private var lastMethodLineNumber: Int = -1
 
     fun startClass(clazz: Class) {
@@ -71,7 +74,8 @@ class CodeBuilder(private val codeStyle: CodeStyle) {
 
     fun endMethod() {
         methodJumps.forEach { (line, address) ->
-            val targetLine = methodAddresses[address] ?: return@forEach
+            val targetLine = methodAddresses.getOrDefault(address, -1)
+            if (targetLine == -1) return@forEach
             jumps[line] = targetLine
         }
         methodAddresses.clear()
@@ -85,7 +89,7 @@ class CodeBuilder(private val codeStyle: CodeStyle) {
         sb.append("  ".repeat(codeStyle.indent))
         methodAddresses[instruction.address] = line
         if (instruction.jumpAddress != null) {
-            methodJumps.add(line to instruction.jumpAddress)
+            methodJumps.add(IntIntPair(line, instruction.jumpAddress))
         }
         val lineNumber = instruction.lineNumber
         if (lineNumber != null) {

diff --git a/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/CodeTextArea.kt b/src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/CodeTextArea.kt
@@ -62,6 +62,7 @@ class CodeTextArea(
                 override fun mouseClicked(event: MouseEvent) {
                     val codeLine = getLineOfOffset(viewToModel2D(event.point))
                     val line = code?.getSourceLine(codeLine) ?: return
+                    if (line == -1) return
                     sourceTextArea.gotoLine(this@CodeTextArea, line - 1)
                 }
             })
@@ -76,6 +77,7 @@ class CodeTextArea(
 
     fun gotoSourceLine(sourceLine: Int) {
         val line = code?.getCodeLine(sourceLine + 1) ?: return
+        if (line == -1) return
         caretPosition = getLineStartOffset(line.coerceIn(0 until lineCount))
         centerCaretInView()
     }
@@ -154,7 +156,8 @@ class CodeTextArea(
         val oldJumpOffsets = jumpOffsets
         try {
             jumpOffsets = null
-            val dstLine = codeModel.getJumpTargetOfLine(line) ?: return
+            val dstLine = codeModel.getJumpTargetOfLine(line)
+            if (dstLine == -1) return
 
             val srcOffset = getLineStartOffset(line) + getLine(line).countPadding()
             val dstOffset = getLineStartOffset(dstLine) + getLine(dstLine).countPadding()