[K/N] Extracted some common BitSet utils

compiler/backend-common/src/org/jetbrains/kotlin/backend/common/BitSetUtil.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.backend.common
+
+import java.util.*
+
+fun BitSet.copy() = BitSet(this.size()).apply { this.or(this@copy) }
+
+inline fun BitSet.forEachBit(block: (Int) -> Unit) {
+    var i = -1
+    while (true) {
+        i = nextSetBit(i + 1)
+        if (i < 0) break
+        block(i)
+    }
+}

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/optimizations/CallGraphBuilder.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.backend.konan.optimizations
 
+import org.jetbrains.kotlin.backend.common.forEachBit
 import org.jetbrains.kotlin.backend.common.pop
 import org.jetbrains.kotlin.backend.common.push
 import org.jetbrains.kotlin.backend.konan.DirectedGraph

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/optimizations/DevirtualizationAnalysis.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.backend.konan.optimizations
 
+import org.jetbrains.kotlin.backend.common.copy
+import org.jetbrains.kotlin.backend.common.forEachBit
 import org.jetbrains.kotlin.backend.common.pop
 import org.jetbrains.kotlin.backend.common.push
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
@@ -35,17 +37,6 @@ import org.jetbrains.kotlin.name.Name
 import java.util.*
 import kotlin.collections.ArrayList
 
-inline fun BitSet.forEachBit(block: (Int) -> Unit) {
-    var i = -1
-    while (true) {
-        i = nextSetBit(i + 1)
-        if (i < 0) break
-        block(i)
-    }
-}
-
-fun BitSet.copy() = BitSet(this.size()).apply { this.or(this@copy) }
-
 // Devirtualization analysis is performed using Variable Type Analysis algorithm.
 // See http://web.cs.ucla.edu/~palsberg/tba/papers/sundaresan-et-al-oopsla00.pdf for details.
 internal object DevirtualizationAnalysis {

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/optimizations/StaticInitializersOptimization.kt

@@ -5,6 +5,7 @@
 
 package org.jetbrains.kotlin.backend.konan.optimizations
 
+import org.jetbrains.kotlin.backend.common.copy
 import org.jetbrains.kotlin.backend.common.lower.createIrBuilder
 import org.jetbrains.kotlin.backend.common.lower.irBlock
 import org.jetbrains.kotlin.backend.konan.Context