Replace AtomicLong.VMSupportsCS8() with a stub (#290)

src/jvm/main/org/jetbrains/kotlinx/lincheck/transformation/LincheckClassVisitor.kt

@@ -58,6 +58,12 @@ internal class LincheckClassVisitor(
         signature: String?,
         exceptions: Array<String>?
     ): MethodVisitor {
+        if (access and ACC_NATIVE != 0 && methodName == "VMSupportsCS8") {
+            // Replace native method VMSupportsCS8 in AtomicLong with our stub.
+            // TODO: remove this code when javaagents are merged.
+            val mv = super.visitMethod(access xor ACC_NATIVE, methodName, desc, signature, exceptions)
+            return VMSupportsCS8MethodGenerator(GeneratorAdapter(mv, access xor ACC_NATIVE, methodName, desc))
+        }
         var mv = super.visitMethod(access, methodName, desc, signature, exceptions)
         if (access and ACC_NATIVE != 0) return mv
         if (transformationMode == STRESS || transformationMode == VERIFICATION) {
@@ -108,6 +114,21 @@ internal class LincheckClassVisitor(
         return mv
     }
 
+    /**
+     * Generates body of a native method `VMSupportsCS8()`.
+     * Native methods in java.util can not be transformed, so we should replace them with stubs.
+     * TODO: remove this code when javaagents are merged.
+     */
+    private class VMSupportsCS8MethodGenerator(val adapter: GeneratorAdapter) : MethodVisitor(ASM_API, null) {
+        override fun visitEnd() = adapter.run {
+            visitCode()
+            push(true) // suppose that we always have CAS for Long
+            returnValue()
+            visitMaxs(1, 0)
+            visitEnd()
+        }
+    }
+
     private class CoroutineCancellabilitySupportMethodTransformer(
         mv: MethodVisitor,
         access: Int,

src/jvm/test/org/jetbrains/kotlinx/lincheck_test/transformation/AtomicLongTest.kt

@@ -0,0 +1,26 @@
+/*
+ * Lincheck
+ *
+ * Copyright (C) 2019 - 2024 JetBrains s.r.o.
+ *
+ * This Source Code Form is subject to the terms of the
+ * Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed
+ * with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+package org.jetbrains.kotlinx.lincheck_test.transformation
+
+import org.jetbrains.kotlinx.lincheck.annotations.Operation
+import org.jetbrains.kotlinx.lincheck_test.*
+import java.util.concurrent.atomic.AtomicLong
+
+/**
+ * Checks that the AtomicLong.VMSupportsCS8() native method
+ * is correctly transformed.
+ */
+class AtomicLongTest : AbstractLincheckTest() {
+    val counter = AtomicLong()
+
+    @Operation
+    fun inc() = counter.incrementAndGet()
+}