Benchmark Java to/from C string conversions

test/micro/org/openjdk/bench/java/lang/foreign/ToCStringTest.java

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+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package org.openjdk.bench.java.lang.foreign;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Param;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.TearDown;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.lang.foreign.Arena;
+import java.lang.foreign.FunctionDescriptor;
+import java.lang.foreign.Linker;
+import java.lang.foreign.MemorySegment;
+import java.lang.foreign.MemorySegment.Scope;
+import java.lang.foreign.SegmentAllocator;
+import java.lang.invoke.MethodHandle;
+import java.util.concurrent.TimeUnit;
+
+import static java.lang.foreign.ValueLayout.JAVA_BYTE;
+
+@BenchmarkMode(Mode.AverageTime)
+@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@State(org.openjdk.jmh.annotations.Scope.Thread)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@Fork(value = 3, jvmArgsAppend = { "--enable-native-access=ALL-UNNAMED" })
+public class ToCStringTest extends CLayouts {
+
+    @Param({"5", "20", "100", "200"})
+    public int size;
+    public String str;
+
+    static {
+        System.loadLibrary("ToCString");
+    }
+
+    static final MethodHandle STRLEN;
+
+    static {
+        Linker abi = Linker.nativeLinker();
+        STRLEN = abi.downcallHandle(abi.defaultLookup().find("strlen").get(),
+                FunctionDescriptor.of(C_INT, C_POINTER));
+    }
+
+    @Setup
+    public void setup() {
+        str = makeString(size);
+    }
+
+    @Benchmark
+    public long jni_writeString() throws Throwable {
+        return writeString(str);
+    }
+
+    @Benchmark
+    public MemorySegment panama_writeString() throws Throwable {
+        Arena arena = Arena.ofConfined();
+        MemorySegment segment = arena.allocateFrom(str);
+        arena.close();
+        return segment;
+    }
+
+    static native long writeString(String str);
+
+    static String makeString(int size) {
+        String lorem = """
+                Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et
+                 dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip
+                 ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu
+                 fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt
+                 mollit anim id est laborum.
+                """;
+        return lorem.substring(0, size);
+    }
+}

test/micro/org/openjdk/bench/java/lang/foreign/ToJavaStringTest.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package org.openjdk.bench.java.lang.foreign;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Param;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+
+import java.lang.foreign.Arena;
+import java.lang.foreign.MemorySegment;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
+@State(Scope.Benchmark)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@Fork(value = 3, jvmArgsAppend = {"--enable-native-access=ALL-UNNAMED", "--enable-preview"})
+public class ToJavaStringTest {
+
+    private MemorySegment strSegment;
+
+    @Param({"5", "20", "100", "200"})
+    int size;
+
+    static {
+        System.loadLibrary("ToJavaString");
+    }
+
+    @Setup
+    public void setup() {
+        var arena = Arena.ofAuto();
+        strSegment = arena.allocateFrom(LOREM.substring(0, size));
+    }
+
+    @Benchmark
+    public String panama_readString() {
+        return strSegment.getString(0);
+    }
+
+    @Benchmark
+    public String jni_readString() {
+        return readString(strSegment.address());
+    }
+
+    static native String readString(long addr);
+
+    static String LOREM = """
+                Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et
+                 dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip
+                 ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu
+                 fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt
+                 mollit anim id est laborum.
+                """;
+
+}

test/micro/org/openjdk/bench/java/lang/foreign/libToCString.c

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+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include <jni.h>
+#include <stdlib.h>
+#include <string.h>
+
+JNIEXPORT jlong JNICALL Java_org_openjdk_bench_java_lang_foreign_ToCStringTest_writeString(JNIEnv *const env, const jclass cls, const jstring text) {
+    const char *str = (*env)->GetStringUTFChars(env, text, NULL);
+    jlong addr = (jlong)(void*)str;
+    (*env)->ReleaseStringUTFChars(env, text, str);
+    return addr;
+}

test/micro/org/openjdk/bench/java/lang/foreign/libToJavaString.c

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include <jni.h>
+#include <stdlib.h>
+#include <string.h>
+
+JNIEXPORT jstring JNICALL Java_org_openjdk_bench_java_lang_foreign_ToJavaStringTest_readString(JNIEnv *const env, const jclass cls, jlong addr) {
+    return (*env)->NewStringUTF(env, (char*)(void*)addr);
+}