Add support for --sun-misc-unsafe-memory-access=

Author: gilles-duboscq

espresso-shared/src/com.oracle.truffle.espresso.classfile/src/com/oracle/truffle/espresso/classfile/JavaVersion.java

@@ -199,6 +199,10 @@ public boolean java23OrEarlier() {
         return version <= 23;
     }
 
+    public boolean java23OrLater() {
+        return version >= 23;
+    }
+
     public boolean java24OrEarlier() {
         return version <= 24;
     }

espresso/src/com.oracle.truffle.espresso.launcher/src/com/oracle/truffle/espresso/launcher/EspressoLauncher.java

@@ -328,11 +328,13 @@ protected List<String> preprocessArguments(List<String> arguments, Map<String, S
                     } else if (arg.startsWith("-Xshare:")) {
                         String value = arg.substring("-Xshare:".length());
                         espressoOptions.put("java.CDS", value);
+                    } else if (arg.startsWith("--sun-misc-unsafe-memory-access")) {
+                        String value = args.getValue(arg, "sun.misc.Unsafe memory access");
+                        espressoOptions.put("java.SunMiscUnsafeMemoryAccess", value);
                     } else if (arg.startsWith("-XX:")) {
                         handleXXArg(arg, unrecognized);
-                    } else
-                    // -Dsystem.property=value
-                    if (arg.startsWith("-D")) {
+                    } else if (arg.startsWith("-D")) {
+                        // -Dsystem.property=value
                         String key = arg.substring("-D".length());
                         int splitAt = key.indexOf("=");
                         String value = "";

espresso/src/com.oracle.truffle.espresso.libjavavm/src/com/oracle/truffle/espresso/libjavavm/Arguments.java

@@ -223,6 +223,9 @@ public static int setupContext(Context.Builder builder, JNIJavaVMInitArgs args,
                     } else if (optionString.startsWith("-Xshare:")) {
                         String value = optionString.substring("-Xshare:".length());
                         builder.option("java.CDS", value);
+                    } else if (optionString.startsWith("--sun-misc-unsafe-memory-access=")) {
+                        String value = optionString.substring("--sun-misc-unsafe-memory-access=".length());
+                        builder.option("java.SunMiscUnsafeMemoryAccess", value);
                     } else if (optionString.startsWith("-XX:")) {
                         handler.handleXXArg(optionString);
                     } else if (optionString.startsWith("--help:")) {

espresso/src/com.oracle.truffle.espresso/src/com/oracle/truffle/espresso/EspressoOptions.java

@@ -749,6 +749,20 @@ public enum XShareOption {
                     usageSyntax = "<duration in ms>") //
     public static final OptionKey<Integer> ThreadRequestGracePeriod = new OptionKey<>(100);
 
+    public enum MemoryAccessOption {
+        allow,
+        warn,
+        debug,
+        deny,
+        defaultValue // undocumented sentinel value
+    }
+
+    @Option(help = "Allow or deny usage of unsupported API sun.misc.Unsafe", //
+                    category = OptionCategory.EXPERT, //
+                    stability = OptionStability.EXPERIMENTAL, //
+                    usageSyntax = "allow|warn|debug|deny") //
+    public static final OptionKey<MemoryAccessOption> SunMiscUnsafeMemoryAccess = new OptionKey<>(MemoryAccessOption.defaultValue);
+
     /**
      * Property used to force liveness analysis to also be applied by the interpreter. For testing
      * purpose only. Use a host property rather than an option. An option would slow interpreter

espresso/src/com.oracle.truffle.espresso/src/com/oracle/truffle/espresso/vm/VM.java

@@ -89,6 +89,7 @@
 import com.oracle.truffle.api.source.SourceSection;
 import com.oracle.truffle.espresso.EspressoLanguage;
 import com.oracle.truffle.espresso.EspressoOptions;
+import com.oracle.truffle.espresso.EspressoOptions.MemoryAccessOption;
 import com.oracle.truffle.espresso.blocking.GuestInterruptedException;
 import com.oracle.truffle.espresso.cds.CDSSupport;
 import com.oracle.truffle.espresso.classfile.ClasspathEntry;
@@ -2545,6 +2546,13 @@ private PropertiesMap buildPropertiesMap() {
             map.setPropertyIfExists("jdk.module.illegal.native.access", options.get(EspressoOptions.IllegalNativeAccess), "IllegalNativeAccess");
         }
 
+        if (getJavaVersion().java23OrLater()) {
+            MemoryAccessOption memoryAccessOption = options.get(EspressoOptions.SunMiscUnsafeMemoryAccess);
+            if (memoryAccessOption != MemoryAccessOption.defaultValue) {
+                map.set("sun.misc.unsafe.memory.access", memoryAccessOption.name(), "SunMiscUnsafeMemoryAccess");
+            }
+        }
+
         // Applications expect different formats e.g. 1.8 vs. 11
         String specVersion = getJavaVersion().java8OrEarlier()
                         ? "1." + getJavaVersion()