8309136: [JVMCI] add -XX:+UseGraalJIT flag

Reviewed-by: dholmes, kvn

Author: Doug Simon

src/hotspot/share/compiler/compilerDefinitions.cpp

@@ -545,7 +545,7 @@ bool CompilerConfig::check_args_consistency(bool status) {
       FLAG_SET_DEFAULT(SegmentedCodeCache, false);
     }
 #if INCLUDE_JVMCI
-    if (EnableJVMCI) {
+    if (EnableJVMCI || UseJVMCICompiler) {
       if (!FLAG_IS_DEFAULT(EnableJVMCI) || !FLAG_IS_DEFAULT(UseJVMCICompiler)) {
         warning("JVMCI Compiler disabled due to -Xint.");
       }

src/hotspot/share/jvmci/jvmci_globals.cpp

@@ -71,6 +71,7 @@ bool JVMCIGlobals::check_jvmci_flags_are_consistent() {
   JVMCI_FLAG_CHECKED(UseJVMCICompiler)
   JVMCI_FLAG_CHECKED(EnableJVMCI)
   JVMCI_FLAG_CHECKED(EnableJVMCIProduct)
+  JVMCI_FLAG_CHECKED(UseGraalJIT)
 
   CHECK_NOT_SET(BootstrapJVMCI,   UseJVMCICompiler)
   CHECK_NOT_SET(PrintBootstrap,   UseJVMCICompiler)
@@ -164,7 +165,7 @@ bool JVMCIGlobals::check_jvmci_flags_are_consistent() {
 }
 
 // Convert JVMCI flags from experimental to product
-bool JVMCIGlobals::enable_jvmci_product_mode(JVMFlagOrigin origin) {
+bool JVMCIGlobals::enable_jvmci_product_mode(JVMFlagOrigin origin, bool use_graal_jit) {
   const char *JVMCIFlags[] = {
     "EnableJVMCI",
     "EnableJVMCIProduct",
@@ -201,6 +202,12 @@ bool JVMCIGlobals::enable_jvmci_product_mode(JVMFlagOrigin origin) {
   if (JVMFlagAccess::set_bool(jvmciEnableFlag, &value, origin) != JVMFlag::SUCCESS) {
     return false;
   }
+  if (use_graal_jit) {
+    JVMFlag *useGraalJITFlag = JVMFlag::find_flag("UseGraalJIT");
+    if (JVMFlagAccess::set_bool(useGraalJITFlag, &value, origin) != JVMFlag::SUCCESS) {
+      return false;
+    }
+  }
 
   // Effect of EnableJVMCIProduct on changing defaults of EnableJVMCI
   // and UseJVMCICompiler is deferred to check_jvmci_flags_are_consistent

src/hotspot/share/jvmci/jvmci_globals.hpp

@@ -48,6 +48,11 @@ class fileStream;
   product(bool, EnableJVMCI, false, EXPERIMENTAL,                           \
           "Enable JVMCI")                                                   \
                                                                             \
+  product(bool, UseGraalJIT, false, EXPERIMENTAL,                           \
+          "Select the Graal JVMCI compiler. This is an alias for: "         \
+          "  -XX:+EnableJVMCIProduct "                                      \
+          "  -Djvmci.Compiler=graal ")                                      \
+                                                                            \
   product(bool, EnableJVMCIProduct, false, EXPERIMENTAL,                    \
           "Allow JVMCI to be used in product mode. This alters a subset of "\
           "JVMCI flags to be non-experimental, defaults UseJVMCICompiler "  \
@@ -185,7 +190,7 @@ class JVMCIGlobals {
   static bool check_jvmci_flags_are_consistent();
 
   // Convert JVMCI experimental flags to product
-  static bool enable_jvmci_product_mode(JVMFlagOrigin);
+  static bool enable_jvmci_product_mode(JVMFlagOrigin origin, bool use_graal_jit);
 
   // Returns true iff the GC fully supports JVMCI.
   static bool gc_supports_jvmci();

src/hotspot/share/runtime/arguments.cpp

@@ -2827,28 +2827,42 @@ jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, bool* patch_m
         return JNI_ERR;
 #endif // INCLUDE_MANAGEMENT
 #if INCLUDE_JVMCI
-    } else if (match_option(option, "-XX:-EnableJVMCIProduct")) {
+    } else if (match_option(option, "-XX:-EnableJVMCIProduct") || match_option(option, "-XX:-UseGraalJIT")) {
       if (EnableJVMCIProduct) {
         jio_fprintf(defaultStream::error_stream(),
-                  "-XX:-EnableJVMCIProduct cannot come after -XX:+EnableJVMCIProduct\n");
+                  "-XX:-EnableJVMCIProduct or -XX:-UseGraalJIT cannot come after -XX:+EnableJVMCIProduct or -XX:+UseGraalJIT\n");
         return JNI_EINVAL;
       }
-    } else if (match_option(option, "-XX:+EnableJVMCIProduct")) {
-      // Just continue, since "-XX:+EnableJVMCIProduct" has been specified before
+    } else if (match_option(option, "-XX:+EnableJVMCIProduct") || match_option(option, "-XX:+UseGraalJIT")) {
+      bool use_graal_jit = match_option(option, "-XX:+UseGraalJIT");
+      if (use_graal_jit) {
+        const char* jvmci_compiler = get_property("jvmci.Compiler");
+        if (jvmci_compiler != nullptr) {
+          if (strncmp(jvmci_compiler, "graal", strlen("graal")) != 0) {
+            jio_fprintf(defaultStream::error_stream(),
+              "Value of jvmci.Compiler incompatible with +UseGraalJIT: %s", jvmci_compiler);
+            return JNI_ERR;
+          }
+        } else if (!add_property("jvmci.Compiler=graal")) {
+            return JNI_ENOMEM;
+        }
+      }
+
+      // Just continue, since "-XX:+EnableJVMCIProduct" or "-XX:+UseGraalJIT" has been specified before
       if (EnableJVMCIProduct) {
         continue;
       }
       JVMFlag *jvmciFlag = JVMFlag::find_flag("EnableJVMCIProduct");
       // Allow this flag if it has been unlocked.
       if (jvmciFlag != nullptr && jvmciFlag->is_unlocked()) {
-        if (!JVMCIGlobals::enable_jvmci_product_mode(origin)) {
+        if (!JVMCIGlobals::enable_jvmci_product_mode(origin, use_graal_jit)) {
           jio_fprintf(defaultStream::error_stream(),
             "Unable to enable JVMCI in product mode");
           return JNI_ERR;
         }
       }
       // The flag was locked so process normally to report that error
-      else if (!process_argument("EnableJVMCIProduct", args->ignoreUnrecognized, origin)) {
+      else if (!process_argument(use_graal_jit ? "UseGraalJIT" : "EnableJVMCIProduct", args->ignoreUnrecognized, origin)) {
         return JNI_EINVAL;
       }
 #endif // INCLUDE_JVMCI

test/hotspot/jtreg/compiler/jvmci/TestEnableJVMCIProduct.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 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
@@ -50,6 +50,14 @@ static class Expectation {
     }
 
     public static void main(String[] args) throws Exception {
+        if (args.length != 0) {
+            // Called as subprocess. Print system properties named by
+            // `args` and then exit.
+            for (String arg : args) {
+                System.out.printf("%s=%s%n", arg, System.getProperty(arg));
+            }
+            return;
+        }
         // Test EnableJVMCIProduct without any other explicit JVMCI option
         test("-XX:-PrintWarnings",
             new Expectation("EnableJVMCI", "true", "default"),
@@ -67,24 +75,33 @@ public static void main(String[] args) throws Exception {
             new Expectation("EnableJVMCI", "false", "command line"),
             new Expectation("UseJVMCICompiler", "false", "default"));
         test("-XX:+EnableJVMCIProduct",
-            new Expectation("EnableJVMCIProduct", "true", "command line"),
+            new Expectation("EnableJVMCIProduct", "true", "(?:command line|jimage)"),
             new Expectation("EnableJVMCI", "true", "default"),
             new Expectation("UseJVMCICompiler", "true", "default"));
     }
 
     static void test(String explicitFlag, Expectation... expectations) throws Exception {
-        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
-            "-XX:+UnlockExperimentalVMOptions", "-XX:+EnableJVMCIProduct", "-XX:-UnlockExperimentalVMOptions",
-            explicitFlag,
-            "-XX:+PrintFlagsFinal", "-version");
-        OutputAnalyzer output = new OutputAnalyzer(pb.start());
-        for (Expectation expectation : expectations) {
-            output.stdoutShouldMatch(expectation.pattern);
-        }
-        if (output.getExitValue() != 0) {
-            // This should only happen when JVMCI compilation is requested and the VM has no
-            // JVMCI compiler (e.g. Graal is not included in the build)
-            output.stdoutShouldMatch("No JVMCI compiler found");
+        String[] flags = {"-XX:+EnableJVMCIProduct", "-XX:+UseGraalJIT"};
+        String cwd = System.getProperty("user.dir");
+        for (String flag : flags) {
+            ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
+                "-XX:+UnlockExperimentalVMOptions", flag, "-XX:-UnlockExperimentalVMOptions",
+                explicitFlag,
+                "-XX:+PrintFlagsFinal",
+                "--class-path=" + System.getProperty("java.class.path"),
+                "TestEnableJVMCIProduct", "jvmci.Compiler");
+            OutputAnalyzer output = new OutputAnalyzer(pb.start());
+            for (Expectation expectation : expectations) {
+                output.stdoutShouldMatch(expectation.pattern);
+            }
+            if (flag.equals("-XX:+UseGraalJIT")) {
+                output.shouldContain("jvmci.Compiler=graal");
+            }
+            if (output.getExitValue() != 0) {
+                // This should only happen when JVMCI compilation is requested and the VM has no
+                // JVMCI compiler (e.g. Graal is not included in the build)
+                output.stdoutShouldMatch("No JVMCI compiler found");
+            }
         }
     }
 }