spring-loaded doesn't work with JVMCI

[jtulach]

Java Virtual Machine Compiler Interface is coming to JDK. It has already been integrated into JDK9 and there are backports to JDK8 as well (download from OTN). However the spring-loaded project doesn't work with the JVMCI builds. Download the JVMCI JDK and try:

 ~/bin/labs1.8.0/bin/java -XX:+BootstrapJVMCI -XX:+UseJVMCICompiler -javaagent:springloaded-1.2.6.RELEASE.jar -noverify -version
Bootstrapping JVMCIjava.lang.NoClassDefFoundError: org/springsource/loaded/ri/ReflectiveInterceptor
        at jdk.vm.ci.hotspot.UnsafeAccess.initUnsafe(UnsafeAccess.java:43)
        at jdk.vm.ci.hotspot.UnsafeAccess.<clinit>(UnsafeAccess.java:34)
        at jdk.vm.ci.hotspot.HotSpotResolvedJavaMethodImpl.getHolder(HotSpotResolvedJavaMethodImpl.java:87)
        at jdk.vm.ci.hotspot.HotSpotResolvedJavaMethodImpl.fromMetaspace(HotSpotResolvedJavaMethodImpl.java:104)

This pull request fixes the problem by not creating a TypeRegistry for classloaders that don't see the application class path like JVMCI classloader & co.

[jtulach]

I've created this PR a year ago and there hasn't been a single reply! That is partially explainable as I was asking people to download a special JDK - however the situation is different today. As @chrisseaton wrote in his Understanding How Graal Works - the Graal compiler is part of standard JDK9. I hope that might increase your motivation to accept my fix.

[jtulach]

To reproduce: get JDK9, my version is:

$ /usr/lib/jvm/java-9-oracle/bin/java --version
java 9.0.1
Java(TM) SE Runtime Environment (build 9.0.1+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.1+11, mixed mode)

and run any long running computation with springloaded.jar agent and following options: -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI -XX:+UseJVMCICompiler. For my own testing purposes I used the Sieve of Eratosthenes, but any other long running application will do. If I run with 1.2.6-RELEASE agent, I get bunch of exceptions from the Graal compiler (as it is using completely isolated classloaders that don't see the agent classes):

$ /usr/lib/jvm/java-9-oracle/bin/java -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI -XX:+UseJVMCICompiler -Dgraal.PrintCompilation=true -javaagent:/springloaded-1.2.6/springloaded.jar -Xverify:none -jar java/algorithm/target/sieve-algorithm-1.0-SNAPSHOT.jar
Computed 97 primes in 1 ms. Last one is 509
Computed 194 primes in 1 ms. Last one is 1181
Computed 388 primes in 2 ms. Last one is 2677
Computed 776 primes in 2 ms. Last one is 5897
Computed 1552 primes in 3 ms. Last one is 13033
Computed 3104 primes in 4 ms. Last one is 28541
Computed 6208 primes in 7 ms. Last one is 61687
Computed 12416 primes in 14 ms. Last one is 133033
Computed 24832 primes in 36 ms. Last one is 284831
Nov 24, 2017 5:13:51 PM org.springsource.loaded.agent.SpringLoadedPreProcessor preProcess
SEVERE: Unexpected problem transforming call sites
java.lang.IllegalArgumentException
        at sl.org.objectweb.asm.ClassReader.<init>(Unknown Source)
        at sl.org.objectweb.asm.ClassReader.<init>(Unknown Source)
        at org.springsource.loaded.MethodInvokerRewriter.rewrite(MethodInvokerRewriter.java:345)
        at org.springsource.loaded.MethodInvokerRewriter.rewrite(MethodInvokerRewriter.java:99)
        at org.springsource.loaded.TypeRegistry.methodCallRewriteUseCacheIfAvailable(TypeRegistry.java:1002)
        at org.springsource.loaded.agent.SpringLoadedPreProcessor.preProcess(SpringLoadedPreProcessor.java:361)
        at org.springsource.loaded.agent.ClassPreProcessorAgentAdapter.transform(ClassPreProcessorAgentAdapter.java:107)
        at java.instrument/java.lang.instrument.ClassFileTransformer.transform(ClassFileTransformer.java:246)
        at java.instrument/sun.instrument.TransformerManager.transform(TransformerManager.java:188)
        at java.instrument/sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:550)
        at java.base/java.lang.ClassLoader.defineClass2(Native Method)

with my patch, I can successfully execute the same command and even see that the Graal compiler does its compilations:

$ /usr/lib/jvm/java-9-oracle/bin/java -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI -XX:+UseJVMCICompiler -Dgraal.PrintCompilation=true -javaagent:/spring-loaded/springloaded/build/libs/springloaded-1.2.9.BUILD-SNAPSHOT.jar -Xverify:none -jar java/algorithm/target/sieve-algorithm-1.0-SNAPSHOT.jar 
134    JVMCI Ljava/lang/StringLatin1;                                               hashCode                                      ([B)I                                              (OSR@10) ...
135    JVMCI Ljava/lang/String;                                                     coder                                         ()B                                                ...
Computed 49664 primes in 104 ms. Last one is 607417
135    JVMCI                                                                                                                                                                         |  334ms    15B    63B 10171kB
468    JVMCI Lorg/apidesign/demo/sieve/eratosthenes/Filter;                         acceptAndAdd                                  (I)Z                                               ...
134    JVMCI                                                                                                                                                                         |  345ms    42B   314B  9823kB
419    JVMCI Ljdk/internal/jimage/ImageStringsReader;                               unmaskedHashCode                              (Ljava/lang/String;I)I                          

Does it make sense to integrate my bugfix now?

[aclement]

Just before I do, have you signed the CLA? https://cla.pivotal.io/sign/pivotal/icla

[jtulach]

Hello Andy, I've just signed the CLA with my apidesign.org address. I hope my PR is now in acceptable state to be merged.

[aclement]

Thanks for confirming, and contributing!