view agent/doc/cireplay.html @ 20228:f72d8917322a

8050978: Fix bad field access check in C1 and C2 Summary: JCK8 test vm/constantpool/accessControl/accessControl004/accessControl00402m3/accessControl00402m3.html fails with -Xbatch -Xcomp due to bad field access check in C1 and C2. Fix: In ciField::ciField(), just before the canonical holder is stored into the _holder variable (and which is used by ciField::will_link()) perform an additional access check with the holder declared in the class file. If this check fails, store the declared holder instead and ciField::will_link() will bail out compilation for this field later on. Then, the interpreter will throw an PrivilegedAccessException at runtime. Reviewed-by: kvn, vlivanov Contributed-by: andreas.schoesser@sap.com
author goetz
date Fri, 18 Jul 2014 09:04:01 +0200
parents 7b23cb975cf2
children
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<html>
<head>
<title>
Replay
</title>
</head>
<body>

<h1>Compiler replay</h1>
<p>
The compiler replay is a function to repeat the compiling process from a crashed java process in compiled method<br>
This function only exists in debug version of VM
</p>
<h2>Usage</h2>
<pre>
First, use SA to attach to the core file, if succeeded, do
       hsdb&gt; dumpreplaydata &lt;address&gt; | -a | &lt;thread_id&gt; [&gt; replay.txt]
       create file replay.txt, address is address of Method, or nmethod(CodeBlob)
       hsdb&gt; buildreplayjars [all | boot | app]
       create files:
         all:
           app.jar, boot.jar
         boot:
           boot.jar
         app:
           app.jar
       exit SA now.
Second, use the obtained replay text file, replay.txt and jar files, app.jar and boot.jar, using debug version of java
       java -Xbootclasspath/p:boot.jar -cp app.jar -XX:ReplayDataFile=&lt;datafile&gt; -XX:+ReplayCompiles ....
       This will replay the compiling process.

       With ReplayCompiles, the replay will recompile all the methods in app.jar, and in boot.jar to emulate the process in java app.

notes:
       1) Most time, we don't need the boot.jar which is the classes loaded from JDK. It will be only modified when an agent(JVMDI) is running and modifies the classes.
       2) If encounter error as "&lt;flag&gt;" not found, that means the SA is using a VMStructs which is different from the one with corefile. In this case, SA has a utility tool vmstructsdump which is located at agent/src/os/&lt;os&gt;/proc/&lt;os_platform&gt;

       Use this tool to dump VM type library:
       vmstructsdump libjvm.so &gt; &lt;type_name&gt;.db

       set env SA_TYPEDB=&lt;type_name&gt;.db (refer different shell for set envs)