RFR: 8145270: Need to eagerly initialize JVMCI compiler under -Xcomp

[Christian Thalinger]

Alright, I’ll push that.

> On Dec 14, 2015, at 12:46 PM, Doug Simon <doug.simon at oracle.com> wrote:
> 
> I was tempted to do that myself but opted for keeping the patch minimal. However, the solution that propagates the exception is obviously better.
> 
>> On 14 Dec 2015, at 22:24, Christian Thalinger <christian.thalinger at oracle.com> wrote:
>> 
>> 
>>> On Dec 13, 2015, at 11:49 AM, Doug Simon <doug.simon at oracle.com> wrote:
>>> 
>>> In blocking compilation mode (i.e., -UseInterpreter), certain compilations are forced to be non-blocking if a JVMCI compiler is being used (i.e., +UseJVMCICompiler). This is to prevent deadlocks than can occur between an application thread and a JVMCI compiler thread. One condition for forcing a compilation to be non-blocking is if the JVMCI compiler not yet initialized. This is problematic for tests that attempt to force a method to be compiled by JVMCI (e.g., -XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI -XX:+UseJVMCICompiler -XX:-TieredCompilation -Xcomp -XX:CompileCommand=compileonly,Tester_*::*). If the test is small enough, JVMCI initialization (which is lazy) may still be executing when the test methods are scheduled to be compiled. 
>>> 
>>> The solution is to make JVMCI compiler initialization eager in blocking compilation mode.
>>> 
>>> https://bugs.openjdk.java.net/browse/JDK-8145270
>>> http://cr.openjdk.java.net/~dnsimon/8145270/
>> 
>> Looks good.  The only comment I have is at that point in initialization we can handle exceptions already and I think we should.  This gives us even useful stack traces:
>> 
>> Error occurred during initialization of VM
>> java.lang.Error: just testing
>> 	at jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.getCompiler(HotSpotJVMCIRuntime.java:181)
>> 
>> Here is the updated patch:
>> 
>> diff -r d84bd22ab531 src/share/vm/compiler/compileBroker.cpp
>> --- a/src/share/vm/compiler/compileBroker.cpp	Wed Dec 09 14:54:40 2015 +0100
>> +++ b/src/share/vm/compiler/compileBroker.cpp	Mon Dec 14 12:20:18 2015 -1000
>> @@ -56,6 +56,7 @@
>> #if INCLUDE_JVMCI
>> #include "jvmci/jvmciCompiler.hpp"
>> #include "jvmci/jvmciRuntime.hpp"
>> +#include "jvmci/jvmciJavaClasses.hpp"
>> #include "runtime/vframe.hpp"
>> #endif
>> #ifdef COMPILER2
>> @@ -498,7 +499,7 @@ CompilerCounters::CompilerCounters() {
>> // CompileBroker::compilation_init
>> //
>> // Initialize the Compilation object
>> -void CompileBroker::compilation_init() {
>> +void CompileBroker::compilation_init(TRAPS) {
>>  _last_method_compiled[0] = '\0';
>> 
>>  // No need to initialize compilation system if we do not use it.
>> @@ -529,6 +530,17 @@ void CompileBroker::compilation_init() {
>>      } else {
>>        c1_count = JVMCIHostThreads;
>>      }
>> +
>> +      if (!UseInterpreter) {
>> +        // Force initialization of JVMCI compiler otherwise JVMCI
>> +        // compilations will not block until JVMCI is initialized
>> +        ResourceMark rm;
>> +        TempNewSymbol getCompiler = SymbolTable::new_symbol("getCompiler", CHECK);
>> +        TempNewSymbol sig = SymbolTable::new_symbol("()Ljdk/vm/ci/runtime/JVMCICompiler;", CHECK);
>> +        Handle jvmciRuntime = JVMCIRuntime::get_HotSpotJVMCIRuntime(CHECK);
>> +        JavaValue result(T_OBJECT);
>> +        JavaCalls::call_virtual(&result, jvmciRuntime, HotSpotJVMCIRuntime::klass(), getCompiler, sig, CHECK);
>> +      }
>>    }
>>  }
>> #endif // INCLUDE_JVMCI
>> diff -r d84bd22ab531 src/share/vm/compiler/compileBroker.hpp
>> --- a/src/share/vm/compiler/compileBroker.hpp	Wed Dec 09 14:54:40 2015 +0100
>> +++ b/src/share/vm/compiler/compileBroker.hpp	Mon Dec 14 12:20:18 2015 -1000
>> @@ -276,7 +276,7 @@ public:
>>    CompileQueue *q = compile_queue(comp_level);
>>    return q != NULL ? q->size() : 0;
>>  }
>> -  static void compilation_init();
>> +  static void compilation_init(TRAPS);
>>  static void init_compiler_thread_log();
>>  static nmethod* compile_method(const methodHandle& method,
>>                                 int osr_bci,
>> diff -r d84bd22ab531 src/share/vm/runtime/thread.cpp
>> --- a/src/share/vm/runtime/thread.cpp	Wed Dec 09 14:54:40 2015 +0100
>> +++ b/src/share/vm/runtime/thread.cpp	Mon Dec 14 12:20:18 2015 -1000
>> @@ -3628,7 +3628,7 @@ jint Threads::create_vm(JavaVMInitArgs* 
>> 
>>  // initialize compiler(s)
>> #if defined(COMPILER1) || defined(COMPILER2) || defined(SHARK) || INCLUDE_JVMCI
>> -  CompileBroker::compilation_init();
>> +  CompileBroker::compilation_init(CHECK_JNI_ERR);
>> #endif
>> 
>>  // Pre-initialize some JSR292 core classes to avoid deadlock during class loading.
>> 
>