Default method resolution question

[Vladimir Ivanov]

David,

It's in rt.jar.

Best regards,
Vladimir Ivanov

On 9/16/13 3:51 PM, David Holmes wrote:
> Hi Vladimir,
>
> I don't know if it would make any difference but is that the TreeSet
> from rt.jar or alt-rt.jar ?
>
> David
>
> On 16/09/2013 9:39 PM, Vladimir Ivanov wrote:
>> Hi,
>>
>> I hit an assert when doing CHA for a default method during
>> JIT-compilation:
>> #  Internal Error (src/share/vm/code/dependencies.cpp:1411)
>> #  assert(wf.check_method_context(ctxk, m)) failed: proper context
>>
>> Call stack:
>> Dependencies::find_unique_concrete_method
>> ciMethod::find_monomorphic_target
>> Compile::optimize_inlining
>> Compile::optimize_virtual_call
>> Parse::do_call
>> ...
>>
>> What does check_method_context do it resolves the method again and then
>> do pointer comparison to check that result it the same. And it doesn't
>> work for default methods:
>>   Dependency method not found in the associated context:
>>    context = javasoft.sqe.tests.api.java.util.TreeSet.SharedData$1
>>    method =  java.util.TreeSet::parallelStream
>>    found =  java.util.TreeSet::parallelStream
>>
>> My main suspicion is that the problem is in check_method_context (the
>> check is imprecise and already has a number of exceptions), but I want
>> to double-check. Does method resolution behavior I see look normal?
>>
>> Here are my observations.
>>
>> Method passed into Dependencies::find_unique_concrete_method:
>> {method}
>>   - this oop:          0xb69eab58
>>   - method holder:     'java/util/TreeSet'
>>   - constants:         0xb69eacd8 constant pool [305] {0xb69eacdc} for
>> 'java/util/TreeSet' cache=0xb69eb2b8
>>   - access:            0x80001041  public volatile synthetic
>>   - name:              'parallelStream'
>>   - signature:         '()Ljava/util/stream/Stream;'
>>   - max stack:         2
>>   - max locals:        1
>>   - size of params:    1
>>   - method size:       14
>>   - highest level:     4
>>   - vtable index:      22
>>   - i2i entry:         0xfa00b940
>>   - adapters:          AHE at 0x081982ac: 0xa0000000 i2c: 0xfa0aaec0 c2i:
>> 0xfa0aaf49 c2iUV: 0xfa0aaf28
>>   - compiled entry     0xfa1704ec
>>   - code size:         5
>>   - code start:        0xb69eab44
>>   - code end (excl):   0xb69eab49
>>   - method data:       0xb6806b10
>>   - checked ex length: 0
>>   - localvar length:   0
>>   - compiled code: nmethod 584533  988 java.util.TreeSet::parallelStream
>> (5 bytes)
>>
>> Method resolved in check_method_context:
>> {method}
>>   - this oop:          0xb69ea978
>>   - method holder:     'java/util/TreeSet'
>>   - constants:         0xb69eacd8 constant pool [305] {0xb69eacdc} for
>> 'java/util/TreeSet' cache=0xb69eb2b8
>>   - access:            0x1041  public volatile synthetic
>>   - name:              'parallelStream'
>>   - signature:         'Ljava/util/stream/Stream'
>>   - max stack:         2
>>   - max locals:        1
>>   - size of params:    1
>>   - method size:       14
>>   - vtable index:      22
>>   - i2i entry:         0xfa00b940
>>   - adapters:          AHE at 0x081982ac: 0xa0000000 i2c: 0xfa0aaec0 c2i:
>> 0xfa0aaf49 c2iUV: 0xfa0aaf28
>>   - compiled entry     0xfa0aaf49
>>   - code size:         5
>>   - code start:        0xb69ea964
>>   - code end (excl):   0xb69ea969
>>   - method data:       0xb6584270
>>   - checked ex length: 0
>>   - localvar length:   0
>>
>> Class hierarchy:
>> javasoft.sqe.tests.api.java.util.TreeSet.SharedData$1 extends
>> java.util.TreeSet<E>
>>
>> java.util.TreeSet<E> extends java.util.AbstractSet<E>
>>               implements java.util.NavigableSet<E>,
>>                  java.lang.Cloneable,
>>                  java.io.Serializable
>>
>> public interface Collection<E> extends Iterable<E> {
>>      default Stream<E> parallelStream() { ... }
>>
>> Original method pointer is acquired through ciMethod::resolve_invoke
>> call.
>>
>> resolved_method && CallInfo from LinkResolver::resolve_virtual_call:
>>
>> (dbx) print resolved_method
>> resolved_method = {
>>      _value  = 0xb69ea978   <=============
>>      _thread = 0x8232c00
>> }
>>
>> (dbx) print result
>> result = {
>>      _resolved_klass       = {
>>          _value = 0xb69ea618
>>      }
>>      _selected_klass       = {
>>          _value = 0xb69f3bb0
>>      }
>>      _resolved_method      = {
>>          _value  = 0xb69ea978 <===========
>>          _thread = 0x8232c00
>>      }
>>      _selected_method      = {
>>          _value  = 0xb69eab58 <===========
>>          _thread = 0x8232c00
>>      }
>>      _vtable_index         = 22
>>      _resolved_appendix    = {
>>          _handle = (nil)
>>      }
>>      _resolved_method_type = {
>>          _handle = (nil)
>>      }
>> }
>>
>> _resolved_method is the same as computed in check_method_context.
>>
>> _selected_method is loaded from vtable at linkResolver.cpp:943:
>>      selected_method = methodHandle(THREAD,
>> inst->method_at_vtable(vtable_index));
>>
>> Best regards,
>> Vladimir Ivanov