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A colleague commented to me that you were<br>
perhaps looking for the JIT'ed code that does<br>
the bump allocations. In which case you will need<br>
to find something different than allocate_from_tlab()<br>
which would be used by the interpreter.<br>
<br>
<br>
On 11/18/10 10:16, Jon Masamitsu wrote:
<blockquote cite="mid:4CE56D68.6080507@oracle.com" type="cite">
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<br>
<br>
On 11/18/10 09:19, Brain Damage wrote:
<blockquote cite="mid:551909.83135.qm@web112320.mail.gq1.yahoo.com"
type="cite">
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<div>Hello,</div>
<div> </div>
<div>I am trying to do some modifications in the allocation process
of 'external' objects i.e. objects allocated using 'new' by any java
program.</div>
<div>As written in the whitepaper, JVM employs the fast allocation
or
'Bump a pointer' technique for allocating external objects.</div>
<div><br>
</div>
<div>I am not able to find the entry point of the 'new' keyword
i.e.
what functions are called when it sees the new keyword in a java
program.</div>
<div>My initial suspect was JRT_ENTRY(...) macro in the
runtime.cpp
file, where they have matched 'new_instance_java' with
'new_instance_C'.</div>
<div>I tried to follow the functions called by this macro i.e.
instanceKlass::cast(klass)->allocate_instance(THREAD);</div>
<div>Although it did take me to some object allocation but I am not
sure if this is the process used to allocate java objects.</div>
<div>It seems this process is used by the JVM to allocate it's
internal runtime objects to build the environment.</div>
</div>
</blockquote>
<br>
I think you have actually found the code that you are seeking. Follow
the calls<br>
from allocate_instance() down to
CollectedHeap::common_mem_allocate_noinit()<br>
and in that method look at CollectedHeap::allocate_from_tlab() for the
"bump"<br>
allocation.<br>
<blockquote cite="mid:551909.83135.qm@web112320.mail.gq1.yahoo.com"
type="cite">
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style="font-family: 'times new roman','new york',times,serif; font-size: 12pt;">
<div><br>
</div>
<div>I don't know a whole lot about jvm, this is just what I could
make out by looking at the code.</div>
<div><br>
</div>
<div>Please help me find the definition new.</div>
<div><br>
</div>
<div>Thanks,</div>
<div><br>
</div>
<div>Yogesh </div>
</div>
<br>
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