C++ profiles processor: wire up to VM.

C++ profiles processor: wire up to VM.

If 'shell' is compiled with 'cppprofilesprocessor=on' and run
with '--prof' flag, top-down and bottom-up call trees are printed
on shell exit.

Committed: http://code.google.com/p/v8/source/detail?r=4343

[mnaganov (inactive), 2010-03-31 16:08:53]

This change looks big, but it is actually pretty simple: it adds Logger-like
CpuProfiler object which is bound to VM events by PROFILE macro. If v8 is
compiled as usual, PROFILE is just expanded into LOG. If v8 is compiled with
'cppprofilesprocessor', PROFILE also notifies profiles processor. Also, Sampler
platform-specific implementations are modified to report stack samples to the
new implementation.

[Kevin Millikin (Chromium), 2010-04-06 09:10:47]

LGTM.

http://codereview.chromium.org/1582004/diff/1/16
File src/platform-linux.cc (right):

http://codereview.chromium.org/1582004/diff/1/16#newcode735
src/platform-linux.cc:735: TickSample sample_obj, *sample = &sample_obj;
This is probably better as:

TickSample sample_obj;
TickSample* sample = &sample_obj;

Same for the other platform-XXX.cc files.

[mnaganov (inactive), 2010-04-06 10:31:42]

Thanks a lot, Kevin!

http://codereview.chromium.org/1582004/diff/1/16
File src/platform-linux.cc (right):

http://codereview.chromium.org/1582004/diff/1/16#newcode735
src/platform-linux.cc:735: TickSample sample_obj, *sample = &sample_obj;
On 2010/04/06 09:10:47, Kevin Millikin wrote:
> This is probably better as:
> 
> TickSample sample_obj;
> TickSample* sample = &sample_obj;
> 
> Same for the other platform-XXX.cc files.

Done.

[Søren Thygesen Gjesse, 2010-04-06 10:37:43]

http://codereview.chromium.org/1582004/diff/1/16
File src/platform-linux.cc (right):

http://codereview.chromium.org/1582004/diff/1/16#newcode773
src/platform-linux.cc:773: #ifdef ENABLE_CPP_PROFILES_PROCESSOR
If this #ifdef block needed? From above IsVmThread() must be true if
ENABLE_CPP_PROFILES_PROCESSOR is defined.

[mnaganov (inactive), 2010-04-06 11:44:52]

http://codereview.chromium.org/1582004/diff/1/16
File src/platform-linux.cc (right):

http://codereview.chromium.org/1582004/diff/1/16#newcode773
src/platform-linux.cc:773: #ifdef ENABLE_CPP_PROFILES_PROCESSOR
On 2010/04/06 10:37:43, Søren Gjesse wrote:
> If this #ifdef block needed? From above IsVmThread() must be true if
> ENABLE_CPP_PROFILES_PROCESSOR is defined.

Right, not needed actually. I will remove it in my next commit.