Introduce a RandonNumberGenerator class. Refactor the random/private_random uses in Isolate/Context.

The RandomNumberGenerator is a pseudorandom number generator
with 48-bit state. It is properly seeded using either

(1) the --random-seed if specified, or
(2) the entropy_source function if configured, or
(3) /dev/urandom if available, or
(4) falls back to Time and TimeTicks based seeding.

Each Isolate now contains a RandomNumberGenerator, which replaces
the previous private_random_seed.

Every native context still has its own random_seed. But this random
seed is now properly initialized during bootstrapping,
instead of on-demand initialization. This will allow us to cleanup
and speedup the HRandom implementation quite a lot (this is delayed
for a followup CL)!

Also stop messing with the system rand()/random(), which should
not be done from a library anyway! We probably re-seeded the
libc rand()/random() after the application (i.e. Chrome) already
seeded it (with better entropy than what we used).

Another followup CL will replace the use of the per-isolate
random number generator for the address randomization and
thereby get rid of the Isolate::UncheckedCurrent() usage in
the platform code.

TEST=cctest/test-random-number-generator,cctest/test-random
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/23548024

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16612 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

The reason of that is a number of cons strings in the app.
The app constructs a json string and as a result v8 heap has
a very long chain of cons strings.

Profiler counts all these strings as plain String objects and
assign the content of the strings as node names.

It required O(n^2) time and O(n^2) memory.

Solution: I introduced two new types, kConsString and kSliced string.
They do not use the content of the string for names. So the problem disappeared.

The heap profiler usability problem will be solved on Blink side.

BUG=285770
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/23460027

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16611 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/24087004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16610 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

InstallOptimizedCode aquires ownership on the compilation info and deletes
it on return, tearing down the attached zone.  The OptimizingCompiler
object is a zone object allocated in just that zone, so it also gets
deleted.  Effectively, InstallOptimizedCode cleans up when it's done, so
the OptimizingCompiler object it receives is invalidated afterwards.

R=titzer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23769007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16609 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Add a ResourceConstraint for the embedder to specify that V8 is running on a memory constrained device.

This enables us to specialize certain operations such that we limit memory
usage on low-memory devices, without reducing performance on devices which
are not memory constrained.

BUG=chromium:280984
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/23464022

Patch from Ross McIlroy <rmcilroy@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16608 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/23767009

Patch from Ross McIlroy <rmcilroy@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16607 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=svenpanne@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23581010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16606 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=chromium:236173
R=bmeurer@chromium.org, svenpanne@chromium.org

Review URL: https://codereview.chromium.org/23530045

Patch from Marja Hölttä <marja@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16605 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Up until now we used PAGE_GUARD for guard pages in Windows, which
will raise a STATUS_GUARD_PAGE_VIOLATION exception on first access
and grant regular access afterwards. This behavior is required to
implement automatic stack checking, or more generally to implement
applications that monitor the growth of large dynamic data structures.

However, this is not what we want for our guard pages, which are
used as a security mechanism. What we really want is PAGE_NOACCESS
here, which is the Windows-equivalent of PROT_NONE that we use on
all other platforms.

R=cdn@chromium.org

Review URL: https://codereview.chromium.org/23458022

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16604 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=titzer@chromium.org

Review URL: https://codereview.chromium.org/23458036

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16601 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/21509003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16600 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Generate a custom OSR entrypoint for OSR compiles on all platforms, and transition to optimized code using the special entrypoint, instead of through the deoptimizer. Do not install the OSR compiled code as _the_ optimized code for a function.
Remove OSR-related stuff from deoptimizer.
BUG=
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/21340002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16599 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=verwaest@chromium.org
BUG=287476

Review URL: https://codereview.chromium.org/23480051

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16598 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23816009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16597 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Port r16587 (45fc067)

BUG=

Review URL: https://codereview.chromium.org/23444041
Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16596 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/23818005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16595 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=rossberg@chromium.org

Review URL: https://codereview.chromium.org/23684035

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16592 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=dslomov@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23676007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16591 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=dslomov@chromium.org
BUG=

Review URL: https://codereview.chromium.org/24023004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16590 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=titzer@chromium.org
TEST=mjsunit/compiler/escape-analysis

Review URL: https://codereview.chromium.org/23892007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16589 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

adds copying and autodispose as traits

R=marja@chromium.org, mstarzinger@chromium.org, svenpanne@chromium.org

BUG=

Review URL: https://codereview.chromium.org/23401003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16588 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=svenpanne@chromium.org
BUG=

Review URL: https://codereview.chromium.org/24027004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16587 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/24071002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16586 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23680014

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16585 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23561007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16584 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org
Signed-off-by: Thiago Farina <tfarina@chromium.org>

Review URL: https://codereview.chromium.org/23523034

Patch from Thiago Farina <tfarina@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16583 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/24037002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16582 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/23533015

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16581 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Port r16571 (9266312)

BUG=

Review URL: https://codereview.chromium.org/23780003
Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16580 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=chromium:285355
R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/24037003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16579 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/23542010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16578 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/24036002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16577 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TEST=test/mjsunit/lithium/MulI.js
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/23452022

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16576 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=bmeurer@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23537024

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16575 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

It should break out while loop once page_has_scan_on_scavenge_flag is found, there is no need check all of the items in the list.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/23597017

Patch from Bangfu Tao <bangfu.tao@samsung.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16574 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/23714007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16573 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org

Review URL: https://chromiumcodereview.appspot.com/23615012

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16572 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/23549019

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16571 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

R=dcarney@chromium.org

Review URL: https://codereview.chromium.org/23538007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16570 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/23522022

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16569 ce2b1a6d-e550-0410-aec6-3dcde31c8c00