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This feature is currently only enabled when DDMS's allocation tracking
is enabled. In the future there should be a way to enable this feature
before an application starts.

Also updates DDMS's recent allocation tracking to use a new backend
data structure that is shared with this feature.

The following system properties controls customizable parameters:
dalvik.vm.allocTrackerMax: max number of objects that have allocation
                           records, default 512K;

dalvik.vm.recentAllocMax:  max number of records that are sent to DDMS
                           when clicking "Get allocation" button,
                           default 64K-1 (limit of the protocol);

dalvik.vm.allocStackDepth: max number of stack frames in an allocation
                           record, default 4.

Bug: 20037135
Change-Id: I26ed378a5613678bd3c43e846025f90470a8e059

Optimizing + quick tests are passing, devices boot.

TODO: Test and fix bugs in mips64.

Saves 16 bytes per most ArtMethod, 7.5MB reduction in system PSS.
Some of the savings are from removal of virtual methods and direct
methods object arrays.

Bug: 19264997
Change-Id: I622469a0cfa0e7082a2119f3d6a9491eb61e3f3d

Avoid undefined behavior for arm64 stemming from 1u << 32 in
loops with upper bound kNumberOfXRegisters.

Create iterators for enumerating bits in an integer either
from high to low or from low to high and use them for
<arch>Context::FillCalleeSaves() on all architectures.

Refactor runtime/utils.{h,cc} by moving all bit-fiddling
functions to runtime/base/bit_utils.{h,cc} (together with
the new bit iterators) and all time-related functions to
runtime/base/time_utils.{h,cc}. Improve test coverage and
fix some corner cases for the bit-fiddling functions.

Bug: 13925192
Change-Id: I704884dab15b41ecf7a1c47d397ab1c3fc7ee0f7

May help prevent bugs maybe.

Change-Id: Ie73d469dfcd078492ecb3aa28682b42707221202

Bug: 20554807
Change-Id: I1cd855507c3f4e191035dbc2c429e1b8b344d81b

Also fixed some lines that were too long, and a few other minor
details.

Change-Id: I6efba5fb6e03eb5d0a300fddb2a75bf8e2f175cb

Speedup on N4:
MemAllocTest 3044 -> 2396 (~21% reduction)
BinaryTrees  4101 -> 2929 (~26% reduction)

Bug: 9986565
Change-Id: Ia1d1a37b9e001f903c3c056e8ec68fc8c623a78b

Bug: 12687968
Change-Id: I62f70274d47df6d6cab714df95c518b750ce3105

If a large object allocation fails, we now try the normal allocators.

Bug: 18124612

(cherry picked from commit f1c4d0e3)

Change-Id: Ib83ebe53fbdd83aa2d23fd10a8bb10e149f8918f

If a large object allocation fails, we now try the normal allocators.

Bug: 18504942
Change-Id: I18b9759d6af885556941542c57fec584f18197f1

Remove extra semicolons.

Dollar signs in C++ identifiers are an extension.

Named variadic macros are an extension.

Binary literals are a C++14 feature.

Enum re-declarations are not allowed.

Overflow.

Change-Id: I7d16b2217b2ef2959ca69de84eaecc754517714a

Avoids recomputation in the hot allocation path when instrumentation is
enabled.

Change-Id: Ic6e7d7d0744f4756787f75d21fddd3c50280b588

Possible previous bug:
Allocation fails due to OOM and the collector transitions.
This caused us to incorrectly retry the allocation with a pending
exception. We now return null if there is a pending exception.

Bug: 17164348

(cherry picked from commit 27f5ae83)

Change-Id: I8e7ecafbade7f0b955812df3dd7c94fdc696c856

Possible previous bug:
Allocation fails due to OOM and the collector transitions.
This caused us to incorrectly retry the allocation with a pending
exception. We now return null if there is a pending exception.

Bug: 17164348
Change-Id: I22eab472afb2fdea6e800963ccb35ec0755ba0e6

There was a problem where we would call SetStatus when we had an OOM
error. This results in attempting to find the ExceptionInInitializer
class which if not loaded does more allocations resulting in an
infinite loop.

Also some cleanup addressing other comments.

Bug: 16082350

(cherry picked from commit fd22d5ba)

Change-Id: Ie291eb0f52ba9c63f24591fae691dd9f393e6ccb

There was a problem where we would call SetStatus when we had an OOM
error. This results in attempting to find the ExceptionInInitializer
class which if not loaded does more allocations resulting in an
infinite loop.

Also some cleanup addressing other comments.

Bug: 16082350
Change-Id: I5c1e638a03ddf700ab4e9cad9a3077d2b1b26c43

New TLAB allocator doesn't increment bytes allocated until we allocate
a new TLAB. This increases allocation performance by avoiding a CAS.

MemAllocTest:
Before GSS TLAB: 3400ms.
After GSS TLAB: 2750ms.

Bug: 9986565

Change-Id: I1673c27555330ee90d353b98498fa0e67bd57fad

Merge ART from AOSP to lmp-preview-dev.

Change-Id: I0f578733a4b8756fd780d4a052ad69b746f687a9

This fixes an issue with heap verification which was caused when
the allocation stack overflowed. This resulted in heap verification
failures since we were storing the newly allocated object in a
handle scope without having it be live either in the live bitmap
or allocation stack. We now push the object in the reserve area
before we do a GC due to allocation stack overflow.

Change-Id: I83b42c4b3250d7eaab1b49e53066e21c8656a740

Change-Id: I4858d9cbed95e5ca560956b9dabd976cebe68333

Delete SirtRef and replaced it with Handle. Handles are value types
which wrap around StackReference*.

Renamed StackIndirectReferenceTable to HandleScope.

Added a scoped handle wrapper which wraps around an Object** and
restores it in its destructor.

Renamed Handle::get -> Get.

Bug: 8473721

Change-Id: Idbfebd4f35af629f0f43931b7c5184b334822c7a

Pass in a pre-fence barrier object that sets in the array length
instead of setting it after returning from AllocObject().

Fix another potential bug due to the wrong default pre-fence barrier
parameter value. Since this appears error-prone, removed the default
parameter value and make it an explicit parameter.

Fix another potential moving GC bug due to a lack of a SirtRef.

Bug: 13097759
Change-Id: I466aa0e50f9e1a5dbf20be5a195edee619c7514e

Add an option for Baker in addition to Brooks.

Bug: 12687968
Change-Id: I8a31db817ff6686c72951b6534f588228e270b11

Bug: 12687968

Change-Id: Ifc9ee86249f7938f51495ea1498cf0f7853a27e8

Scan only dirty cards, as opposed to the whole space, to find
references from the non-moving spaces to the bump pointer spaces at
bump pointer space only collections.

With this change, the Ritz MemAllocTest speeds up by 8-10% on host and
2-3% on N4. The Ritz EvaluateFibonacci speeds up by 8% and its average
pause time is reduced by 43% on N4.

Bug: 11650816
Change-Id: I1eefe75776bc37e24673b301ffa65a25f9bd4cde

This change fixes the following problem with the GSS collector: if the
post zygote non-moving space happens to be located after the bump
pointer spaces, the bump pointer space is treated wrongfully as an
immune space. The reasons are 1) the immune space is represented by a
simple address range and 2) the GSS collector treats the post zygote
non-moving space as an immune space at a bump pointer space only
collection.

In addition, this change makes it a reality that all the non-moving
spaces are adjacent, which we tend to assume in the code (eg. the
notion of the immune space represented by a simple address range.)
This should help avoid potential confusions in the future.

Fix a DCHECK failure where usable_size isn't set properly when
-XX:UseTLAB is used.

Change-Id: I585920e433744a390f87e9a25bef6114b2a4623f

Added verify object calls to SirtRef, IndirectReferenceTable,
ReferenceTable.

Removed un-needed verify object in ScopedObjectAccess / DecodeJObject
since object sources are handled.

Bug: 12934910
Change-Id: I55a46a8ea61fed2a77526eda27fd2cce97a9b125

RequestConcurrentGC can cause thread suspension, this means that
another thread could transition the heap or cause moving GC.

Bug: 12934910

Change-Id: I5c07161e2e849d7acbdf939f1c24e1ba361a1d6a

Added a dynamic large_object_threshold_ variable which is max int
when the large object space is disabled.

No longer clear timing logger timings after zygote creation since
it is not required and removes the boot semispace timings.

Change-Id: I693865f4699cc32381199377239854c6ec42f37e

Address other outstanding review comments.

Change-Id: Iaffe04de080772a0d0c5fd973bcac0e23c8c3e25

Work-in-progress to allow arrays to fill usable size. Bug: 13028925.
Use C++11's override keyword on GCC >= 2.7 to ensure that we override GC and
allocator methods.
Move initial mirror::Class set up into a Functor so that all allocated objects
have non-zero sizes. Use this property to assert that all objects are never
larger than their usable size.
Other bits of GC related clean-up, missing initialization, missing use of
const, hot methods in .cc files, "unimplemented" functions that fail at
runtime in header files, reducing header file includes, move valgrind's space
into its own files, reduce number of array allocation routines.

Change-Id: Id5760041a2d7f94dcaf17ec760f6095ec75dadaa

This feature is disabled by default.

Verified that the Brooks pointers are installed correctly by using the
CMS/SS collectors.

Change-Id: Ia9be9814ab6e29169ac85edc4792ce8c81d552a9

VerifyObject no longer resides in heap. You can now enable
VerifyObject for non-debug builds. VerifyStack is still slow, so it
is now guarded by its own flag.

Fixed the image writer to not use verification at places where
verification fails due to invalid reads.

Fixed RosAlloc to use SizeOf which doesn't call verify object.

Added a flag paremeter to some of the mirror getters / setters to
be able to selectively disable VerifyObject on certain calls.

Optimized the GC to not verify each object multiple times during
object scanning if verify object is enabled.

Added 3 verification options: verify reads, verify this, and verify
writes so that you can select how much verification you want for
mirror getters and setters.

Removed some useless DCHECKs which would slow debug builds without
providing any benefits.

TODO: RosAlloc verification doesn't currently work with verify
objects.

Bug: 12934910
Bug: 12879358

Change-Id: Ic61033104dfc334543f89b0fc0ad8cd4f4015d69

With this change, Ritz MemAllocTest gets ~14% faster on N4.

Bug: 9986565
Change-Id: I2fb7d6f7c5daa63dd4fc73ba739e6ae4ed820617

When the process state changes to a state which does not perceives
jank, we copy from the main free-list backed allocation space to
the bump pointer space and enable the semispace allocator.

When we transition back to foreground, we copy back to a free-list
backed space.

Create a seperate non-moving space which only holds non-movable
objects. This enables us to quickly wipe the current alloc space
(DlMalloc / RosAlloc) when we transition to background.

Added multiple alloc space support to the sticky mark sweep GC.

Added a -XX:BackgroundGC option which lets you specify
which GC to use for background apps. Passing in
-XX:BackgroundGC=SS makes the heap compact the heap for apps which
do not perceive jank.

Results:
Simple background foreground test:
0. Reboot phone, unlock.
1. Open browser, click on home.
2. Open calculator, click on home.
3. Open calendar, click on home.
4. Open camera, click on home.
5. Open clock, click on home.
6. adb shell dumpsys meminfo

PSS Normal ART:
Sample 1:
    88468 kB: Dalvik
     3188 kB: Dalvik Other
Sample 2:
    81125 kB: Dalvik
     3080 kB: Dalvik Other

PSS Dalvik:
Total PSS by category:
Sample 1:
    81033 kB: Dalvik
    27787 kB: Dalvik Other
Sample 2:
    81901 kB: Dalvik
    28869 kB: Dalvik Other

PSS ART + Background Compaction:
Sample 1:
    71014 kB: Dalvik
     1412 kB: Dalvik Other
Sample 2:
    73859 kB: Dalvik
     1400 kB: Dalvik Other

Dalvik other reduction can be explained by less deep allocation
stacks / less live bitmaps / less dirty cards.

TODO improvements: Recycle mem-maps which are unused in the current
state. Not hardcode 64 MB capacity of non movable space (avoid
returning linear alloc nightmares). Figure out ways to deal with low
virtual address memory problems.

Bug: 8981901

Change-Id: Ib235d03f45548ffc08a06b8ae57bf5bada49d6f3

Change-Id: I937ea93e6df1835ecfe2d4bb7d84c24fe7fc097b

Added a thread local allocator to the heap, each thread has three
pointers which specify the thread local buffer: start, cur, and
end. When the remaining space in the thread local buffer isn't large
enough for the allocation, the allocator allocates a new thread
local buffer using the bump pointer allocator.

The bump pointer space had to be modified to accomodate thread
local buffers. These buffers are called "blocks", where a block
is a buffer which contains a set of adjacent objects. Blocks
aren't necessarily full and may have wasted memory towards the
end. Blocks have an 8 byte header which specifies their size and is
required for traversing bump pointer spaces.

Memory usage is in between full bump pointer and ROSAlloc since
madvised memory limits wasted ram to an average of 1/2 page per
block.

Added a runtime option -XX:UseTLAB which specifies whether or
not to use the thread local allocator. Its a NOP if the garbage
collector is not the semispace collector.

TODO: Smarter block accounting to prevent us reading objects until
we either hit the end of the block or GetClass() == null which
signifies that the block isn't 100% full. This would provide a
slight speedup to BumpPointerSpace::Walk.

Timings: -XX:HeapMinFree=4m -XX:HeapMaxFree=8m -Xmx48m
ritzperf memalloc:
Dalvik -Xgc:concurrent: 11678
Dalvik -Xgc:noconcurrent: 6697
-Xgc:MS: 5978
-Xgc:SS: 4271
-Xgc:CMS: 4150
-Xgc:SS -XX:UseTLAB: 3255

Bug: 9986565
Bug: 12042213

Change-Id: Ib7e1d4b199a8199f3b1de94b0a7b6e1730689cad

Slight reduction in Zygote size, memory savings are in the noise.
Before: Zygote size: 8739224
After: Zygote size: 8733568

Fixed a bug where we didn't set the concurrent start bytes after
switching the allocator from bump pointer to ROSAlloc in the
zygote. This caused excessive memory usage.

Added the method verifiers as roots to fix an issue caused by
RegTypes holding a Class*.

Added logic to clear card table in the SemiSpace collector, this
reduces DalvikOther from ~2400k -> ~1760k when using the SemiSpace
collector.

Added a missing lock to the timing loggers which caused a rare
one time crash in std::set.

Bug: 11771255
Bug: 8499494
Bug: 10802951

Change-Id: I99d2b528cd51c1c5ed7012e3220b3aefded680ae

Memory usage regressed since we didn't properly update
concurrent_start_bytes_ when changing collectors.

Bug: 12034247

Change-Id: I1c69e71cd2919e0d3bf75485a4ac0b0aeca59278

This had been failing with the error message:

object_test F  2360  2360 art/runtime/gc/heap-inl.h:139] Check failed: !running_on_valgrind_

Then, this failing DCHECK was removed in a refactoring in
cbb2d20b, I believe.

This change adds back a DCHECK that's equivalent to the old one and
fixes ObjectTest.CheckAndAllocArrayFromCode by replacing a
CheckAndAllocArrayFromCode call with a
CheckAndAllocArrayFromCodeInstrumented call.

Bug: 11670287
Change-Id: Ica2f707b9a9ff48ef973b9e326a4d9786c1781f8