CPU-eating DOS attacks against node.js servers. Based on code from
Bert Belder. This version only solves the issue for those that compile
V8 themselves or those that do not use snapshots. A snapshot-based
precompiled V8 will still have predictable string hash codes.
Review URL: http://codereview.chromium.org/9086006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10330 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Now with arm and x64 support. Additionally, added default unreachable case to switch statement in CompareIC::TargetState to make win and mac compilers happy.
Reviewer guide:
This is an exact copy of 10216 except:
src/arm/*
src/x64/*
src/ic.cc (added default case to swith in CompareIC::TargetState)
Review URL: http://codereview.chromium.org/8872060
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10219 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This includes specialcasing the generation when we know that the maps
of the two objects are the same. In addition, a new specialized
compare ic known objects cache is created.
The reason for the cache is that we need to have access to the stub
code from the roots; if we do not, the GC will collect the stub. In
this specialized case we use the map pointer as key in the cache, and
we always do a lookup before generating code. Actually hitting
something in the cache will happen very rarely, but we could
potentially overwrite an existing stub, which again will lead to the
GC collecting this old stub (even if it is referenced from other code
objects)
Review URL: http://codereview.chromium.org/8520006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10216 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL introduces a third mode next to the non-strict
(henceforth called 'classic mode') and 'strict mode'
which is called 'extended mode' as in the current
ES.next specification drafts. The extended mode is based on
the 'strict mode' and adds new functionality to it. This
means that most of the semantics of these two modes
coincide.
The 'extended mode' is entered instead of the 'strict mode'
during parsing when using the 'strict mode' directive
"use strict" and when the the harmony-scoping flag is
active. This should be changed once it is fully specified how the 'extended mode' is entered.
This change introduces a new 3 valued enum LanguageMode
(see globals.h) corresponding to the modes which is mostly
used by the frontend code. This includes the following
components:
* (Pre)Parser
* Compiler
* SharedFunctionInfo, Scope and ScopeInfo
* runtime functions: StoreContextSlot,
ResolvePossiblyDirectEval, InitializeVarGlobal,
DeclareGlobals
The old enum StrictModeFlag is still used in the backend
when the distinction between the 'strict mode' and the 'extended mode' does not matter. This includes:
* SetProperty runtime function, Delete builtin
* StoreIC and KeyedStoreIC
* StubCache
Review URL: http://codereview.chromium.org/8417035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10062 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Original commit message:
Add a level of indirection to exception handler addresses.
To support deoptimization of exception handlers, the handler address in the
stack is converted to a pair of code object and an index into a separate
table of code offsets. The index part is invariant under deoptimization.
The index is packed into the handler state field so that handler size does
not change.
R=vegorov@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8538011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9977 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To support deoptimization of exception handlers, the handler address in the
stack is converted to a pair of code object and an index into a separate
table of code offsets. The index part is invariant under deoptimization.
The index is packed into the handler state field so that handler size does
not change.
R=vegorov@chromium.org,fschneider@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8462010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9975 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Our Heap::FreeQueuedChunks generates fake inner chunks in large object
pages queued for freeing, so that StoreBuffer::Filter can recognize them
as pages to be freed. This also relies on MemoryChunk::Contains to work
properly, which is why the size field needs to be initialized as well.
R=vegorov@chromium.org
BUG=v8:1817
TEST=mozilla/js1_5/Regress/regress-360969-05
Review URL: http://codereview.chromium.org/8536009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9964 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Heap::Shrink is called from EnsureFromSpaceIsCommitted at the very start of the GC. At this moment live bytes counts on pages are in inconsistent states. Some pages might have been already swept but have not been yet reached by an incremental marker (or incremental marker is not in progress) and have live bytes count set to 0. Thus we can't rely only on LiveBytes to determine which pages can be released to the OS.
R=mstarzinger@chromium.org
BUG=100414
Review URL: http://codereview.chromium.org/8507038
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9953 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In some special (but probably very common) cases we can do better than loading
from a global cell for these global properties by emitting the corresponding
constant directly. This opens up opportunities for further improvements, coming
in a separate CL...
Review URL: http://codereview.chromium.org/7992002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9409 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The preprocessor defines ENABLE_LOGGING_AND_PROFILING and ENABLE_VMSTATE_TRACKING has been removed as these where required to be turned on for Crankshaft to work. To re-enable reducing the binary size by leaving out heap and CPU profiler a new set of defines needs to be created.
R=ager@chromium.org
BUG=v8:1271
TEST=all
Review URL: http://codereview.chromium.org//7350014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8622 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Due to issues relating mostly to chrome extensions we have lately been
running into OOMs that are caused by our executable space running
out. This change introduces flushing of code from regexps if we have
not used the code for 5 mark sweeps.
The approach is different from the normal function code flusing. Here
we make a copy of the code inside the data array, and exchange the
original code with a smi determined by the sweep_generation (a new
heap variable increased everytime we do mark sweep/compact). If we
encounter a smi in EnsureCompiled we simply reinstate the code
object. If, in the marking phase of mark sweep, we find a regexp that
already have a smi in the code field, and this is more than 5
generations old we flush the code from the saved index.
Review URL: http://codereview.chromium.org/7282026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8532 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Optimized frames are now handled by the debugger. When discovering optimized frames during stack inspection in the debugger they are "deoptimized" using the normal deoptimization code and the deoptimizer output information is used to provide frame information to the debugger.
Before this change the debugger reported each optimized frame as one frame no matter the number of inlined functuions that might have been called inside of it. Also all locals where reported as undefined. Locals can still be reposted as undefined when their value is not "known" by the optimized frame.
As the structures used to calculate the output frames when deoptimizing are not GC safe the information for the debugger is copied to another structure (DeoptimizedFrameInfo) which is registered with the global deoptimizer data and processed during GC.
R=fschneider@chromium.org
BUG=v8:1140
TEST=test/mjsunit/debug-evaluate-locals-optimized*
Review URL: http://codereview.chromium.org//7230045
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8464 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Before: every context cached the nearest enclosing function context. This
assumed that for nested contexts (i.e., with and catch contexts) the
enclosing function had a materialized link in the context chain.
Now: when necessary, we loop up the context chain to find such a context.
This enables catch contexts without forcing the enclosing function to
allocate its own context.
R=ager@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/7230047
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8452 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
are short of virtual memory. This should make V8 work in 64 bit
on OpenBSD in its default configuration. It is a simplified
version of the reverted 8133 which also lowered the non-code
heap size, causing test failures in Chromium on MacOS.
Review URL: http://codereview.chromium.org/7234004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8363 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Before, they had no extra slots and an extension object with one named
property. Now, they use the extension slot for the property name and have
an extra slot for the thrown object. This increases the size of the context
itself, but removes overall allocation and eliminates a level of indirection.
R=ager@chromium.org
Review URL: http://codereview.chromium.org/7152002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8277 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce separate maps for function and with contexts. Use the function
context map for testing whether a context is a function context (global
contexts are no longer function contexts).
Split the paths for allocating with and catch contexts.
Rename some functions. Generally refactor code to make it simpler.
R=ager@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/7003058
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8231 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
We used to have a linked list of nodes that were internally
block-allocated.
I kept the node blocks and put them on two lists: 1) the list of all
allocated blocks, 2) the list of blocks with used nodes. (1) is used
to reclaim blocks and (2) is used for traversal during GC. To make
traversal on scavenges faster the nodes holding new space objects are
grouped in an auxiliary array.
This changes the minimal memory usage from 5 words per global handle
to 4. Additional word is used for new space handles.
Review URL: http://codereview.chromium.org/7054072
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8186 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The current json parser and scanner inherits fromt he normal scanners and parsers,
which are more complicated than we need for parsing json.
The supplied scanner works directly on the string supplied and has a
fast case mode for scanning only ascii characters (it will simply
create a substring or a symbol directly from the existing string). To
allow for creating symbols from a substring I have added a
SubStringAsciiSymbolKey that creates the hash based from our string
without extracting the sub-string. In case we need to add the symbol
it simply creates the symbol directly from the characters inside the
given string.
Review URL: http://codereview.chromium.org/7039037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8029 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1) Add new type JSProxy for representing proxy objects.
Currently devoid of functionality, i.e., all properties are undefined.
2) Some rudimentary global $Proxy functions to create proxies.
Next step: Hook up getProperty and getOwnProperty handlers. Will probably
require introducing a new LookupResult type, which is a mixture of
INTERCEPTOR (handles any property) and CALLBACK (calls back to JS).
Can we unify this somehow?
TODO: Should probably rename existing Proxy type to something like
"Foreign", to avoid confusion.
Review URL: http://codereview.chromium.org/6932068
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7887 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The ScannerConstants class was originally static fields on the scanner class.
During creation of the stand-alone preparser and later isolates, it has been
moved into a separate class with a per-isolate instance.
It is used to hold caching unicode Predicate values.
This change renames the class to UnicodeCache, and passes a reference
to the instance down to methods that doesn't have an easy access to
an isolate (to avoid, e.g., having to do an Isolate::Current() for every
number parsed).
Review URL: http://codereview.chromium.org/6824071
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7584 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit adds current working versions of assembler, macro-assembler,
disassembler, and simulator.
All other mips arch files are replaced with stubbed-out versions that
will build.
Arch independent files are updated as needed to support building and
running mips.
The only test is cctest/test-assembler-mips, and this passes on the
simulator and on mips hardware.
TEST=none
BUG=none
Patch by Paul Lind from MIPS.
Review URL: http://codereview.chromium.org/6730029/
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7388 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Worth mentioning:
- Specialized versions of pixel array and store/loads inside the generic stubs have been removed, since to have parity for all external arrays, 8 different versions would have to be inlined/checked.
- There's a new constant in v8.h for external arrays with pixel array elements.
Review URL: http://codereview.chromium.org/6546036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7106 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Non-moveable code-stube are allocated in large object space. They are only required on ARM where the different C-entry stubs are required to never move.
This gets rid of pre-computing these stubs and hope that they never move. Also for crankshaft the C-entry stub which saved doubles is not generated in the snapshot so it ends up being generated at runtime and potentially move.
Review URL: http://codereview.chromium.org/6626072
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The main issue was due to multiple recompilations of functions. Now
code objects are grouped by function using SFI object address.
JSFunction objects are no longer tracked, instead we track SFI object
moves. To pick a correct code version, we now sample return addresses
instead of JSFunction addresses.
tools/{linux|mac|windows}-tickprocessor scripts differentiate
between code optimization states for the same function
(using * and ~ prefixes introduced earlier).
DevTools CPU profiler treats all variants of function code as
a single function.
ll_prof treats each optimized variant as a separate entry, because
it can disassemble each one of them.
tickprocessor.py not updated -- it is deprecated and will be removed.
BUG=v8/1087,b/3178160
TEST=all existing tests pass, including Chromium layout tests
Review URL: http://codereview.chromium.org/6551011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6902 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
idle notifications after the one that causes the mark-compact
collection unless four or more garbage collections (scavenges) have
occurred.
The embedder should stop sending idle notifications once V8 returns
true from the IdleNotification call. This change is being defensive so
it will not hurt as badly if embedders continue to send idle
notifications.
Review URL: http://codereview.chromium.org/5726005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5981 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Allow build-time customization of the max semispace size. Building a
version of V8 with snapshots and with a non-default max semi-space
size is much easier when you can set the max semispace size in the
build environment.
Review URL: http://codereview.chromium.org/4937001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5823 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently weak handles retain an object for another GC round (oftem times,
major GC round.) Instrumenting Chromium shows that navigation leaves
many global objects which are only collected in next go. Let's
attempt to collect more garbage when approacing OOM condition.
This is a better version of rolled out r5455: now it's correctly
rebuilds object groups between additional GCs.
Review URL: http://codereview.chromium.org/4295004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5761 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
An attempt to retrieve security context for a function may fail if the
destination heap space is in an incomplete state. To fix this, we only
record unknown functions discovered at GC object moves, and then
register them after GC completes.
BUG=crbug/59627
Review URL: http://codereview.chromium.org/3763012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5667 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Since 2.6.31 perf_events interface has been available in the
kernel. There's a nice tool called "perf" (linux-2.6/tools/perf) that
uses this interface and provides capabilities similar to oprofile. The
simplest form of its usage is just dumping the raw log (trace) of
events generated by the kernel. In this patch I'm adding a script
(tools/ll_prof.py) to build profiles based on perf trace and our code
log. All the heavy-lifting is done by perf. Compared to oprofile agent
this approach does not require recompilation and supports code moving
garbage collections.
Expected usage is documented in the ll_prof's help. Basically one
should run V8 under perf passing --ll-prof flag and then the produced
logs can be analyzed by tools/ll_prof.py.
The new --ll-prof flag enables logging of generated code object
locations and names (like --log-code), and also of their bodies, which
can be later disassembled and annotated by the script.
Review URL: http://codereview.chromium.org/3831002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5663 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The object's space in Page starts after Page header and is aligned to kMapAlignment which is 32 bytes on 32-bit and 8 bytes on 64-bit.
In case of 64-bit target, the current page header size is exactly 32 bytes so we get the code magically aligned at 32 bytes but it is better to have a separate CODE_POINTER_ALIGN macro to make sure the object space in Page is aligned properly for both maps and code.
There could be a small waste of bytes sometimes (since both Page header and Code header sizes are aligned separately) but it seems the optimal one would involve cross-dependencies between .h files and not clear if it's worth it.
This is a back-port from Isolates branch.
Review URL: http://codereview.chromium.org/3461021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5526 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The cause for missing functions is that some of them are created
from compiled code (see FastNewClosureStub), and thus not get
registered in profiler's code map.
My solution is to hook on GC visitor to provide JS functions
addresses to profiler, only if it is enabled.
BUG=858
TEST=
Review URL: http://codereview.chromium.org/3417019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5523 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The number of inobject properties used to be derived from the number
of this property assignments in the constructor (and increased by 2 to
allow for properties added later). This very often leads to wasted inobject
slots.
This patch reclaims some of the unused inobject space by the following method:
- for each constructor function the first several objects are allocated using the initial
("generous) instance size estimation (this is called 'tracking phase').
- during the tracking phase map transitions are tracked and actual property counts are collected.
- at the end of the tracking phase instance sizes in the maps are decreased if necessary
(starting with the function's initial map and traversing the transition tree).
- all further allocation use more realistic instance size estimation.
Shrinking generously allocated objects without costly heap traversal is made possible
by initializing their inobject properties with one_pointer_filler_map (instead of undefined).
The initial slack for the generous allocation is increased from 2 to 6 which really helps some tests.
Review URL: http://codereview.chromium.org/3329019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5510 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently weak handles retain an object for another GC round (oftem times,
major GC round.) Instrumenting Chromium shows that navigation leaves
many global objects which are only collected in next go. Let's
attempt to collect more garbage when approacing OOM condition.
Review URL: http://codereview.chromium.org/3327021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5455 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
That could improve chances for commit success as currently,
if we moved free pages out of order, we cannot shrink spaces.
However, when we experience problems commiting from space back, we should
use most of resources at our disposal.
Also get rid of currently unused parameter to DeallocateFunction.
Review URL: http://codereview.chromium.org/3260001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5372 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the code object's instructions.
This allows us to find a code object using just the pc. This approach
uses a cache (PcToCodeCache) to make sure we don't continuously have
to iterate heap pages.
This change eliminates the need for cooking and uncooking of stack frames.
Review URL: http://codereview.chromium.org/3226014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5369 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
r5147 wrongly assumed that a code cache for a slow case map is always empty.
This patch solves this: whenever we attempt to add a stub to a map's code cache
we check that this map is cached. If it is we give the object its own copy
of the map and only then modify the map.
Review URL: http://codereview.chromium.org/3134027
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5342 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Object model changes
----------------------------------------
New fixed_cow_array_map is used for the elements array of a JSObject
to mark it as COW. The JSObject's map and other fields are not
affected. The JSObject's map still has the "fast elements" bit set. It
means we can do only the receiver map check in keyed loads and the
receiver and the elements map checks in keyed stores. So introducing
COW arrays doesn't hurt performance of these operations. But note that
the elements map check is necessary in all mutating operations because
the "has fast elements" bit now means "has fast elements for reading".
EnsureWritableFastElements can be used in runtime functions to perform
the necessary lazy copying.
Generated code changes
----------------------------------------
Generic keyed load is updated to only do the receiver map check (this
could have been done earlier). FastCloneShallowArrayStub now has two
modes: clone elements and use COW elements. AssertFastElements macro
is added to check the elements when necessary. The custom call IC
generators for Array.prototype.{push,pop} are updated to avoid going
to the slow case (and patching the IC) when calling the builtin should
work.
COW enablement
----------------------------------------
Currently we only put shallow and simple literal arrays in the COW
mode. This is done by the parser.
Review URL: http://codereview.chromium.org/3144002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5275 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
That could allow us to understand why commit of from space sometimes fails.
Another option would be start a separate structure with OS-related info, but
as it's a single field, let's put it into HeapStats, at least for now.
Review URL: http://codereview.chromium.org/3118013
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5261 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in allowing more flexible compilation and to simplify builtins lookup.
This changes a number of places where code objects are assigned to
SharedFunctionInfo objects to also assign this code object to the
JSFunction. In addition, the code flushing is changed slightly to
accomodate this (we need to flush the code from functions pointing to
SharedFunctionInfo objects that has already been flushed).
Review URL: http://codereview.chromium.org/3120006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5233 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To trace objects between snapshots, an external map of object tags is
maintained. After the first heap snapshot has been taken, the map is
updated by reporting object moves from the GC. If no snapshots were
taken, there is no overhead (except for flag checking).
I considered graph comparison algorithms that doesn't require using
object tags, but they are all of a high computational complexity, and
will still fail to detect object moves properly, even for trivial
cases, so using tags looks like unavoidable.
Review URL: http://codereview.chromium.org/3020002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5078 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The static ScopeInfo members moved into this class.
The new class is named ScopeInfoObject which I am not proud of,
better ideas are very welcome.
Also got rid of the sentinels in the serialized scope info which saves 3 words per function
and is not slower.
Review URL: http://codereview.chromium.org/2908009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5067 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Use virtually dispatched specialized scavengers instead of single generic ScavengeObjectSlow implementation.
Rollback of r5041 with assertion checking callback alignment removed. Map space is iterated in a special fashion during scavenges so special callback alignment is not required.
Review URL: http://codereview.chromium.org/2950003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5047 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
A potential issue with this change is creating lots of maps when
objects flip between fast/slow elements modes. We could add special
transitions to avoid this. Yet testing this on our benchmarks, gmail,
and wave seems to indicate that this is not a real problem.
Review URL: http://codereview.chromium.org/2870018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4941 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Stable high survival rates of young objects both during partial and
full collection indicate that mutator is either building or modifying
a structure with a long lifetime.
In this case we aggressively raise old generation memory limits to
postpone subsequent mark-sweep collection and trade memory space
for the mutation speed.
Review URL: http://codereview.chromium.org/2809032
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4938 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If a two-byte string only contains ascii characters, then we can save
memory when flattening a cons string containing it. Similarly we can
use this in Array.prototype.join implementation. To track this a new
bit is added to instance type. This bit is used as a hint in generated
code and in runtime functions.
To enable testing a new V8 extension is added controlled by
--expose-externalize-string flag.
Review URL: http://codereview.chromium.org/2762008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4894 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Changed the disposal of external string resources to call a virtual Dispose method on the resource. The default inplementation of Dispose deletes the object and will capture the delete operator matching the new operator used to allocate the object.
Review URL: http://codereview.chromium.org/2658008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4816 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This adds an additional step to full gc, removing code from functions
that are no longer in the compilation cache. The code is replaced with
a lazy compile version enabling us to recompile the function in case
we do actually need it again.
Review URL: http://codereview.chromium.org/2632003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4814 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- New сardmarking write barrier handles large objects and normal objects in a similar fashion (no more additional space for pointer tracking is required, no conditional branches in WB code).
- Changes to enable oldspaces iteration without maps decoding:
-- layout change for FixedArrays: length is stored as a smis (initial patch by
Kevin Millikin)
-- layout change for SharedFunctionInfo: integer fields are stored as smi on
arm, ia32 and rearranged on x64.
-- layout change for String: meaning of LSB bit is fliped (1 now means hash not
computed); on x64 padding is added.
-- layout of maps is _not_ changed. Map space is currently iterated in a special
way.
Review URL: http://codereview.chromium.org/2144006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4715 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
-- layout change for FixedArrays: length is stored as a smis (initial patch by Kevin Millikin)
-- layout change for SharedFunctionInfo: integer fields are stored as smi on arm, ia32 and rearranged on x64.
-- layout change for String: meaning of LSB bit is fliped (1 now means hash not computed); on x64 padding is added.
-- layout of maps is _not_ changed. Map space is currently iterated in a special way.
- Cardmarking write barrier. New barrier handles large objects and normal objects in a similar fashion (no more additional space for pointer tracking is required, no conditional branches in WB code).
Review URL: http://codereview.chromium.org/2101002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4685 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Faster hashing for sequential strings.
* When adding short external two-byte strings try to convert them
back to ascii. Chances are high the embedder uses two-byte
representation even for ascii strings. This optimization saves
memory and makes hashing faster.
Review URL: http://codereview.chromium.org/1444001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4300 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
registration of external references in Proxy objects).
I moved the declaration of the two functions to stub-cache.h
because with all the types they use it's hard to declare them
anywhere else. But the actual definition is still in runtime.cc
near to the place where they are used.
Review URL: http://codereview.chromium.org/1079012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4231 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
