The patch introduces CommittedPhysicalMemory function to
the Heap class that reports committed *physical* memory acquired
for the heap from the OS.
It is important because some OSes may defer actual committment on e.g.
first access to the region.
So reporting just plain committed size led to various weird artifacts
like showing V8 allocated memory higher than the whole process
private size.
BUG=v8:2191
Review URL: https://codereview.chromium.org/11066118
Patch from Alexei Filippov <alph@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12793 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The patch introduces CommittedPhysicalMemory function to the Heap class
that reports committed *physical* memory acquired from the OS.
It is important because some OSes may postpone actual commitment on e.g.
first access to the previously committed region.
So reporting just plain committed size led to various weird artifacts
like DevTools showing V8 allocated memory higher than the whole process
private size.
BUG=v8:2191
Review URL: https://codereview.chromium.org/10961042
Patch from Alexei Filippov <alph@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12625 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the speed of deserializing code. The current startup
time improvement for V8 is around 6%, but code deserialization
is speeded up disproportionately, and we will soon have more
code in the snapshot.
* Removed support for deserializing into large object space.
The regular pages are 1Mbyte now and that is plenty. This
is a big simplification.
* Instead of reserving space for the snapshot we actually
allocate it now. This removes some special casing from
the memory management and simplifies deserialization since
we are just bumping a pointer rather than calling the
normal allocation routines during deserialization.
* Record in the snapshot how much we need to boot up and
allocate it instead of just assuming that allocations in
a new VM will always be linear.
* In the snapshot we always address an object as a negative
offset from the current allocation point. We used to
sometimes address from the start of the deserialized data,
but this is less useful now that we have good support for
roots and repetitions in the deserialization data.
* Code objects were previously deserialized (like other
objects) by alternating raw data (deserialized with memcpy)
and pointers (to external references, other objects, etc.).
Now we deserialize code objects with a single memcpy,
followed by a series of skips and pointers that partially
overwrite the code we memcopied out of the snapshot.
The skips are sometimes merged into the following
instruction in the deserialization data to reduce dispatch
time.
* Integers in the snapshot were stored in a variable length
format that gives a compact representation for small positive
integers. This is still the case, but the new encoding can
be decoded without branches or conditional instructions,
which is faster on a modern CPU.
Review URL: https://chromiumcodereview.appspot.com/10918067
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12505 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL adds multiple things:
Transition arrays do not directly point at their descriptor array anymore, but rather do so via an indirect pointer (a JSGlobalPropertyCell).
An ownership bit is added to maps indicating whether it owns its own descriptor array or not.
Maps owning a descriptor array can pass on ownership if a transition from that map is generated; but only if the descriptor array stays exactly the same; or if a descriptor is added.
Maps that don't have ownership get ownership back if their direct child to which ownership was passed is cleared in ClearNonLiveTransitions.
To detect which descriptors in an array are valid, each map knows its own NumberOfOwnDescriptors. Since the descriptors are sorted in order of addition, if we search and find a descriptor with index bigger than this number, it is not valid for the given map.
We currently still build up an enumeration cache (although this may disappear). The enumeration cache is always built for the entire descriptor array, even if not all descriptors are owned by the map. Once a descriptor array has an enumeration cache for a given map; this invariant will always be true, even if the descriptor array was extended. The extended array will inherit the enumeration cache from the smaller descriptor array. If a map with more descriptors needs an enumeration cache, it's EnumLength will still be set to invalid, so it will have to recompute the enumeration cache. This new cache will also be valid for smaller maps since they have their own enumlength; and use this to loop over the cache. If the EnumLength is still invalid, but there is already a cache present that is big enough; we just initialize the EnumLength field for the map.
When we apply ClearNonLiveTransitions and descriptor ownership is passed back to a parent map, the descriptor array is trimmed in-place and resorted. At the same time, the enumeration cache is trimmed in-place.
Only transition arrays contain descriptor arrays. If we transition to a map and pass ownership of the descriptor array along, the child map will not store the descriptor array it owns. Rather its parent will keep the pointer. So for every leaf-map, we find the descriptor array by following the back pointer, reading out the transition array, and fetching the descriptor array from the JSGlobalPropertyCell. If a map has a transition array, we fetch it from there. If a map has undefined as its back-pointer and has no transition array; it is considered to have an empty descriptor array.
When we modify properties, we cannot share the descriptor array. To accommodate this, the child map will get its own transition array; even if there are not necessarily any transitions leaving from the child map. This is necessary since it's the only way to store its own descriptor array.
Review URL: https://chromiumcodereview.appspot.com/10909007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12492 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Highlights of this CL:
* Introduced a new opcode in the deoptimizer for a setter stub frame.
* Added a global setter stub for returning after deoptimizing a setter.
* We do not need special deopt support for getters, although the getter stub creates an internal frame. The normal machinery works just right for this case, although we generate a stack that can never occur during normal fullcode execution. If this hurts us one day, we can parameterize and reuse the setter deopt machinery.
Review URL: https://chromiumcodereview.appspot.com/10855098
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12328 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in anticipation of the upcoming lexical global scope.
Mostly automatised as:
for FILE in `egrep -ril "global[ _]?context" src test/cctest`
do
echo $FILE
sed "s/Global context/Native context/g" <$FILE >$FILE.0
sed "s/global context/native context/g" <$FILE.0 >$FILE.1
sed "s/global_context/native_context/g" <$FILE.1 >$FILE.2
sed "s/GLOBAL_CONTEXT/NATIVE_CONTEXT/g" <$FILE.2 >$FILE.3
sed "s/GlobalContext/NativeContext/g" <$FILE.3 >$FILE
rm $FILE.[0-9]
done
R=mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/10832342
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12325 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
AccessorPair related transitions are now also stored as single map links, simplifying the code that handles transitions. AccessorPairs can now be shared between descriptor arrays, since they can only be mutated after another transition anyway; during which the pair is copied before writing.
Review URL: https://chromiumcodereview.appspot.com/10784014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Specifically:
- In parser, check that all exports are defined.
- Move JSModule allocation from parser to scope resolution.
- Move JSModule linking from full codegen to scope resolution.
- Implement module accessors for exported value members.
- Allocate module contexts statically along with JSModules
(to allow static linking), but chain them when module literal is evaluated.
- Make module contexts' extension slot refer to resp. JSModule
(makes modules' ScopeInfo accessible from context).
- Some other tweaks to context handling in general.
- Make any code containing module literals (and thus embedding
static references to JSModules) non-cacheable.
This enables accessing module instance objects as expected.
Import declarations are a separate feature and do not work yet.
R=mstarzinger@chromium.org
BUG=v8:1569
TEST=
Review URL: https://chromiumcodereview.appspot.com/10690043
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12010 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Constructs the (generally cyclic) graph of module instance objects
and populates their exports. Any exports other than nested modules
are currently set to 'undefined' (but already present as properties).
Details:
- Added new type JSModule for instance objects: a JSObject carrying a context.
- Statically allocate instance objects for all module literals (in parser 8-}).
- Extend interfaces to record and unify concrete instance objects,
and to support iteration over members.
- Introduce new runtime function for pushing module contexts.
- Generate code for allocating, initializing, and setting module contexts,
and for populating instance objects from module literals.
Currently, all non-module exports are still initialized with 'undefined'.
- Module aliases are resolved statically, so no special code is required.
- Make sure that code containing module constructs is never optimized
(macrofy AST node construction flag setting while we're at it).
- Add test case checking linkage.
Baseline: http://codereview.chromium.org/9722043/R=svenpanne@chromium.org,mstarzinger@chromium.org
BUG=
TEST=
Review URL: https://chromiumcodereview.appspot.com/9844002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11336 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
