Code addresses are now written as an offset from the previous address for ticks, code move and delete events. Employed backreference and RLE compression for code move and delete events. This gives additional 30% log size reduction for benchmarks run w/o snapshot.
Overall compression results (compared with the revision of V8 having no compression):
- V8: 70% size reduction for benchmarks run w/o snapshot (for reference, gzip gives 87%)
- Chromium: 65% size reduction for public html version of benchmarks (v4) (for reference, gzip gives 90%)
The one obvious opportunity for improving compression results in Chromium is to compress URLs of scripts.
Review URL: http://codereview.chromium.org/125114
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2162 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Marsaglia's multiply-with-carry instead of mixing the
bits obtained from calling the system random() twice.
This seems to be a bit faster and gives a better
distribution than the system random() in particular on
Windows.
Review URL: http://codereview.chromium.org/126113
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2159 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
For each frame it is now possible to request information on the scope chain. Each scope in the chain can have one of the types local, global, with and closure. For scopes of type global and with the mirror for the actual global or with object is available. For scopes of type local and closure a plain JavaScript object with the materialized content of the scope is created and its mirror is returned. Depending on the level of possible optimization the content of the materialized local and closure scopes might only contain the names which are actually used.
To iterate the scope chain an iterator ScopeIterator have been added which can provide the type of each scope for each part of the chain. This iterator creates an artificial local scope whenever that is present as the context chain does not include the local scope.
To avoid caching the mirror objects for the materialized the local and closure scopes transient mirrors have been added. They have negative handles and cannot be retrieved by subsequent lookup calls. Their content is part of a single response.
For debugging purposes an additional runtime function DebugPrintScopes is been added.
Added commands 'scopes' and 'scope' to the developer shell and fixed the dir command.
BUG=none
TEST=test/mjsunit/debug-scopes.js
Review URL: http://codereview.chromium.org/123021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2149 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Two techniques are involved:
- compress repeated line ends (common stack beginnings) by using back references;
- do RLE compression of repeated tick events.
This gives only 5% size reduction on benchmarks run, but this is because tick events are only comprise 10% of file size. Under Chromium winnings are bigger because long repeated samples of idleness are now compressed into a single line.
Tickprocessor will be updated in the next patch.
Review URL: http://codereview.chromium.org/123012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2147 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Identify heap numbers that contain non-Smi int32s and do bit
ops on them without calling the fp hardware or emulation.
* Identify results that are non-Smi int32s and write them into
heap numbers without calling the fp hardware or emulation.
* Do unary minus on heap numbers without going into the runtime
system.
* On add, sub and mul if we have both Smi and heapnumber inputs
to the same operation then convert the Smi to a double and do
the op without going into runtime system. This also applies
if we have two Smi inputs but the result is not Smi.
Review URL: http://codereview.chromium.org/119241
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2131 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
instructions. The intention is that the snapshots generated
by the simulator should be usable on the hardware. Instead of
swi instructions we generate a branch to a swi instruction that
is not part of the snapshot. The call/jump is patched up in
the same way as other external references when the snapshot
is deserialized. This only works for EABI targets: on old ABI
targets we still emit some instructions not supported by the
simulator (fp coprocessor instructions).
Review URL: http://codereview.chromium.org/119036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2127 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is a trivial per-row compression:
- short aliases are introduced for events and code creation tags;
- in tick events, offsets are used instead of absolute addresses;
- removed 'code-allocation' event, as it seems not used.
The first two options are depend on the new flag: 'compress-log', which is off by default.
On benchmarks run w/o snapshot, this gives 45% log size reduction.
Review URL: http://codereview.chromium.org/119304
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2122 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Scripts now have a compilation type which can be host, eval or JSON. Host scripts are compiled through the API, eval scripts are compiled through call to evan and JSON scripts are compiled as a result of calling JSON.parse.
For scripts scripts compiled through eval the JavaScript function in top of the stack and the pc offset into the code is stored in the script object. This makes it possible to calculate the source position of the eval call later when requested. This information can be obtained through the script mirror object and is part of the script mirror JSON serialization for the debugger protocol.
Moved the enumeration ScripType into class Script and remamed to Type. The new compilation type enumeration is also inside the class Script.
This information is now shown when using the scripts command in he developer shell debugger.
Review URL: http://codereview.chromium.org/119108
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2119 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
interceptors and dont-delete attributes.
Minor change to the behavior of eval: throw exception when calling
eval in a context for which the global has been detached. This
matches the behavior of both Firefox and Safari post navigation in the
browser.
Review URL: http://codereview.chromium.org/118374
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2118 ce2b1a6d-e550-0410-aec6-3dcde31c8c00