This implements correct semantics for "extensible" top level lexical scope.
The entire lexical scope is represented at runtime by GlobalContextTable, reachable from native context and accumulating global contexts from every script loaded into the context.
When the new script starts executing, it does the following validation:
- checks the GlobalContextTable and global object (non-configurable own) properties against the set of declarations it introduces and reports potential conflicts.
- invalidates the conflicting PropertyCells on global object, so that any code depending on them will miss/deopt causing any contextual lookups to be reexecuted under the new bindings
- adds the lexical bindings it introduces to the GlobalContextTable
Loads and stores for contextual lookups are modified so that they check the GlobalContextTable before looking up properties on global object, thus implementing the shadowing of global object properties by lexical declarations.
R=adamk@chromium.org, rossberg@chromium.org
Review URL: https://codereview.chromium.org/705663004
Cr-Commit-Position: refs/heads/master@{#25220}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25220 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
During generation code and relocation info are generated simultaneously.
When code generation is done you each code object has associated "relocation info".
Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
correspondences between the machine program counter and source locations for stack walking.
This patch:
1. Add more source positions info in reloc info to make it suitable for source level mapping.
The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
(2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
If a source line is found that hit counter is increased by one for this line.
3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
4.Add a test that checks how the samples are distributed through source lines.
It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
Patch from Denis Pravdin <denis.pravdin@intel.com>;
R=svenpanne@chromium.org, yurys@chromium.org
Review URL: https://codereview.chromium.org/682143003
Patch from Weiliang <weiliang.lin@intel.com>.
Cr-Commit-Position: refs/heads/master@{#25182}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25182 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Updates Object.prototype.toString() to use algorithm described in harmony drafts.
Currently, the behaviour is essentially the same as ES262's version, however this changes when internal structures
such as Promise make use of symbolToStringTag (as they are supposed to, see v8:3241), and changes further once
Symbol.toStringTag is exposed publicly.
BUG=v8:3241, v8:3502
LOG=N
R=dslomov@chromium.org
Review URL: https://codereview.chromium.org/546803003
Patch from Caitlin Potter <caitpotter88@gmail.com>.
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24783 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reason for revert:
It broke layout test fast/events/window-onerror-02.html, error column reported by window.onerror is now wrong (I believe it is because of the change in full-codegen):
http://build.chromium.org/p/client.v8/builders/V8-Blink%20Linux%2064%20%28dbg%29/builds/652
Original issue's description:
> Extend CPU profiler with mapping ticks to source lines
>
> The idea behind of this solution is to use the existing "relocation info" instead of consumption the CodeLinePosition events emitted by the V8 compilers.
> During generation code and relocation info are generated simultaneously.
> When code generation is done you each code object has associated "relocation info".
> Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
> correspondences between the machine program counter and source locations for stack walking.
>
> This patch:
> 1. Add more source positions info in reloc info to make it suitable for source level mapping.
> The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
> (2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
> I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
>
> 2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
> If a source line is found that hit counter is increased by one for this line.
>
> 3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
> Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
>
> 4.Add a test that checks how the samples are distributed through source lines.
> It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
>
> Patch from Denis Pravdin <denis.pravdin@intel.com>
> BUG=None
> LOG=Y
> R=svenpanne@chromium.org
>
> Committed: https://code.google.com/p/v8/source/detail?r=24389TBR=svenpanne@chromium.org,danno@chromium.org,alph@chromium.org,denis.pravdin@intel.com,weiliang.lin@intel.com
BUG=None
LOG=N
Review URL: https://codereview.chromium.org/624443005
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24394 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The idea behind of this solution is to use the existing "relocation info" instead of consumption the CodeLinePosition events emitted by the V8 compilers.
During generation code and relocation info are generated simultaneously.
When code generation is done you each code object has associated "relocation info".
Relocation information lets V8 to mark interesting places in the generated code: the pointers that might need to be relocated (after garbage collection),
correspondences between the machine program counter and source locations for stack walking.
This patch:
1. Add more source positions info in reloc info to make it suitable for source level mapping.
The amount of data should not be increased dramatically because (1) V8 already marks interesting places in the generated code and
(2) V8 does not write redundant information (it writes a pair (pc_offset, pos) only if pos is changed and skips other).
I measured it on Octane benchmark - for unoptimized code the number of source positions may achieve 2x ('lin_solve' from NavierStokes benchmark).
2. When a sample happens, CPU profiler finds a code object by pc, then use its reloc info to match the sample to a source line.
If a source line is found that hit counter is increased by one for this line.
3. Add a new public V8 API to get the hit source lines by CDT CPU profiler.
Note that it's expected a minor patch in Blink to pack the source level info in JSON to be shown.
4.Add a test that checks how the samples are distributed through source lines.
It tests two cases: (1) relocation info created during code generation and (2) relocation info associated with precompiled function's version.
Patch from Denis Pravdin <denis.pravdin@intel.com>
BUG=None
LOG=Y
R=svenpanne@chromium.org
Review URL: https://codereview.chromium.org/616963005
Patch from Denis Pravdin <denis.pravdin@intel.com>.
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24389 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
