- 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
A separate object type for the code cache have been added. This object has two different code caches. The first one (default_cache) is a fixed array organized in the same way as the as the code cache was before. The second cache (global_access_cache) is for code stubs to access the global object. This cache is organized as a hash table taking the property name and code flags as the key.
The reason for separating the global access stubs into a hash table representation is that the number of these is not bounded in the same was as the other types.
This is a remake of r3952 (http://codereview.chromium.org/652119) which have the additional ability to look for the index of code stubs for access to the global object.
BUG=http://code.google.com/p/v8/issues/detail?id=613
Review URL: http://codereview.chromium.org/717001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4066 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
A separate object type for the code cache have been added. This object has two different code caches. The first one (default_cache) is a fixed array organized in the same way as the as the code cache was before. The second cache (global_access_cache) is for code stubs to access the global object. This cache is organized as a hash table taking the property name and code flags as the key.
The reason for separating the global access stubs into a hash table representation is that the number of these is not bounded in the same was as the other types.
BUG=613
Review URL: http://codereview.chromium.org/652119
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3952 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1. Avoid using SKIP_WRITE_BARRIER when we don't have to (smis).
2. Check and document the remaining uses of SKIP_WRITE_BARRIER.
3. Only allow GetWriteBarrierMode when in an AssertNoAllocation scope.
The only functional change should be in DeepCopyBoilerplate where we
no longer use the write barrier mode (because of allocations). I'm
running benchmarks to see if this has a measurable impact on performance.
Review URL: http://codereview.chromium.org/558041
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3743 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
On 32-bit the maps are now aligned on a 32-byte boundary in order to encode more maps during compacting GC. The actual size of a map on 32-bit is 28 bytes making this change waste 4 bytes per map.
On 64-bit the encoding for compacting GC is now using more than 32-bits and the maps here are still pointer size aligned. The actual size of a map on 64-bit is 48 bytes and this change does not intruduce any waste.
My choice of 16 bits for kMapPageIndexBits for 64-bit should give the same maximum number of pages (8K) for map space. As maps on 64-bit are larger than on 32-bit the total number of maps on 64-bit will be smaller than on 32-bit. We could consider raising this to 17 or 18.
I moved the kPageSizeBits to globals.h as the calculation of the encoding really depended on this.
There are still an #ifdef/#endif in objects.h and this constant could be moved to globaks.h as well, but I kept it together with the related constants.
All the tests run in debug mode with additional options --gc-global --always-compact as well (except for a few tests on which also fails before this change when run with --gc-global --always-compact).
BUG=http://code.google.com/p/v8/issues/detail?id=524
BUG=http://crbug.com/29428
TEST=test/mjsunit/regress/regress-524.js
Review URL: http://codereview.chromium.org/504026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3481 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
For scripts originating from a call to eval the Script object used to hold a reference to the function from where the eval was called together with the code offset within that function of the eval call. This is used by the stack trace and is part of the debugger protocol. In order to avoid storing the function the script, the position within the script and the name of the function calling eval is stored instead. This avoids holding context dependent objects in the script object.
The calculation of the position of the eval in the script holding the eval is now done when the eval script is compiled as it is not possible to postpone this unless a reference is kept to the generated code for the function calling eval.
BUG=http://code.google.com/p/v8/issues/detail?id=528
TEST=cctest/test-api/Regress528
Review URL: http://codereview.chromium.org/450034
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3393 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Storing a JSArray in the Script object could cause an indirect reference from the compilation cache to a global object to be created. Now the line ends are only stored as a FixedArrya and when that is needed in JavaScript a JSArray copy is created. Changed some of the JavaScript code to cache the line ends in a local variable for better performance.
BUG=http://code.google.com/p/v8/issues/detail?id=528
TEST=test/test-api/Bug528
Review URL: http://codereview.chromium.org/434117
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3374 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The different length string types was used to encode the string length and the hash in one field. This is now split into two fields one for length and one for hash. The hash field still encodes the array index of the string if it has one. If an array index is encoded in the hash field the string length is added to the top bits of the hash field to avoid a hash value of zero.
On 32-bit this causes an additional 4 bytes to be used for all string objects. On 64-bit this will be half on average dur to pointer alignment.
Review URL: http://codereview.chromium.org/436001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3350 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
it in regular flat strings that are part of the snapshot.
After this change we don't need libraries-empty.cc any more. In
this change libraries-empty.cc is just a the same as libraries.cc
and the scons build builds it but does not use it. We can move
in stages to a situation where it is not generated at all for all
the build systems that we have.
Review URL: http://codereview.chromium.org/360050
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3238 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
