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
The problem appeared due to a fact that stubs doesn't create a stack
frame, reusing the stack frame of the caller function. When building
stack traces, the current function is retrieved from PC, and its
callees are retrieved by traversing the stack backwards. Thus, for
stubs, the stub itself was discovered via PC, and then stub's caller's
caller was retrieved from stack.
To fix this problem, a pointer to JSFunction object is now captured
from the topmost stack frame, and is saved into stack trace log
record. Then a simple heuristics is applied whether a referred
function should be added to decoded stack, or not, to avoid reporting
the same function twice (from PC and from the pointer.)
BUG=553
TEST=added to mjsunit/tools/tickprocessor
Review URL: http://codereview.chromium.org/546089
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3673 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Instead of going through a runtime function for keyed loads
on strings we invoke a separate specialized stub that
assumes string as receiver type and the key to be a number.
The stub calls a JS builtin function to return the corresponding one-character string.
Review URL: http://codereview.chromium.org/521041
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3556 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added a stub to allocate and fill a string object with a substring from another string.
Use the rep movs instruction to copy the string data as it turned out to be the fastest way.
While preparing this I experimented with some SSE2 instructions, so the instructions movdqa and movdqu are still in the IA-32 assembler even though they are not used.
Review URL: http://codereview.chromium.org/525085
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3554 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When generating code for object and array literals we performed
the check if the a boilerplate already exists in generated code.
In the top-level compiler we now do this check in a new runtime
function. This makes the generated code more compact for top-level code.
Review URL: http://codereview.chromium.org/465148
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3437 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This adds a code stub which can do most of what Heap::AllocateConsString can do. It bails out if the result cannot fit in new space or if the result is a short (flat) string and one argument is an ascii string and the other a two byte string. It also bails out if adding two one character strings as Heap::AllocateConsString has special handling of this utilizing the symbol table. The stub is used both for the binary add operation and for StringAdd calls from runtime JavaScript files. Extended the string add test to cover all sizes of flat result stings.
Review URL: http://codereview.chromium.org/442024
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3400 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
potentially leading to bogus FatalProcessOutOfMemory situations. Also
fixed a few cases where callers relied on getting a NewSpace object
back (to avoid write barrier overhead) which they can't when
always_allocate is in effect.
Review URL: http://codereview.chromium.org/391018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3285 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
String slices from RegExp replace results is now encoded in either one or two smis. Substrings are not used any more.
If the existing one smi encoding cannot hold the start/length information two smis are used the first having the negative length and the second having the start.
This is in preparation for removing string slices.
Review URL: http://codereview.chromium.org/342015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3153 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
of individual changes:
- Added infrastructure for custom stub caching.
- Push the code object onto the stack in exit calls instead of a
debug/non-debug marker.
- Remove the DEBUG_EXIT frame type.
- Add a new exit stub generator for API getters.
Review URL: http://codereview.chromium.org/330017
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3130 ce2b1a6d-e550-0410-aec6-3dcde31c8c00