1) Don't make a call to C without having a valid frame on the stack.
2) Don't generate a call to a stub while generating a stub, unless we can be
sure that the stub we are calling has already been generated (the stub
generation code is not reentrant wrt. GC).
Review URL: http://codereview.chromium.org/7891042
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9297 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Only IA32 version for now. I'll start porting.
Strict mode functions are to get 'undefined' as the receiver when
called with an implicit receiver. Modes are bad! It forces us to have
checks on all function calls.
This change attempts to limit the cost by passing information about
whether or not a call is with an implicit or explicit receiver in ecx
as part of the calling convention. The cost is setting ecx on all
calls and checking ecx on entry to strict mode functions.
Implicit/explicit receiver state has to be maintained by ICs. Various
stubs have to not clobber ecx or save and restore it.
CallFunction stub needs to check if the receiver is implicit when it
doesn't know from the context.
Review URL: http://codereview.chromium.org/7039036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8040 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Better support for 'polymorphic' JS and external arrays
Allow keyed store/load stubs to switch between external array and fast JS arrays without forcing a state transition to the generic stub.
There CL consists of two pieces of functionality. First, code stubs for fast element arrays don't immediately transition to the MEGAMORPHIC state when there's a map mismatch. Second, two ICs are cached per map for fast elements, the MONOMORPHIC version, and a new MEGAMORPHIC version that handles two or more different maps and dispatches to shared stubs to perform the array operation.
Review URL: http://codereview.chromium.org/7036016
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7935 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Allow keyed store/load stubs to switch between external array and fast JS arrays without forcing a state transition to the generic stub.
There CL consists of two pieces of functionality. First, code stubs for fast element arrays don't immediately transition to the MEGAMORPHIC state when there's a map mismatch. Second, two ICs are cached per map for fast elements, the MONOMORPHIC version, and a new MEGAMORPHIC version that handles two or more different maps. Currently, the only array types supported by the MEGAMORPHIC stub are fast elements for objects and JSArrays.
BUG=
TEST=
Review URL: http://codereview.chromium.org/6894003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7917 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is IA32 only for now.
Added a random value to each assembler instance (JIT cookie) to be used for constant splitting. Added safe versions of setting a register with an immediate value and for pushing an immediate value. Used these functions where user controlled immediate values could be emitted in the code stream. I also used it for immediates which are an argument number even though the number of formal arguments is currently limited to 16k.
I found no compares directly with user controlled constants.
I am not sure whether the test is that useful, but it might catch some changes missing constant splitting.
Review URL: http://codereview.chromium.org//7005031
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7868 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Ensure that there is always enough bytes between consequtive calls in
unoptimized code to write a call instruction at the return points
without overlapping.
This handles the case where two return points were only four bytes
apart (because the latter call was to a register).
BUG=v8:1234
Review URL: http://codereview.chromium.org/6624091
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7089 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
inline allocation code used the expected number of properties to
calculate the number of inobject properties for an object instead of
getting the actual number from the initial map.
It is safer to use the inobject property count from the initial map in
any case because that is the amount the instances will get. I think
this disconnect got introduced when adding shrinking of objects.
Unfortuntely I haven't been able to create a simple reproduction for a
test case but this fixes the webpage that exhibits the crash. I'll see
if I can create a reproduction tomorrow.
Review URL: http://codereview.chromium.org/5278003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5879 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The live registers are now only stored to the expression stack with the non pointer values being stored as smis (on the 32-bit platforms these values are assumed to be 31-bit max).
This makes the CEntryStub entry/exit code much simpler, and there is no longer any need for a mode (debug or normal) on it.
Fix a missing live register when breaking at ARM keyed load.
Review URL: http://codereview.chromium.org/3141047
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5358 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Object model changes
----------------------------------------
New fixed_cow_array_map is used for the elements array of a JSObject
to mark it as COW. The JSObject's map and other fields are not
affected. The JSObject's map still has the "fast elements" bit set. It
means we can do only the receiver map check in keyed loads and the
receiver and the elements map checks in keyed stores. So introducing
COW arrays doesn't hurt performance of these operations. But note that
the elements map check is necessary in all mutating operations because
the "has fast elements" bit now means "has fast elements for reading".
EnsureWritableFastElements can be used in runtime functions to perform
the necessary lazy copying.
Generated code changes
----------------------------------------
Generic keyed load is updated to only do the receiver map check (this
could have been done earlier). FastCloneShallowArrayStub now has two
modes: clone elements and use COW elements. AssertFastElements macro
is added to check the elements when necessary. The custom call IC
generators for Array.prototype.{push,pop} are updated to avoid going
to the slow case (and patching the IC) when calling the builtin should
work.
COW enablement
----------------------------------------
Currently we only put shallow and simple literal arrays in the COW
mode. This is done by the parser.
Review URL: http://codereview.chromium.org/3144002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5275 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The IC stub is completely generic, so there will only be one such stub
in the system.
Added a new overloaded version of the macro assembler RecordWrite
method for cases where we have the address we store to computed up
front.
Review URL: http://codereview.chromium.org/2804029
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4991 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- 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
This change adds a pass over the AST that computes the
set of assigned variables for locals and parameters for each expression.
The result of this analysis is used to for two purposes:
1. Recognize variables that are trivial subexpressions. A left sub-expression
of a binary operation is trivial if it is a local variable or a parameter
and it is not assigned in the right sub-expression. In the case of a
trivial left sub-expression we evaluate the right first.
Currently only binary operations and compare operations are considered
when finding trivial left sub-expressions.
2. Recogize certain simple for-loops with a constant trip count where the loop
variable is always within smi range. If the loop count variable is not
assigned in the body of the loop (except in the update expression the
for-loop). This allows omitting smi checks on operation using the loop
count variable.
Review URL: http://codereview.chromium.org/669155
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4087 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Each frame element gets a new attribute with number type information. A frame element can be:
- smi
- heap number
- number (i.e. either of the above)
- or something else.
The type information is propagated along with all virtual frame operations.
Results popped from the frame carry the number information with them.
Two optimizations in the code generator make use of the new
information:
- GenericBinaryOpSyub omits map checks if input operands are numbers.
- Boolean conversion for numbers: Emit inline code for converting a number (smi or heap number) to boolean. Do not emit call to ToBoolean stub in this case.
Review URL: http://codereview.chromium.org/545007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3861 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
All two character string results from adding two strings and from sub string used to be handled in the runtime system as a lookup in the symbol table was done before allocating a new string. The native code for string add and sub string now probes the symbol cache for two character strings to avoid the runtime call. If the result string is not found in the symbol table within a fixed number of probes a new string is just allocated. Newly allocated two character strings are not added to the symbol table immediately.
Review URL: http://codereview.chromium.org/598062
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3842 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
function instead of baking in the address of the first one that we see
in code.
This removes the need for fixups processing and makes the stubs safe
when there is no natives cache and therefore multiple versions of the
builtin functions.
Review URL: http://codereview.chromium.org/594009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3832 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
