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
Make esi available to the register allocator rather than dedicating it
permanently to the context.
The context is still passed in register esi to JavaScript and to the runtime
as part of the calling convention. Because some stubs might end up calling
JS or the runtime, it is also conservatively passed to stubs.
Roughly half the calls have been modified to use the context as an input
value in fixed register esi. The other half are marked as calls or deferred
code so esi is spilled and can be explicitly set.
It is no longer necessary to restore the context to esi after a call that
might change it.
Review URL: http://codereview.chromium.org/6452001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6713 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
There was an unnecessary load on every statically-resolved context lookup.
Remove it.
This revealed a hidden bug in const initializers inside 'with'. They claim
to be statically resolved (having slot type CONTEXT) but they occur in a
spot where the runtime context chain and the static scope chain do not
agree. This is fixed by special casing const initializers in the backend.
Review URL: http://codereview.chromium.org/6384020
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6635 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Change the ARM exit frame to have the same layout as the IA32 exit frame. This basically re-arranges the order of fp and sp and changes the sp location of the entry frame to hold the sp used by the gc and not the sp for popping the arguments. This removes the option of tearing down the frame and returning using one ldm instruction.
The main motivation for this is to avoid pushing an alignment word before generating the entry frame. The GC handling of optimized frames process the registers pushed as part of a safepoint and asumes that these are at the top of the frame, so if an alignment word is pushed this processing will be one off.
The alignment handling in the C entry stub have also been simplified. Now the value of lr is stored to a stack slot already reserved avoiding pushing it and keeping track of "frame skew".
This does result in more instructions in the exit frame on ARM, but we can look into improving this later.
Review URL: http://codereview.chromium.org/6247019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6448 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The the call of the builtin in InstanceofStub was not correctly protected with an internal frame leading to the return address being handled as a pointer during GC.
Marked the Instanceof stub as allowing stub calls (the RecordWriteStub was removed some days ago).
This issue was not caught by the assertion designed for this when debug mode is run with --debug-code (which out tests always does) as generating code for Abort set the allow stub calls flag to true. This has been fixed by restoring the allow stub calls flag correctly.
Review URL: http://codereview.chromium.org/6097010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6218 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
This adds a check to the fast case string add to ensure that the String object still have the default valueOf function. The default valueOf is sitting on a hidden prototype of String.prototype.
Before using the fast case valueOf the object is checked for a local valueOf property. For slow case objects this check always reports true (the dictionary is not probed, so valueOf might be there) and for fast case objects the descriptor array is checked for the valueOf symbol (just liniar scan). After that the prototype is checked for beeing the initial value of String.prototype. If this all pass (that is the default valueOf is still in place) this result is cached on the map making the check fast the next time.
This is only implemented in the optimizing compiler, as the two usages of %_IsStringWrapperSafeForDefaultValueOf is never hit by the full compiler.
I will port to x64 and ARM when this has been reviewed for ia32.
I will remove the performance counters prior to final commit.
BUG=http://code.google.com/p/v8/issues/detail?id=760
TEST=test/mjsunit/regress/regress-760-1.js
TEST=test/mjsunit/regress/regress-760-2.js
Review URL: http://codereview.chromium.org/3117006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5252 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
in allowing more flexible compilation and to simplify builtins lookup.
This changes a number of places where code objects are assigned to
SharedFunctionInfo objects to also assign this code object to the
JSFunction. In addition, the code flushing is changed slightly to
accomodate this (we need to flush the code from functions pointing to
SharedFunctionInfo objects that has already been flushed).
Review URL: http://codereview.chromium.org/3120006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5233 ce2b1a6d-e550-0410-aec6-3dcde31c8c00