Attempting to re-use the type feedback vector stored in the
SharedFunctionInfo turns out to be difficult among the various cases.
It will be much easier to do this when deferred type feedback processing
is removed, as is in the works.
Created bug v8:3212 to track re-introducing the optimization of reusing
the type vector on recompile before optimization.
The CL also brings back the type vector on the SharedFunctionInfo.
BUG=351257
LOG=Y
R=bmeurer@chromium.org, bmeuer@chromium.org
Review URL: https://codereview.chromium.org/199973004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19919 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The %_OneByteSeqStringSetChar intrinsic expects its arguments to be checked before being called for efficiency reasons, but the fuzzer provided no such checks. Now the intrinsic is robust to bad input if FLAG_debug_code is set.
R=yangguo@chromium.org
TEST=test/mjsunit/regress/regress-320948.js
BUG=chromium:320948
LOG=Y
Review URL: https://codereview.chromium.org/72813004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17886 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This patch fixes the step size of masm->pc_ in back_edge tables to words (4 bytes) to ensure 4 bytes alignment for read/write operations. Read and write of words (4 bytes) data from aligned space (address % 4 == 0) is more efficient on all platforms and especially on MIPS where without this alignment fix a kernel exception handler is used for every unaligned access.
This patch increases the size of back_edge tables by 3 bytes in every row. By the test it seem the back_edge table quite small in every/most cases (maximal length is 18 so in that case there are only 54 additional bytes with this patch).
BUG=
Patch from Douglas Leung <Douglas.Leung@imgtec.com>
Review URL: https://codereview.chromium.org/19248002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15782 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When a generator suspends, it saves its state out to the heap and
unwinds try handlers but doesn't pop anything off the stack. Instead it
relies on no GC happening between the suspend and the return from the
generator. However this was not the case: boxing the result object
could cause GC, which would try to traverse the stack but would
misinterpret words from unwound try handlers as heap objects.
This CL changes to allocate the result objects before the suspend. It
also removes the generators-iteration skip introduced in r15065.
R=mstarzinger@chromium.org
TEST=mjsunit/harmony/generators-iteration
BUG=
Review URL: https://codereview.chromium.org/16801006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15079 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The generator object methods "next", "send", and "throw" now
include some inline assembly to set up a resumed stack frame. In some
common cases, we can just jump back into the frame to resume it.
Otherwise the resume code calls out to a runtime to fill in the operand
stack, rewind the handlers, and possibly to throw an exception.
BUG=v8:2355
TESTS=mjsunit/harmony/generators-iteration
Review URL: https://codereview.chromium.org/14066016
Patch from Andy Wingo <wingo@igalia.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14415 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This reduces the time to run our test suite in debug mode considerably (from
8:43 to 4:05 on my local workstation using 32 threads). Note that the assertion
is so fast now that it doesn't need to be hidden behind --enable-slow-asserts.
Furthermore, the bookkeeping of the set is not measurable in all our benchmarks,
so I intentionally avoided any #ifdef chaos to keep things simple.
Review URL: https://codereview.chromium.org/11745027
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13312 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Modules now have their own local scope, represented by their own context.
Module instance objects have an accessor for every export that forwards
access to the respective slot from the module's context. (Exports that are
modules themselves, however, are simple data properties.)
All modules have a _hosting_ scope/context, which (currently) is the
(innermost) enclosing global scope. To deal with recursion, nested modules
are hosted by the same scope as global ones.
For every (global or nested) module literal, the hosting context has an
internal slot that points directly to the respective module context. This
enables quick access to (statically resolved) module members by 2-dimensional
access through the hosting context. For example,
module A {
let x;
module B { let y; }
}
module C { let z; }
allocates contexts as follows:
[header| .A | .B | .C | A | C ] (global)
| | |
| | +-- [header| z ] (module)
| |
| +------- [header| y ] (module)
|
+------------ [header| x | B ] (module)
Here, .A, .B, .C are the internal slots pointing to the hosted module
contexts, whereas A, B, C hold the actual instance objects (note that every
module context also points to the respective instance object through its
extension slot in the header).
To deal with arbitrary recursion and aliases between modules,
they are created and initialized in several stages. Each stage applies to
all modules in the hosting global scope, including nested ones.
1. Allocate: for each module _literal_, allocate the module contexts and
respective instance object and wire them up. This happens in the
PushModuleContext runtime function, as generated by AllocateModules
(invoked by VisitDeclarations in the hosting scope).
2. Bind: for each module _declaration_ (i.e. literals as well as aliases),
assign the respective instance object to respective local variables. This
happens in VisitModuleDeclaration, and uses the instance objects created
in the previous stage.
For each module _literal_, this phase also constructs a module descriptor
for the next stage. This happens in VisitModuleLiteral.
3. Populate: invoke the DeclareModules runtime function to populate each
_instance_ object with accessors for it exports. This is generated by
DeclareModules (invoked by VisitDeclarations in the hosting scope again),
and uses the descriptors generated in the previous stage.
4. Initialize: execute the module bodies (and other code) in sequence. This
happens by the separate statements generated for module bodies. To reenter
the module scopes properly, the parser inserted ModuleStatements.
R=mstarzinger@chromium.org,svenpanne@chromium.org
BUG=
Review URL: https://codereview.chromium.org/11093074
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13033 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
mksnapshot or a VM that is booted from a snapshot. --debug-code
can still have an effect on stub and optimized code and it still
works on the full code generator when running without snapshots.
The deoptimizer generates full-code-generator code and relies on it having
the same layout as last time. This means that the code the full code
generator makes for the snapshot should be the same as the code it makes
later. This change makes the full code generator create more consistent
code between mksnapshot time and run time.
This is a bug fix and a step towards making the snapshot code more robust.
Review URL: https://chromiumcodereview.appspot.com/10834085
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@12239 ce2b1a6d-e550-0410-aec6-3dcde31c8c00