So far we had two types of stack checks: one used for function entries
and one used at loop back edges which uses a deferred code object to
avoid spilling of registers in the loop.
After refactoring lazy deoptimization the first stack check can also
use deferred code. This change removes the first type of stack check
instruction in Crankshaft and uses a deferred stack check in all
places.
Review URL: http://codereview.chromium.org/8775002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10118 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This CL introduces a third mode next to the non-strict
(henceforth called 'classic mode') and 'strict mode'
which is called 'extended mode' as in the current
ES.next specification drafts. The extended mode is based on
the 'strict mode' and adds new functionality to it. This
means that most of the semantics of these two modes
coincide.
The 'extended mode' is entered instead of the 'strict mode'
during parsing when using the 'strict mode' directive
"use strict" and when the the harmony-scoping flag is
active. This should be changed once it is fully specified how the 'extended mode' is entered.
This change introduces a new 3 valued enum LanguageMode
(see globals.h) corresponding to the modes which is mostly
used by the frontend code. This includes the following
components:
* (Pre)Parser
* Compiler
* SharedFunctionInfo, Scope and ScopeInfo
* runtime functions: StoreContextSlot,
ResolvePossiblyDirectEval, InitializeVarGlobal,
DeclareGlobals
The old enum StrictModeFlag is still used in the backend
when the distinction between the 'strict mode' and the 'extended mode' does not matter. This includes:
* SetProperty runtime function, Delete builtin
* StoreIC and KeyedStoreIC
* StubCache
Review URL: http://codereview.chromium.org/8417035
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10062 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This generates optimized code for deep-copying of nested object literal
boilerplates which are statically known. Most of the boilerplates have
already been generated at crankshaft time, so this optimization should
kick in for virtually every object literal. Only nested object literal
graphs up to a certain depth and containing up to a certain total number
of properties are considered for this optimization. This will prevent
explosion of code size due to large object literals (e.g. eval on JSON).
Improves splay performance because object literals are created often.
R=fschneider@chromium.org
Review URL: http://codereview.chromium.org/8640001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10061 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In case of a degenerated CFG like in the example below processing
predecessors in the wrong order yields n^2 runtime.
do {
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
if (x) break;
// etc.
} while (false);
Reversing iteration order avoids this.
Review URL: http://codereview.chromium.org/8502012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9905 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This was pretty heavyweight. It was kept in just for a few corner cases
that assumed it was there. We can work around them by making sure that the
expression in a reified test context is always really the expression that
was visited in that context; and by inspecting the context manually and
consing up a pair of extra AST IDs for the unusual case of unary not in a
value AST context.
R=fschneider@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8386037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9863 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change fixes a off-by-one level error when dropping the
function from the environment. The function of the outermost
environment was not dropped.
BUG=v8:1785
TEST=test/mjsunit/compiler/regress-inline-callfunctionstub.js
Review URL: http://codereview.chromium.org/8341019
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9789 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This implements block scoped 'const' declared variables in harmony mode. They
have a temporal dead zone semantics similar to 'let' bindings, i.e. accessing
uninitialized 'const' bindings in throws a ReferenceError.
As for 'let' bindings, the semantics of 'const' bindings in global scope is not
correctly implemented yet. Furthermore assignments to 'const's are silently
ignored. Another CL will introduce treatment of those assignments as early
errors.
Review URL: http://codereview.chromium.org/7992005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9764 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change is based on my previous change enabling inlining calls-as-function
fixing the bugs related to deoptimization.
The function value on top of the environment was dropped too late in the old code.
As a result we could get a wrong value on top after deoptimization.
This change includes r9619. It was reverted because of test failures that are fixed
with this patch.
Review URL: http://codereview.chromium.org/8360001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9758 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Named function expression have an implicit local variable that
refers to the current function (ThisFunction). Before we only could inline
anonymous function expressions like:
A.prototype.foo = function() {}
as opposed to
A.prototype.foo = function foo() {}
This change enables inlining function of expressions like this.
Review URL: http://codereview.chromium.org/8346032
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9699 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This time, we initially leave the HTypeof instruction in the Hydrogen graph,
even for the special cases. We later try to remove this instruction (and any
HConstant) in the canonicalization pass, if possible. Always removing the
HTypeof during the initial graph construction is wrong if e.g. it is used in an
HSimulate.
The removals can be generalized a bit, but this will happen in a separate CL.
TEST=mjsunit/optimized-typeof.js
Review URL: http://codereview.chromium.org/8334021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9688 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
1. Record AST id for CallFunctionStub.
2. Correctly extract cached target from CallFunctionStub inline cache.
3. Fix a bug when inling call as a function in effect or value context:
Handle abnormal exits correcty.
4. Fix a bug when inlining call as a function in test context: drop function
correctly from true and false block.
5. Avoid inlining mutually recursive functions by checking the stack of function
states before inlining. This was not a bug, but is just a more general
check to avoid recursive inlining.
Review URL: http://codereview.chromium.org/8258012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9619 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Previously, comparisons against null/undefined and comparisons of the result of
typeof against a constant string were done syntactically. Now we do this via
pattern matching on the hydrogen graph, which opens up more opportunities for
better code generation, e.g. the following comparisons are now recognized to be
special:
var bar = typeof foo;
var baz = "undefined";
if (bar == baz) ...
var blah = undefined;
if (hurz == blah) ...
If we did this handling of special cases even later at lithium generation time,
even more cases could be recognized, but this would involve bigger changes and
this CL handles most common cases.
Review URL: http://codereview.chromium.org/8242002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9612 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This eliminates compile-errors when assigning Handle<SerializedScopeInfo> to
Handle<Object> in a place where the declaration was not available because
variables.h was not included.
As a result I had to also move the enum Variable::Mode to v8globals.h and
rename it to VariableMode.
Review URL: http://codereview.chromium.org/8221004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9575 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Currently we avoid checking for the hole value after array loads, if the
result is only used by instructions that definitely deoptimize in case
of the hole value (HChange instructions).
This change performs the same procedure for loading from deleteable/read-only
global variable where we can also avoid the check in the same cases.
Review URL: http://codereview.chromium.org/8054008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9453 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
It's not safe to use an immediate heap object in generated unless we take
pains to ensure it's not in new space. Continue using the caller's context
for inlined functions on all platforms except IA32.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9427 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In some special (but probably very common) cases we can do better than loading
from a global cell for these global properties by emitting the corresponding
constant directly. This opens up opportunities for further improvements, coming
in a separate CL...
Review URL: http://codereview.chromium.org/7992002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9409 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
We have to check for uninitialized uses before phi-elimination. Otherwise we
may miss such a use and result in using the hole value instead. This
causes a NULL-dereference or assertion failure.
BUG=96989
TEST=mjsunit/compiler/regress-96989.js
Review URL: http://codereview.chromium.org/7974009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9337 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Although this patch is not small, most parts of it are rather mechanical:
* First of all, the concept of a 'nil-like' value is introduced, which can be
null or undefined. They are treated symmetrically regarding comparisons, so
it makes sense to handle them in a uniform manner. It is a mystery why
JavaScript defines two of those beasts, when even *one* is a design wart...
* Extended and renamed a few things which now handle undefined in addition to
null.
* Made the parts of the full code generator and the hydrogen generation which
deal with comparisons a bit more similar regarding their handling of special
cases.
* Refactored the syntactical detection of special cases for comparisons,
hopefully making them a bit more readable and less copy-n-paste-oriented.
Things like this should really be a one-liner in any sane programming
language... :-P
* Cut down the length of the argument lists of a few functions to something
less insane, making them more easily understandable locally. This involves
minor code duplication, but this was a good tradeoff and can be remedied
later if necessary.
* Replaced some boolean arguments with more readable enums.
* Fixed a TODO: Values which are definitely a Smi or unboxed can never be equal
to null or undefined.
Review URL: http://codereview.chromium.org/7918012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9323 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The Great Master Plan is to move the recognition of special cases for
comparisons further down the compilation pipeline where more information is
available. This is a first step into this direction: The special handling of
equality comparisons involving null is pushed from the parser to the code
generators, removing the need for a special AST node. (There are rumors from
usually well-informed sources that this node type is actually a relic of ancient
crankshaft days...)
The next steps will be the unification of null/undefined handling and pushing
the special case handling in crankshaft even further down the pipeline, enabling
the recognition of cases like "var foo=null; if (foo === bar) ...", but these
will be in separate CLs.
Review URL: http://codereview.chromium.org/7887037
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9293 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Removed an unneeded check for phis: There are never HValues in the work list
which are not convertible to integer and are not a phi. (But even if they were,
ignoring IsConvertibleToInteger() then looks like the wrong thing to do.)
Review URL: http://codereview.chromium.org/7857033
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9225 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Refactor Context::Lookup so it is more obvious. Change the comment in
contexts.h so it no longer indicates that it can return an arguments
object (it can't) and clean up the call sites that had leftover dead code.
BUG=
TEST=
Review URL: http://codereview.chromium.org/7782030
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9223 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When we propagate the information that a value is not convertible to integer,
there is no need for a separate fixed-point computation, we can do things the
"Millikin way" (tm), folding as much computation as possible into a single pass:
;-) We already have the phi node reachability information, so we can easily
propagate this while doing the representation histogram computation.
Review URL: http://codereview.chromium.org/7754010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9212 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The use-def relation between phis is mainly "forwards" (i.e. from phis with
smaller IDs to ones with larger IDs), so the fixed point computation terminates
faster when iterate through the phis in a "backwards" manner. This is quite
visible in complex Mandreel-generated code, where a few hundred phis with
non-trivial use-def chains are generated.
Review URL: http://codereview.chromium.org/7848012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9185 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The changes to scopes and parser introduce a VariableProxy
wrapping the function-name variable for function literals.
It seems the easiest way to get an AST id for the HSimulate
after context-slot stores in declarations.
Review URL: http://codereview.chromium.org/7826009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9112 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
We have to emit code for declarations later into the body block
(and not into the start block) so that the environment contains
the correct values.
In order to capture the environment effect of the declarations
that generate code (function declarations) I inserted a separate
AST id and a HSimulate after the declarations are visited.
Also fixes handling deopt in named function expressions:
BUG=v8:1647
TEST=test/mjsunit/regress/regress-fundecl.js, test/mjsunit/regress/regress-1647.js
Review URL: http://codereview.chromium.org/7776009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9083 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Changes GetGlobalReceiver() to GetDefaultReceiver(func) that returns undefined
for strict and native functions, and the function's context's global proxy
for "normal" functions.
BUG=v8:1547
TEST=cctest/api-test/ForeignFunctionReceiver
Review URL: http://codereview.chromium.org/7741042
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9030 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This eliminate redundant HChange instructions and allows range information of
converted values propagated across control-flow splits.
It fixes the performance regression on code like:
if (x > 1) {
y = x - 1;
}
where we should eliminate the overflow check on the sub inside the if-statement.
Review URL: http://codereview.chromium.org/7709025
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8997 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This improves our static type information by calculating the result type
of conversions (HChange) during range analysis. It allows e.g. to eliminate
the write barrier in the following example where it was not possible before:
function f(x) {
var y = x + 1;
if (y > 0 && y < 100) {
a[0] = y;
}
}
* Fix bug in Range::Copy. The minus-zero flags has to be preserved by default.
Review URL: http://codereview.chromium.org/7634022
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8994 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Some AST nodes (Property, Call, etc.) store either a list of receiver
types or a monomorphic receiver type. This patch merges the two fields
using a small pointer list. GetMonomorphicReceiverType() is now a
purely convenience function returning the first and only recorded
type.
This saves about 500K (of about 39M) on average when compiling V8
benchmark as measured by a simple patch adding a zone allocation
counter (https://gist.github.com/1149397).
R=kmillikin@chromium.org
Review URL: http://codereview.chromium.org/7655017
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8993 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Remove the try/finally used for with and catch. Instead of using
try/finally to handle break and continue from with or catch,
statically track nesting dept and clean up when compiling break or
continue.
And instead of using try/finally to handle throw to handler in a frame
whose pc is inside a with or catch, store the context that the handler
should run in in the handler itself.
BUG=
TEST=
Review URL: http://codereview.chromium.org/7618007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8922 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
HGraphBuilder::TryArgumentsAccess does not emit any uses for receiver and will generate incorrect code when receiver for a property access is defined by a phi that returns either arguments object or something else.
BUG=v8:1582
TEST=test/mjsunit/regress/regress-1582.js
Review URL: http://codereview.chromium.org/7553006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8774 ce2b1a6d-e550-0410-aec6-3dcde31c8c00