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
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
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
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
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
It is available platforms that have SSE 4.1 and allows us to handle
negative numbers without deoptimization. Before we would deoptimize
on negative inputs to Math.floor. x64 already uses this instruction.
* Change Math.floor unit test to make sure every test case gets
optimized by changing the source code for each test case.
* Fix HIR debug printing for some instructions.
Review URL: http://codereview.chromium.org/7628017
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8921 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If the input range is positive and the shift count is constant
we can replace >>> with >> to compute the output range.
For negative inputs, we can only compute a range if the
result always fits into a signed int32.
BUG=v8:1510
Review URL: http://codereview.chromium.org/7489043
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8735 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* src/hydrogen-instructions.h (HClampToUint8): Don't mark as having
flexible representation; instead the output is always an Integer32.
There is no input representation restriction, so we can still perform
input-specific truncation.
I tested by looking at the --print-code of
var a = PixelArray(1000000)
function fill(a,x) { for (var i=0; i<a.len; i++) a[i] = x; }
Seems to optimize fine both for double and integer inputs. But perhaps
there is a better test, for which the original code does better, and
this is a bogus patch.
Review URL: http://codereview.chromium.org/7357003
Patch from Andy Wingo <wingo@igalia.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8650 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* src/hydrogen.cc (HInferRepresentation::Analyze): Fix iterative loop
over phis; the shortcutting behavior of || appears to be accidental
here, causing O(n^2) convergence. Not that it matters much, but hey!
While I'm at it, a minor comment fix:
* src/hydrogen-instructions.h (EnsureAndPropagateNotMinusZero): Fix a
comment about the kinds of instructions that propagate to multiple
inputs.
BUG=
TEST=passes tools/test.py
Review URL: http://codereview.chromium.org/7350019
Patch from Andy Wingo <wingo@igalia.com>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8645 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Eliminates the enum flag RESTORE_CONTEXT and CONTEXT_ADJUSTED, and adds a context HValue and LOperand to many hydrogen and lithium instructions.
Context is still used from the stack from in CallKnownFunction (this seems safe), and in CallRuntimeFromDeferred in lithium-codegen-ia32.cc, which needs to be fixed.
BUG=
TEST=
Review URL: http://codereview.chromium.org/7132002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8529 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The hydrogen stack check instruction is now added to each loop and the stack check handling on the back edge has been removed.
This change causes regression on small tight loops as the stack check is now at the top of the loop instead of at the bottom, and that requires one additional unconditional jump per loop iteration. However the reason for this change is to avoid worse regressions for upcoming changes to correctly support debugger break in optimized code.
R=fschneider@chromium.org
BUG=none
TEST=none
Review URL: http://codereview.chromium.org//7216009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8428 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change makes the number of successors of a control instruction
configurable with a template parameter and changes the existing instructions
to use it.
To iterate over all successors I added an iterator instead of always calling
First- and SecondSuccessor.
Review URL: http://codereview.chromium.org/7114004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8262 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
If type-feedback indicates that an expression was never executed in
the non-optimized code, we insert a forced deoptimization right away
to enable re-optimization if we ever hit this path.
With this change we still continue to build the graph. As a next step, we
should remove the dead code after the deoptimize.
I had to remove one assert about the optimization status in a test since
we now immediately deoptimize after exiting the loop that triggers OSR.
Also remove a restriction that control-flow from an inlined function in a
test context always reaches both true- and false-target.
Review URL: http://codereview.chromium.org/7105015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8140 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- Introduce a class JSReceiver, that is a common superclass of JSObject and
JSProxy. Use JSReceiver where appropriate (probably lots of places that we
still have to migrate, but we will find those later with proxy test suite).
- Move appropriate methods to JSReceiver class (SetProperty,
GetPropertyAttribute, Get/SetPrototype, Lookup, and so on).
- Introduce new JSFunctionProxy subclass of JSProxy. Currently only a stub.
- Overhaul enum InstanceType:
* Introduce FIRST/LAST_SPEC_OBJECT_TYPE that ranges over all types that
represent JS objects, and use that consistently to check language types.
* Rename FIRST/LAST_JS_OBJECT_TYPE and FIRST/LAST_FUNCTION_CLASS_TYPE
to FIRST/LAST_[NON]CALLABLE_SPEC_OBJECT_TYPE for clarity.
* Eliminate the overlap over JS_REGEXP_TYPE.
* Also replace FIRST_JS_OBJECT with FIRST_JS_RECEIVER, but only use it where
we exclusively talk about the internal representation type.
* Insert JS_PROXY and JS_FUNCTION_PROXY in the appropriate places.
- Fix all checks concerning classification, especially for functions, to
use the CALLABLE_SPEC_OBJECT range (that includes funciton proxies).
- Handle proxies in SetProperty (that was the easiest part :) ).
- A few simple test cases.
R=kmillikin@chromium.org
Review URL: http://codereview.chromium.org/6992072
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8126 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The approach is to handle the common case in the optimizing
compiler and to bailout for the rare corner cases.
This is done by initializing all local const-variables with
the hole value and disallowing any use of the hole value statically.
Review URL: http://codereview.chromium.org/6026006
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8104 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