The ES.next draft rev 4 in section 11.13 reads:
It is a Syntax Error if the AssignmentExpression is contained in extended code
and the LeftHandSideExpression is an Identifier that does not statically resolve
to a declarative environment record binding or if the resolved binding is an
immutable binding.
This CL adds corresponding static checks for the immutable binding case.
TEST=mjsunit/harmony/block-const-assign
Review URL: http://codereview.chromium.org/8688007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10156 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
source code positions it gets from the program counter to recreate the scope
chain by reparsing the function or program.
This CL includes the following changes
* Adds source code positions for the assignment added by the rewriter.
* Run the preparser over global code first.
* Use the ScopeType from the ScopeInfo to determine if the code being debugged
is eval, function or global code instead of looking up the '.result' symbol.
TEST=mjsunit/debug-stepout-scope.js
Review URL: http://codereview.chromium.org/8590027
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10076 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
Original commit message:
Add a level of indirection to exception handler addresses.
To support deoptimization of exception handlers, the handler address in the
stack is converted to a pair of code object and an index into a separate
table of code offsets. The index part is invariant under deoptimization.
The index is packed into the handler state field so that handler size does
not change.
R=vegorov@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8538011
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9977 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To support deoptimization of exception handlers, the handler address in the
stack is converted to a pair of code object and an index into a separate
table of code offsets. The index part is invariant under deoptimization.
The index is packed into the handler state field so that handler size does
not change.
R=vegorov@chromium.org,fschneider@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8462010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9975 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Remove a couple of unused fields from the FunctionLiteral, ensure that all
the bools are packed.
* Rename SaveScope and LexicalScope in the parser.
* Use an enum to generate the numbers 0..N and the dependent count, rather
than static const ints. This is simpler to extend (coming in a future
change).
R=danno@chromium.org,keuchel@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/8505012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9933 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 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 also includes the two fixes from r9674 and r9675. Here's the diff
to the previous CL.
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -11133,17 +11133,26 @@ class ScopeIterator {
context_(Context::cast(frame->context())),
nested_scope_chain_(4) {
+ // Catch the case when the debugger stops in an internal function.
+ Handle<SharedFunctionInfo> shared_info(function_->shared());
+ if (shared_info->script() == isolate->heap()->undefined_value()) {
+ if (shared_info->scope_info()->HasContext()) Next();
+ return;
+ }
+
// Check whether we are in global code or function code. If there is a stack
// slot for .result then this function has been created for evaluating
// global code and it is not a real function.
// Checking for the existence of .result seems fragile, but the scope info
// saved with the code object does not otherwise have that information.
- int index = function_->shared()->scope_info()->
+ int index = shared_info->scope_info()->
StackSlotIndex(isolate_->heap()->result_symbol());
// Reparse the code and analyze the scopes.
ZoneScope zone_scope(isolate, DELETE_ON_EXIT);
- Handle<SharedFunctionInfo> shared_info(function_->shared());
Handle<Script> script(Script::cast(shared_info->script()));
Scope* scope;
if (index >= 0) {
Review URL: http://codereview.chromium.org/8344046
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9734 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
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
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
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
The debugger can be entered from the deferred stack check in optimized code. This can cause both lazy deoptimization and debugger deoptimization (setting the first break point and inspecting the stack for optimized code respectively). This required deoptimization support from the deferred stack check.
The lazy deoptimiztion call is inserted when the deferred code is done including restoring the registers. The bailout to the full code is the begining of the loop body as that is where the stack check is sitting in the optimized code. The bailout is not to the stack check in the full code as that is sitting at the end of the loop.
R=kmillikin@chromium.org
BUG=none
TEST=none
Review URL: http://codereview.chromium.org//7212025
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8535 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The catch variable is bound in the catch scope. For simplicity in this
initial implementation, it is always allocated even if unused and always
allocated to a catch context even if it doesn't escape. The presence of
catch is no longer treated as a with.
In this change, care must be taken to distinguish between the scope where a
var declaration is hoisted to and the scope where the initialization occurs.
R=ager@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/7280012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8496 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Detect the pattern in both, the full compiler and crankshaft and generate direct pointer
comparisons. Along the way I cleaned up 'typeof <expression> == <string literal>' comparisons
as well by lifting platform independent code and checking the symmetric case.
BUG=v8:1440
TEST=cctest/test-api.cc
Review URL: http://codereview.chromium.org/7216008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8420 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* AST Expression nodes get a separate testing ID to record type info in
ToBooleanStub later. This is necessary to avoid clashes with other uses of
already existing IDs.
* In order to avoid threading the condition expression through tons of places,
TestContexts carry it now with them. Note that we will probably only need the
testing ID of the expression, but having the whole thing at hand makes
debugging easier. Probably we will change this later...
Review URL: http://codereview.chromium.org/7046073
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8274 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce separate maps for function and with contexts. Use the function
context map for testing whether a context is a function context (global
contexts are no longer function contexts).
Split the paths for allocating with and catch contexts.
Rename some functions. Generally refactor code to make it simpler.
R=ager@chromium.org
BUG=
TEST=
Review URL: http://codereview.chromium.org/7003058
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8231 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Mainly, there were errors concerning blank lines before and after class access
control sections [whitespace/blank_line].
BEFORE an access control section (e.g. public:, private:) there should be a
blank line (except for the section right after the class declaration).
AFTER an access control section there should be no blank line.
TBR=ager@chromium.org
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8193 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Almost all uses were below Expression already, only a single use in IfStatement
had to be handled explicitly (probably an oversight from earlier changes?). This
is a small step towards a less ad-hoc handling of IDs in the front end.
Review URL: http://codereview.chromium.org/7054034
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8118 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
- mutual inlining strict and non-strict functions in crankshaft.
- assignment to undefined variable with eval in scope.
- propagation of strict mode through lazy compilation.
BUG=
TEST=test/mjsunit/strict-mode.js test/mjsunit/strict-mode-opt.js
Review URL: http://codereview.chromium.org/6814012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7561 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Crankshaft is now the default on all platforms. This is the first
patch on the way to removing the classic code generator from the
system.
This time with no removal of the crankshaft flag. --nocrankshaft is
not at all the same as --always-full-compiler which I had used instead
for testing. That was what caused timeouts on the buildbots because of
repeated attempts to optimize hot functions. It makes sense to keep
the crankshaft flag in case you want to run only with the full
compiler and with no adaptive compilation.
R=vitalyr@chromium.org
Review URL: http://codereview.chromium.org/6759070
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7486 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
In the cases where a global property cell cannot be used in the optimized code
use standard load ic to get the property instead of bailing out.
This is re-committing r7212 and r7215 which where reverted in r7239 with the addition of recoring the source position in the hydrogen code for the LoadGlobalCell instruction. To record that position an optional position field has been added to the variable proxy AST node.
Review URL: http://codereview.chromium.org/6758007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7474 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This allows fast calls and inlining of functions like:
var o = {f: function() { return "foo"; }}
o.f();
Object literals that contain function literals are initially created a dictionary mode
object and only transformed to fast properties once all properties are computed and
added. This allows us to create constant function properties for functions declared
inside the object literal. Function literals inside object literals are marked for
pretenuring so that they work as contant function properties.
Object literals without functions should just function as before.
Review URL: http://codereview.chromium.org/6240012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7283 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Worth mentioning:
- Specialized versions of pixel array and store/loads inside the generic stubs have been removed, since to have parity for all external arrays, 8 different versions would have to be inlined/checked.
- There's a new constant in v8.h for external arrays with pixel array elements.
Review URL: http://codereview.chromium.org/6546036
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7106 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Refactor construction of switch statements so it doesn't use class
HSubgraph.
There are also a few improvements. We do not use an auxiliary list of
comparisons because they're embedded as a linked list in the graph
under construction. We share a common break block for all breaks from
the same switch. We do not insert empty blocks unless necessary to
maintain edge-split form.
There is also a bug fix. The entry to a clause body is a potential
join and must have a join ID set, otherwise deoptimization within the
body can go to an unpredictable place in the unoptimized code.
Review URL: http://codereview.chromium.org/6650021
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7099 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Move strict mode flag from TemporaryScope to Scope so that it can be accessed from variable binding code.
Arguments do not alias in strict mode (ia32, x64 and arm, codegen and full codegen).
Hydrogen tolerates null arguments_shadow().
In codegen-<arch> arguments object is allocated eagerly to capture values before they get modified.
Review URL: http://codereview.chromium.org/6625048/
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7083 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
To avoid deopts a few extra changes were needed:
o Enable megamorphic state for special property loads on
primitives. We used to flip between monomorphic stubs.
o Extract pure string (no string wrapper support) version of the
string length stub.
Review URL: http://codereview.chromium.org/6334015
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6472 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- var eval | arguments
- catch (eval | arguments)
- 'with' is disabled
- function can't be named eval or arguments
Add FLAG_strict_mode
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6422 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
- var eval | arguments
- catch (eval | arguments)
- 'with' is disabled
- function can't be named eval or arguments
- function parameter name cannot be eval or arguments
- no duplicate parameter names allowed
Add FLAG_strict_mode
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6369 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Before, when we deoptimized after a branch we jumped to before the branch
was taken in the unoptimized code with a token value that indicated when
edge to take. There was a lot of machinery to track this value through the
short-circuit logical operations and logical negation, and to handle it
properly at inline function return sites. There was also machinery to
prevent incorrectly seeing this environment with the extra value never
actually materialized in the unoptimized code.
Instead, now we deoptimize directly to one of the targets of the branch.
Much but not yet all of the extra machinery has been removed or simplified.
The cost is that branching control structures (the looping statements, if
statements, conditional expressions, and the short-circuit binary logical
operations) need extra AST IDs to identify the branch targets.
Review URL: http://codereview.chromium.org/5908001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6049 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This fixes V8 issue 989.
Before, assignments used the AST ID of the assignment expression to
mark the side effect of the store, which became a target for
deoptimization bailout for code after the assignment. In effect
contexts this environment included the value of the assignment, which
was unexpected by the unoptimized code.
Now we introduce a new assignment ID for AST node types that include
an assignment (Assignment, CountOperation, and ForInStatement) and use
it for the side effect of the store.
Review URL: http://codereview.chromium.org/5682010
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5990 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Change more functions used by the Compiler class to have a uniform
interface: they get passed as argument an input/output pointer to a
CompilationInfo that they mutate if they succeed, and they return a
flag telling whether they succeeded.
Also, remove some unnecessary timers.
Review URL: http://codereview.chromium.org/3561012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5583 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
When inspecting an AST node in the debugger, it can be difficult to
find its concrete type. Add a "node_type" virtual function to all the
concrete AST nodes.
Use a macro to generate the definition of node_type as well as Accept
and the AsXXX type testing/casting functions.
Review URL: http://codereview.chromium.org/3431026
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5549 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
For some reason, the scope's arguments and arguments shadow were
variable proxies, which resulted in all references to the arguments
shadow being shared in the AST. This makes it hard to put per-node
state on the AST nodes.
I took the opportunity to remove Variable::AsVariable which has
confused people in the past, and to rename Variable::slot to the more
accurate Variable::AsSlot.
Review URL: http://codereview.chromium.org/3432022
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5517 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Added support for more precise break points when debugging and stepping. To achieve that additional nop instructions are inserted where breaking would otherwise be impossible. The number of nop instructions inserted are sufficient to make place for patching with a call to a debug break code stub. On Intel that is 5 nop's for 32-bit and 13 for 64-bit. Om ARM 3 nop instructions (12 bytes) are required.
In order to avoid inserting nop's in to many places a simple ast checker have been added to check whether there are breakable code in a statement or expression. If it is possible to break in an expression no additional break enabeling code is inserted.
Added break locations to the true and false part of a conditional expression.
Added stepping tests to cover more constructs.
These changes are only in the full compiler.
Changed the default value for the option --debugger in teh d8 shell from true to false. The reason for this is that with --debugger turned on the full compiler will be used for all code in when running d8, which can be unexpeceted.
Review URL: http://codereview.chromium.org/2693002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4820 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
of having a list of virtual frame pointers in the jump
target we have one virtual frame, which is the frame that
all have to merge to to branch to that frame. The virtual
frame in the JumpTarget is inside the JumpTarget, rather than
being an allocated object that is pointed to. Unfortunately
this means that the JumpTarget class has to be able to see
the size of a VirtualFrame object to compile, which in turn
lead to a major reorganization of related .h files. The
actual change of functionality in this change is intended
to be minimal (we now assert that the virtual frames match
when using JumpTarget instead of just assuming that they do).
Review URL: http://codereview.chromium.org/1961004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4631 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The stack check has been moved from the Accept function dispatching on
the AST node type, earlier to the Visit function dispatching on the
visitor type.
This allows very simple non-recursive visitors (not taking extra
arguments or returning values) via the convention of calling "Visit"
if one wants the stack check and "Accept" if one does not. Recursive
calls should all be via "Visit".
Review URL: http://codereview.chromium.org/1567007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4320 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The flow graph has been simplified to remove the special branch, join,
and exit nodes. All nodes are now basic blocks (possibly empty to
preserve edge-split form) with a distinguished entry and exit block.
Most trivial expressions are not added to the flow graph as
instructions. The assigned variable analyzer has been changed to
sometimes work right-to-left so that right subexpressions can be
marked as trivial.
The reaching definitions analysis has been temporarily removed, and
the analyses that depended on it (primitivity analysis, dead code
marking) as well.
Review URL: http://codereview.chromium.org/1530003
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4307 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
As part of aggressive dead code elimination, we initially assume all
flow-graph instructions are not live. We mark those that are critical
and recursively all their children. The children of variable
references (VariableProxies occurring as rvalues) include all their
reaching definitions.
Review URL: http://codereview.chromium.org/1159005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4246 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Previously we marked compare operations that occurred as for loop
conditions so as to avoid inlining the floating-point code for them.
Begin marking all expressions that occur as any loop condition
(because they are never dead code).
Review URL: http://codereview.chromium.org/1074009
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4227 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change adds a data-flow pass to statically determine
if a variable contains a primitive type.
It requires building the flow graph and computing reaching
definitions as pre-requisites. The analysis annotates all
VariableProxy nodes with the result.
Review URL: http://codereview.chromium.org/1132005
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4224 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change adds the option to peel off the first iteration of inner loops.
Loop peeling is off by default and can enabled by a flag. It also requires building a flow graph.
As part of this I added the possibility to clone AST nodes.
Review URL: http://codereview.chromium.org/998001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4205 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
IsPrimitive reflects that an expression's value is known statically to
be one of the ECMA-262-3 JS types other than Object (e.g., Undefined,
Null, Boolean, String, or Number).
The type conversions ToPrimitive, ToNumber, ToInteger, ToInt32,
ToUInt32, ToUint16, ToString, or ToObject cannot invoke user code for
primitive input values. ToObject throws a TypeError if its input is
Undefined or Null.
Review URL: http://codereview.chromium.org/912002
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4116 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reaching definitions in (RD_in) is initially empty for all nodes. Gen
and kill sets are computed. AST node numbers are used for nodes to
refer to their definition number.
Also: two small changes to flow graph printing. Children of branch
nodes are visited in right-to-left order when performing depth first
search. Instructions are numbered locally within blocks so as to not
destroy AST node number before printing (it's useful to print the
definition).
Review URL: http://codereview.chromium.org/876001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4107 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
A variable usage analysis pass was run on toplevel and lazily-compiled
code but never used. Remove this pass and the data structures it
builds.
The representation of variable usage for Variables has been changed
from a struct containing a (weighted) count of reads and writes to a
simple flag. VariableProxies are always used, as before. The unused
"object uses" is removed.
Review URL: http://codereview.chromium.org/669270
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4052 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The flow graph is built by walking the AST. Edges are labeled with
instructions (AST nodes). Normal nodes have a single predecessor edge and a
single (labeled) successor edge. Branch nodes are explicit, they have a
single predecessor edge and a pair of (unlabeled) successor edges. Merge
nodes are explicit, they have a pair of predecessor edges and a single
(unlabeled) successor edge.
There is a distinguished (normal) entry node and a distinguished (special)
exit node with arbitrarily many predecessor edges and no successor edges.
The graph is intended to support graph-based analysis and transformation.
Review URL: http://codereview.chromium.org/660449
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4051 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Add a (currently) syntactic predicate to AST expression nodes telling
whether they are 'trivial'. Trivial expressions have no side effects,
do not require storage to be allocated for them, and can be evaluated
out of order (because their value does not change between when they
are visited by the code generator as expressions in the AST and when
it is consumed).
Mark 'this' and literals as trivial. Allow them to be pushed on the
virtual frame. Make use of them to push 'this' more lazily in this
property assignments.
Review URL: http://codereview.chromium.org/647018
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3906 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change add simple local live variable information to
the fast code generator. It supports only AST nodes that
are accepted by the syntax checker.
Each variable use points to a variable definition structure
which contains the last use of the definition.
To determine whether a variable is live after a certain point
we can check whether its last use occurs later in the evaluation
order defined by the AST labeling number.
The new information is currently only printed out together with
the IR and not yet used for code generation.
Review URL: http://codereview.chromium.org/603004
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3839 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Support a binary operation (bitwise OR) so long as it's not nested in
the left subexpression. This ensures that the expression stack never
has height greater than two and so can be kept fully in registers.
The bounded expression stack height and the absence of any side
effects on the fast path allows us to still bailout out to the very
beginning of the function if any of our fast-path checks fail.
Review URL: http://codereview.chromium.org/594008
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3822 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
