Previously, name conflicts between var and let declarations were only
made into exceptions if they were visible at parse-time. This patch adds
runtime checks so that sloppy-mode direct eval can't introduce conflicting
var declarations. The change is implemented by traversing the scope chain
when a direct eval introduces a var declaration to look for conflicting
let declarations, up to the function boundary.
BUG=v8:4454
R=adamk
LOG=Y
Review URL: https://codereview.chromium.org/1382513003
Cr-Commit-Position: refs/heads/master@{#31211}
This fixes the Runtime_DeclareGlobals performance regression caused by a huge number of global var declarations mentioned in chromium:517778.
BUG=chromium:517778
LOG=N
Review URL: https://codereview.chromium.org/1335633002
Cr-Commit-Position: refs/heads/master@{#30679}
This CL us a pure refactoring that makes an empty compilation unit
including just "isolate.h" or "contexts.h" but not "objects-inl.h"
compile without warnings or errors. This is needed to further reduce
the header dependency tangle.
R=bmeurer@chromium.org
Review URL: https://codereview.chromium.org/1322883002
Cr-Commit-Position: refs/heads/master@{#30500}
This CL introduces HPrologue instruction which does the context allocation work and supports deoptimization.
Review URL: https://codereview.chromium.org/1317383002
Cr-Commit-Position: refs/heads/master@{#30496}
This CL is a nightmare! For the utterly irrelevant edge case of a sloppy function with non-simple parameters and a call to direct eval, like here,
let x = 1;
function f(g = () => x) {
var y
eval("var x = 2")
return g() + x // f() = 3
}
we have to do all of the following, on top of the declaration block ("varblock") contexts we already introduce around the body:
- Introduce the ability for varblock contexts to have both a ScopeInfo and an extension object (e.g., the body varblock in the example will contain both a static var y and a dynamic var x). No other scope needs that. Since there are no context slots left, a special new struct is introduced that pairs up scope info and extension object.
- When declaring lookup slots in the runtime, this new struct is allocated in the case where an extension object has to be added to a block scope (at which point the block's extension slot still contains a plain ScopeInfo).
- While at it, introduce some abstraction to access context extension slots in a more controlled manner, in order to keep special-casing to a minimum.
- Make sure that even empty varblock contexts do not get optimised away when they contain a sloppy eval, so that they can host the potential extension object.
- Extend dynamic search for declaration contexts (used by sloppy direct eval) to recognize varblock contexts.
- In the parser, if a function has a sloppy direct eval, introduce an additional varblock scope around each non-simple (desugared) parameter, as required by the spec to contain possible dynamic var bindings.
- In the pattern rewriter, add the ability to hoist the named variables the pattern declares to an outer scope. That is required because the actual destructuring has to be evaluated inside the protecting varblock scope, but the bindings that the desugaring introduces are in the outer scope.
- ScopeInfos need to save the information whether a block is a varblock, to make sloppy eval calls work correctly that deserialise them as part of the scope chain.
- Add the ability to materialize block scopes with extension objects in the debugger. Likewise, enable setting extension variables in block scopes via the debugger interface.
- While at it, refactor and unify some respective code in the debugger.
Sorry, this CL is large. I could try to split it up, but everything is rather entangled.
@mstarzinger: Please review the changes to contexts.
@yangguo: Please have a look at the debugger stuff.
R=littledan@chromium.org, mstarzinger@chromium.org, yangguo@chromium.org
BUG=v8:811,v8:2160
LOG=N
Review URL: https://codereview.chromium.org/1292753007
Cr-Commit-Position: refs/heads/master@{#30295}
Reason for revert:
This performance hack is no longer necessary.
Original issue's description:
> Group lexical context variables for faster look up.
>
> Currently, looking up a lexical context variable requires looking up
> the variable name and then checking its mode. This can be a bottleneck
> in Runtime_DeclareGlobals, even when no lexical context variables are
> declared.
>
> R=rossberg@chromium.org
> BUG=crbug:517778
> LOG=N
>
> Committed: https://crrev.com/a45ed17bb6aca02e940f13bbf456d660cccc86ae
> Cr-Commit-Position: refs/heads/master@{#30075}
TBR=rossberg@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=crbug:517778
Review URL: https://codereview.chromium.org/1290053002
Cr-Commit-Position: refs/heads/master@{#30145}
Currently, looking up a lexical context variable requires looking up
the variable name and then checking its mode. This can be a bottleneck
in Runtime_DeclareGlobals, even when no lexical context variables are
declared.
R=rossberg@chromium.org
BUG=crbug:517778
LOG=N
Review URL: https://codereview.chromium.org/1281883002
Cr-Commit-Position: refs/heads/master@{#30075}
Don't use different read/write slots for context globals, but
let them share the same slot, which reduces the number of
initial misses, and also saves some memory for large scripts.
R=yangguo@chromium.org
Review URL: https://codereview.chromium.org/1258213002
Cr-Commit-Position: refs/heads/master@{#29889}
While at it, remove the notion of INTERNAL variables.
@caitp: Took some parts from your CL, since I was blocked on the temp scope bug.
R=mstarzinger@chromium.org
BUG=512574
LOG=N
Review URL: https://codereview.chromium.org/1250513004
Cr-Commit-Position: refs/heads/master@{#29812}
Checking for native context is faster than checking for global object. Additionally it speeds up the case were it actually is the native context, while not slowing down the alternative case. The bootstrapper only needs to access the native context from the native context, so this avoids the expensive fallback.
BUG=
Review URL: https://codereview.chromium.org/1214903017
Cr-Commit-Position: refs/heads/master@{#29423}
When compiling on a laptop I like to concatenate the small test files.
This makes a big difference to compile times. These changes make that
easier.
R=ulan@chromium.org
BUG=
Review URL: https://codereview.chromium.org/1163803002
Cr-Commit-Position: refs/heads/master@{#28742}
... and the following two
"PPC: Resolve references to "this" the same way as normal variables"
"Remove Scope::scope_uses_this_ flag"
R=hablich@chromium.org
BUG=chromium:487289
LOG=N
Review URL: https://codereview.chromium.org/1134003003
Cr-Commit-Position: refs/heads/master@{#28395}
Make the parser handle references to "this" as unresolved variables, so the
same logic as for the rest of function parameters is used for the receiver.
Minor additions to the code generation handle copying the receiver to the
context, along with the rest of the function parameters.
Based on work by Adrian Perez de Castro <aperez@igalia.com>.
This is a reapplication of https://codereview.chromium.org/1130733003.
R=rossberg@chromium.org
BUG=v8:2700
LOG=N
Review URL: https://codereview.chromium.org/1136073002
Cr-Commit-Position: refs/heads/master@{#28340}
Reason for revert:
[Sheriff] Breaks jetstream benchmark with errors like this:
>>> Running suite: JetStream/bigfib.cpp
>>> Stdout (#1):
undefined:93: ReferenceError: this is not defined
this['Module'] = Module;
^
ReferenceError: this is not defined
at eval (eval at __run (runner.js:13:3), <anonymous>:93:3)
at eval (native)
at __run (runner.js:13:3)
at Object.runSimpleBenchmark (runner.js:44:31)
at runner.js:97:13
Original issue's description:
> Resolve references to "this" the same way as normal variables
>
> Make the parser handle references to "this" as unresolved variables, so the
> same logic as for the rest of function parameters is used for the receiver.
> Minor additions to the code generation handle copying the receiver to the
> context, along with the rest of the function parameters.
>
> Based on work by Adrian Perez de Castro <aperez@igalia.com>.
>
> BUG=v8:2700
> LOG=N
>
> Committed: https://crrev.com/06a792b7cc2db33ffce7244c044a9c05afbb6116
> Cr-Commit-Position: refs/heads/master@{#28263}
TBR=rossberg@chromium.org,arv@chromium.org,wingo@igalia.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:2700
Review URL: https://codereview.chromium.org/1129723003
Cr-Commit-Position: refs/heads/master@{#28283}
Make the parser handle references to "this" as unresolved variables, so the
same logic as for the rest of function parameters is used for the receiver.
Minor additions to the code generation handle copying the receiver to the
context, along with the rest of the function parameters.
Based on work by Adrian Perez de Castro <aperez@igalia.com>.
BUG=v8:2700
LOG=N
Review URL: https://codereview.chromium.org/1130733003
Cr-Commit-Position: refs/heads/master@{#28263}
Reason for revert:
nosnap failures
Original issue's description:
> Resolve references to "this" the same way as normal variables
>
> Make the parser handle references to "this" as unresolved variables, so the
> same logic as for the rest of function parameters is used for the receiver.
> Minor additions to the code generation handle copying the receiver to the
> context, along with the rest of the function parameters.
>
> Based on work by Adrian Perez de Castro <aperez@igalia.com>.
>
> BUG=
> LOG=N
>
> Committed: https://crrev.com/18619d355192e2699203d12d9ebb9caea107b693
> Cr-Commit-Position: refs/heads/master@{#28236}
TBR=rossberg@chromium.org,mstarzinger@chromium.org,dslomov@chromium.org,adamk@chromium.org,arv@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=
Review URL: https://codereview.chromium.org/1113133006
Cr-Commit-Position: refs/heads/master@{#28238}
Make the parser handle references to "this" as unresolved variables, so the
same logic as for the rest of function parameters is used for the receiver.
Minor additions to the code generation handle copying the receiver to the
context, along with the rest of the function parameters.
Based on work by Adrian Perez de Castro <aperez@igalia.com>.
BUG=
LOG=N
Review URL: https://codereview.chromium.org/1097283003
Cr-Commit-Position: refs/heads/master@{#28236}
The spec settled on ToBoolean instead of only using not undefined.
BUG=v8:3827
LOG=N
R=adamk
Review URL: https://codereview.chromium.org/1045113002
Cr-Commit-Position: refs/heads/master@{#27548}
This also adds a new VariableMode, IMPORT, which will be
used to do appropriate binding for Import-declared Variables.
Only named imports are handled for now. "import *" and default
import syntaxes have had their TODOs adjusted to match the new
code structure.
BUG=v8:1569
LOG=n
Review URL: https://codereview.chromium.org/948303004
Cr-Commit-Position: refs/heads/master@{#26895}
This gets Variable and VariableProxy out of the business of worrying about
Interfaces.
At the same time, get rid of the notion of "module variables". In ES6, variables
that refer to modules will be simply be CONST bindings to module namespace
objects.
The only change in logic here is one more early error:
duplicate export names are now rejected.
BUG=v8:1569
LOG=n
Review URL: https://codereview.chromium.org/918373002
Cr-Commit-Position: refs/heads/master@{#26708}
The spec ended up using Get(unscopables, propertyName) and
comparing the result to undefined instead of using Has.
BUG=v8:3632
LOG=Y
R=adamk, dslomov@chromium.org
Review URL: https://codereview.chromium.org/807893002
Cr-Commit-Position: refs/heads/master@{#25854}
This implements correct semantics for "extensible" top level lexical scope.
The entire lexical scope is represented at runtime by GlobalContextTable, reachable from native context and accumulating global contexts from every script loaded into the context.
When the new script starts executing, it does the following validation:
- checks the GlobalContextTable and global object (non-configurable own) properties against the set of declarations it introduces and reports potential conflicts.
- invalidates the conflicting PropertyCells on global object, so that any code depending on them will miss/deopt causing any contextual lookups to be reexecuted under the new bindings
- adds the lexical bindings it introduces to the GlobalContextTable
Loads and stores for contextual lookups are modified so that they check the GlobalContextTable before looking up properties on global object, thus implementing the shadowing of global object properties by lexical declarations.
R=adamk@chromium.org, rossberg@chromium.org
Review URL: https://codereview.chromium.org/705663004
Cr-Commit-Position: refs/heads/master@{#25220}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25220 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
