So far free variables references in eval code are not statically
resolved. For example in
function foo() { var x = 1; eval("y = x"); }
the variable x will get mode DYNAMIC and y will get mode DYNAMIC_GLOBAL,
i.e. free variable references trigger dynamic lookups with a fast case
handling for global variables.
The CL introduces static resolution of free variables references in eval
code. If possible variable references are resolved to bindings belonging to
outer scopes of the eval call site.
This is achieved by deserializing the outer scope chain using
Scope::DeserializeScopeChain prior to parsing the eval code similar to lazy
parsing of functions. The existing code for variable resolution is used,
however resolution starts at the first outer unresolved scope instead of
always starting at the root of the scope tree.
This is a prerequisite for statically checking validity of assignments in
the extended code as specified by the current ES.next draft which will be
introduced by a subsequent CL. More specifically section 11.13 of revision 4
of the ES.next draft 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.
TEST=existing tests in mjsunit
Review URL: http://codereview.chromium.org/8508052
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9999 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
After introduction of with scopes we have enough static information to omit
context allocation in the case that a variable is accessed from a nested block
or catch scope of the same function. Only variables accessed from the inside of
a nested function or with scope are forced to be allocated in the context.
This essentially reverts
http://code.google.com/p/v8/source/detail?r=9281 .
which in turn reverted an earlier change.
Review URL: http://codereview.chromium.org/8431001
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9872 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
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
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
Eliminate the LocalType enum in favor of a pair of functions, one for var
and const declarations and one for parameters. Move the responsibility for
adding a parameter variable to the Scope's internal data structure into the
Scope and out of the parser.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8091 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
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
Revision 6635 added an assert on IA32 that there were no 'const' parameters.
This assert could be hit at compile time because we compiled the unreachable
body of functions with illegal redeclarations, which are thrown at runtime.
Review URL: http://codereview.chromium.org/6286144
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6659 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This is svn r6415 with a bugfix.
The bug was that we can have scopes with 0 heap slots (functions with
such scopes do not need a local context) and scopes with at least
Context::MIN_CONTEXT_SLOTS. The code generator only allocated a local
context if there were strictly more than Context::MIN_CONTEXT_SLOTS.
Before the change to with/arguments, it was impossible to actually get
a function scope with exactly Context::MIN_CONTEXT_SLOTS because every
such scope included a heap-allocated arguments (and arguments shadow)
slot.
Review URL: http://codereview.chromium.org/6248014
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6426 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Before, we conservatively marked every variable in a scope as used if the
scope contained 'with'. Instead, just mark the variables occurring in the
body of the with. This avoids marking 'arguments' as used whenever 'with'
occurs, which incurs an extra performance penalty (a use of arguments is
seen as an instruction to redirect all parameter accesses to the arguments
object).
Review URL: http://codereview.chromium.org/6357007
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6415 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
