Author: [email protected]
Date: Wed May 13 09:27:40 2009
New Revision: 1937
Modified:
branches/bleeding_edge/src/scopes.cc
branches/bleeding_edge/src/scopes.h
Log:
Avoid linear search for non-locals in the scope code
when resolving variables inside with and eval scopes.
Review URL: http://codereview.chromium.org/114024
Modified: branches/bleeding_edge/src/scopes.cc
==============================================================================
--- branches/bleeding_edge/src/scopes.cc (original)
+++ branches/bleeding_edge/src/scopes.cc Wed May 13 09:27:40 2009
@@ -112,7 +112,9 @@
locals_(false),
temps_(0),
params_(0),
- nonlocals_(0),
+ dynamics_(false),
+ dynamics_local_(false),
+ dynamics_global_(false),
unresolved_(0),
decls_(0) {
}
@@ -126,7 +128,6 @@
locals_(),
temps_(4),
params_(4),
- nonlocals_(4),
unresolved_(16),
decls_(4),
receiver_(NULL),
@@ -405,6 +406,14 @@
}
+static void PrintMap(PrettyPrinter* printer, int indent, LocalsMap* map) {
+ for (LocalsMap::Entry* p = map->Start(); p != NULL; p = map->Next(p)) {
+ Variable* var = reinterpret_cast<Variable*>(p->value);
+ PrintVar(printer, indent, var);
+ }
+}
+
+
void Scope::Print(int n) {
int n0 = (n > 0 ? n : 0);
int n1 = n0 + 2; // indentation
@@ -465,14 +474,12 @@
}
Indent(n1, "// local vars\n");
- for (LocalsMap::Entry* p = locals_.Start(); p != NULL; p =
locals_.Next(p)) {
- Variable* var = reinterpret_cast<Variable*>(p->value);
- PrintVar(&printer, n1, var);
- }
+ PrintMap(&printer, n1, &locals_);
- Indent(n1, "// nonlocal vars\n");
- for (int i = 0; i < nonlocals_.length(); i++)
- PrintVar(&printer, n1, nonlocals_[i]);
+ Indent(n1, "// dynamic vars\n");
+ PrintMap(&printer, n1, &dynamics_);
+ PrintMap(&printer, n1, &dynamics_local_);
+ PrintMap(&printer, n1, &dynamics_global_);
// Print inner scopes (disable by providing negative n).
if (n >= 0) {
@@ -490,20 +497,28 @@
Variable* Scope::NonLocal(Handle<String> name, Variable::Mode mode) {
// Space optimization: reuse existing non-local with the same name
// and mode.
- for (int i = 0; i < nonlocals_.length(); i++) {
- Variable* var = nonlocals_[i];
- if (var->name().is_identical_to(name) && var->mode() == mode) {
- return var;
- }
+ LocalsMap* map = NULL;
+ switch (mode) {
+ case Variable::DYNAMIC:
+ map = &dynamics_;
+ break;
+ case Variable::DYNAMIC_LOCAL:
+ map = &dynamics_local_;
+ break;
+ case Variable::DYNAMIC_GLOBAL:
+ map = &dynamics_global_;
+ break;
+ default:
+ UNREACHABLE();
+ break;
+ }
+ Variable* var = map->Lookup(name);
+ if (var == NULL) {
+ // Declare a new non-local.
+ var = map->Declare(NULL, name, mode, true, false);
+ // Allocate it by giving it a dynamic lookup.
+ var->rewrite_ = new Slot(var, Slot::LOOKUP, -1);
}
-
- // Otherwise create a new non-local and add it to the list.
- Variable* var = new Variable(NULL, name, mode, true, false);
- nonlocals_.Add(var);
-
- // Allocate it by giving it a dynamic lookup.
- var->rewrite_ = new Slot(var, Slot::LOOKUP, -1);
-
return var;
}
@@ -617,14 +632,6 @@
ASSERT(global_scope != NULL);
var = new Variable(global_scope, proxy->name(),
Variable::DYNAMIC, true, false);
- // Ideally we simply rewrite these variables into property
- // accesses. Unfortunately, we cannot do this here at the
- // moment because then we can't differentiate between
- // global variable ('x') and global property ('this.x') access.
- // If 'x' doesn't exist, the former leads to an error, while the
- // latter returns undefined. Sigh...
- // var->rewrite_ = new Property(new Literal(env_->global()),
- // new Literal(proxy->name()));
} else if (scope_inside_with_) {
// If we are inside a with statement we give up and look up
Modified: branches/bleeding_edge/src/scopes.h
==============================================================================
--- branches/bleeding_edge/src/scopes.h (original)
+++ branches/bleeding_edge/src/scopes.h Wed May 13 09:27:40 2009
@@ -278,7 +278,9 @@
// parameter list in source order
ZoneList<Variable*> params_;
// variables that must be looked up dynamically
- ZoneList<Variable*> nonlocals_;
+ LocalsMap dynamics_;
+ LocalsMap dynamics_local_;
+ LocalsMap dynamics_global_;
// unresolved variables referred to from this scope
ZoneList<VariableProxy*> unresolved_;
// declarations
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