src/scopes.cc - Issue 883823002: Implement proper scoping for "this" in arrow functions

Unified Diff: src/scopes.cc

Issue 883823002: Implement proper scoping for "this" in arrow functions Base URL: https://chromium.googlesource.com/v8/v8.git@master

Patch Set: mjsunit/debug-scopes: Skip "this" the same as "arguments" Created 5 years, 10 months ago

Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.

Jump to:

View side-by-side diff with in-line comments

Download patch

Index: src/scopes.cc

diff --git a/src/scopes.cc b/src/scopes.cc

index 80bf82b6b60277627ece3d20b51e1f35da774d78..10bf867911551707ee36a78dcf5e7330c48758f5 100644

--- a/src/scopes.cc

+++ b/src/scopes.cc

@@ -31,7 +31,7 @@ VariableMap::~VariableMap() {}

Variable* VariableMap::Declare(Scope* scope, const AstRawString* name,

- VariableMode mode, bool is_valid_lhs,

+ VariableMode mode,

Variable::Kind kind,

InitializationFlag initialization_flag,

MaybeAssignedFlag maybe_assigned_flag,

@@ -45,7 +45,7 @@ Variable* VariableMap::Declare(Scope* scope, const AstRawString* name,

// The variable has not been declared yet -> insert it.

DCHECK(p->key == name);

p->value = new (zone())

- Variable(scope, name, mode, is_valid_lhs, kind, initialization_flag,

+ Variable(scope, name, mode, kind, initialization_flag,

maybe_assigned_flag, interface);

}

return reinterpret_cast<Variable*>(p->value);

@@ -137,7 +137,6 @@ Scope::Scope(Isolate* isolate, Zone* zone, Scope* inner_scope,

Variable* variable = variables_.Declare(this,

catch_variable_name,

VAR,

- true, // Valid left-hand side.

Variable::NORMAL,

kCreatedInitialized);

AllocateHeapSlot(variable);

@@ -161,7 +160,6 @@ void Scope::SetDefaults(ScopeType scope_type,

scope_uses_arguments_ = false;

scope_uses_super_property_ = false;

scope_uses_super_constructor_call_ = false;

- scope_uses_this_ = false;

asm_module_ = false;

asm_function_ = outer_scope != NULL && outer_scope->asm_module_;

// Inherit the strict mode from the parent scope.

@@ -169,7 +167,6 @@ void Scope::SetDefaults(ScopeType scope_type,

outer_scope_calls_sloppy_eval_ = false;

inner_scope_calls_eval_ = false;

inner_scope_uses_arguments_ = false;

- inner_scope_uses_this_ = false;

inner_scope_uses_super_property_ = false;

inner_scope_uses_super_constructor_call_ = false;

force_eager_compilation_ = false;

@@ -310,19 +307,14 @@ void Scope::Initialize() {

// instead load them directly from the stack. Currently, the only

// such parameter is 'this' which is passed on the stack when

// invoking scripts

- if (is_declaration_scope()) {

+ if (has_this_declaration()) {

Variable* var =

variables_.Declare(this,

ast_value_factory_->this_string(),

VAR,

- false,

Variable::THIS,

kCreatedInitialized);

- var->AllocateTo(Variable::PARAMETER, -1);

receiver_ = var;

- } else {

- DCHECK(outer_scope() != NULL);

- receiver_ = outer_scope()->receiver();

}

if (is_function_scope()) {

@@ -332,7 +324,6 @@ void Scope::Initialize() {

variables_.Declare(this,

ast_value_factory_->arguments_string(),

VAR,

- true,

Variable::ARGUMENTS,

kCreatedInitialized);

}

@@ -370,7 +361,6 @@ Scope* Scope::FinalizeBlockScope() {

if (uses_super_property()) outer_scope_->RecordSuperPropertyUsage();

if (uses_super_constructor_call())

outer_scope_->RecordSuperConstructorCallUsage();

- if (uses_this()) outer_scope_->RecordThisUsage();

return NULL;

}

@@ -410,7 +400,7 @@ Variable* Scope::LookupLocal(const AstRawString* name) {

maybe_assigned_flag = kMaybeAssigned;

}

- Variable* var = variables_.Declare(this, name, mode, true, Variable::NORMAL,

+ Variable* var = variables_.Declare(this, name, mode, Variable::NORMAL,

init_flag, maybe_assigned_flag);

var->AllocateTo(location, index);

return var;

@@ -426,9 +416,8 @@ Variable* Scope::LookupFunctionVar(const AstRawString* name,

VariableMode mode;

int index = scope_info_->FunctionContextSlotIndex(*(name->string()), &mode);

if (index < 0) return NULL;

- Variable* var = new(zone()) Variable(

- this, name, mode, true /* is valid LHS */,

- Variable::NORMAL, kCreatedInitialized);

+ Variable* var = new(zone()) Variable(this, name,

+ mode, Variable::NORMAL, kCreatedInitialized);

VariableProxy* proxy = factory->NewVariableProxy(var);

VariableDeclaration* declaration = factory->NewVariableDeclaration(

proxy, mode, this, RelocInfo::kNoPosition);

@@ -456,7 +445,7 @@ Variable* Scope::DeclareParameter(const AstRawString* name, VariableMode mode,

bool is_rest) {

DCHECK(!already_resolved());

DCHECK(is_function_scope());

- Variable* var = variables_.Declare(this, name, mode, true, Variable::NORMAL,

+ Variable* var = variables_.Declare(this, name, mode, Variable::NORMAL,

kCreatedInitialized);

if (is_rest) {

DCHECK_NULL(rest_parameter_);

@@ -478,7 +467,7 @@ Variable* Scope::DeclareLocal(const AstRawString* name, VariableMode mode,

// explicitly, and TEMPORARY variables are allocated via NewTemporary().

DCHECK(IsDeclaredVariableMode(mode));

++num_var_or_const_;

- return variables_.Declare(this, name, mode, true, Variable::NORMAL, init_flag,

+ return variables_.Declare(this, name, mode, Variable::NORMAL, init_flag,

maybe_assigned_flag, interface);

}

@@ -488,7 +477,6 @@ Variable* Scope::DeclareDynamicGlobal(const AstRawString* name) {

return variables_.Declare(this,

name,

DYNAMIC_GLOBAL,

- true,

Variable::NORMAL,

kCreatedInitialized);

}

@@ -511,7 +499,6 @@ Variable* Scope::NewInternal(const AstRawString* name) {

Variable* var = new(zone()) Variable(this,

name,

INTERNAL,

- false,

Variable::NORMAL,

kCreatedInitialized);

internals_.Add(var, zone());

@@ -524,7 +511,6 @@ Variable* Scope::NewTemporary(const AstRawString* name) {

Variable* var = new(zone()) Variable(this,

name,

TEMPORARY,

- true,

Variable::NORMAL,

kCreatedInitialized);

temps_.Add(var, zone());

@@ -900,7 +886,6 @@ void Scope::Print(int n) {

Indent(n1, "// scope uses 'super' property\n");

if (scope_uses_super_constructor_call_)

Indent(n1, "// scope uses 'super' constructor\n");

- if (scope_uses_this_) Indent(n1, "// scope uses 'this'\n");

if (inner_scope_uses_arguments_) {

Indent(n1, "// inner scope uses 'arguments'\n");

}

@@ -909,7 +894,6 @@ void Scope::Print(int n) {

if (inner_scope_uses_super_constructor_call_) {

Indent(n1, "// inner scope uses 'super' constructor\n");

}

- if (inner_scope_uses_this_) Indent(n1, "// inner scope uses 'this'\n");

if (outer_scope_calls_sloppy_eval_) {

Indent(n1, "// outer scope calls 'eval' in sloppy context\n");

}

@@ -975,7 +959,6 @@ Variable* Scope::NonLocal(const AstRawString* name, VariableMode mode) {

var = map->Declare(NULL,

name,

mode,

- true,

Variable::NORMAL,

init_flag);

// Allocate it by giving it a dynamic lookup.

@@ -1189,9 +1172,6 @@ void Scope::PropagateScopeInfo(bool outer_scope_calls_sloppy_eval ) {

inner->inner_scope_uses_super_constructor_call_) {

inner_scope_uses_super_constructor_call_ = true;

}

- if (inner->scope_uses_this_ || inner->inner_scope_uses_this_) {

- inner_scope_uses_this_ = true;

- }

}

if (inner->force_eager_compilation_) {

force_eager_compilation_ = true;

@@ -1220,7 +1200,7 @@ bool Scope::MustAllocate(Variable* var) {

if (scope_calls_eval_ || inner_scope_calls_eval_) var->set_maybe_assigned();

}

// Global variables do not need to be allocated.

- return !var->IsGlobalObjectProperty() && var->is_used();

+ return var->is_this() || (var->is_used() && !var->IsGlobalObjectProperty());

}

@@ -1311,18 +1291,33 @@ void Scope::AllocateParameterLocals() {

// Force context allocation of the parameter.

var->ForceContextAllocation();

}

+ AllocateParameter(var, i);

+ }

- if (MustAllocate(var)) {

- if (MustAllocateInContext(var)) {

- DCHECK(var->IsUnallocated() || var->IsContextSlot());

- if (var->IsUnallocated()) {

- AllocateHeapSlot(var);

- }

- } else {

- DCHECK(var->IsUnallocated() || var->IsParameter());

- if (var->IsUnallocated()) {

- var->AllocateTo(Variable::PARAMETER, i);

- }

+void Scope::AllocateReceiver() {

+ DCHECK_EQ(receiver()->scope(), this);

+ if (has_forced_context_allocation()) {

+ // Force context allocation of the receiver.

+ receiver()->ForceContextAllocation();

+ }

+ AllocateParameter(receiver(), -1);

+void Scope::AllocateParameter(Variable* var, int index) {

+ if (MustAllocate(var)) {

+ if (MustAllocateInContext(var)) {

+ DCHECK(var->IsUnallocated() || var->IsContextSlot());

+ if (var->IsUnallocated()) {

+ AllocateHeapSlot(var);

+ }

+ } else {

+ DCHECK(var->IsUnallocated() || var->IsParameter());

+ if (var->IsUnallocated()) {

+ var->AllocateTo(Variable::PARAMETER, index);

}

@@ -1395,6 +1390,7 @@ void Scope::AllocateVariablesRecursively() {

// Allocate variables for this scope.

// Parameters must be allocated first, if any.

+ if (has_this_declaration()) AllocateReceiver();

if (is_function_scope()) AllocateParameterLocals();

AllocateNonParameterLocals();

« src/scopes.h ('K') | « src/scopes.h ('k') | src/variables.h » ('j') | no next file with comments »