Support for global var shortcuts in script contexts.

src/arm/full-codegen-arm.cc

Index: src/arm/full-codegen-arm.cc
diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index 059ffe656f6b2d10c5ee71996d472fa65c0a54b3..65abe076ee75feca6d5ed4e05bb0d84bb386df84 100644
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -351,7 +351,7 @@ void FullCodeGenerator::Generate() {
         VariableDeclaration* function = scope()->function();
         DCHECK(function->proxy()->var()->mode() == CONST ||
                function->proxy()->var()->mode() == CONST_LEGACY);
-        DCHECK(function->proxy()->var()->location() != Variable::UNALLOCATED);
+        DCHECK(!function->proxy()->var()->IsUnallocatedOrGlobalSlot());
         VisitVariableDeclaration(function);
       }
       VisitDeclarations(scope()->declarations());
@@ -875,7 +875,8 @@ void FullCodeGenerator::VisitVariableDeclaration(
   Variable* variable = proxy->var();
   bool hole_init = mode == LET || mode == CONST || mode == CONST_LEGACY;
   switch (variable->location()) {
-    case Variable::UNALLOCATED:
+    case VariableLocation::GLOBAL:
+    case VariableLocation::UNALLOCATED:
       globals_->Add(variable->name(), zone());
       globals_->Add(variable->binding_needs_init()
                         ? isolate()->factory()->the_hole_value()
@@ -883,8 +884,8 @@ void FullCodeGenerator::VisitVariableDeclaration(
                     zone());
       break;
 
-    case Variable::PARAMETER:
-    case Variable::LOCAL:
+    case VariableLocation::PARAMETER:
+    case VariableLocation::LOCAL:
       if (hole_init) {
         Comment cmnt(masm_, "[ VariableDeclaration");
         __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
@@ -892,7 +893,7 @@ void FullCodeGenerator::VisitVariableDeclaration(
       }
       break;
 
-    case Variable::CONTEXT:
+    case VariableLocation::CONTEXT:
       if (hole_init) {
         Comment cmnt(masm_, "[ VariableDeclaration");
         EmitDebugCheckDeclarationContext(variable);
@@ -903,7 +904,7 @@ void FullCodeGenerator::VisitVariableDeclaration(
       }
       break;
 
-    case Variable::LOOKUP: {
+    case VariableLocation::LOOKUP: {
       Comment cmnt(masm_, "[ VariableDeclaration");
       __ mov(r2, Operand(variable->name()));
       // Declaration nodes are always introduced in one of four modes.
@@ -934,7 +935,8 @@ void FullCodeGenerator::VisitFunctionDeclaration(
   VariableProxy* proxy = declaration->proxy();
   Variable* variable = proxy->var();
   switch (variable->location()) {
-    case Variable::UNALLOCATED: {
+    case VariableLocation::GLOBAL:
+    case VariableLocation::UNALLOCATED: {
       globals_->Add(variable->name(), zone());
       Handle<SharedFunctionInfo> function =
           Compiler::GetSharedFunctionInfo(declaration->fun(), script(), info_);
@@ -944,15 +946,15 @@ void FullCodeGenerator::VisitFunctionDeclaration(
       break;
     }
 
-    case Variable::PARAMETER:
-    case Variable::LOCAL: {
+    case VariableLocation::PARAMETER:
+    case VariableLocation::LOCAL: {
       Comment cmnt(masm_, "[ FunctionDeclaration");
       VisitForAccumulatorValue(declaration->fun());
       __ str(result_register(), StackOperand(variable));
       break;
     }
 
-    case Variable::CONTEXT: {
+    case VariableLocation::CONTEXT: {
       Comment cmnt(masm_, "[ FunctionDeclaration");
       EmitDebugCheckDeclarationContext(variable);
       VisitForAccumulatorValue(declaration->fun());
@@ -971,7 +973,7 @@ void FullCodeGenerator::VisitFunctionDeclaration(
       break;
     }
 
-    case Variable::LOOKUP: {
+    case VariableLocation::LOOKUP: {
       Comment cmnt(masm_, "[ FunctionDeclaration");
       __ mov(r2, Operand(variable->name()));
       __ mov(r1, Operand(Smi::FromInt(NONE)));
@@ -989,20 +991,21 @@ void FullCodeGenerator::VisitImportDeclaration(ImportDeclaration* declaration) {
   VariableProxy* proxy = declaration->proxy();
   Variable* variable = proxy->var();
   switch (variable->location()) {
-    case Variable::UNALLOCATED:
+    case VariableLocation::GLOBAL:
+    case VariableLocation::UNALLOCATED:
       // TODO(rossberg)
       break;
 
-    case Variable::CONTEXT: {
+    case VariableLocation::CONTEXT: {
       Comment cmnt(masm_, "[ ImportDeclaration");
       EmitDebugCheckDeclarationContext(variable);
       // TODO(rossberg)
       break;
     }
 
-    case Variable::PARAMETER:
-    case Variable::LOCAL:
-    case Variable::LOOKUP:
+    case VariableLocation::PARAMETER:
+    case VariableLocation::LOCAL:
+    case VariableLocation::LOOKUP:
       UNREACHABLE();
   }
 }
@@ -1499,7 +1502,8 @@ void FullCodeGenerator::EmitVariableLoad(VariableProxy* proxy) {
   // Three cases: global variables, lookup variables, and all other types of
   // variables.
   switch (var->location()) {
-    case Variable::UNALLOCATED: {
+    case VariableLocation::GLOBAL:
+    case VariableLocation::UNALLOCATED: {
       Comment cmnt(masm_, "[ Global variable");
       __ ldr(LoadDescriptor::ReceiverRegister(), GlobalObjectOperand());
       __ mov(LoadDescriptor::NameRegister(), Operand(var->name()));
@@ -1510,9 +1514,9 @@ void FullCodeGenerator::EmitVariableLoad(VariableProxy* proxy) {
       break;
     }
 
-    case Variable::PARAMETER:
-    case Variable::LOCAL:
-    case Variable::CONTEXT: {
+    case VariableLocation::PARAMETER:
+    case VariableLocation::LOCAL:
+    case VariableLocation::CONTEXT: {
       Comment cmnt(masm_, var->IsContextSlot() ? "[ Context variable"
                                                : "[ Stack variable");
       if (var->binding_needs_init()) {
@@ -1581,7 +1585,7 @@ void FullCodeGenerator::EmitVariableLoad(VariableProxy* proxy) {
       break;
     }
 
-    case Variable::LOOKUP: {
+    case VariableLocation::LOOKUP: {
       Comment cmnt(masm_, "[ Lookup variable");
       Label done, slow;
       // Generate code for loading from variables potentially shadowed
@@ -2737,7 +2741,7 @@ void FullCodeGenerator::EmitStoreToStackLocalOrContextSlot(
 
 void FullCodeGenerator::EmitVariableAssignment(Variable* var, Token::Value op,
                                                FeedbackVectorICSlot slot) {
-  if (var->IsUnallocated()) {
+  if (var->IsUnallocatedOrGlobalSlot()) {
     // Global var, const, or let.
     __ mov(StoreDescriptor::NameRegister(), Operand(var->name()));
     __ ldr(StoreDescriptor::ReceiverRegister(), GlobalObjectOperand());
@@ -4797,7 +4801,7 @@ void FullCodeGenerator::VisitUnaryOperation(UnaryOperation* expr) {
         // "delete this" is allowed.
         bool is_this = var->HasThisName(isolate());
         DCHECK(is_sloppy(language_mode()) || is_this);
-        if (var->IsUnallocated()) {
+        if (var->IsUnallocatedOrGlobalSlot()) {
           __ ldr(r2, GlobalObjectOperand());
           __ mov(r1, Operand(var->name()));
           __ mov(r0, Operand(Smi::FromInt(SLOPPY)));
@@ -5154,7 +5158,7 @@ void FullCodeGenerator::VisitForTypeofValue(Expression* expr) {
   DCHECK(!context()->IsEffect());
   DCHECK(!context()->IsTest());
   VariableProxy* proxy = expr->AsVariableProxy();
-  if (proxy != NULL && proxy->var()->IsUnallocated()) {
+  if (proxy != NULL && proxy->var()->IsUnallocatedOrGlobalSlot()) {
     Comment cmnt(masm_, "[ Global variable");
     __ ldr(LoadDescriptor::ReceiverRegister(), GlobalObjectOperand());
     __ mov(LoadDescriptor::NameRegister(), Operand(proxy->name()));