Merge arguments branch to bleeding edge (second try).

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 31d2b929fd403f615f97fac252b3d6a93acc545e..ff8506d1f86176417f06ce3645d2fc64f2650ee5 100644
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -230,17 +230,17 @@ void FullCodeGenerator::Generate(CompilationInfo* info) {
     //   function, receiver address, parameter count.
     // The stub will rewrite receiever and parameter count if the previous
     // stack frame was an arguments adapter frame.
-    ArgumentsAccessStub stub(
-        is_strict_mode() ? ArgumentsAccessStub::NEW_STRICT
-                         : ArgumentsAccessStub::NEW_NON_STRICT);
+    ArgumentsAccessStub::Type type;
+    if (is_strict_mode()) {
+      type = ArgumentsAccessStub::NEW_STRICT;
+    } else if (function()->has_duplicate_parameters()) {
+      type = ArgumentsAccessStub::NEW_NON_STRICT_SLOW;
+    } else {
+      type = ArgumentsAccessStub::NEW_NON_STRICT_FAST;
+    }
+    ArgumentsAccessStub stub(type);
     __ CallStub(&stub);
 
-    Variable* arguments_shadow = scope()->arguments_shadow();
-    if (arguments_shadow != NULL) {
-      // Duplicate the value; move-to-slot operation might clobber registers.
-      __ mov(r3, r0);
-      Move(arguments_shadow->AsSlot(), r3, r1, r2);
-    }
     Move(arguments->AsSlot(), r0, r1, r2);
   }
 
@@ -1256,13 +1256,12 @@ void FullCodeGenerator::EmitDynamicLoadFromSlotFastCase(
 
 
 void FullCodeGenerator::EmitVariableLoad(Variable* var) {
-  // Four cases: non-this global variables, lookup slots, all other
-  // types of slots, and parameters that rewrite to explicit property
-  // accesses on the arguments object.
+  // Three cases: non-this global variables, lookup slots, and all other
+  // types of slots.
   Slot* slot = var->AsSlot();
-  Property* property = var->AsProperty();
+  ASSERT((var->is_global() && !var->is_this()) == (slot == NULL));
 
-  if (var->is_global() && !var->is_this()) {
+  if (slot == NULL) {
     Comment cmnt(masm_, "Global variable");
     // Use inline caching. Variable name is passed in r2 and the global
     // object (receiver) in r0.
@@ -1272,7 +1271,7 @@ void FullCodeGenerator::EmitVariableLoad(Variable* var) {
     EmitCallIC(ic, RelocInfo::CODE_TARGET_CONTEXT, AstNode::kNoNumber);
     context()->Plug(r0);
 
-  } else if (slot != NULL && slot->type() == Slot::LOOKUP) {
+  } else if (slot->type() == Slot::LOOKUP) {
     Label done, slow;
 
     // Generate code for loading from variables potentially shadowed
@@ -1288,7 +1287,7 @@ void FullCodeGenerator::EmitVariableLoad(Variable* var) {
 
     context()->Plug(r0);
 
-  } else if (slot != NULL) {
+  } else {
     Comment cmnt(masm_, (slot->type() == Slot::CONTEXT)
                             ? "Context slot"
                             : "Stack slot");
@@ -1304,32 +1303,6 @@ void FullCodeGenerator::EmitVariableLoad(Variable* var) {
     } else {
       context()->Plug(slot);
     }
-  } else {
-    Comment cmnt(masm_, "Rewritten parameter");
-    ASSERT_NOT_NULL(property);
-    // Rewritten parameter accesses are of the form "slot[literal]".
-
-    // Assert that the object is in a slot.
-    Variable* object_var = property->obj()->AsVariableProxy()->AsVariable();
-    ASSERT_NOT_NULL(object_var);
-    Slot* object_slot = object_var->AsSlot();
-    ASSERT_NOT_NULL(object_slot);
-
-    // Load the object.
-    Move(r1, object_slot);
-
-    // Assert that the key is a smi.
-    Literal* key_literal = property->key()->AsLiteral();
-    ASSERT_NOT_NULL(key_literal);
-    ASSERT(key_literal->handle()->IsSmi());
-
-    // Load the key.
-    __ mov(r0, Operand(key_literal->handle()));
-
-    // Call keyed load IC. It has arguments key and receiver in r0 and r1.
-    Handle<Code> ic = isolate()->builtins()->KeyedLoadIC_Initialize();
-    EmitCallIC(ic, RelocInfo::CODE_TARGET, GetPropertyId(property));
-    context()->Plug(r0);
   }
 }
 
@@ -1570,7 +1543,7 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
   }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
-  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
+  // slot.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* property = expr->target()->AsProperty();
@@ -1596,27 +1569,13 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
       break;
     case KEYED_PROPERTY:
       if (expr->is_compound()) {
-        if (property->is_arguments_access()) {
-          VariableProxy* obj_proxy = property->obj()->AsVariableProxy();
-          __ ldr(r0, EmitSlotSearch(obj_proxy->var()->AsSlot(), r0));
-          __ push(r0);
-          __ mov(r0, Operand(property->key()->AsLiteral()->handle()));
-        } else {
-          VisitForStackValue(property->obj());
-          VisitForAccumulatorValue(property->key());
-        }
+        VisitForStackValue(property->obj());
+        VisitForAccumulatorValue(property->key());
         __ ldr(r1, MemOperand(sp, 0));
         __ push(r0);
       } else {
-        if (property->is_arguments_access()) {
-          VariableProxy* obj_proxy = property->obj()->AsVariableProxy();
-          __ ldr(r1, EmitSlotSearch(obj_proxy->var()->AsSlot(), r0));
-          __ mov(r0, Operand(property->key()->AsLiteral()->handle()));
-          __ Push(r1, r0);
-        } else {
-          VisitForStackValue(property->obj());
-          VisitForStackValue(property->key());
-        }
+        VisitForStackValue(property->obj());
+        VisitForStackValue(property->key());
       }
       break;
   }
@@ -1823,7 +1782,7 @@ void FullCodeGenerator::EmitAssignment(Expression* expr, int bailout_ast_id) {
   }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
-  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
+  // slot.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* prop = expr->AsProperty();
@@ -1854,20 +1813,10 @@ void FullCodeGenerator::EmitAssignment(Expression* expr, int bailout_ast_id) {
     }
     case KEYED_PROPERTY: {
       __ push(r0);  // Preserve value.
-      if (prop->is_synthetic()) {
-        ASSERT(prop->obj()->AsVariableProxy() != NULL);
-        ASSERT(prop->key()->AsLiteral() != NULL);
-        { AccumulatorValueContext for_object(this);
-          EmitVariableLoad(prop->obj()->AsVariableProxy()->var());
-        }
-        __ mov(r2, r0);
-        __ mov(r1, Operand(prop->key()->AsLiteral()->handle()));
-      } else {
-        VisitForStackValue(prop->obj());
-        VisitForAccumulatorValue(prop->key());
-        __ mov(r1, r0);
-        __ pop(r2);
-      }
+      VisitForStackValue(prop->obj());
+      VisitForAccumulatorValue(prop->key());
+      __ mov(r1, r0);
+      __ pop(r2);
       __ pop(r0);  // Restore value.
       Handle<Code> ic = is_strict_mode()
           ? isolate()->builtins()->KeyedStoreIC_Initialize_Strict()
@@ -1883,8 +1832,6 @@ void FullCodeGenerator::EmitAssignment(Expression* expr, int bailout_ast_id) {
 
 void FullCodeGenerator::EmitVariableAssignment(Variable* var,
                                                Token::Value op) {
-  // Left-hand sides that rewrite to explicit property accesses do not reach
-  // here.
   ASSERT(var != NULL);
   ASSERT(var->is_global() || var->AsSlot() != NULL);
 
@@ -3824,7 +3771,7 @@ void FullCodeGenerator::VisitCountOperation(CountOperation* expr) {
   }
 
   // Expression can only be a property, a global or a (parameter or local)
-  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
+  // slot.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* prop = expr->expression()->AsProperty();
@@ -3852,15 +3799,8 @@ void FullCodeGenerator::VisitCountOperation(CountOperation* expr) {
       __ push(r0);
       EmitNamedPropertyLoad(prop);
     } else {
-      if (prop->is_arguments_access()) {
-        VariableProxy* obj_proxy = prop->obj()->AsVariableProxy();
-        __ ldr(r0, EmitSlotSearch(obj_proxy->var()->AsSlot(), r0));
-        __ push(r0);
-        __ mov(r0, Operand(prop->key()->AsLiteral()->handle()));
-      } else {
-        VisitForStackValue(prop->obj());
-        VisitForAccumulatorValue(prop->key());
-      }
+      VisitForStackValue(prop->obj());
+      VisitForAccumulatorValue(prop->key());
       __ ldr(r1, MemOperand(sp, 0));
       __ push(r0);
       EmitKeyedPropertyLoad(prop);