Revert "Merge arguments branch to bleeding merge."

src/ia32/full-codegen-ia32.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 200 matching lines @@
       __ push(edi);
     } else {
       __ push(Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
     }
     // Receiver is just before the parameters on the caller's stack.
     int offset = scope()->num_parameters() * kPointerSize;
     __ lea(edx,
            Operand(ebp, StandardFrameConstants::kCallerSPOffset + offset));
     __ push(edx);
     __ SafePush(Immediate(Smi::FromInt(scope()->num_parameters())));
-    // Arguments to ArgumentsAccessStub and/or New...:
+    // Arguments to ArgumentsAccessStub:
     //   function, receiver address, parameter count.
     // The stub will rewrite receiver and parameter count if the previous
     // stack frame was an arguments adapter frame.
-    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);
+    ArgumentsAccessStub stub(
+        is_strict_mode() ? ArgumentsAccessStub::NEW_STRICT
+                         : ArgumentsAccessStub::NEW_NON_STRICT);
     __ CallStub(&stub);
 
+    Variable* arguments_shadow = scope()->arguments_shadow();
+    if (arguments_shadow != NULL) {
+      __ mov(ecx, eax);  // Duplicate result.
+      Move(arguments_shadow->AsSlot(), ecx, ebx, edx);
+    }
     Move(arguments->AsSlot(), eax, ebx, edx);
   }
 
   if (FLAG_trace) {
     __ CallRuntime(Runtime::kTraceEnter, 0);
   }
 
   // Visit the declarations and body unless there is an illegal
   // redeclaration.
   if (scope()->HasIllegalRedeclaration()) {
@@ skipping 122 matching lines @@
   MemOperand slot_operand = codegen()->EmitSlotSearch(slot, result_register());
   // Memory operands can be pushed directly.
   __ push(slot_operand);
 }
 
 
 void FullCodeGenerator::TestContext::Plug(Slot* slot) const {
   // For simplicity we always test the accumulator register.
   codegen()->Move(result_register(), slot);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Heap::RootListIndex index) const {
   UNREACHABLE();  // Not used on IA32.
 }
 
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(
     Heap::RootListIndex index) const {
@@ skipping 53 matching lines @@
     }
   } else if (lit->IsSmi()) {
     if (Smi::cast(*lit)->value() == 0) {
       if (false_label_ != fall_through_) __ jmp(false_label_);
     } else {
       if (true_label_ != fall_through_) __ jmp(true_label_);
     }
   } else {
     // For simplicity we always test the accumulator register.
     __ mov(result_register(), lit);
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
 
 void FullCodeGenerator::EffectContext::DropAndPlug(int count,
                                                    Register reg) const {
   ASSERT(count > 0);
   __ Drop(count);
 }
 
@@ skipping 15 matching lines @@
 }
 
 
 void FullCodeGenerator::TestContext::DropAndPlug(int count,
                                                  Register reg) const {
   ASSERT(count > 0);
   // For simplicity we always test the accumulator register.
   __ Drop(count);
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
 void FullCodeGenerator::EffectContext::Plug(Label* materialize_true,
                                             Label* materialize_false) const {
   ASSERT(materialize_true == materialize_false);
   __ bind(materialize_true);
 }
 
 
@@ skipping 56 matching lines @@
                                           true_label_,
                                           false_label_);
   if (flag) {
     if (true_label_ != fall_through_) __ jmp(true_label_);
   } else {
     if (false_label_ != fall_through_) __ jmp(false_label_);
   }
 }
 
 
-void FullCodeGenerator::DoTest(Label* if_true,
+void FullCodeGenerator::DoTest(Expression* condition,
+                               Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   ToBooleanStub stub;
   __ push(result_register());
   __ CallStub(&stub);
   __ test(eax, Operand(eax));
   // The stub returns nonzero for true.
   Split(not_zero, if_true, if_false, fall_through);
 }
 
@@ skipping 626 matching lines @@
           EmitCallIC(ic, RelocInfo::CODE_TARGET, GetPropertyId(property));
           __ jmp(done);
         }
       }
     }
   }
 }
 
 
 void FullCodeGenerator::EmitVariableLoad(Variable* var) {
-  // Three cases: non-this global variables, lookup slots, and all other
-  // types of slots.
+  // 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.
   Slot* slot = var->AsSlot();
-  ASSERT((var->is_global() && !var->is_this()) == (slot == NULL));
+  Property* property = var->AsProperty();
 
-  if (slot == NULL) {
+  if (var->is_global() && !var->is_this()) {
     Comment cmnt(masm_, "Global variable");
     // Use inline caching. Variable name is passed in ecx and the global
     // object on the stack.
     __ mov(eax, GlobalObjectOperand());
     __ mov(ecx, var->name());
     Handle<Code> ic = isolate()->builtins()->LoadIC_Initialize();
     EmitCallIC(ic, RelocInfo::CODE_TARGET_CONTEXT, AstNode::kNoNumber);
     context()->Plug(eax);
 
-  } else if (slot->type() == Slot::LOOKUP) {
+  } else if (slot != NULL && slot->type() == Slot::LOOKUP) {
     Label done, slow;
 
     // Generate code for loading from variables potentially shadowed
     // by eval-introduced variables.
     EmitDynamicLoadFromSlotFastCase(slot, NOT_INSIDE_TYPEOF, &slow, &done);
 
     __ bind(&slow);
     Comment cmnt(masm_, "Lookup slot");
     __ push(esi);  // Context.
     __ push(Immediate(var->name()));
     __ CallRuntime(Runtime::kLoadContextSlot, 2);
     __ bind(&done);
 
     context()->Plug(eax);
 
-  } else {
+  } else if (slot != NULL) {
     Comment cmnt(masm_, (slot->type() == Slot::CONTEXT)
                             ? "Context slot"
                             : "Stack slot");
     if (var->mode() == Variable::CONST) {
       // Constants may be the hole value if they have not been initialized.
       // Unhole them.
       Label done;
       MemOperand slot_operand = EmitSlotSearch(slot, eax);
       __ mov(eax, slot_operand);
       __ cmp(eax, isolate()->factory()->the_hole_value());
       __ j(not_equal, &done, Label::kNear);
       __ mov(eax, isolate()->factory()->undefined_value());
       __ bind(&done);
       context()->Plug(eax);
     } 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.
+    MemOperand object_loc = EmitSlotSearch(object_slot, eax);
+    __ mov(edx, object_loc);
+
+    // 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.
+    __ SafeSet(eax, Immediate(key_literal->handle()));
+
+    // Do a keyed property load.
+    Handle<Code> ic = isolate()->builtins()->KeyedLoadIC_Initialize();
+    EmitCallIC(ic, RelocInfo::CODE_TARGET, GetPropertyId(property));
+
+    // Drop key and object left on the stack by IC.
+    context()->Plug(eax);
   }
 }
 
 
 void FullCodeGenerator::VisitRegExpLiteral(RegExpLiteral* expr) {
   Comment cmnt(masm_, "[ RegExpLiteral");
   Label materialized;
   // Registers will be used as follows:
   // edi = JS function.
   // ecx = literals array.
@@ skipping 212 matching lines @@
 void FullCodeGenerator::VisitAssignment(Assignment* expr) {
   Comment cmnt(masm_, "[ Assignment");
   // Invalid left-hand sides are rewritten to have a 'throw ReferenceError'
   // on the left-hand side.
   if (!expr->target()->IsValidLeftHandSide()) {
     VisitForEffect(expr->target());
     return;
   }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
-  // slot.
+  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* property = expr->target()->AsProperty();
   if (property != NULL) {
     assign_type = (property->key()->IsPropertyName())
         ? NAMED_PROPERTY
         : KEYED_PROPERTY;
   }
 
   // Evaluate LHS expression.
   switch (assign_type) {
     case VARIABLE:
       // Nothing to do here.
       break;
     case NAMED_PROPERTY:
       if (expr->is_compound()) {
         // We need the receiver both on the stack and in the accumulator.
         VisitForAccumulatorValue(property->obj());
         __ push(result_register());
       } else {
         VisitForStackValue(property->obj());
       }
       break;
     case KEYED_PROPERTY: {
       if (expr->is_compound()) {
-        VisitForStackValue(property->obj());
-        VisitForAccumulatorValue(property->key());
+        if (property->is_arguments_access()) {
+          VariableProxy* obj_proxy = property->obj()->AsVariableProxy();
+          MemOperand slot_operand =
+              EmitSlotSearch(obj_proxy->var()->AsSlot(), ecx);
+          __ push(slot_operand);
+          __ SafeSet(eax, Immediate(property->key()->AsLiteral()->handle()));
+        } else {
+          VisitForStackValue(property->obj());
+          VisitForAccumulatorValue(property->key());
+        }
         __ mov(edx, Operand(esp, 0));
         __ push(eax);
       } else {
-        VisitForStackValue(property->obj());
-        VisitForStackValue(property->key());
+        if (property->is_arguments_access()) {
+          VariableProxy* obj_proxy = property->obj()->AsVariableProxy();
+          MemOperand slot_operand =
+              EmitSlotSearch(obj_proxy->var()->AsSlot(), ecx);
+          __ push(slot_operand);
+          __ SafePush(Immediate(property->key()->AsLiteral()->handle()));
+        } else {
+          VisitForStackValue(property->obj());
+          VisitForStackValue(property->key());
+        }
       }
       break;
     }
   }
 
   // For compound assignments we need another deoptimization point after the
   // variable/property load.
   if (expr->is_compound()) {
     { AccumulatorValueContext context(this);
       switch (assign_type) {
@@ skipping 183 matching lines @@
 
 void FullCodeGenerator::EmitAssignment(Expression* expr, int bailout_ast_id) {
   // Invalid left-hand sides are rewritten to have a 'throw
   // ReferenceError' on the left-hand side.
   if (!expr->IsValidLeftHandSide()) {
     VisitForEffect(expr);
     return;
   }
 
   // Left-hand side can only be a property, a global or a (parameter or local)
-  // slot.
+  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* prop = expr->AsProperty();
   if (prop != NULL) {
     assign_type = (prop->key()->IsPropertyName())
         ? NAMED_PROPERTY
         : KEYED_PROPERTY;
   }
 
   switch (assign_type) {
@@ skipping 39 matching lines @@
       break;
     }
   }
   PrepareForBailoutForId(bailout_ast_id, TOS_REG);
   context()->Plug(eax);
 }
 
 
 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);
 
   if (var->is_global()) {
     ASSERT(!var->is_this());
     // Assignment to a global variable.  Use inline caching for the
     // assignment.  Right-hand-side value is passed in eax, variable name in
     // ecx, and the global object on the stack.
     __ mov(ecx, var->name());
     __ mov(edx, GlobalObjectOperand());
@@ skipping 1932 matching lines @@
   SetSourcePosition(expr->position());
 
   // Invalid left-hand sides are rewritten to have a 'throw ReferenceError'
   // as the left-hand side.
   if (!expr->expression()->IsValidLeftHandSide()) {
     VisitForEffect(expr->expression());
     return;
   }
 
   // Expression can only be a property, a global or a (parameter or local)
-  // slot.
+  // slot. Variables with rewrite to .arguments are treated as KEYED_PROPERTY.
   enum LhsKind { VARIABLE, NAMED_PROPERTY, KEYED_PROPERTY };
   LhsKind assign_type = VARIABLE;
   Property* prop = expr->expression()->AsProperty();
   // In case of a property we use the uninitialized expression context
   // of the key to detect a named property.
   if (prop != NULL) {
     assign_type =
         (prop->key()->IsPropertyName()) ? NAMED_PROPERTY : KEYED_PROPERTY;
   }
 
   // Evaluate expression and get value.
   if (assign_type == VARIABLE) {
     ASSERT(expr->expression()->AsVariableProxy()->var() != NULL);
     AccumulatorValueContext context(this);
     EmitVariableLoad(expr->expression()->AsVariableProxy()->var());
   } else {
     // Reserve space for result of postfix operation.
     if (expr->is_postfix() && !context()->IsEffect()) {
       __ push(Immediate(Smi::FromInt(0)));
     }
     if (assign_type == NAMED_PROPERTY) {
       // Put the object both on the stack and in the accumulator.
       VisitForAccumulatorValue(prop->obj());
       __ push(eax);
       EmitNamedPropertyLoad(prop);
     } else {
-      VisitForStackValue(prop->obj());
-      VisitForAccumulatorValue(prop->key());
+      if (prop->is_arguments_access()) {
+        VariableProxy* obj_proxy = prop->obj()->AsVariableProxy();
+        MemOperand slot_operand =
+            EmitSlotSearch(obj_proxy->var()->AsSlot(), ecx);
+        __ push(slot_operand);
+        __ SafeSet(eax, Immediate(prop->key()->AsLiteral()->handle()));
+      } else {
+        VisitForStackValue(prop->obj());
+        VisitForAccumulatorValue(prop->key());
+      }
       __ mov(edx, Operand(esp, 0));
       __ push(eax);
       EmitKeyedPropertyLoad(prop);
     }
   }
 
   // We need a second deoptimization point after loading the value
   // in case evaluating the property load my have a side effect.
   if (assign_type == VARIABLE) {
     PrepareForBailout(expr->expression(), TOS_REG);
@@ skipping 491 matching lines @@
   // And return.
   __ ret(0);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32