MIPS: This CL simplifies var / const by ensuring the behavior is consistent in itself, and with reg…

src/mips/full-codegen-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
@@ skipping 838 matching lines @@
       // 'undefined') because we may have a (legal) redeclaration and we
       // must not destroy the current value.
       if (hole_init) {
         __ LoadRoot(a0, Heap::kTheHoleValueRootIndex);
         __ Push(cp, a2, a1, a0);
       } else {
         ASSERT(Smi::FromInt(0) == 0);
         __ mov(a0, zero_reg);  // Smi::FromInt(0) indicates no initial value.
         __ Push(cp, a2, a1, a0);
       }
-      __ CallRuntime(Runtime::kDeclareContextSlot, 4);
+      __ CallRuntime(Runtime::kDeclareLookupSlot, 4);
       break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitFunctionDeclaration(
     FunctionDeclaration* declaration) {
   VariableProxy* proxy = declaration->proxy();
   Variable* variable = proxy->var();
@@ skipping 35 matching lines @@
       break;
     }
 
     case Variable::LOOKUP: {
       Comment cmnt(masm_, "[ FunctionDeclaration");
       __ li(a2, Operand(variable->name()));
       __ li(a1, Operand(Smi::FromInt(NONE)));
       __ Push(cp, a2, a1);
       // Push initial value for function declaration.
       VisitForStackValue(declaration->fun());
-      __ CallRuntime(Runtime::kDeclareContextSlot, 4);
+      __ CallRuntime(Runtime::kDeclareLookupSlot, 4);
       break;
     }
   }
 }
 
 
 void FullCodeGenerator::VisitModuleDeclaration(ModuleDeclaration* declaration) {
   Variable* variable = declaration->proxy()->var();
   ASSERT(variable->location() == Variable::CONTEXT);
   ASSERT(variable->interface()->IsFrozen());
@@ skipping 1519 matching lines @@
   if (var->IsContextSlot()) {
     // RecordWrite may destroy all its register arguments.
     __ Move(a3, result_register());
     int offset = Context::SlotOffset(var->index());
     __ RecordWriteContextSlot(
         a1, offset, a3, a2, kRAHasBeenSaved, kDontSaveFPRegs);
   }
 }
 
 
-void FullCodeGenerator::EmitCallStoreContextSlot(
-    Handle<String> name, StrictMode strict_mode) {
-  __ li(a1, Operand(name));
-  __ li(a0, Operand(Smi::FromInt(strict_mode)));
-  __ Push(v0, cp, a1, a0);  // Value, context, name, strict mode.
-  __ CallRuntime(Runtime::kStoreContextSlot, 4);
-}
-
-
 void FullCodeGenerator::EmitVariableAssignment(Variable* var, Token::Value op) {
   if (var->IsUnallocated()) {
     // Global var, const, or let.
     __ mov(StoreIC::ValueRegister(), result_register());
     __ li(StoreIC::NameRegister(), Operand(var->name()));
     __ lw(StoreIC::ReceiverRegister(), GlobalObjectOperand());
     CallStoreIC();
 
   } else if (op == Token::INIT_CONST_LEGACY) {
     // Const initializers need a write barrier.
     ASSERT(!var->IsParameter());  // No const parameters.
     if (var->IsLookupSlot()) {
       __ li(a0, Operand(var->name()));
       __ Push(v0, cp, a0);  // Context and name.
-      __ CallRuntime(Runtime::kInitializeConstContextSlot, 3);
+      __ CallRuntime(Runtime::kInitializeLegacyConstLookupSlot, 3);
     } else {
       ASSERT(var->IsStackAllocated() || var->IsContextSlot());
       Label skip;
       MemOperand location = VarOperand(var, a1);
       __ lw(a2, location);
       __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
       __ Branch(&skip, ne, a2, Operand(at));
       EmitStoreToStackLocalOrContextSlot(var, location);
       __ bind(&skip);
     }
 
   } else if (var->mode() == LET && op != Token::INIT_LET) {
     // Non-initializing assignment to let variable needs a write barrier.
-    if (var->IsLookupSlot()) {
-      EmitCallStoreContextSlot(var->name(), strict_mode());
-    } else {
-      ASSERT(var->IsStackAllocated() || var->IsContextSlot());
-      Label assign;
-      MemOperand location = VarOperand(var, a1);
-      __ lw(a3, location);
-      __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
-      __ Branch(&assign, ne, a3, Operand(t0));
-      __ li(a3, Operand(var->name()));
-      __ push(a3);
-      __ CallRuntime(Runtime::kThrowReferenceError, 1);
-      // Perform the assignment.
-      __ bind(&assign);
-      EmitStoreToStackLocalOrContextSlot(var, location);
-    }
+    ASSERT(!var->IsLookupSlot());
+    ASSERT(var->IsStackAllocated() || var->IsContextSlot());
+    Label assign;
+    MemOperand location = VarOperand(var, a1);
+    __ lw(a3, location);
+    __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
+    __ Branch(&assign, ne, a3, Operand(t0));
+    __ li(a3, Operand(var->name()));
+    __ push(a3);
+    __ CallRuntime(Runtime::kThrowReferenceError, 1);
+    // Perform the assignment.
+    __ bind(&assign);
+    EmitStoreToStackLocalOrContextSlot(var, location);
 
   } else if (!var->is_const_mode() || op == Token::INIT_CONST) {
-    // Assignment to var or initializing assignment to let/const
-    // in harmony mode.
     if (var->IsLookupSlot()) {
-      EmitCallStoreContextSlot(var->name(), strict_mode());
+      ASSERT(op == Token::ASSIGN || op == Token::INIT_VAR ||
+             op == Token::ASSIGN_ADD);
+      // Assignment to var.
+      __ li(a1, Operand(var->name()));
+      __ li(a0, Operand(Smi::FromInt(strict_mode())));
+      __ Push(v0, cp, a1, a0);  // Value, context, name, strict mode.
+      __ CallRuntime(Runtime::kStoreLookupSlot, 4);
     } else {
+      // Assignment to var or initializing assignment to let/const in harmony
+      // mode.
       ASSERT((var->IsStackAllocated() || var->IsContextSlot()));
       MemOperand location = VarOperand(var, a1);
       if (generate_debug_code_ && op == Token::INIT_LET) {
         // Check for an uninitialized let binding.
         __ lw(a2, location);
         __ LoadRoot(t0, Heap::kTheHoleValueRootIndex);
         __ Check(eq, kLetBindingReInitialization, a2, Operand(t0));
       }
       EmitStoreToStackLocalOrContextSlot(var, location);
     }
@@ skipping 2337 matching lines @@
       Assembler::target_address_at(pc_immediate_load_address)) ==
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS