Fix exception for assignment to uninitialised const

src/arm64/full-codegen-arm64.cc

 // Copyright 2013 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_ARM64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
@@ skipping 2429 matching lines @@
     MemOperand location = VarOperand(var, x1);
     __ Ldr(x10, location);
     __ JumpIfNotRoot(x10, Heap::kTheHoleValueRootIndex, &assign);
     __ Mov(x10, Operand(var->name()));
     __ Push(x10);
     __ CallRuntime(Runtime::kThrowReferenceError, 1);
     // Perform the assignment.
     __ Bind(&assign);
     EmitStoreToStackLocalOrContextSlot(var, location);
 
+  } else if (var->mode() == CONST && op != Token::INIT_CONST) {

[Dmitry Lomov (no reviews), 2015/03/04 17:57:35]

Looks like the case at line 2488 anymore should be CONST_LEGACY and not
INIT_CONST_LEGACY. Just remove IsSignallingAssignmentToConst altoghether.

+    // Assignment to const variable needs a write barrier.
+    DCHECK(!var->IsLookupSlot());
+    DCHECK(var->IsStackAllocated() || var->IsContextSlot());
+    Label const_error;
+    MemOperand location = VarOperand(var, x1);
+    __ Ldr(x10, location);
+    __ JumpIfNotRoot(x10, Heap::kTheHoleValueRootIndex, &const_error);
+    __ Mov(x10, Operand(var->name()));
+    __ Push(x10);
+    __ CallRuntime(Runtime::kThrowReferenceError, 1);
+    __ Bind(&const_error);
+    __ CallRuntime(Runtime::kThrowConstAssignError, 0);
+
   } else if (!var->is_const_mode() || op == Token::INIT_CONST) {
     if (var->IsLookupSlot()) {
       // Assignment to var.
       __ Mov(x11, Operand(var->name()));
       __ Mov(x10, Smi::FromInt(language_mode()));
       // jssp[0]  : mode.
       // jssp[8]  : name.
       // jssp[16] : context.
       // jssp[24] : value.
       __ Push(x0, cp, x11, x10);
@@ skipping 3020 matching lines @@
   return previous_;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64