[heap] User safer root set accessor when possible.

src/x87/macro-assembler-x87.cc

Index: src/x87/macro-assembler-x87.cc
diff --git a/src/x87/macro-assembler-x87.cc b/src/x87/macro-assembler-x87.cc
index 1fab3aa7a3bcb754757f48f1ac389e2a4a05457b..d888f9fa63809ff68e32622cfab2c06caa983b65 100644
--- a/src/x87/macro-assembler-x87.cc
+++ b/src/x87/macro-assembler-x87.cc
@@ -66,8 +66,7 @@ void MacroAssembler::Store(Register src, const Operand& dst, Representation r) {
 
 void MacroAssembler::LoadRoot(Register destination, Heap::RootListIndex index) {
   if (isolate()->heap()->RootCanBeTreatedAsConstant(index)) {
-    Handle<Object> value(&isolate()->heap()->roots_array_start()[index]);
-    mov(destination, value);
+    mov(destination, isolate()->heap()->root_handle(index));
     return;
   }
   ExternalReference roots_array_start =
@@ -105,16 +104,14 @@ void MacroAssembler::CompareRoot(Register with,
 
 void MacroAssembler::CompareRoot(Register with, Heap::RootListIndex index) {
   DCHECK(isolate()->heap()->RootCanBeTreatedAsConstant(index));
-  Handle<Object> value(&isolate()->heap()->roots_array_start()[index]);
-  cmp(with, value);
+  cmp(with, isolate()->heap()->root_handle(index));
 }
 
 
 void MacroAssembler::CompareRoot(const Operand& with,
                                  Heap::RootListIndex index) {
   DCHECK(isolate()->heap()->RootCanBeTreatedAsConstant(index));
-  Handle<Object> value(&isolate()->heap()->roots_array_start()[index]);
-  cmp(with, value);
+  cmp(with, isolate()->heap()->root_handle(index));
 }