MIPS: Add monomorphic CompareNilICs and Crankshaft support

Port r14407 (cae6596b)

BUG=

Review URL: https://codereview.chromium.org/13840006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14427 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/mips/code-stubs-mips.cc

@@ -97,6 +97,19 @@ void TransitionElementsKindStub::InitializeInterfaceDescriptor(
 }
 
 
+void CompareNilICStub::InitializeInterfaceDescriptor(
+    Isolate* isolate,
+    CodeStubInterfaceDescriptor* descriptor) {
+  static Register registers[] = { a0 };
+  descriptor->register_param_count_ = 1;
+  descriptor->register_params_ = registers;
+  descriptor->deoptimization_handler_ =
+      FUNCTION_ADDR(CompareNilIC_Miss);
+  descriptor->miss_handler_ =
+      ExternalReference(IC_Utility(IC::kCompareNilIC_Miss), isolate);
+}
+
+
 static void InitializeArrayConstructorDescriptor(Isolate* isolate,
     CodeStubInterfaceDescriptor* descriptor) {
   // register state

src/mips/full-codegen-mips.cc

@@ -4452,26 +4452,21 @@ void FullCodeGenerator::EmitLiteralCompareNil(CompareOperation* expr,
 
   VisitForAccumulatorValue(sub_expr);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Heap::RootListIndex nil_value = nil == kNullValue ?
-      Heap::kNullValueRootIndex :
-      Heap::kUndefinedValueRootIndex;
+  EqualityKind kind = expr->op() == Token::EQ_STRICT
+      ? kStrictEquality : kNonStrictEquality;
   __ mov(a0, result_register());
-  __ LoadRoot(a1, nil_value);
-  if (expr->op() == Token::EQ_STRICT) {
+  if (kind == kStrictEquality) {
+    Heap::RootListIndex nil_value = nil == kNullValue ?
+        Heap::kNullValueRootIndex :
+        Heap::kUndefinedValueRootIndex;
+    __ LoadRoot(a1, nil_value);
     Split(eq, a0, Operand(a1), if_true, if_false, fall_through);
   } else {
-    Heap::RootListIndex other_nil_value = nil == kNullValue ?
-        Heap::kUndefinedValueRootIndex :
-        Heap::kNullValueRootIndex;
-    __ Branch(if_true, eq, a0, Operand(a1));
-    __ LoadRoot(a1, other_nil_value);
-    __ Branch(if_true, eq, a0, Operand(a1));
-    __ JumpIfSmi(a0, if_false);
-    // It can be an undetectable object.
-    __ lw(a1, FieldMemOperand(a0, HeapObject::kMapOffset));
-    __ lbu(a1, FieldMemOperand(a1, Map::kBitFieldOffset));
-    __ And(a1, a1, Operand(1 << Map::kIsUndetectable));
-    Split(ne, a1, Operand(zero_reg), if_true, if_false, fall_through);
+    Handle<Code> ic = CompareNilICStub::GetUninitialized(isolate(),
+                                                         kNonStrictEquality,
+                                                         nil);
+    CallIC(ic, RelocInfo::CODE_TARGET, expr->CompareOperationFeedbackId());
+    Split(ne, v0, Operand(zero_reg), if_true, if_false, fall_through);
   }
   context()->Plug(if_true, if_false);
 }