Introduce "optimized_out" oddball marker for compilers.

src/crankshaft/hydrogen.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/crankshaft/hydrogen.h"
 
 #include <sstream>
 
 #include "src/allocation-site-scopes.h"
 #include "src/ast/ast-numbering.h"
@@ skipping 672 matching lines @@
 
 HConstant* HGraph::GetConstantMinus1() {
   return GetConstant(&constant_minus1_, -1);
 }
 
 
 HConstant* HGraph::GetConstantBool(bool value) {
   return value ? GetConstantTrue() : GetConstantFalse();
 }
 
-#define DEFINE_GET_CONSTANT(Name, name, type, htype, boolean_value,         \
-                            undetectable)                                   \
-  HConstant* HGraph::GetConstant##Name() {                                  \
-    if (!constant_##name##_.is_set()) {                                     \
-      HConstant* constant = new (zone()) HConstant(                         \
-          Unique<Object>::CreateImmovable(                                  \
-              isolate()->factory()->name##_value()),                        \
-          Unique<Map>::CreateImmovable(isolate()->factory()->type##_map()), \
-          false, Representation::Tagged(), htype, true, boolean_value,      \
-          undetectable, ODDBALL_TYPE);                                      \
-      constant->InsertAfter(entry_block()->first());                        \
-      constant_##name##_.set(constant);                                     \
-    }                                                                       \
-    return ReinsertConstantIfNecessary(constant_##name##_.get());           \
+#define DEFINE_GET_CONSTANT(Name, name, constant, type, htype, boolean_value, \
+                            undetectable)                                     \
+  HConstant* HGraph::GetConstant##Name() {                                    \
+    if (!constant_##name##_.is_set()) {                                       \
+      HConstant* constant = new (zone()) HConstant(                           \
+          Unique<Object>::CreateImmovable(isolate()->factory()->constant()),  \
+          Unique<Map>::CreateImmovable(isolate()->factory()->type##_map()),   \
+          false, Representation::Tagged(), htype, true, boolean_value,        \
+          undetectable, ODDBALL_TYPE);                                        \
+      constant->InsertAfter(entry_block()->first());                          \
+      constant_##name##_.set(constant);                                       \
+    }                                                                         \
+    return ReinsertConstantIfNecessary(constant_##name##_.get());             \
   }
 
-DEFINE_GET_CONSTANT(Undefined, undefined, undefined, HType::Undefined(), false,
-                    true)
-DEFINE_GET_CONSTANT(True, true, boolean, HType::Boolean(), true, false)
-DEFINE_GET_CONSTANT(False, false, boolean, HType::Boolean(), false, false)
-DEFINE_GET_CONSTANT(Hole, the_hole, the_hole, HType::None(), false, false)
-DEFINE_GET_CONSTANT(Null, null, null, HType::Null(), false, true)
+DEFINE_GET_CONSTANT(Undefined, undefined, undefined_value, undefined,
+                    HType::Undefined(), false, true)
+DEFINE_GET_CONSTANT(True, true, true_value, boolean, HType::Boolean(), true,
+                    false)
+DEFINE_GET_CONSTANT(False, false, false_value, boolean, HType::Boolean(), false,
+                    false)
+DEFINE_GET_CONSTANT(Hole, the_hole, the_hole_value, the_hole, HType::None(),
+                    false, false)
+DEFINE_GET_CONSTANT(Null, null, null_value, null, HType::Null(), false, true)
+DEFINE_GET_CONSTANT(OptimizedOut, optimized_out, optimized_out, optimized_out,
+                    HType::None(), false, false)
 
 #undef DEFINE_GET_CONSTANT
 
 #define DEFINE_IS_CONSTANT(Name, name)                                         \
 bool HGraph::IsConstant##Name(HConstant* constant) {                           \
   return constant_##name##_.is_set() && constant == constant_##name##_.get();  \
 }
 DEFINE_IS_CONSTANT(Undefined, undefined)
 DEFINE_IS_CONSTANT(0, 0)
 DEFINE_IS_CONSTANT(1, 1)
@@ skipping 12770 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8