Initial support for polymorphic inlining.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 481 matching lines @@
     Value* prev = previous_use();
     prev->set_next_use(next);
     if (next != NULL) next->set_previous_use(prev);
   }
 
   set_previous_use(NULL);
   set_next_use(NULL);
 }
 
 
+// True if the definition has a single input use and is used only in
+// environments at the same instruction as that input use.
 bool Definition::HasOnlyUse(Value* use) const {
-  return (input_use_list() == use) &&
-     (use->next_use() == NULL) &&
-     ((env_use_list() == NULL) ||
-      ((env_use_list()->instruction() == use->instruction()) &&
-       (env_use_list()->next_use() == NULL)));
+  if ((input_use_list() != use) || (use->next_use() != NULL)) return false;
+
+  Instruction* target = use->instruction();
+  for (Value::Iterator it(env_use_list()); !it.Done(); it.Advance()) {
+    if (it.Current()->instruction() != target) return false;
+  }
+  return true;
 }
 
 
 void Definition::ReplaceUsesWith(Definition* other) {
   ASSERT(other != NULL);
   ASSERT(this != other);
 
   Value* current = NULL;
   Value* next = input_use_list();
   if (next != NULL) {
@@ skipping 969 matching lines @@
   UNREACHABLE();
   return NULL;
 }
 
 
 void PhiInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   UNREACHABLE();
 }
 
 
+LocationSummary* RedefinitionInstr::MakeLocationSummary() const {
+  UNREACHABLE();
+  return NULL;
+}
+
+
+void RedefinitionInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  UNREACHABLE();
+}
+
+
 LocationSummary* ParameterInstr::MakeLocationSummary() const {
   UNREACHABLE();
   return NULL;
 }
 
 
 void ParameterInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   UNREACHABLE();
 }
 
@@ skipping 909 matching lines @@
     default:
       UNREACHABLE();
   }
   return kPowRuntimeEntry;
 }
 
 
 #undef __
 
 }  // namespace dart