Refactor load forwarding pass to use a Place abstraction.

runtime/vm/il_printer.cc

Index: runtime/vm/il_printer.cc
diff --git a/runtime/vm/il_printer.cc b/runtime/vm/il_printer.cc
index f40e2bec686661f7247286961f9223c55d0e9ef2..cdddcd7c01aa0216b2d2b54e7e3052057cccb169 100644
--- a/runtime/vm/il_printer.cc
+++ b/runtime/vm/il_printer.cc
@@ -37,6 +37,7 @@ void FlowGraphPrinter::PrintGraph(const char* phase, FlowGraph* flow_graph) {
   FlowGraphPrinter printer(*flow_graph);
   printer.PrintBlocks();
   OS::Print("*** END CFG\n");
+  fflush(stdout);
 }
 
 
@@ -131,8 +132,6 @@ const char* CompileType::ToCString() const {
 }
 
 
-
-
 static void PrintICData(BufferFormatter* f, const ICData& ic_data) {
   f->Print(" IC[%"Pd": ", ic_data.NumberOfChecks());
   Function& target = Function::Handle();
@@ -171,6 +170,14 @@ static void PrintUse(BufferFormatter* f, const Definition& definition) {
 }
 
 
+const char* Instruction::ToCString() const {
+  char buffer[1024];
+  BufferFormatter f(buffer, sizeof(buffer));
+  PrintTo(&f);
+  return Isolate::Current()->current_zone()->MakeCopyOfString(buffer);
+}
+
+
 void Instruction::PrintTo(BufferFormatter* f) const {
   if (GetDeoptId() != Isolate::kNoDeoptId) {
     f->Print("%s:%"Pd"(", DebugName(), GetDeoptId());