- Reduce the number of Isolate::Current() calls.

runtime/vm/flow_graph_compiler.cc

Index: runtime/vm/flow_graph_compiler.cc
===================================================================
--- runtime/vm/flow_graph_compiler.cc	(revision 36483)
+++ runtime/vm/flow_graph_compiler.cc	(working copy)
@@ -83,7 +83,8 @@
 FlowGraphCompiler::FlowGraphCompiler(Assembler* assembler,
                                      FlowGraph* flow_graph,
                                      bool is_optimizing)
-    : assembler_(assembler),
+    : isolate_(Isolate::Current()),
+      assembler_(assembler),
       parsed_function_(flow_graph->parsed_function()),
       flow_graph_(*flow_graph),
       block_order_(*flow_graph->CodegenBlockOrder(is_optimizing)),
@@ -395,7 +396,7 @@
     move_instr->AddMove(dest, src);
     // Update safepoint bitmap to indicate that the target location
     // now contains a pointer.
-    instr->locs()->stack_bitmap()->Set(dest_index, true);
+    instr->locs()->SetStackBit(dest_index);
   }
   parallel_move_resolver()->EmitNativeCode(move_instr);
 }
@@ -976,7 +977,7 @@
 void FlowGraphCompiler::AllocateRegistersLocally(Instruction* instr) {
   ASSERT(!is_optimizing());
 
-  instr->InitializeLocationSummary(false);  // Not optimizing.
+  instr->InitializeLocationSummary(isolate(), false);  // Not optimizing.
   LocationSummary* locs = instr->locs();
 
   bool blocked_registers[kNumberOfCpuRegisters];