Merge ConstantInstr -> UnboxDouble to UnboxedConstant. Reduces register usage and allows for variou…

runtime/vm/flow_graph_compiler_mips.cc

Index: runtime/vm/flow_graph_compiler_mips.cc
===================================================================
--- runtime/vm/flow_graph_compiler_mips.cc	(revision 35656)
+++ runtime/vm/flow_graph_compiler_mips.cc	(working copy)
@@ -1684,13 +1684,17 @@
     UNIMPLEMENTED();
   } else {
     ASSERT(source.IsConstant());
+    const Object& constant = source.constant();
     if (destination.IsRegister()) {
-      const Object& constant = source.constant();
       __ LoadObject(destination.reg(), constant);
+    } else if (destination.IsFpuRegister()) {
+      __ LoadObject(TMP, constant);
+      __ LoadDFromOffset(destination.fpu_reg(), TMP,
+          Double::value_offset() - kHeapObjectTag);
     } else {
       ASSERT(destination.IsStackSlot());
       const intptr_t dest_offset = destination.ToStackSlotOffset();
-      __ LoadObject(TMP, source.constant());
+      __ LoadObject(TMP, constant);
       __ StoreToOffset(TMP, FP, dest_offset);
     }
   }