Use a uniform way to emit code for all instructions.

runtime/vm/intermediate_language_mips.cc

Index: runtime/vm/intermediate_language_mips.cc
diff --git a/runtime/vm/intermediate_language_mips.cc b/runtime/vm/intermediate_language_mips.cc
index f9e270bc4b0c228fed5e0b0d99a1316be55e0f19..139e72685221cbc437fdceac87c8dd6b160cdd46 100644
--- a/runtime/vm/intermediate_language_mips.cc
+++ b/runtime/vm/intermediate_language_mips.cc
@@ -2380,8 +2380,11 @@ void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
 
 
 LocationSummary* BranchInstr::MakeLocationSummary() const {
-  UNREACHABLE();
-  return NULL;
+  LocationSummary* summary = comparison()->locs();
+  // Share the location summary with the comparison.  Branches don't produce
+  // a result.
+  summary->set_out(Location::NoLocation());
+  return summary;
 }
 
 
@@ -2608,14 +2611,6 @@ LocationSummary* GotoInstr::MakeLocationSummary() const {
 
 void GotoInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   __ TraceSimMsg("GotoInstr");
-  if (!compiler->is_optimizing()) {
-    // Add deoptimization descriptor for deoptimizing instructions that may
-    // be inserted before this instruction.
-    compiler->AddCurrentDescriptor(PcDescriptors::kDeopt,
-                                   GetDeoptId(),
-                                   0);  // No token position.
-  }
-
   if (HasParallelMove()) {
     compiler->parallel_move_resolver()->EmitNativeCode(parallel_move());
   }