MIPS: Lazily save double registers for HCallRuntime instructions within Hydrogen code stubs.

src/mips/lithium-mips.cc

Index: src/mips/lithium-mips.cc
diff --git a/src/mips/lithium-mips.cc b/src/mips/lithium-mips.cc
index 8a349120eb6458dd51579896282dd99fbebcf9a1..e32a44dde7cf72b63f50ca954e358faa0b854715 100644
--- a/src/mips/lithium-mips.cc
+++ b/src/mips/lithium-mips.cc
@@ -867,6 +867,10 @@ void LChunkBuilder::VisitInstruction(HInstruction* current) {
   LInstruction* instr = current->CompileToLithium(this);
 
   if (instr != NULL) {
+    // Associate the hydrogen instruction first, since we may need it for
+    // the ClobbersRegisters() or ClobbersDoubleRegisters() calls below.
+    instr->set_hydrogen_value(current);
+
 #if DEBUG
     // Make sure that the lithium instruction has either no fixed register
     // constraints in temps or the result OR no uses that are only used at
@@ -903,7 +907,6 @@ void LChunkBuilder::VisitInstruction(HInstruction* current) {
     if (FLAG_stress_environments && !instr->HasEnvironment()) {
       instr = AssignEnvironment(instr);
     }
-    instr->set_hydrogen_value(current);
     chunk_->AddInstruction(instr, current_block_);
   }
   current_instruction_ = old_current;