Fix bug in ParallelMoveResolver::EmitSwap: implement swaps of FPU spill slots.

runtime/vm/intermediate_language_x64.cc

Index: runtime/vm/intermediate_language_x64.cc
diff --git a/runtime/vm/intermediate_language_x64.cc b/runtime/vm/intermediate_language_x64.cc
index 3edf1edbcecb324315018930e85ed7b75c52aa68..a13034474da6675a27c22cbe47ef662103d0881f 100644
--- a/runtime/vm/intermediate_language_x64.cc
+++ b/runtime/vm/intermediate_language_x64.cc
@@ -2788,11 +2788,11 @@ LocationSummary* InvokeMathCFunctionInstr::MakeLocationSummary() const {
   const intptr_t kNumTemps = 0;
   LocationSummary* result =
       new LocationSummary(InputCount(), kNumTemps, LocationSummary::kCall);
-  result->set_in(0, Location::FpuRegisterLocation(XMM1, kUnboxedDouble));
+  result->set_in(0, Location::FpuRegisterLocation(XMM1));
   if (InputCount() == 2) {
-    result->set_in(1, Location::FpuRegisterLocation(XMM2, kUnboxedDouble));
+    result->set_in(1, Location::FpuRegisterLocation(XMM2));
   }
-  result->set_out(Location::FpuRegisterLocation(XMM1, kUnboxedDouble));
+  result->set_out(Location::FpuRegisterLocation(XMM1));
   return result;
 }