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

runtime/vm/intermediate_language_arm.cc

Index: runtime/vm/intermediate_language_arm.cc
===================================================================
--- runtime/vm/intermediate_language_arm.cc	(revision 35632)
+++ runtime/vm/intermediate_language_arm.cc	(working copy)
@@ -276,6 +276,27 @@
 }
 
 
+LocationSummary* UnboxedConstantInstr::MakeLocationSummary(bool opt) const {
+  const intptr_t kNumInputs = 0;
+  const intptr_t kNumTemps = 1;
+  LocationSummary* locs =
+      new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
+  locs->set_out(0, Location::RequiresFpuRegister());
+  locs->set_temp(0, Location::RequiresRegister());
+  return locs;
+}
+
+
+void UnboxedConstantInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  // The register allocator drops constant definitions that have no uses.
+  if (!locs()->out(0).IsInvalid()) {
+    DRegister dst = EvenDRegisterOf(locs()->out(0).fpu_reg());
+    Register temp = locs()->temp(0).reg();
+    __ LoadDImmediate(dst, Double::Cast(value()).value(), temp);
+  }
+}
+
+
 LocationSummary* AssertAssignableInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 0;