Refactor unboxed fields in preparation of reusable SIMD boxes

runtime/vm/intermediate_language.cc

Index: runtime/vm/intermediate_language.cc
diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index ff334db5e8bf4e4d749d593f57f8ab6b978258e0..a4bd4f9f27c82cfbff20d6109b1c7dcafcddf19b 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -151,6 +151,21 @@ bool LoadFieldInstr::IsPotentialUnboxedLoad() const {
 }
 
 
+Representation LoadFieldInstr::representation() const {
+  if (IsUnboxedLoad()) {
+    const intptr_t cid = field()->UnboxedFieldCid();
+    switch (cid) {
+      case kDoubleCid:
+        return kUnboxedDouble;
+      // TODO(johnmccutchan): Add kFloat32x4Cid here.
+      default:
+        UNREACHABLE();
+    }
+  }
+  return kTagged;
+}
+
+
 bool StoreInstanceFieldInstr::IsUnboxedStore() const {
   return FLAG_unbox_double_fields && field().IsUnboxedField();
 }
@@ -161,6 +176,22 @@ bool StoreInstanceFieldInstr::IsPotentialUnboxedStore() const {
 }
 
 
+Representation StoreInstanceFieldInstr::RequiredInputRepresentation(
+  intptr_t index) const {
+  ASSERT((index == 0) || (index == 1));
+  if ((index == 1) && IsUnboxedStore()) {
+    const intptr_t cid = field().UnboxedFieldCid();
+    switch (cid) {
+      case kDoubleCid:
+        return kUnboxedDouble;
+      default:
+        UNREACHABLE();
+    }
+  }
+  return kTagged;
+}
+
+
 bool GuardFieldInstr::AttributesEqual(Instruction* other) const {
   return field().raw() == other->AsGuardField()->field().raw();
 }