Improve ShouldSpecializeForDouble to handle ICs with multiple checks.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/hash_map.h"
@@ skipping 248 matching lines @@
   return ICDataHasOnlyReceiverArgumentClassIds(ic_data, class_ids, class_ids);
 }
 
 
 static bool HasOneDouble(const ICData& ic_data) {
   return ICDataHasReceiverClassId(ic_data, kDoubleCid);
 }
 
 
 static bool ShouldSpecializeForDouble(const ICData& ic_data) {
-  if (ic_data.NumberOfChecks() != 1) return false;
+  if (ic_data.NumberOfChecks() < 1) return false;
   if (ic_data.num_args_tested() != 2) return false;
 
-  Function& target = Function::Handle();
-  GrowableArray<intptr_t> class_ids;
-  ic_data.GetCheckAt(0, &class_ids, &target);
-  ASSERT(class_ids.length() == 2);
+  for (intptr_t check_idx = 0;
+       check_idx < ic_data.NumberOfChecks();
+       check_idx++) {
+    Function& target = Function::Handle();
+    GrowableArray<intptr_t> class_ids;
+    ic_data.GetCheckAt(check_idx, &class_ids, &target);
+    ASSERT(class_ids.length() == 2);
 
-  const bool seen_double =
-      (class_ids[0] == kDoubleCid) || (class_ids[1] == kDoubleCid);
+    const bool seen_double =

[Florian Schneider, 2012/09/21 13:23:07]

It would be nice to have a helper that checks for at the combinations of
smi/double with least one double.

+        (class_ids[0] == kDoubleCid) || (class_ids[1] == kDoubleCid);
 
-  const bool seen_only_smi_or_double =
-      ((class_ids[0] == kDoubleCid) || (class_ids[0] == kSmiCid)) &&
-      ((class_ids[1] == kDoubleCid) || (class_ids[1] == kSmiCid));
+    const bool seen_only_smi_or_double =
+        ((class_ids[0] == kDoubleCid) || (class_ids[0] == kSmiCid)) &&
+        ((class_ids[1] == kDoubleCid) || (class_ids[1] == kSmiCid));
 
-  return seen_double && seen_only_smi_or_double;
+    if (!seen_double || !seen_only_smi_or_double) {
+      return false;
+    }
+  }
+  return true;
 }
 
 
 static void RemovePushArguments(InstanceCallInstr* call) {
   // Remove original push arguments.
   for (intptr_t i = 0; i < call->ArgumentCount(); ++i) {
     PushArgumentInstr* push = call->ArgumentAt(i);
     push->ReplaceUsesWith(push->value()->definition());
     push->RemoveFromGraph();
   }
@@ skipping 2193 matching lines @@
        it.Advance()) {
     JoinEntryInstr* join = it.Current()->AsJoinEntry();
     if (join != NULL) join->EliminateUnreachablePhiInputs();
   }
 
   graph_->ComputeUseLists();
 }
 
 
 }  // namespace dart