Polymorphism support for numbers and strings

src/hydrogen.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 7353 matching lines @@
     HValue* receiver,
     SmallMapList* types,
     Handle<String> name) {
   // TODO(ager): We should recognize when the prototype chains for different
   // maps are identical. In that case we can avoid repeatedly generating the
   // same prototype map checks.
   int argument_count = expr->arguments()->length() + 1;  // Includes receiver.
   HBasicBlock* join = NULL;
   FunctionSorter order[kMaxCallPolymorphism];
   int ordered_functions = 0;
+
+  Handle<Map> initial_string_map(
+      isolate()->native_context()->string_function()->initial_map());
+  Handle<Map> string_marker_map(
+      JSObject::cast(initial_string_map->prototype())->map());
+  Handle<Map> initial_number_map(
+      isolate()->native_context()->number_function()->initial_map());
+  Handle<Map> number_marker_map(
+      JSObject::cast(initial_number_map->prototype())->map());
+  Handle<Map> heap_number_map = isolate()->factory()->heap_number_map();
+
+  bool handle_smi = false;
+
   for (int i = 0;
        i < types->length() && ordered_functions < kMaxCallPolymorphism;
        ++i) {
     Handle<Map> map = types->at(i);
+    if (map.is_identical_to(number_marker_map)) handle_smi = true;
     if (expr->ComputeTarget(map, name)) {
       order[ordered_functions++] =
           FunctionSorter(i,
                          expr->target()->shared()->profiler_ticks(),
                          InliningAstSize(expr->target()),
                          expr->target()->shared()->SourceSize());
     }
   }
 
   qsort(reinterpret_cast<void*>(&order[0]),
         ordered_functions,
         sizeof(order[0]),
         &CompareHotness);
 
+  HBasicBlock* number_block = NULL;
+
   for (int fn = 0; fn < ordered_functions; ++fn) {
     int i = order[fn].index();
     Handle<Map> map = types->at(i);
     if (fn == 0) {
       // Only needed once.
-      AddInstruction(new(zone()) HCheckNonSmi(receiver));
       join = graph()->CreateBasicBlock();
+      if (handle_smi) {
+        HBasicBlock* empty_smi_block = graph()->CreateBasicBlock();
+        HBasicBlock* not_smi_block = graph()->CreateBasicBlock();
+        number_block = graph()->CreateBasicBlock();
+        HIsSmiAndBranch* smicheck = new(zone()) HIsSmiAndBranch(receiver);
+        smicheck->SetSuccessorAt(0, empty_smi_block);
+        smicheck->SetSuccessorAt(1, not_smi_block);
+        current_block()->Finish(smicheck);
+        empty_smi_block->Goto(number_block);
+        set_current_block(not_smi_block);
+      } else {
+        AddInstruction(new(zone()) HCheckNonSmi(receiver));
+      }
     }
     HBasicBlock* if_true = graph()->CreateBasicBlock();
     HBasicBlock* if_false = graph()->CreateBasicBlock();
-    HCompareMap* compare =
-        new(zone()) HCompareMap(receiver, map, if_true, if_false);
+    HUnaryControlInstruction* compare;
+
+    if (handle_smi && map.is_identical_to(number_marker_map)) {
+      compare = new(zone()) HCompareMap(
+          receiver, heap_number_map, if_true, if_false);
+      map = initial_number_map;
+      expr->set_number_check(
+          Handle<JSObject>(JSObject::cast(map->prototype())));
+    } else if (map.is_identical_to(string_marker_map)) {
+      compare = new(zone()) HIsStringAndBranch(receiver);
+      compare->SetSuccessorAt(0, if_true);
+      compare->SetSuccessorAt(1, if_false);
+      map = initial_string_map;
+      expr->set_string_check(
+          Handle<JSObject>(JSObject::cast(map->prototype())));
+    } else {
+      compare = new(zone()) HCompareMap(receiver, map, if_true, if_false);
+      expr->set_map_check();
+    }
+
     current_block()->Finish(compare);
 
+    if (expr->check_type() == NUMBER_CHECK) {
+      if_true->Goto(number_block);
+      if_true = number_block;
+      number_block->SetJoinId(expr->id());
+    }
     set_current_block(if_true);
+
     expr->ComputeTarget(map, name);
     AddCheckPrototypeMaps(expr->holder(), map);
     if (FLAG_trace_inlining && FLAG_polymorphic_inlining) {
       Handle<JSFunction> caller = info()->closure();
       SmartArrayPointer<char> caller_name =
           caller->shared()->DebugName()->ToCString();
       PrintF("Trying to inline the polymorphic call to %s from %s\n",
              *name->ToCString(),
              *caller_name);
     }
@@ skipping 3459 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal