Inline recognized List factory in the flow graph optimizer.

runtime/vm/intermediate_language.cc

 // Copyright (c) 2013, 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/intermediate_language.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_allocator.h"
@@ skipping 2899 matching lines @@
 // deoptimization occurs.
 Definition* StringInterpolateInstr::Canonicalize(FlowGraph* flow_graph) {
   // The following graph structure is generated by the graph builder:
   //   v2 <- CreateArray(v0)
   //   StoreIndexed(v2, v3, v4)   -- v3:constant index, v4: value.
   //   ..
   //   v8 <- StringInterpolate(v2)
   CreateArrayInstr* create_array = value()->definition()->AsCreateArray();
   ASSERT(create_array != NULL);
   // Check if the string interpolation has only constant inputs.
-  GrowableArray<ConstantInstr*> constants(create_array->num_elements());
-  for (intptr_t i = 0; i < create_array->num_elements(); i++) {
+  Value* num_elements = create_array->num_elements();
+  if (!num_elements->BindsToConstant() ||
+      !num_elements->BoundConstant().IsSmi()) {

[srdjan, 2014/01/30 17:55:23]

I think num_elements->BoundConstant must be a Smi, you could assert, but this
way is safe as well.

[Florian Schneider, 2014/01/31 12:43:34]

For now, I'll keep this (more general) version since it should not affect the
result.

+    return this;
+  }
+  intptr_t length = Smi::Cast(num_elements->BoundConstant()).Value();
+  GrowableArray<ConstantInstr*> constants(length);
+  for (intptr_t i = 0; i < length; i++) {
     constants.Add(NULL);
   }
   for (Value::Iterator it(create_array->input_use_list());
        !it.Done();
        it.Advance()) {
     Instruction* curr = it.Current()->instruction();
     if (curr != this) {
       StoreIndexedInstr* store = curr->AsStoreIndexed();
       ASSERT(store != NULL);
       if (store->value()->definition()->IsConstant()) {
         ASSERT(store->index()->BindsToConstant());
         const Object& obj = store->value()->definition()->AsConstant()->value();
         if (obj.IsNumber() || obj.IsString() || obj.IsBool() || obj.IsNull()) {
           constants[Smi::Cast(store->index()->BoundConstant()).Value()] =
               store->value()->definition()->AsConstant();
         } else {
           return this;
         }
       } else {
         return this;
       }
     }
   }
   // Interpolate string at compile time.
   const Array& array_argument =
-      Array::Handle(Array::New(create_array->num_elements()));
+      Array::Handle(Array::New(length));
   for (intptr_t i = 0; i < constants.length(); i++) {
     array_argument.SetAt(i, constants[i]->value());
   }
   // Build argument array to pass to the interpolation function.
   const Array& interpolate_arg = Array::Handle(Array::New(1));
   interpolate_arg.SetAt(0, array_argument);
   // Call interpolation function.
   String& concatenated = String::ZoneHandle();
   concatenated ^=
       DartEntry::InvokeFunction(CallFunction(), interpolate_arg);
@@ skipping 142 matching lines @@
     case Token::kTRUNCDIV: return 0;
     case Token::kMOD: return 1;
     default: UNIMPLEMENTED(); return -1;
   }
 }
 
 
 #undef __
 
 }  // namespace dart