Cleanups, refactoring in anticipation of new string interpolation nodes. Removed unnecessary code.

runtime/vm/flow_graph_optimizer.cc

Index: runtime/vm/flow_graph_optimizer.cc
===================================================================
--- runtime/vm/flow_graph_optimizer.cc	(revision 28616)
+++ runtime/vm/flow_graph_optimizer.cc	(working copy)
@@ -6049,80 +6049,6 @@
 
 void ConstantPropagator::VisitStaticCall(StaticCallInstr* instr) {
   SetValue(instr, non_constant_);
-  return;
-  // TODO(srdjan): Enable code below once issues resolved.
-  if (IsNonConstant(instr->constant_value())) {
-    // Do not bother with costly analysis if we already know that the
-    // instruction is not a constant.
-    SetValue(instr, non_constant_);
-    return;
-  }
-  MethodRecognizer::Kind recognized_kind =
-      MethodRecognizer::RecognizeKind(instr->function());
-  if (recognized_kind == MethodRecognizer::kStringBaseInterpolate) {
-    // static String _interpolate(List values)
-    //
-    // Code for calling interpolate is generated by the compiler:
-    //   v2 <- CreateArray(v0)
-    //   StoreIndexed(v2, v3, v4)   -- v3:constant index, v4: value.
-    //   ..
-    //   PushArgument(v2)
-    //   v8 <- StaticCall(_interpolate, v2)
-    // Detect that all values are constant, interpolate at compile
-    // time.
-    ASSERT(instr->ArgumentCount() == 1);
-    CreateArrayInstr* create_array = instr->ArgumentAt(0)->AsCreateArray();
-    ASSERT(create_array != NULL);
-    // Check if the string interpolation has only constant inputs.
-    for (Value::Iterator it(create_array->input_use_list());
-         !it.Done();
-         it.Advance()) {
-      Instruction* curr = it.Current()->instruction();
-      StoreIndexedInstr* store = curr->AsStoreIndexed();
-      // 'store' is NULL fir PushArgument instruction: skip it.
-      if ((store != NULL) &&
-          (IsNonConstant(store->value()->definition()->constant_value()))) {
-        SetValue(instr, non_constant_);
-        return;
-      }
-    }
-    // Interpolate string at compile time.
-    const Array& value_arr =
-        Array::Handle(Array::New(create_array->num_elements()));
-    // Build the array of literal values to interpolate, abort if a value is
-    // not literal.
-    for (Value::Iterator it(create_array->input_use_list());
-         !it.Done();
-         it.Advance()) {
-      Instruction* curr = it.Current()->instruction();
-      StoreIndexedInstr* store = curr->AsStoreIndexed();
-      if (store == NULL) {
-        ASSERT(curr == instr->PushArgumentAt(0));
-      } else {
-        Value* index_value = store->index();
-        ASSERT(index_value->BindsToConstant() && index_value->IsSmiValue());
-        const intptr_t ix = Smi::Cast(index_value->BoundConstant()).Value();
-        ASSERT(IsConstant(store->value()->definition()->constant_value()));
-        value_arr.SetAt(ix, store->value()->definition()->constant_value());
-      }
-    }
-    // Build argument array to pass to the interpolation function.
-    const Array& interpolate_arg = Array::Handle(Array::New(1));
-    interpolate_arg.SetAt(0, value_arr);
-    // Call interpolation function.
-    String& concatenated = String::ZoneHandle();
-    concatenated ^=
-        DartEntry::InvokeFunction(instr->function(), interpolate_arg);
-    if (concatenated.IsUnhandledException()) {
-      SetValue(instr, non_constant_);
-      return;
-    }
-
-    concatenated = Symbols::New(concatenated);
-    SetValue(instr, concatenated);
-  } else {
-    SetValue(instr, non_constant_);
-  }
 }
 
 
@@ -6955,27 +6881,6 @@
 }
 
 
-// Code for calling interpolate is generated by the compiler:
-//   v2 <- CreateArray(v0)
-//   StoreIndexed(v2, v3, v4)   -- v3:constant index, v4: value.
-//   ..
-//   PushArgument(v2)
-//   v8 <- StaticCall(_interpolate, v2)
-// Remove the inputs.
-void ConstantPropagator::RemoveInterpolationInputs(
-    const StaticCallInstr& call) {
-  ASSERT(call.ArgumentCount() == 1);
-  CreateArrayInstr* create_array = call.ArgumentAt(0)->AsCreateArray();
-  ASSERT(create_array != NULL);
-  for (Value* use = create_array->input_use_list();
-      use != NULL;
-      use = create_array->input_use_list()) {
-    use->instruction()->RemoveFromGraph();
-  }
-  create_array->RemoveFromGraph();
-}
-
-
 void ConstantPropagator::Transform() {
   if (FLAG_trace_constant_propagation) {
     OS::Print("\n==== Before constant propagation ====\n");
@@ -7083,13 +6988,6 @@
         ConstantInstr* constant = graph_->GetConstant(defn->constant_value());
         defn->ReplaceUsesWith(constant);
         i.RemoveCurrentFromGraph();
-        if (defn->IsStaticCall()) {
-          MethodRecognizer::Kind recognized_kind =
-              MethodRecognizer::RecognizeKind(defn->AsStaticCall()->function());
-          if (recognized_kind == MethodRecognizer::kStringBaseInterpolate) {
-            RemoveInterpolationInputs(*defn->AsStaticCall());
-          }
-        }
       }
     }