Remove support for non-ssa optimizing code generation.

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/flow_graph_builder.h"
 #include "vm/hash_map.h"
 #include "vm/il_printer.h"
 #include "vm/object_store.h"
@@ skipping 348 matching lines @@
       // TODO(srdjan): Implement for mutiple targets.
       return false;
     }
     // Inline implicit instance getter.
     const String& field_name =
         String::Handle(Field::NameFromGetter(comp->function_name()));
     const Field& field = Field::Handle(GetField(class_ids[0], field_name));
     ASSERT(!field.IsNull());
 
     LoadInstanceFieldComp* load;
-    if (!use_ssa_) {
-      load = new LoadInstanceFieldComp(field,
-                                       comp->ArgumentAt(0)->value(),
-                                       comp,
-                                       true);  // Can deoptimize.
-      // TODO(fschneider): Remove the boolean parameter can_deoptimize once
-      // the non-SSA optimizer is removed.
-      load->set_ic_data(comp->ic_data());
-    } else {
-      // TODO(fschneider): Avoid generating redundant checks by checking the
-      // result-cid of the value.
-      CheckClassComp* check =
-          new CheckClassComp(comp->ArgumentAt(0)->value(), comp);
-      const ICData& unary_checks =
-          ICData::ZoneHandle(comp->ic_data()->AsUnaryClassChecks());
-      check->set_ic_data(&unary_checks);
-      BindInstr* check_instr = new BindInstr(BindInstr::kUnused, check);
-      ASSERT(instr->env() != NULL);  // Always the case with SSA.
-      // Attach the original environment to the check instruction.
-      check_instr->set_env(instr->env());
-      instr->set_env(NULL);
-      check_instr->InsertBefore(instr);
-      load = new LoadInstanceFieldComp(field,
-                                       comp->ArgumentAt(0)->value(),
-                                       NULL,
-                                       false);  // Can not deoptimize.
-    }
+    // TODO(fschneider): Avoid generating redundant checks by checking the
+    // result-cid of the value.
+    CheckClassComp* check =
+        new CheckClassComp(comp->ArgumentAt(0)->value(), comp);
+    const ICData& unary_checks =
+        ICData::ZoneHandle(comp->ic_data()->AsUnaryClassChecks());
+    check->set_ic_data(&unary_checks);
+    BindInstr* check_instr = new BindInstr(BindInstr::kUnused, check);
+    ASSERT(instr->env() != NULL);  // Always the case with SSA.
+    // Attach the original environment to the check instruction.
+    check_instr->set_env(instr->env());
+    instr->set_env(NULL);
+    check_instr->InsertBefore(instr);
+    load = new LoadInstanceFieldComp(field,
+                                     comp->ArgumentAt(0)->value(),
+                                     NULL,
+                                     false);  // Can not deoptimize.
     instr->set_computation(load);
     RemovePushArguments(comp);
     return true;
   }
 
   // Not an implicit getter.
   MethodRecognizer::Kind recognized_kind =
       MethodRecognizer::RecognizeKind(target);
 
   // VM objects length getter.
@@ skipping 245 matching lines @@
 }
 
 
 void FlowGraphTypePropagator::VisitAssertAssignable(AssertAssignableComp* comp,
                                                     BindInstr* instr) {
   if (FLAG_eliminate_type_checks &&
       !comp->is_eliminated() &&
       comp->value()->CompileTypeIsMoreSpecificThan(comp->dst_type())) {
     // TODO(regis): Remove is_eliminated_ field and support.
     comp->eliminate();
-    if (is_ssa_) {
-      UseVal* use = comp->value()->AsUse();
-      ASSERT(use != NULL);
-      Definition* result = use->definition();
-      ASSERT(result != NULL);
-      // Replace uses and remove the current instructions via the iterator.
-      instr->ReplaceUsesWith(result);
-      ASSERT(current_iterator()->Current() == instr);
-      current_iterator()->RemoveCurrentFromGraph();
-      if (FLAG_trace_optimization) {
-        OS::Print("Replacing v%d with v%d\n",
-                  instr->ssa_temp_index(),
-                  result->ssa_temp_index());
-      }
+
+    UseVal* use = comp->value()->AsUse();
+    ASSERT(use != NULL);
+    Definition* result = use->definition();
+    ASSERT(result != NULL);
+    // Replace uses and remove the current instructions via the iterator.
+    instr->ReplaceUsesWith(result);
+    ASSERT(current_iterator()->Current() == instr);
+    current_iterator()->RemoveCurrentFromGraph();
+    if (FLAG_trace_optimization) {
+      OS::Print("Replacing v%d with v%d\n",
+                instr->ssa_temp_index(),
+                result->ssa_temp_index());
     }
+
     if (FLAG_trace_type_check_elimination) {
       FlowGraphPrinter::PrintTypeCheck(parsed_function(),
                                        comp->token_pos(),
                                        comp->value(),
                                        comp->dst_type(),
                                        comp->dst_name(),
                                        comp->is_eliminated());
     }
   }
 }
 
 
 void FlowGraphTypePropagator::VisitAssertBoolean(AssertBooleanComp* comp,
                                                  BindInstr* instr) {
   // TODO(regis): Propagate NullType as well and revise the comment and code
   // below to also eliminate the test for non-null and non-constant value.
 
   // We can only eliminate an 'assert boolean' test when the checked value is
   // a constant time constant. Indeed, a variable of the proper compile time
   // type (bool) may still hold null at run time and therefore fail the test.
   if (FLAG_eliminate_type_checks &&
       !comp->is_eliminated() &&
       comp->value()->BindsToConstant() &&
       !comp->value()->BindsToConstantNull() &&
       comp->value()->CompileTypeIsMoreSpecificThan(
           Type::Handle(Type::BoolInterface()))) {
     // TODO(regis): Remove is_eliminated_ field and support.
     comp->eliminate();
-    if (is_ssa_) {
-      UseVal* use = comp->value()->AsUse();
-      ASSERT(use != NULL);
-      Definition* result = use->definition();
-      ASSERT(result != NULL);
-      // Replace uses and remove the current instructions via the iterator.
-      instr->ReplaceUsesWith(result);
-      ASSERT(current_iterator()->Current() == instr);
-      current_iterator()->RemoveCurrentFromGraph();
-      if (FLAG_trace_optimization) {
-        OS::Print("Replacing v%d with v%d\n",
-                  instr->ssa_temp_index(),
-                  result->ssa_temp_index());
-      }
+
+    UseVal* use = comp->value()->AsUse();
+    ASSERT(use != NULL);
+    Definition* result = use->definition();
+    ASSERT(result != NULL);
+    // Replace uses and remove the current instructions via the iterator.
+    instr->ReplaceUsesWith(result);
+    ASSERT(current_iterator()->Current() == instr);
+    current_iterator()->RemoveCurrentFromGraph();
+    if (FLAG_trace_optimization) {
+      OS::Print("Replacing v%d with v%d\n",
+                instr->ssa_temp_index(),
+                result->ssa_temp_index());
     }
+
     if (FLAG_trace_type_check_elimination) {
       const String& name = String::Handle(Symbols::New("boolean expression"));
       FlowGraphPrinter::PrintTypeCheck(parsed_function(),
                                        comp->token_pos(),
                                        comp->value(),
                                        Type::Handle(Type::BoolInterface()),
                                        name,
                                        comp->is_eliminated());
     }
   }
 }
 
 
 void FlowGraphTypePropagator::VisitInstanceOf(InstanceOfComp* comp,
                                               BindInstr* instr) {
   // TODO(regis): Propagate NullType as well and revise the comment and code
   // below to also eliminate the test for non-null and non-constant value.
 
   // We can only eliminate an 'instance of' test when the checked value is
   // a constant time constant. Indeed, a variable of the proper compile time
   // type may still hold null at run time and therefore fail the test.
   // We do not bother checking for Object destination type, since the graph
   // builder did already.
   if (FLAG_eliminate_type_checks &&
       comp->value()->BindsToConstant() &&
       !comp->value()->BindsToConstantNull() &&
       comp->value()->CompileTypeIsMoreSpecificThan(comp->type())) {
-    if (is_ssa_) {
-      UseVal* use = comp->value()->AsUse();
-      ASSERT(use != NULL);
-      Definition* result = use->definition();
-      ASSERT(result != NULL);
-      // Replace uses and remove the current instructions via the iterator.
-      instr->ReplaceUsesWith(result);
-      ASSERT(current_iterator()->Current() == instr);
-      current_iterator()->RemoveCurrentFromGraph();
-      if (FLAG_trace_optimization) {
-        OS::Print("Replacing v%d with v%d\n",
-                  instr->ssa_temp_index(),
-                  result->ssa_temp_index());
-      }
+    UseVal* use = comp->value()->AsUse();
+    ASSERT(use != NULL);
+    Definition* result = use->definition();
+    ASSERT(result != NULL);
+    // Replace uses and remove the current instructions via the iterator.
+    instr->ReplaceUsesWith(result);
+    ASSERT(current_iterator()->Current() == instr);
+    current_iterator()->RemoveCurrentFromGraph();
+    if (FLAG_trace_optimization) {
+      OS::Print("Replacing v%d with v%d\n",
+                instr->ssa_temp_index(),
+                result->ssa_temp_index());
     }
+
     if (FLAG_trace_type_check_elimination) {
       const String& name = String::Handle(Symbols::New("InstanceOf"));
       FlowGraphPrinter::PrintTypeCheck(parsed_function(),
                                        comp->token_pos(),
                                        comp->value(),
                                        comp->type(),
                                        name,
                                        /* eliminated = */ true);
     }
   }
@@ skipping 170 matching lines @@
         OS::Print("Replacing v%d with v%d\n",
                   instr->ssa_temp_index(),
                   result->ssa_temp_index());
       }
     }
   }
 }
 
 
 }  // namespace dart