Optimize expressions of the form (expr === true) when expr has boolean type.

vm/il_printer.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/il_printer.h"
 
 #include "vm/intermediate_language.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, print_environments, false, "Print SSA environments.");
+DEFINE_FLAG(bool, print_types, false, "Print propagated types.");
 
 
 void BufferFormatter::Print(const char* format, ...) {
   va_list args;
   va_start(args, format);
   VPrint(format, args);
   va_end(args);
 }
 
 
@@ skipping 397 matching lines @@
 }
 
 
 void PhiInstr::PrintTo(BufferFormatter* f) const {
   f->Print("    v%d <- phi(", ssa_temp_index());
   for (intptr_t i = 0; i < inputs_.length(); ++i) {
     if (inputs_[i] != NULL) inputs_[i]->PrintTo(f);
     if (i < inputs_.length() - 1) f->Print(", ");
   }
   f->Print(")");
+  if (FLAG_print_types && HasPropagatedType()) {
+    f->Print(", propatated_type_=%s",
+             String::Handle(AbstractType::Handle(
+                 PropagatedType()).Name()).ToCString());
+  }
 }
 
 
 void ParameterInstr::PrintTo(BufferFormatter* f) const {
   f->Print("    v%d <- parameter(%d)",
            HasSSATemp() ? ssa_temp_index() : temp_index(),
            index());
 }
 
 
@@ skipping 13 matching lines @@
 
 void BindInstr::PrintTo(BufferFormatter* f) const {
   if (!is_used()) {
     f->Print("    ");
   } else if (HasSSATemp()) {
     f->Print("    v%d <- ", ssa_temp_index());
   } else {
     f->Print("    t%d <- ", temp_index());
   }
   computation()->PrintTo(f);
+  if (FLAG_print_types && HasPropagatedType()) {
+    f->Print(", propatated_type_=%s",
+             String::Handle(AbstractType::Handle(
+                 PropagatedType()).Name()).ToCString());
+  }
 }
 
 
 void PushArgumentInstr::PrintTo(BufferFormatter* f) const {
   f->Print("    %s ", DebugName());
   value()->PrintTo(f);
 }
 
 
 void ReturnInstr::PrintTo(BufferFormatter* f) const {
@@ skipping 309 matching lines @@
         !locations_[i].IsInvalid()) {
       f->Print(" [");
       locations_[i].PrintTo(f);
       f->Print("]");
     }
   }
   f->Print(" }");
 }
 
 }  // namespace dart