Eliminate class UseVal.

runtime/vm/intermediate_language_x64.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/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 1072 matching lines @@
   compiler->GenerateCall(token_pos(),
                          try_index(),
                          &StubCode::AllocateArrayLabel(),
                          PcDescriptors::kOther,
                          locs());
   ASSERT(locs()->out().reg() == RAX);
 
   // Pop the element values from the stack into the array.
   __ leaq(R10, FieldAddress(RAX, Array::data_offset()));
   for (int i = ArgumentCount() - 1; i >= 0; --i) {
-    ASSERT(ArgumentAt(i)->value()->IsUse());
     __ popq(Address(R10, i * kWordSize));
   }
 }
 
 
 LocationSummary*
     AllocateObjectWithBoundsCheckComp::MakeLocationSummary() const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
@@ skipping 177 matching lines @@
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(0, Location::RequiresRegister());
   locs->set_out(Location::SameAsFirstInput());
   return locs;
 }
 
 
 void ExtractConstructorInstantiatorComp::EmitNativeCode(
     FlowGraphCompiler* compiler) {
-  ASSERT(instantiator()->IsUse());
   Register instantiator_reg = locs()->in(0).reg();
   ASSERT(locs()->out().reg() == instantiator_reg);
 
   // instantiator_reg is the instantiator AbstractTypeArguments object
   // (or null).  If the instantiator is null and if the type argument vector
   // instantiated from null becomes a vector of Dynamic, then use null as
   // the type arguments and do not pass the instantiator.
   Label done;
   const intptr_t len = type_arguments().Length();
   if (type_arguments().IsRawInstantiatedRaw(len)) {
@@ skipping 962 matching lines @@
   }
   __ j(ABOVE_EQUAL, deopt);
 }
 
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64