Fix crashes in Smi equality comparisons: Smi equality instruction may have null as inputs. Null is …

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 555 matching lines @@
   __ jmp(&done);
   __ Bind(&non_null_compare);  // Receiver is not null.
   __ pushq(left);
   __ pushq(right);
   EmitEqualityAsPolymorphicCall(compiler, ic_data, locs, branch, kind,
                                 deopt_id, token_pos);
   __ Bind(&done);
 }
 
 
-Immediate SmiConstantToImmediate(const Object& constant) {
-  ASSERT(constant.IsSmi());
-  return Immediate(reinterpret_cast<int64_t>(constant.raw()));
-}
-
-
 static void EmitSmiComparisonOp(FlowGraphCompiler* compiler,
                                 const LocationSummary& locs,
                                 Token::Kind kind,
                                 BranchInstr* branch) {
   Location left = locs.in(0);
   Location right = locs.in(1);
 
   Condition true_condition = TokenKindToSmiCondition(kind);
 
   if (left.IsConstant() && right.IsConstant()) {
     // TODO(vegorov): should be eliminated earlier by constant propagation.
     const bool result = FlowGraphCompiler::EvaluateCondition(
         true_condition,
         Smi::Cast(left.constant()).Value(),
         Smi::Cast(right.constant()).Value());
 
     if (branch != NULL) {
       branch->EmitBranchOnValue(compiler, result);
     } else {
       __ LoadObject(locs.out().reg(), result ? compiler->bool_true()
                                              : compiler->bool_false());
     }
 
     return;
   }
 
   if (left.IsConstant()) {
-    __ cmpq(right.reg(), SmiConstantToImmediate(left.constant()));
+    __ CompareObject(right.reg(), left.constant());
     true_condition = FlowGraphCompiler::FlipCondition(true_condition);
   } else if (right.IsConstant()) {
-    __ cmpq(left.reg(), SmiConstantToImmediate(right.constant()));
+    __ CompareObject(left.reg(), right.constant());
   } else {
     __ cmpq(left.reg(), right.reg());
   }
 
   if (branch != NULL) {
     branch->EmitBranchOnCondition(compiler, true_condition);
   } else {
     Register result = locs.out().reg();
     Label done, is_true;
     __ j(true_condition, &is_true);
@@ skipping 1659 matching lines @@
 void UnboxedMintBinaryOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   UNIMPLEMENTED();
 }
 
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64