AOT: Enable branch merging for checked smi comparisons

runtime/vm/intermediate_language_ia32.cc

Index: runtime/vm/intermediate_language_ia32.cc
diff --git a/runtime/vm/intermediate_language_ia32.cc b/runtime/vm/intermediate_language_ia32.cc
index 10293010ca345ee68fa1d23c6a57b7fb7a7d7300..e281ab5dc917aedaaee7e367ca05711b46071040 100644
--- a/runtime/vm/intermediate_language_ia32.cc
+++ b/runtime/vm/intermediate_language_ia32.cc
@@ -2802,6 +2802,35 @@ void CheckedSmiOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
 }
 
 
+LocationSummary* CheckedSmiComparisonInstr::MakeLocationSummary(
+    Zone* zone, bool opt) const {
+  // Only for precompiled code, not on ia32 currently.
+  UNIMPLEMENTED();
+  return NULL;
+}
+
+
+Condition CheckedSmiComparisonInstr::EmitComparisonCode(
+    FlowGraphCompiler* compiler, BranchLabels labels) {
+  // Only for precompiled code, not on ia32 currently.
+  UNIMPLEMENTED();
+  return ZERO;
+}
+
+
+void CheckedSmiComparisonInstr::EmitBranchCode(FlowGraphCompiler* compiler,
+                                               BranchInstr* instr) {
+  // Only for precompiled code, not on ia32 currently.
+  UNIMPLEMENTED();
+}
+
+
+void CheckedSmiComparisonInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  // Only for precompiled code, not on ia32 currently.
+  UNIMPLEMENTED();
+}
+
+
 static bool IsSmiValue(const Object& constant, intptr_t value) {
   return constant.IsSmi() && (Smi::Cast(constant).Value() == value);
 }