Convert diamond shaped control flow into a single conditional instruction.

runtime/vm/intermediate_language_arm.cc

 // Copyright (c) 2013, 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_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "lib/error.h"
@@ skipping 85 matching lines @@
   // Generate 2 NOP instructions so that the debugger can patch the return
   // pattern (1 instruction) with a call to the debug stub (3 instructions).
   __ nop();
   __ nop();
   compiler->AddCurrentDescriptor(PcDescriptors::kReturn,
                                  Isolate::kNoDeoptId,
                                  token_pos());
 }
 
 
+bool IfThenElseInstr::IsSupported() {
+  return false;
+}
+
+
+bool IfThenElseInstr::Supports(ComparisonInstr* comparison,
+                               Value* v1,
+                               Value* v2) {
+  UNREACHABLE();
+  return false;
+}
+
+
+LocationSummary* IfThenElseInstr::MakeLocationSummary() const {
+  UNREACHABLE();
+  return NULL;
+}
+
+
+void IfThenElseInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  UNREACHABLE();
+}
+
+
 LocationSummary* ClosureCallInstr::MakeLocationSummary() const {
   UNIMPLEMENTED();
   return NULL;
 }
 
 
 LocationSummary* LoadLocalInstr::MakeLocationSummary() const {
   return LocationSummary::Make(0,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
@@ skipping 1639 matching lines @@
 
 
 void CreateClosureInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   UNIMPLEMENTED();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM