dart2js: permit generation of conditionals as arguments of allocations.

pkg/compiler/lib/src/ssa/codegen_helpers.dart

 // 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.
 
 part of ssa;
 
 /**
  * Replaces some instructions with specialized versions to make codegen easier.
  * Caches codegen information on nodes.
  */
@@ skipping 619 matching lines @@
     for (HInstruction temp = block.first;
          !identical(temp, instruction);
          temp = temp.next) {
       if (!generateAtUseSite.contains(temp)) return true;
     }
 
     return false;
   }
 
   bool isSafeToGenerateAtUseSite(HInstruction user, HInstruction input) {
+    // HForeignNew evaluates arguments in order and passes them to a
+    // constructor.
+    if (user is HForeignNew) return true;
     // A [HForeign] instruction uses operators and if we generate
     // [input] at use site, the precedence might be wrong.
     if (user is HForeign) return false;
     // A [HCheck] instruction with control flow uses its input
     // multiple times, so we avoid generating it at use site.
     if (user is HCheck && user.isControlFlow()) return false;
     // A [HIs] instruction uses its input multiple times, so we
     // avoid generating it at use site.
     if (user is HIs) return false;
     return true;
@@ skipping 102 matching lines @@
     }
 
     // If [thenInput] is defined in the first predecessor, then it is only used
     // by [phi] and can be generated at use site.
     if (identical(thenInput.block, end.predecessors[0])) {
       assert(thenInput.usedBy.length == 1);
       markAsGenerateAtUseSite(thenInput);
     }
   }
 }