Refactor handling of source map information.

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 16 matching lines @@
       HInstruction next = instruction.next;
       HInstruction replacement = instruction.accept(this);
       if (replacement != instruction && replacement != null) {
         block.rewrite(instruction, replacement);
 
         // If the replacement instruction does not know its source element, use
         // the source element of the instruction.
         if (replacement.sourceElement == null) {
           replacement.sourceElement = instruction.sourceElement;
         }
-        if (replacement.sourcePosition == null) {
-          replacement.sourcePosition = instruction.sourcePosition;
+        if (replacement.sourceInformation == null) {
+          replacement.sourceInformation = instruction.sourceInformation;
         }
         if (!replacement.isInBasicBlock()) {
           // The constant folding can return an instruction that is already
           // part of the graph (like an input), so we only add the replacement
           // if necessary.
           block.addAfter(instruction, replacement);
           // Visit the replacement as the next instruction in case it can also
           // be constant folded away.
           next = replacement;
         }
@@ skipping 681 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);
     }
   }
 }