Remove restriction when computing instructions that can be generate at use site.

lib/compiler/implementation/ssa/codegen_helpers.dart

Index: lib/compiler/implementation/ssa/codegen_helpers.dart
===================================================================
--- lib/compiler/implementation/ssa/codegen_helpers.dart	(revision 6682)
+++ lib/compiler/implementation/ssa/codegen_helpers.dart	(working copy)
@@ -134,20 +134,10 @@
         generateAtUseSite.add(instruction);
         continue;
       }
-      bool foundInInputs = false;
       // See if the current instruction is the next non-trivial
-      // expected input. If not, drop the expectedInputs and
-      // start over.
-      if (findInInputs(instruction)) {
-        foundInInputs = true;
-        tryGenerateAtUseSite(instruction);
-      } else {
-        assert(expectedInputs.isEmpty());
-      }
-      if (foundInInputs || usedOnlyByPhis(instruction)) {
-        // Try merging all non-trivial inputs.
-        instruction.accept(this);
-      }
+      // expected input.
+      if (findInInputs(instruction)) tryGenerateAtUseSite(instruction);

[floitsch, 2012/04/18 13:13:24]

as discussed change this to findInInputsAndPopNonMatching.
and keep the 'else assert(...isEmpty())'.

[ngeoffray, 2012/04/18 13:17:19]

Done.

+      instruction.accept(this);
     }
 
     if (block.predecessors.length === 1