Distinguish statement and expression foreign code.

lib/compiler/implementation/ssa/nodes.dart

Index: lib/compiler/implementation/ssa/nodes.dart
diff --git a/lib/compiler/implementation/ssa/nodes.dart b/lib/compiler/implementation/ssa/nodes.dart
index f657bfcc4bbc28b8987838ea9aa22b6a44f0942a..f98fb57b73453cc7a94c06d6bb642971e383ad93 100644
--- a/lib/compiler/implementation/ssa/nodes.dart
+++ b/lib/compiler/implementation/ssa/nodes.dart
@@ -1321,10 +1321,16 @@ class HLocalSet extends HFieldSet {
 }
 
 class HForeign extends HInstruction {
+  final bool _isStatement;

[Lasse Reichstein Nielsen, 2012/06/27 08:10:16]

Just make this non-private and final. No need to wrap a final field in a getter.
And make isStatement a getter, obviously :)

[floitsch, 2012/06/27 12:04:43]

Done.

   final DartString code;
   final HType foreignType;
   HForeign(this.code, DartString declaredType, List<HInstruction> inputs)
       : foreignType = computeTypeFromDeclaredType(declaredType),
+        _isStatement = false,
+        super(inputs);
+  HForeign.statement(this.code, List<HInstruction> inputs)
+      : foreignType = HType.UNKNOWN,
+        _isStatement = true,
         super(inputs);
   accept(HVisitor visitor) => visitor.visitForeign(this);
 
@@ -1339,9 +1345,7 @@ class HForeign extends HInstruction {
 
   HType get guaranteedType() => foreignType;
 
-  // Be conservative and treat all [HForeign] as statements, even
-  // though some are just expressions.
-  bool isStatement() => true;
+  bool isStatement() => _isStatement;
 }
 
 class HForeignNew extends HForeign {