Prettify !(x rel-op y) into (x "!rel-op" y) when possible.

lib/compiler/implementation/ssa/codegen.dart

Index: lib/compiler/implementation/ssa/codegen.dart
diff --git a/lib/compiler/implementation/ssa/codegen.dart b/lib/compiler/implementation/ssa/codegen.dart
index 94c13c606302476eb09f8abc939e83d83bd85821..a6ec43c938d1f5312d50ff27d16ba4895b76db2a 100644
--- a/lib/compiler/implementation/ssa/codegen.dart
+++ b/lib/compiler/implementation/ssa/codegen.dart
@@ -1397,9 +1397,35 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
 
   visitNot(HNot node) {
     assert(node.inputs.length == 1);
+    HInstruction input = node.inputs[0];
+    if (input is HBoolify && isGenerateAtUseSite(input)) {
+      beginExpression(JSPrecedence.EQUALITY_PRECEDENCE);
+      assert(node.inputs.length == 1);
+      use(node.inputs[0], JSPrecedence.EQUALITY_PRECEDENCE);
+      buffer.add(' !== true');
+      endExpression(JSPrecedence.EQUALITY_PRECEDENCE);
+      return;

[ngeoffray, 2012/05/08 09:27:24]

I prefer else if than return.

[Lasse Reichstein Nielsen, 2012/05/08 10:03:33]

Done.

+    }
+    if (input is HRelational &&
+        input.builtin &&
+        isGenerateAtUseSite(input)) {
+      Map<String, String> inverseOperator = const <String>{
+        "==" : "!=",
+        "!=" : "==",
+        "===": "!==",
+        "!==": "===",
+        "<"  : ">=",
+        "<=" : ">",
+        ">"  : "<=",
+        ">=" : "<"
+      };
+      visitInvokeBinary(input,
+                        inverseOperator[input.operation.name.stringValue]);
+      return;

[ngeoffray, 2012/05/08 09:27:24]

ditto.

[Lasse Reichstein Nielsen, 2012/05/08 10:03:33]

Done.

+    }
     beginExpression(JSPrecedence.PREFIX_PRECEDENCE);
     buffer.add('!');
-    use(node.inputs[0], JSPrecedence.PREFIX_PRECEDENCE);
+    use(input, JSPrecedence.PREFIX_PRECEDENCE);
     endExpression(JSPrecedence.PREFIX_PRECEDENCE);
   }