Add inlineAppliedVars optimisation

puffnfresh · puffnfresh · commit bc79f0694e05 · 2015-04-20T23:00:05.000-06:00
Translates the following:

    (function(a) {
      return a * a * a;
    })(b)

Into:

    b * b * b
diff --git a/src/Language/PureScript/CodeGen/JS/Optimizer.hs b/src/Language/PureScript/CodeGen/JS/Optimizer.hs
@@ -78,7 +78,8 @@ optimize' js = do
     , inlineOperator (C.prelude, (C.#)) $ \x f -> JSApp f [x]
     , inlineOperator (C.preludeUnsafe, C.unsafeIndex) $ flip JSIndexer
     , inlineCommonOperators
-    , inlineAppliedArrComposition ]) js
+    , inlineAppliedArrComposition
+    , inlineAppliedVars ]) js
 
 untilFixedPoint :: (Monad m, Eq a) => (a -> m a) -> a -> m a
 untilFixedPoint f = go
diff --git a/src/Language/PureScript/CodeGen/JS/Optimizer/Inliner.hs b/src/Language/PureScript/CodeGen/JS/Optimizer/Inliner.hs
@@ -19,6 +19,7 @@ module Language.PureScript.CodeGen.JS.Optimizer.Inliner (
   inlineOperator,
   inlineCommonOperators,
   inlineAppliedArrComposition,
+  inlineAppliedVars,
   etaConvert,
   unThunk,
   evaluateIifes
@@ -246,6 +247,13 @@ inlineAppliedArrComposition = everywhereOnJS convert
   convert (JSApp (JSApp (JSApp (JSApp fn [dict']) [x]) [y]) [z]) | isDict semigroupoidArr dict' && isPreludeFn (C.<<<) fn = JSApp x [JSApp y [z]]
   convert other = other
 
+inlineAppliedVars :: JS -> JS
+inlineAppliedVars = everywhereOnJS convert
+  where
+  convert :: JS -> JS
+  convert (JSApp (JSFunction Nothing [a] (JSBlock [JSReturn b])) [JSVar x]) = replaceIdent a (JSVar x) b
+  convert other = other
+
 isDict :: (String, String) -> JS -> Bool
 isDict (moduleName, dictName) (JSAccessor x (JSVar y)) = x == dictName && y == moduleName
 isDict _ _ = False
