\begin{code}
-exprIsDupable (Type _) = True
-exprIsDupable (Var v) = True
-exprIsDupable (Lit lit) = litIsDupable lit
-exprIsDupable (Note _ e) = exprIsDupable e
+exprIsDupable (Type _) = True
+exprIsDupable (Var v) = True
+exprIsDupable (Lit lit) = litIsDupable lit
+exprIsDupable (Note InlineMe e) = True
+exprIsDupable (Note _ e) = exprIsDupable e
exprIsDupable expr
= go expr 0
where
exprIsCheap (Lit lit) = True
exprIsCheap (Type _) = True
exprIsCheap (Var _) = True
+exprIsCheap (Note InlineMe e) = True
exprIsCheap (Note _ e) = exprIsCheap e
exprIsCheap (Lam x e) = if isId x then True else exprIsCheap e
exprIsCheap (Case e _ alts) = exprIsCheap e &&
map (...redex...) is a value
Because `seq` on such things completes immediately
-A worry: constructors with unboxed args:
+A possible worry: constructors with unboxed args:
C (f x :: Int#)
-Suppose (f x) diverges; then C (f x) is not a value.
+Suppose (f x) diverges; then C (f x) is not a value. True, but
+this form is illegal (see the invariants in CoreSyn). Args of unboxed
+type must be ok-for-speculation (or trivial).
\begin{code}
exprIsValue :: CoreExpr -> Bool -- True => Value-lambda, constructor, PAP