X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FcoreSyn%2FCoreSyn.lhs;h=4c70bb33e1c0b963947407fe3f665c6d95892161;hb=49bff3215bf3fe9ada24dac2cf80f97db4e597dd;hp=12f750f12a05206075fafb3a2fdcef95ccb9cc99;hpb=9af77fa423926fbda946b31e174173d0ec5ebac8;p=ghc-hetmet.git

diff --git a/ghc/compiler/coreSyn/CoreSyn.lhs b/ghc/compiler/coreSyn/CoreSyn.lhs
index 12f750f..4c70bb3 100644
--- a/ghc/compiler/coreSyn/CoreSyn.lhs
+++ b/ghc/compiler/coreSyn/CoreSyn.lhs
@@ -79,7 +79,8 @@ data Expr b	-- "b" for the type of binders,
   | Lam   b (Expr b)
   | Let   (Bind b) (Expr b)
   | Case  (Expr b) b [Alt b]  	-- Binder gets bound to value of scrutinee
-				-- DEFAULT case must be *first*, if it occurs at all
+	-- Invariant: the list of alternatives is ALWAYS EXHAUSTIVE
+	-- Invariant: the DEFAULT case must be *first*, if it occurs at all
   | Note  Note (Expr b)
   | Type  Type			-- This should only show up at the top
 				-- level of an Arg
@@ -109,6 +110,8 @@ data Note
   | InlineMe		-- Instructs simplifer to treat the enclosed expression
 			-- as very small, and inline it at its call sites
 
+  | CoreNote String     -- A generic core annotation, propagated but not used by GHC
+
 -- NOTE: we also treat expressions wrapped in InlineMe as
 -- 'cheap' and 'dupable' (in the sense of exprIsCheap, exprIsDupable)
 -- What this means is that we obediently inline even things that don't
@@ -549,6 +552,7 @@ seqExprs [] = ()
 seqExprs (e:es) = seqExpr e `seq` seqExprs es
 
 seqNote (Coerce t1 t2) = seqType t1 `seq` seqType t2
+seqNote (CoreNote s)   = s `seq` ()
 seqNote other	       = ()
 
 seqBndr b = b `seq` ()