Add {-# OPTIONS_GHC -w #-} and some blurb to all compiler modules

[ghc-hetmet.git] / compiler / basicTypes / IdInfo.lhs

diff --git a/compiler/basicTypes/IdInfo.lhs b/compiler/basicTypes/IdInfo.lhs
index 38e2a2e..7580703 100644 (file)
--- a/compiler/basicTypes/IdInfo.lhs
+++ b/compiler/basicTypes/IdInfo.lhs
@@ -8,6 +8,13 @@
 Haskell. [WDP 94/11])
 
 \begin{code}
+{-# OPTIONS_GHC -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/WorkingConventions#Warnings
+-- for details
+
 module IdInfo (
        GlobalIdDetails(..), notGlobalId,       -- Not abstract
 
@@ -71,7 +78,10 @@ module IdInfo (
        CafInfo(..), cafInfo, ppCafInfo, setCafInfo, mayHaveCafRefs,
 
         -- Lambda-bound variable info
-        LBVarInfo(..), lbvarInfo, setLBVarInfo, noLBVarInfo, hasNoLBVarInfo
+        LBVarInfo(..), lbvarInfo, setLBVarInfo, noLBVarInfo, hasNoLBVarInfo,
+
+        -- Tick-box info
+        TickBoxOp(..), TickBoxId,
     ) where
 
 #include "HsVersions.h"
@@ -87,6 +97,7 @@ import TyCon
 import ForeignCall
 import NewDemand
 import Outputable      
+import Module
 
 import Data.Maybe
 
@@ -215,7 +226,7 @@ seqNewDemandInfo (Just dmd) = seqDemand dmd
 
 %************************************************************************
 %*                                                                     *
-\subsection{GlobalIdDetails
+\subsection{GlobalIdDetails}
 %*                                                                     *
 %************************************************************************
 
@@ -228,7 +239,8 @@ data GlobalIdDetails
   = VanillaGlobal              -- Imported from elsewhere, a default method Id.
 
   | RecordSelId                 -- The Id for a record selector
-    { sel_tycon   :: TyCon
+    { sel_tycon   :: TyCon     -- For a data type family, this is the *instance* TyCon
+                               --      not the family TyCon
     , sel_label   :: FieldLabel
     , sel_naughty :: Bool       -- True <=> naughty
     }                          -- See Note [Naughty record selectors]
@@ -246,6 +258,8 @@ data GlobalIdDetails
   | PrimOpId PrimOp            -- The Id for a primitive operator
   | FCallId ForeignCall                -- The Id for a foreign call
 
+  | TickBoxOpId TickBoxOp      -- The Id for a tick box (both traditional and binary)
+
   | NotGlobalId                        -- Used as a convenient extra return value from globalIdDetails
     
 notGlobalId = NotGlobalId
@@ -258,6 +272,7 @@ instance Outputable GlobalIdDetails where
     ppr (ClassOpId _)     = ptext SLIT("[ClassOp]")
     ppr (PrimOpId _)      = ptext SLIT("[PrimOp]")
     ppr (FCallId _)       = ptext SLIT("[ForeignCall]")
+    ppr (TickBoxOpId _)   = ptext SLIT("[TickBoxOp]")
     ppr (RecordSelId {})  = ptext SLIT("[RecSel]")
 \end{code}
 
@@ -456,9 +471,11 @@ type InlinePragInfo = Activation
 %************************************************************************
 
 \begin{code}
--- CoreRules is used only in an idSpecialisation (move to IdInfo?)
 data SpecInfo 
-  = SpecInfo [CoreRule] VarSet -- Locally-defined free vars of RHSs
+  = SpecInfo 
+       [CoreRule] 
+       VarSet          -- Locally-defined free vars of *both* LHS and RHS of rules
+                       -- Note [Rule dependency info]
 
 emptySpecInfo :: SpecInfo
 emptySpecInfo = SpecInfo [] emptyVarSet
@@ -475,6 +492,17 @@ specInfoRules (SpecInfo rules _) = rules
 seqSpecInfo (SpecInfo rules fvs) = seqRules rules `seq` seqVarSet fvs
 \end{code}
 
+Note [Rule dependency info]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+THe VarSet in a SpecInfo is used for dependency analysis in the 
+occurrence analyser.  We must track free vars in *both* lhs and rhs.  Why both?  
+Consider
+       x = y
+       RULE f x = 4
+Then if we substitute y for x, we'd better do so in the
+ rule's LHS too, so we'd better ensure the dependency is respsected
+
+
 
 %************************************************************************
 %*                                                                     *
@@ -695,6 +723,25 @@ zapDemandInfo info@(IdInfo {newDemandInfo = dmd})
 
 \begin{code}
 zapFragileInfo :: IdInfo -> Maybe IdInfo
+-- Zap info that depends on free variables
 zapFragileInfo info = Just (info `setSpecInfo` emptySpecInfo
+                                `setWorkerInfo` NoWorker
                                  `setUnfoldingInfo` NoUnfolding)
 \end{code}
+
+%************************************************************************
+%*                                                                     *
+\subsection{TickBoxOp}
+%*                                                                     *
+%************************************************************************
+
+\begin{code}
+type TickBoxId = Int
+
+data TickBoxOp 
+   = TickBox Module {-# UNPACK #-} !TickBoxId
+          -- ^Tick box for Hpc-style coverage
+
+instance Outputable TickBoxOp where
+    ppr (TickBox mod n)         = ptext SLIT("tick") <+> ppr (mod,n)
+\end{code}