[project @ 2001-09-26 15:12:33 by simonpj]

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

diff --git a/ghc/compiler/basicTypes/BasicTypes.lhs b/ghc/compiler/basicTypes/BasicTypes.lhs
index 0f7a462..a4e6260 100644 (file)
--- a/ghc/compiler/basicTypes/BasicTypes.lhs
+++ b/ghc/compiler/basicTypes/BasicTypes.lhs
@@ -38,7 +38,10 @@ module BasicTypes(
 
         EP(..),
 
-       StrictnessMark(..), isMarkedUnboxed, isMarkedStrict
+       StrictnessMark(..), isMarkedUnboxed, isMarkedStrict,
+
+       CompilerPhase, pprPhase, 
+       Activation(..), isActive, isNeverActive, isAlwaysActive
    ) where
 
 #include "HsVersions.h"
@@ -289,7 +292,7 @@ isDeadOcc other       = False
 
 isFragileOcc :: OccInfo -> Bool
 isFragileOcc (OneOcc _ _) = True
-isFragileOcc other           = False
+isFragileOcc other       = False
 \end{code}
 
 \begin{code}
@@ -335,3 +338,43 @@ instance Outputable StrictnessMark where
   ppr MarkedUnboxed    = ptext SLIT("! !")
   ppr NotMarkedStrict  = empty
 \end{code}
+
+
+%************************************************************************
+%*                                                                     *
+\subsection{Activation}
+%*                                                                     *
+%************************************************************************
+
+When a rule or inlining is active
+
+\begin{code}
+type CompilerPhase = Int       -- Compilation phase
+                               -- Phases decrease towards zero
+                               -- Zero is the last phase
+
+pprPhase :: CompilerPhase -> SDoc
+pprPhase n = brackets (int n)
+
+data Activation = NeverActive
+               | AlwaysActive
+               | ActiveAfter CompilerPhase     -- Active in this phase and later
+               deriving( Eq )                  -- Eq used in comparing rules in HsDecls
+
+instance Outputable Activation where
+   ppr AlwaysActive    = empty         -- The default
+   ppr (ActiveAfter n) = pprPhase n
+   ppr NeverActive     = ptext SLIT("NEVER")
+    
+isActive :: CompilerPhase -> Activation -> Bool
+isActive p NeverActive     = False
+isActive p AlwaysActive    = True
+isActive p (ActiveAfter n) = p <= n
+
+isNeverActive, isAlwaysActive :: Activation -> Bool
+isNeverActive NeverActive = True
+isNeverActive act        = False
+
+isAlwaysActive AlwaysActive = True
+isAlwaysActive other       = False
+\end{code}
\ No newline at end of file