X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fcmm%2FCmmExpr.hs;h=1769a01466c4f6a1205fc5d0c5f315493506aabf;hb=11db0bc8cd2eee13339578ca447c0a2d97f453c3;hp=791731b1aa379e3711bf689049e795ec7fab81e2;hpb=7ed4f0716220b03fe5e04100ddbbc9e37d5323fe;p=ghc-hetmet.git

diff --git a/compiler/cmm/CmmExpr.hs b/compiler/cmm/CmmExpr.hs
index 791731b..1769a01 100644
--- a/compiler/cmm/CmmExpr.hs
+++ b/compiler/cmm/CmmExpr.hs
@@ -1,4 +1,3 @@
-{-# OPTIONS -Wall -fno-warn-name-shadowing #-}
 
 module CmmExpr
     ( CmmExpr(..), cmmExprRep, maybeInvertCmmExpr
@@ -6,7 +5,7 @@ module CmmExpr
     , CmmLit(..), cmmLitRep
     , LocalReg(..), localRegRep, localRegGCFollow, GCKind(..)
     , GlobalReg(..), globalRegRep, spReg, hpReg, spLimReg, nodeReg, node
-    , UserOfLocalRegs, foldRegsUsed
+    , UserOfLocalRegs, foldRegsUsed, filterRegsUsed
     , RegSet, emptyRegSet, elemRegSet, extendRegSet, deleteFromRegSet, mkRegSet
             , plusRegSet, minusRegSet, timesRegSet
     )
@@ -113,6 +112,11 @@ timesRegSet      = intersectUniqSets
 class UserOfLocalRegs a where
   foldRegsUsed :: (b -> LocalReg -> b) -> b -> a -> b
 
+filterRegsUsed :: UserOfLocalRegs e => (LocalReg -> Bool) -> e -> RegSet
+filterRegsUsed p e =
+    foldRegsUsed (\regs r -> if p r then extendRegSet regs r else regs)
+                 emptyRegSet e
+
 instance UserOfLocalRegs CmmReg where
     foldRegsUsed f z (CmmLocal reg) = f z reg
     foldRegsUsed _ z (CmmGlobal _)  = z