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

[ghc-hetmet.git] / compiler / cmm / CmmLint.hs

diff --git a/compiler/cmm/CmmLint.hs b/compiler/cmm/CmmLint.hs
index 80ad9ef..c2ef7e7 100644 (file)
--- a/compiler/cmm/CmmLint.hs
+++ b/compiler/cmm/CmmLint.hs
@@ -1,3 +1,10 @@
+{-# 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
+
 -----------------------------------------------------------------------------
 --
 -- (c) The University of Glasgow 2004-2006
@@ -25,10 +32,10 @@ import Control.Monad
 -- -----------------------------------------------------------------------------
 -- Exported entry points:
 
-cmmLint :: Cmm -> Maybe SDoc
+cmmLint :: GenCmm d h CmmStmt -> Maybe SDoc
 cmmLint (Cmm tops) = runCmmLint $ mapM_ lintCmmTop tops
 
-cmmLintTop :: CmmTop -> Maybe SDoc
+cmmLintTop :: GenCmmTop d h CmmStmt -> Maybe SDoc
 cmmLintTop top = runCmmLint $ lintCmmTop top
 
 runCmmLint :: CmmLint a -> Maybe SDoc
@@ -37,7 +44,7 @@ runCmmLint l =
        Left err -> Just (ptext SLIT("Cmm lint error:") $$ nest 2 err)
        Right _  -> Nothing
 
-lintCmmTop (CmmProc _info lbl _args blocks)
+lintCmmTop (CmmProc _ lbl _ blocks)
   = addLintInfo (text "in proc " <> pprCLabel lbl) $
        mapM_ lintCmmBlock blocks
 lintCmmTop _other
@@ -63,7 +70,7 @@ lintCmmExpr expr@(CmmMachOp op args) = do
   mapM_ lintCmmExpr args
   if map cmmExprRep args == machOpArgReps op
        then cmmCheckMachOp op args
-       else cmmLintMachOpErr expr
+       else cmmLintMachOpErr expr (map cmmExprRep args) (machOpArgReps op)
 lintCmmExpr (CmmRegOff reg offset)
   = lintCmmExpr (CmmMachOp (MO_Add rep) 
                [CmmReg reg, CmmLit (CmmInt (fromIntegral offset) rep)])
@@ -88,7 +95,8 @@ cmmCheckMachOp op args
   = return (resultRepOfMachOp op)
 
 isWordOffsetReg (CmmGlobal Sp) = True
-isWordOffsetReg (CmmGlobal Hp) = True
+-- No warnings for unaligned arithmetic, which is used to tag dynamic constructor closures.
+--isWordOffsetReg (CmmGlobal Hp) = True
 isWordOffsetReg _ = False
 
 isOffsetOp (MO_Add _) = True
@@ -98,14 +106,18 @@ isOffsetOp _ = False
 -- This expression should be an address from which a word can be loaded:
 -- check for funny-looking sub-word offsets.
 cmmCheckWordAddress e@(CmmMachOp op [arg, CmmLit (CmmInt i _)])
-  | isOffsetOp op && i `rem` fromIntegral wORD_SIZE /= 0
+  | isOffsetOp op && notNodeReg arg && i `rem` fromIntegral wORD_SIZE /= 0
   = cmmLintDubiousWordOffset e
 cmmCheckWordAddress e@(CmmMachOp op [CmmLit (CmmInt i _), arg])
-  | isOffsetOp op && i `rem` fromIntegral wORD_SIZE /= 0
+  | isOffsetOp op && notNodeReg arg && i `rem` fromIntegral wORD_SIZE /= 0
   = cmmLintDubiousWordOffset e
 cmmCheckWordAddress _
   = return ()
 
+-- No warnings for unaligned arithmetic with the node register,
+-- which is used to extract fields from tagged constructor closures.
+notNodeReg (CmmReg reg) | reg == nodeReg = False
+notNodeReg _                             = True
 
 lintCmmStmt :: CmmStmt -> CmmLint ()
 lintCmmStmt stmt@(CmmAssign reg expr) = do
@@ -117,9 +129,13 @@ lintCmmStmt (CmmStore l r) = do
   lintCmmExpr l
   lintCmmExpr r
   return ()
-lintCmmStmt (CmmCall _target _res args _vols) = mapM_ (lintCmmExpr.fst) args
+lintCmmStmt (CmmCall _target _res args _ _) = mapM_ (lintCmmExpr.fst) args
 lintCmmStmt (CmmCondBranch e _id)   = lintCmmExpr e >> checkCond e >> return ()
-lintCmmStmt (CmmSwitch e _branches) = lintCmmExpr e >> return ()
+lintCmmStmt (CmmSwitch e _branches) = do
+  erep <- lintCmmExpr e
+  if (erep == wordRep)
+    then return ()
+    else cmmLintErr (text "switch scrutinee is not a word: " <> ppr e)
 lintCmmStmt (CmmJump e _args)       = lintCmmExpr e >> return ()
 lintCmmStmt _other                 = return ()
 
@@ -149,9 +165,12 @@ addLintInfo info thing = CmmLint $
        Left err -> Left (hang info 2 err)
        Right a  -> Right a
 
-cmmLintMachOpErr :: CmmExpr -> CmmLint a
-cmmLintMachOpErr expr = cmmLintErr (text "in MachOp application: " $$ 
-                                       nest 2 (pprExpr expr))
+cmmLintMachOpErr :: CmmExpr -> [MachRep] -> [MachRep] -> CmmLint a
+cmmLintMachOpErr expr argsRep opExpectsRep
+     = cmmLintErr (text "in MachOp application: " $$ 
+                                       nest 2 (pprExpr expr) $$
+                                       (text "op is expecting: " <+> ppr opExpectsRep) $$
+                                       (text "arguments provide: " <+> ppr argsRep))
 
 cmmLintAssignErr :: CmmStmt -> CmmLint a
 cmmLintAssignErr stmt = cmmLintErr (text "in assignment: " $$