Some infrastruture for lambda-lifting

[ghc-hetmet.git] / compiler / main / DynFlags.hs

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index fa92d57..116ff32 100644 (file)
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -199,6 +199,7 @@ data DynFlag
    | Opt_WarnDodgyImports
    | Opt_WarnOrphans
    | Opt_WarnAutoOrphans
+   | Opt_WarnIdentities
    | Opt_WarnTabs
    | Opt_WarnUnrecognisedPragmas
    | Opt_WarnDodgyForeignImports
@@ -223,7 +224,7 @@ data DynFlag
    | Opt_DoEtaReduction
    | Opt_CaseMerge
    | Opt_UnboxStrictFields
-   | Opt_MethodSharing
+   | Opt_MethodSharing -- Now a no-op; remove in GHC 7.2
    | Opt_DictsCheap
    | Opt_EnableRewriteRules            -- Apply rewrite rules during simplification
    | Opt_Vectorise
@@ -381,6 +382,8 @@ data DynFlags = DynFlags {
   specConstrThreshold   :: Maybe Int,   -- ^ Threshold for SpecConstr
   specConstrCount       :: Maybe Int,   -- ^ Max number of specialisations for any one function
   liberateCaseThreshold :: Maybe Int,   -- ^ Threshold for LiberateCase
+  floatLamArgs          :: Maybe Int,   -- ^ Arg count for lambda floating
+                                       --   See CoreMonad.FloatOutSwitches
 
 #ifndef OMIT_NATIVE_CODEGEN
   targetPlatform       :: Platform,    -- ^ The platform we're compiling for. Used by the NCG.
@@ -649,6 +652,7 @@ defaultDynFlags =
         specConstrThreshold     = Just 200,
         specConstrCount         = Just 3,
         liberateCaseThreshold   = Just 200,
+        floatLamArgs            = Just 0,      -- Default: float only if no fvs
         strictnessBefore        = [],
 
 #ifndef OMIT_NATIVE_CODEGEN
@@ -781,7 +785,9 @@ flattenExtensionFlags ml = foldr f defaultExtensionFlags
           defaultExtensionFlags = languageExtensions ml
 
 languageExtensions :: Maybe Language -> [ExtensionFlag]
+
 languageExtensions Nothing
+    -- Nothing => the default case
     = Opt_MonoPatBinds   -- Experimentally, I'm making this non-standard
                          -- behaviour the default, to see if anyone notices
                          -- SLPJ July 06
@@ -789,11 +795,13 @@ languageExtensions Nothing
       -- But NB it's implied by GADTs etc
       -- SLPJ September 2010
     : languageExtensions (Just Haskell2010)
+
 languageExtensions (Just Haskell98)
     = [Opt_ImplicitPrelude,
        Opt_MonomorphismRestriction,
        Opt_NPlusKPatterns,
        Opt_DatatypeContexts]
+
 languageExtensions (Just Haskell2010)
     = [Opt_ImplicitPrelude,
        Opt_MonomorphismRestriction,
@@ -1298,6 +1306,8 @@ dynamic_flags = [
   , Flag "frule-check"                 (SepArg (\s -> upd (\d -> d{ ruleCheck = Just s })))
   , Flag "fcontext-stack"              (intSuffix (\n d -> d{ ctxtStkDepth = n }))
   , Flag "fstrictness-before"          (intSuffix (\n d -> d{ strictnessBefore = n : strictnessBefore d }))
+  , Flag "ffloat-lam-args"             (intSuffix (\n d -> d{ floatLamArgs = Just n }))
+  , Flag "ffloat-all-lams"             (intSuffix (\n d -> d{ floatLamArgs = Nothing }))
 
         ------ Profiling ----------------------------------------------------
 
@@ -1418,6 +1428,7 @@ fFlags = [
   ( "warn-deprecations",                Opt_WarnWarningsDeprecations, nop ),
   ( "warn-deprecated-flags",            Opt_WarnDeprecatedFlags, nop ),
   ( "warn-orphans",                     Opt_WarnOrphans, nop ),
+  ( "warn-identities",                  Opt_WarnIdentities, nop ),
   ( "warn-auto-orphans",                Opt_WarnAutoOrphans, nop ),
   ( "warn-tabs",                        Opt_WarnTabs, nop ),
   ( "warn-unrecognised-pragmas",        Opt_WarnUnrecognisedPragmas, nop ),
@@ -1442,7 +1453,9 @@ fFlags = [
   ( "do-eta-reduction",                 Opt_DoEtaReduction, nop ),
   ( "case-merge",                       Opt_CaseMerge, nop ),
   ( "unbox-strict-fields",              Opt_UnboxStrictFields, nop ),
-  ( "method-sharing",                   Opt_MethodSharing, nop ),
+  ( "method-sharing",                   Opt_MethodSharing, 
+     \_ -> deprecate "doesn't do anything any more"),
+     -- Remove altogether in GHC 7.2
   ( "dicts-cheap",                      Opt_DictsCheap, nop ),
   ( "excess-precision",                 Opt_ExcessPrecision, nop ),
   ( "eager-blackholing",                Opt_EagerBlackHoling, nop ),
@@ -1614,8 +1627,6 @@ defaultFlags
   = [ Opt_AutoLinkPackages,
       Opt_ReadUserPackageConf,
 
-      Opt_MethodSharing,
-
       Opt_DoAsmMangling,
 
       Opt_SharedImplib,
@@ -1731,7 +1742,8 @@ minusWallOpts
         Opt_WarnMissingSigs,
         Opt_WarnHiShadows,
         Opt_WarnOrphans,
-        Opt_WarnUnusedDoBind
+        Opt_WarnUnusedDoBind,
+        Opt_WarnIdentities
       ]
 
 -- minuswRemovesOpts should be every warning option
@@ -1965,7 +1977,6 @@ setDPHOpt dflags = setOptLevel 2 (dflags { maxSimplIterations  = 20
                                          , specConstrCount     = Nothing
                                          })
                    `dopt_set`   Opt_DictsCheap
-                   `dopt_unset` Opt_MethodSharing
 
 data DPHBackend = DPHPar
                 | DPHSeq