X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fmain%2FDynFlags.hs;h=f88d02c49a05edb480040cde033f13ac5e3ec47e;hp=d3019eef64840047bab4e7f0ae3098d5772e7539;hb=2412b0b38f23d645632a780d1659627ba398d947;hpb=bfd0c33d39619b580520e2d6e43d306380393ea6

diff --git a/compiler/main/DynFlags.hs b/compiler/main/DynFlags.hs
index d3019ee..f88d02c 100644
--- a/compiler/main/DynFlags.hs
+++ b/compiler/main/DynFlags.hs
@@ -1186,6 +1186,7 @@ dynamic_flags = [
 	------ Optimisation flags ------------------------------------------
   ,  ( "O"	, NoArg (upd (setOptLevel 1)))
   ,  ( "Onot"	, NoArg (upd (setOptLevel 0))) -- deprecated
+  ,  ( "Odph"   , NoArg (upd setDPHOpt))
   ,  ( "O"	, OptIntSuffix (\mb_n -> upd (setOptLevel (mb_n `orElse` 1))))
 		-- If the number is missing, use 1
 
@@ -1581,6 +1582,24 @@ setOptLevel n dflags
 	= updOptLevel n dflags
 
 
+-- -Odph is equivalent to
+--
+--    -O2                               optimise as much as possible
+--    -fno-method-sharing               sharing specialisation defeats fusion
+--                                      sometimes
+--    -fdicts-cheap                     always inline dictionaries
+--    -fmax-simplifier-iterations20     this is necessary sometimes
+--    -fno-spec-constr-threshold        run SpecConstr even for big loops
+--
+setDPHOpt :: DynFlags -> DynFlags
+setDPHOpt dflags = setOptLevel 2 (dflags { maxSimplIterations  = 20
+                                         , specConstrThreshold = Nothing
+                                         })
+                   `dopt_set`   Opt_DictsCheap
+                   `dopt_unset` Opt_MethodSharing
+
+
+
 setMainIs :: String -> DynP ()
 setMainIs arg
   | not (null main_fn) && isLower (head main_fn)