Hooked the C-- CPS pass into the compilation pipeline

At present it just annotates each block with a comment
indicating what local registers are live at the start
of the block.

compiler/cmm/CmmCPS.hs

+module CmmCPS (cmmCPS) where
+
+#include "HsVersions.h"
+
+import Cmm
+import CmmLint
+import PprCmm
+
+import Dataflow (mapCmmTop, onBasicBlock, cmmLivenessComment, cmmLiveness)
+
+import DynFlags
+import ErrUtils
+import Maybes
+import Outputable
+
+import Monad
+import IO
+
+cmmCPS :: DynFlags
+       -> [Cmm]                 -- C-- with Proceedures
+       -> IO [Cmm]		-- Output: CPS transformed C--
+
+cmmCPS dflags abstractC = do
+  when (dopt Opt_DoCmmLinting dflags) $
+       do showPass dflags "CmmLint"
+	  case firstJust $ map cmmLint abstractC of
+	    Just err -> do printDump err
+			   ghcExit dflags 1
+	    Nothing  -> return ()
+  showPass dflags "CPS"
+  -- continuationC <- return abstractC
+  continuationC <- return $ map (mapCmmTop (onBasicBlock (\bs -> map (cmmLivenessComment (cmmLiveness bs)) bs))) abstractC
+
+  dumpIfSet_dyn dflags Opt_D_dump_cps_cmm "CPS Cmm" (pprCmms continuationC)
+  -- TODO: add option to dump Cmm to file
+  return continuationC

compiler/main/DynFlags.hs

@@ -92,6 +92,7 @@ data DynFlag
 
    -- debugging flags
    = Opt_D_dump_cmm
+   | Opt_D_dump_cps_cmm
    | Opt_D_dump_asm
    | Opt_D_dump_cpranal
    | Opt_D_dump_deriv
@@ -937,6 +938,7 @@ dynamic_flags = [
   ,  ( "dstg-stats",	NoArg (setDynFlag Opt_StgStats))
 
   ,  ( "ddump-cmm",         	 setDumpFlag Opt_D_dump_cmm)
+  ,  ( "ddump-cps-cmm",        	 setDumpFlag Opt_D_dump_cps_cmm)
   ,  ( "ddump-asm",          	 setDumpFlag Opt_D_dump_asm)
   ,  ( "ddump-cpranal",      	 setDumpFlag Opt_D_dump_cpranal)
   ,  ( "ddump-deriv",        	 setDumpFlag Opt_D_dump_deriv)

compiler/main/HscMain.lhs

@@ -75,6 +75,7 @@ import Name		( Name, NamedThing(..) )
 import SimplStg		( stg2stg )
 import CodeGen		( codeGen )
 import CmmParse		( parseCmmFile )
+import CmmCPS
 import CodeOutput	( codeOutput )
 import NameEnv          ( emptyNameEnv )
 
@@ -603,10 +604,12 @@ hscCompile cgguts
                       codeGen dflags this_mod data_tycons
                               foreign_stubs dir_imps cost_centre_info
                               stg_binds hpc_info
+         ------------------  Convert to CPS --------------------
+         continuationC <- cmmCPS dflags abstractC
          ------------------  Code output -----------------------
          (stub_h_exists,stub_c_exists)
              <- codeOutput dflags this_mod location foreign_stubs 
-                dependencies abstractC
+                dependencies continuationC
          return stub_c_exists
 
 hscConst :: b -> a -> Comp b
@@ -718,7 +721,8 @@ hscCmmFile dflags filename = do
   case maybe_cmm of
     Nothing -> return False
     Just cmm -> do
-	codeOutput dflags no_mod no_loc NoStubs [] [cmm]
+        continuationC <- cmmCPS dflags [cmm]
+	codeOutput dflags no_mod no_loc NoStubs [] continuationC
 	return True
   where
 	no_mod = panic "hscCmmFile: no_mod"