Refactoring: explicitly mark whether we have an info table in RawCmm

I introduced this to support explicitly recording the info table label
in RawCmm for another patch I am working on, but it turned out to lead
to significant simplification in those parts of the compiler that
consume RawCmm.

Now, instead of lots of tests for null [CmmStatic] we have a simple
test of a Maybe, and have reduced the number of guys that need to know
how to convert entry->info labels by a TON. There are only 3 callers
of that function now!

3 files changed, 14 insertions, 15 deletions

diff --git a/compiler/llvmGen/LlvmCodeGen.hs b/compiler/llvmGen/LlvmCodeGen.hs
index 46f3f268a3..340a313561 100644
--- a/compiler/llvmGen/LlvmCodeGen.hs
+++ b/compiler/llvmGen/LlvmCodeGen.hs
@@ -13,7 +13,6 @@ import LlvmCodeGen.Data
 import LlvmCodeGen.Ppr
 import LlvmMangler
 
-import CLabel
 import CgUtils ( fixStgRegisters )
 import OldCmm
 import OldPprCmm
@@ -40,9 +39,9 @@ llvmCodeGen dflags h us cmms
         (cdata,env) = foldr split ([],initLlvmEnv) cmm
         split (CmmData s d' ) (d,e) = ((s,d'):d,e)
         split (CmmProc i l _) (d,e) =
-            let lbl = strCLabel_llvm $ if not (null i)
-                   then entryLblToInfoLbl l
-                   else l
+            let lbl = strCLabel_llvm $ case i of
+                        Nothing                   -> l
+                        Just (Statics info_lbl _) -> info_lbl
                 env' = funInsert lbl llvmFunTy e
             in (d,env')
     in do
diff --git a/compiler/llvmGen/LlvmCodeGen/Base.hs b/compiler/llvmGen/LlvmCodeGen/Base.hs
index e73f41cde1..1c7592ad2d 100644
--- a/compiler/llvmGen/LlvmCodeGen/Base.hs
+++ b/compiler/llvmGen/LlvmCodeGen/Base.hs
@@ -41,7 +41,7 @@ import Unique
 -- * Some Data Types
 --
 
-type LlvmCmmTop = GenCmmTop [LlvmData] [CmmStatic] (ListGraph LlvmStatement)
+type LlvmCmmTop = GenCmmTop [LlvmData] (Maybe CmmStatics) (ListGraph LlvmStatement)
 type LlvmBasicBlock = GenBasicBlock LlvmStatement
 
 -- | Unresolved code.
diff --git a/compiler/llvmGen/LlvmCodeGen/Ppr.hs b/compiler/llvmGen/LlvmCodeGen/Ppr.hs
index 48a0d6967c..40f7ce05f1 100644
--- a/compiler/llvmGen/LlvmCodeGen/Ppr.hs
+++ b/compiler/llvmGen/LlvmCodeGen/Ppr.hs
@@ -82,16 +82,16 @@ pprLlvmCmmTop :: LlvmEnv -> Int -> LlvmCmmTop -> (Doc, [LlvmVar])
 pprLlvmCmmTop _ _ (CmmData _ lmdata)
   = (vcat $ map pprLlvmData lmdata, [])
 
-pprLlvmCmmTop env count (CmmProc info lbl (ListGraph blks))
-  = let static = Statics lbl info
-        (idoc, ivar) = if not (null info)
-                          then pprInfoTable env count lbl static
-                          else (empty, [])
+pprLlvmCmmTop env count (CmmProc mb_info entry_lbl (ListGraph blks))
+  = let (idoc, ivar) = case mb_info of
+                        Nothing -> (empty, [])
+                        Just (Statics info_lbl dat)
+                         -> pprInfoTable env count info_lbl (Statics entry_lbl dat)
     in (idoc $+$ (
         let sec = mkLayoutSection (count + 1)
-            (lbl',sec') = if not (null info)
-                            then (entryLblToInfoLbl lbl, sec)
-                            else (lbl, Nothing)
+            (lbl',sec') = case mb_info of
+                           Nothing                   -> (entry_lbl, Nothing)
+                           Just (Statics info_lbl _) -> (info_lbl,  sec)
             link = if externallyVisibleCLabel lbl'
                       then ExternallyVisible
                       else Internal
@@ -104,13 +104,13 @@ pprLlvmCmmTop env count (CmmProc info lbl (ListGraph blks))
 
 -- | Pretty print CmmStatic
 pprInfoTable :: LlvmEnv -> Int -> CLabel -> CmmStatics -> (Doc, [LlvmVar])
-pprInfoTable env count lbl stat
+pprInfoTable env count info_lbl stat
   = let unres = genLlvmData (Text, stat)
         (_, (ldata, ltypes)) = resolveLlvmData env unres
 
         setSection ((LMGlobalVar _ ty l _ _ c), d)
             = let sec = mkLayoutSection count
-                  ilabel = strCLabel_llvm (entryLblToInfoLbl lbl)
+                  ilabel = strCLabel_llvm info_lbl
                               `appendFS` fsLit iTableSuf
                   gv = LMGlobalVar ilabel ty l sec llvmInfAlign c
                   v = if l == Internal then [gv] else []