[commit: ghc] master: Minor refactoring in CmmUtils.mkLiveness (3efd7cd)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3efd7cd9bacc362b97a5c8b23994addaa614adda/ghc

>---------------------------------------------------------------

commit 3efd7cd9bacc362b97a5c8b23994addaa614adda
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Thu Jul 12 17:09:52 2018 +0300

    Minor refactoring in CmmUtils.mkLiveness
    
    Test Plan: validate
    
    Reviewers: bgamari, simonmar
    
    Reviewed By: simonmar
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4957


>---------------------------------------------------------------

3efd7cd9bacc362b97a5c8b23994addaa614adda
 compiler/cmm/CmmParse.y  |  2 +-
 compiler/cmm/CmmUtils.hs | 19 ++++++++-----------
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/compiler/cmm/CmmParse.y b/compiler/cmm/CmmParse.y
index 4d7e288..8cc9883 100644
--- a/compiler/cmm/CmmParse.y
+++ b/compiler/cmm/CmmParse.y
@@ -542,7 +542,7 @@ info    :: { CmmParse (CLabel, Maybe CmmInfoTable, [LocalReg]) }
                       live <- sequence $7
                       let prof = NoProfilingInfo
                           -- drop one for the info pointer
-                          bitmap = mkLiveness dflags (map Just (drop 1 live))
+                          bitmap = mkLiveness dflags (drop 1 live)
                           rep  = mkRTSRep (fromIntegral $5) $ mkStackRep bitmap
                       return (mkCmmRetLabel pkg $3,
                               Just $ CmmInfoTable { cit_lbl = mkCmmRetInfoLabel pkg $3
diff --git a/compiler/cmm/CmmUtils.hs b/compiler/cmm/CmmUtils.hs
index 1ae5526..42d6484 100644
--- a/compiler/cmm/CmmUtils.hs
+++ b/compiler/cmm/CmmUtils.hs
@@ -456,20 +456,17 @@ regUsedIn dflags = regUsedIn_ where
 --
 ---------------------------------------------
 
-mkLiveness :: DynFlags -> [Maybe LocalReg] -> Liveness
+mkLiveness :: DynFlags -> [LocalReg] -> Liveness
 mkLiveness _      [] = []
 mkLiveness dflags (reg:regs)
-  = take sizeW bits ++ mkLiveness dflags regs
+  = bits ++ mkLiveness dflags regs
   where
-    sizeW = case reg of
-              Nothing -> 1
-              Just r -> (widthInBytes (typeWidth (localRegType r)) + wORD_SIZE dflags - 1)
-                        `quot` wORD_SIZE dflags
-                        -- number of words, rounded up
-    bits = repeat $ is_non_ptr reg -- True <=> Non Ptr
-
-    is_non_ptr Nothing    = True
-    is_non_ptr (Just reg) = not $ isGcPtrType (localRegType reg)
+    sizeW = (widthInBytes (typeWidth (localRegType reg)) + wORD_SIZE dflags - 1)
+            `quot` wORD_SIZE dflags
+            -- number of words, rounded up
+    bits = replicate sizeW is_non_ptr -- True <=> Non Ptr
+
+    is_non_ptr = not $ isGcPtrType (localRegType reg)
 
 
 -- ============================================== -