Put CFG weights into their own module (#17957)

It avoids having to query DynFlags to get them

1 files changed, 5 insertions, 76 deletions

diff --git a/compiler/GHC/Driver/Session.hs b/compiler/GHC/Driver/Session.hs
index fea01278ef..40ccb400bc 100644
--- a/compiler/GHC/Driver/Session.hs
+++ b/compiler/GHC/Driver/Session.hs
@@ -226,9 +226,6 @@ module GHC.Driver.Session (
 
         -- * SDoc
         initSDocContext, initDefaultSDocContext,
-
-        -- * Make use of the Cmm CFG
-        CfgWeights(..)
   ) where
 
 #include "HsVersions.h"
@@ -268,6 +265,7 @@ import GHC.Data.FastString
 import GHC.Utils.Fingerprint
 import GHC.Utils.Outputable
 import GHC.Settings
+import GHC.CmmToAsm.CFG.Weight
 
 import {-# SOURCE #-} GHC.Utils.Error
                                ( Severity(..), MsgDoc, mkLocMessageAnn
@@ -777,78 +775,9 @@ data DynFlags = DynFlags {
   uniqueIncrement       :: Int,
 
   -- | Temporary: CFG Edge weights for fast iterations
-  cfgWeightInfo         :: CfgWeights
+  cfgWeights            :: Weights
 }
 
--- | Edge weights to use when generating a CFG from CMM
-data CfgWeights
-    = CFGWeights
-    { uncondWeight :: Int
-    , condBranchWeight :: Int
-    , switchWeight :: Int
-    , callWeight :: Int
-    , likelyCondWeight :: Int
-    , unlikelyCondWeight :: Int
-    , infoTablePenalty :: Int
-    , backEdgeBonus :: Int
-    }
-
-defaultCfgWeights :: CfgWeights
-defaultCfgWeights
-    = CFGWeights
-    { uncondWeight = 1000
-    , condBranchWeight = 800
-    , switchWeight = 1
-    , callWeight = -10
-    , likelyCondWeight = 900
-    , unlikelyCondWeight = 300
-    , infoTablePenalty = 300
-    , backEdgeBonus = 400
-    }
-
-parseCfgWeights :: String -> CfgWeights -> CfgWeights
-parseCfgWeights s oldWeights =
-        foldl' (\cfg (n,v) -> update n v cfg) oldWeights assignments
-    where
-        assignments = map assignment $ settings s
-        update "uncondWeight" n w =
-            w {uncondWeight = n}
-        update "condBranchWeight" n w =
-            w {condBranchWeight = n}
-        update "switchWeight" n w =
-            w {switchWeight = n}
-        update "callWeight" n w =
-            w {callWeight = n}
-        update "likelyCondWeight" n w =
-            w {likelyCondWeight = n}
-        update "unlikelyCondWeight" n w =
-            w {unlikelyCondWeight = n}
-        update "infoTablePenalty" n w =
-            w {infoTablePenalty = n}
-        update "backEdgeBonus" n w =
-            w {backEdgeBonus = n}
-        update other _ _
-            = panic $ other ++
-                      " is not a cfg weight parameter. " ++
-                      exampleString
-        settings s
-            | (s1,rest) <- break (== ',') s
-            , null rest
-            = [s1]
-            | (s1,rest) <- break (== ',') s
-            = s1 : settings (drop 1 rest)
-
-        assignment as
-            | (name, _:val) <- break (== '=') as
-            = (name,read val)
-            | otherwise
-            = panic $ "Invalid cfg parameters." ++ exampleString
-
-        exampleString = "Example parameters: uncondWeight=1000," ++
-            "condBranchWeight=800,switchWeight=0,callWeight=300" ++
-            ",likelyCondWeight=900,unlikelyCondWeight=300" ++
-            ",infoTablePenalty=300,backEdgeBonus=400"
-
 class HasDynFlags m where
     getDynFlags :: m DynFlags
 
@@ -1430,7 +1359,7 @@ defaultDynFlags mySettings llvmConfig =
 
         reverseErrors = False,
         maxErrors     = Nothing,
-        cfgWeightInfo = defaultCfgWeights
+        cfgWeights    = defaultWeights
       }
 
 defaultWays :: Settings -> Ways
@@ -2949,8 +2878,8 @@ dynamic_flags_deps = [
       (intSuffix (\n d -> d { cmmProcAlignment = Just n }))
   , make_ord_flag defFlag "fblock-layout-weights"
         (HasArg (\s ->
-            upd (\d -> d { cfgWeightInfo =
-                parseCfgWeights s (cfgWeightInfo d)})))
+            upd (\d -> d { cfgWeights =
+                parseWeights s (cfgWeights d)})))
   , make_ord_flag defFlag "fhistory-size"
       (intSuffix (\n d -> d { historySize = n }))
   , make_ord_flag defFlag "funfolding-creation-threshold"