From ef4734ebb671d9ef19c284a4c5cc9412d6e62874 Mon Sep 17 00:00:00 2001
From: Gregor Kleen <gregor.kleen@ifi.lmu.de>
Date: Wed, 21 Jul 2021 21:55:04 +0200
Subject: [PATCH] fix(arc): actually invalidate

---
 src/Utils/ARC.hs | 44 ++++++++++++++++++++++++++++----------------
 1 file changed, 28 insertions(+), 16 deletions(-)

diff --git a/src/Utils/ARC.hs b/src/Utils/ARC.hs
index 62726eb62..a5e2a8c76 100644
--- a/src/Utils/ARC.hs
+++ b/src/Utils/ARC.hs
@@ -146,23 +146,35 @@ arcAlterF !(force -> unhashedK@(hashed -> k)) f oldARC@ARC{..} now
   | later <= initialARCTick = uncurry (arcAlterF unhashedK f) $ initARC arcMaximumGhost arcMaximumWeight
   | otherwise = (, later) <$> if
     | Just (_p, x@(_, w), arcFrequent') <- HashPSQ.deleteView k arcFrequent
-      -> f (Just x) <&> \(fromMaybe x -> !(force -> x'@(_, w')))
-           -> let (arcFrequent'', arcFrequentWeight'', arcGhostFrequent') = evictToSize (arcMaximumWeight |- arcTargetRecent |- w') arcFrequent' (arcFrequentWeight - w) arcGhostFrequent
-               in oldARC
-                    { arcFrequent = HashPSQ.insert k now x' arcFrequent''
-                    , arcFrequentWeight = arcFrequentWeight'' + w'
-                    , arcGhostFrequent = arcGhostFrequent'
-                    }
+      -> f (Just x) <&> \case
+           Nothing -> oldARC
+             { arcFrequent = arcFrequent'
+             , arcGhostFrequent = HashPSQ.insert k now () arcGhostFrequent
+             , arcFrequentWeight = arcFrequentWeight - w
+             }
+           Just !(force -> x'@(_, w'))
+             -> let (arcFrequent'', arcFrequentWeight'', arcGhostFrequent') = evictToSize (arcMaximumWeight |- arcTargetRecent |- w') arcFrequent' (arcFrequentWeight - w) arcGhostFrequent
+                 in oldARC
+                      { arcFrequent = HashPSQ.insert k now x' arcFrequent''
+                      , arcFrequentWeight = arcFrequentWeight'' + w'
+                      , arcGhostFrequent = arcGhostFrequent'
+                      }
     | Just (_p, x@(_, w), arcRecent') <- HashPSQ.deleteView k arcRecent
-      -> f (Just x) <&> \(fromMaybe x -> !(force -> x'@(_, w')))
-           -> let (arcFrequent', arcFrequentWeight', arcGhostFrequent') = evictToSize (arcMaximumWeight |- arcTargetRecent |- w') arcFrequent arcFrequentWeight arcGhostFrequent
-               in oldARC
-                    { arcRecent = arcRecent'
-                    , arcRecentWeight = arcRecentWeight - w
-                    , arcFrequent = HashPSQ.insert k now x' arcFrequent'
-                    , arcFrequentWeight = arcFrequentWeight' + w'
-                    , arcGhostFrequent = arcGhostFrequent'
-                    }
+      -> f (Just x) <&> \case
+           Nothing -> oldARC
+             { arcRecent = arcRecent'
+             , arcGhostRecent = HashPSQ.insert k now () $ evictGhostToCount arcGhostRecent
+             , arcRecentWeight = arcRecentWeight - w
+             }
+           Just !(force -> x'@(_, w'))
+             -> let (arcFrequent', arcFrequentWeight', arcGhostFrequent') = evictToSize (arcMaximumWeight |- arcTargetRecent |- w') arcFrequent arcFrequentWeight arcGhostFrequent
+                 in oldARC
+                      { arcRecent = arcRecent'
+                      , arcRecentWeight = arcRecentWeight - w
+                      , arcFrequent = HashPSQ.insert k now x' arcFrequent'
+                      , arcFrequentWeight = arcFrequentWeight' + w'
+                      , arcGhostFrequent = arcGhostFrequent'
+                      }
     | Just (_p, (), arcGhostRecent') <- HashPSQ.deleteView k arcGhostRecent
       -> f Nothing <&> \case
            Nothing -> oldARC