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author | Michal Terepeta <michal.terepeta@gmail.com> | 2018-02-18 11:09:40 -0500 |
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committer | Ben Gamari <ben@smart-cactus.org> | 2018-02-18 11:57:45 -0500 |
commit | 4e513bf758c32804fc71b98215f96e8481697a36 (patch) | |
tree | 5931931d59e1299dfae6c0e656c84cd50558e970 /compiler/cmm | |
parent | c05529c2219d12ee950eb8972e1aca135cd8e032 (diff) | |
download | haskell-4e513bf758c32804fc71b98215f96e8481697a36.tar.gz |
CBE: re-introduce bgamari's fixes
During some recent work on CBE we discovered that `zipWith` is used to
check for equality, but that doesn't quite work if lists are of
different lengths! This was fixed by bgamari, but unfortunately the fix
had to be rolled back due to other changes in CBE in
50adbd7c5fe5894d3e6e2a58b353ed07e5f8949d. Since I wanted to have another
look at CBE anyway, we agreed that the first thing to do would be to
re-introduce the fix.
Sadly I don't have any actual test case that would exercise this.
Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>
Test Plan: ./validate
Reviewers: bgamari, simonmar
Reviewed By: bgamari
Subscribers: rwbarton, thomie, carter
GHC Trac Issues: #14226
Differential Revision: https://phabricator.haskell.org/D4387
Diffstat (limited to 'compiler/cmm')
-rw-r--r-- | compiler/cmm/CmmCommonBlockElim.hs | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/compiler/cmm/CmmCommonBlockElim.hs b/compiler/cmm/CmmCommonBlockElim.hs index 2c889b382a..ba3b1c8a53 100644 --- a/compiler/cmm/CmmCommonBlockElim.hs +++ b/compiler/cmm/CmmCommonBlockElim.hs @@ -209,7 +209,7 @@ eqMiddleWith eqBid (CmmStore l1 r1) (CmmStore l2 r2) = eqExprWith eqBid l1 l2 && eqExprWith eqBid r1 r2 eqMiddleWith eqBid (CmmUnsafeForeignCall t1 r1 a1) (CmmUnsafeForeignCall t2 r2 a2) - = t1 == t2 && r1 == r2 && and (zipWith (eqExprWith eqBid) a1 a2) + = t1 == t2 && r1 == r2 && eqListWith (eqExprWith eqBid) a1 a2 eqMiddleWith _ _ _ = False eqExprWith :: (BlockId -> BlockId -> Bool) @@ -224,7 +224,7 @@ eqExprWith eqBid = eq CmmStackSlot a1 i1 `eq` CmmStackSlot a2 i2 = eqArea a1 a2 && i1==i2 _e1 `eq` _e2 = False - xs `eqs` ys = and (zipWith eq xs ys) + xs `eqs` ys = eqListWith eq xs ys eqLit (CmmBlock id1) (CmmBlock id2) = eqBid id1 id2 eqLit l1 l2 = l1 == l2 @@ -247,7 +247,7 @@ eqBlockBodyWith eqBid block block' (_,m',l') = blockSplit block' nodes' = filter (not . dont_care) (blockToList m') - equal = and (zipWith (eqMiddleWith eqBid) nodes nodes') && + equal = eqListWith (eqMiddleWith eqBid) nodes nodes' && eqLastWith eqBid l l' @@ -266,6 +266,11 @@ eqMaybeWith eltEq (Just e) (Just e') = eltEq e e' eqMaybeWith _ Nothing Nothing = True eqMaybeWith _ _ _ = False +eqListWith :: (a -> b -> Bool) -> [a] -> [b] -> Bool +eqListWith f (a : as) (b : bs) = f a b && eqListWith f as bs +eqListWith _ [] [] = True +eqListWith _ _ _ = False + -- | Given a block map, ensure that all "target" blocks are covered by -- the same ticks as the respective "source" blocks. This not only -- means copying ticks, but also adjusting tick scopes where |