Set -fproc-alignment=64 for benchmarks (#577)

* Set -fproc-alignment=64 for benchmarks * Benchmarks: force absurdlong before actual benchmarking
haskell · Feb 16, 2023 · da6ea8f · da6ea8f
1 parent 0bd68ca
commit da6ea8f
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Showing 3 changed files with 8 additions and 6 deletions.
diff --git a/bench/BenchIndices.hs b/bench/BenchIndices.hs
@@ -38,15 +38,15 @@ nilEq = (==)
 
 -- lines of 200 letters from a to e, followed by repeated letter f
 absurdlong :: S.ByteString
-absurdlong = S.replicate 200 0x61 <> S.singleton nl
+absurdlong = (S.replicate 200 0x61 <> S.singleton nl
           <> S.replicate 200 0x62 <> S.singleton nl
           <> S.replicate 200 0x63 <> S.singleton nl
           <> S.replicate 200 0x64 <> S.singleton nl
-          <> S.replicate 200 0x65 <> S.singleton nl
+          <> S.replicate 200 0x65 <> S.singleton nl)
           <> S.replicate 999999 0x66
 
 benchIndices :: Benchmark
-benchIndices = bgroup "Indices"
+benchIndices = absurdlong `seq` bgroup "Indices"
     [ bgroup "ByteString strict first index" $
         [ bench "FindIndices" $ nf (listToMaybe . S.findIndices (== nl)) absurdlong
         , bench "ElemIndices" $ nf (listToMaybe . S.elemIndices     nl)  absurdlong

diff --git a/bench/BenchShort.hs b/bench/BenchShort.hs
@@ -138,11 +138,11 @@ nilEq = (==)
 
 -- lines of 200 letters from a to e, followed by repeated letter f
 absurdlong :: S.ShortByteString
-absurdlong = S.replicate 200 0x61 <> S.singleton nl
+absurdlong = (S.replicate 200 0x61 <> S.singleton nl
           <> S.replicate 200 0x62 <> S.singleton nl
           <> S.replicate 200 0x63 <> S.singleton nl
           <> S.replicate 200 0x64 <> S.singleton nl
-          <> S.replicate 200 0x65 <> S.singleton nl
+          <> S.replicate 200 0x65 <> S.singleton nl)
           <> S.replicate 999999 0x66
 
 bench_find_index_second :: ShortByteString -> Maybe Int
@@ -166,7 +166,7 @@ bench_elem_index_second bs =
 -------------
 
 benchShort :: Benchmark
-benchShort = bgroup "ShortByteString"
+benchShort = absurdlong `seq` bgroup "ShortByteString"
     [ bgroup "Small payload"
       [ benchB' "mempty"        ()  (const mempty)
       , benchB' "UTF-8 String (naive)" "hello world\0" fromString

diff --git a/bytestring.cabal b/bytestring.cabal
@@ -194,6 +194,8 @@ benchmark bytestring-bench
   hs-source-dirs:   bench
   default-language: Haskell2010
   ghc-options:      -O2 "-with-rtsopts=-A32m"
+  if impl(ghc >= 8.6)
+    ghc-options:    -fproc-alignment=64
   build-depends:    base,
                     bytestring,
                     deepseq,