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| author | klebinger.andreas@gmx.at <klebinger.andreas@gmx.at> | 2018-08-21 12:10:38 -0400 |
|---|---|---|
| committer | Ben Gamari <ben@smart-cactus.org> | 2018-08-21 18:52:42 -0400 |
| commit | 09c1d5afba655a2427a448a9933bebe7d13b696b (patch) | |
| tree | d23083a9e99afe785f632e89f0186af8b191aee2 /compiler/main/Packages.hs | |
| parent | 02518f9d99c2d038384263f9e039efcb09bc96ff (diff) | |
| download | haskell-09c1d5afba655a2427a448a9933bebe7d13b696b.tar.gz | |
Replace most occurences of foldl with foldl'.
This patch adds foldl' to GhcPrelude and changes must occurences
of foldl to foldl'. This leads to better performance especially
for quick builds where GHC does not perform strictness analysis.
It does change strictness behaviour when we use foldl' to turn
a argument list into function applications. But this is only a
drawback if code looks ONLY at the last argument but not at the first.
And as the benchmarks show leads to fewer allocations in practice
at O2.
Compiler performance for Nofib:
O2 Allocations:
-1 s.d. ----- -0.0%
+1 s.d. ----- -0.0%
Average ----- -0.0%
O2 Compile Time:
-1 s.d. ----- -2.8%
+1 s.d. ----- +1.3%
Average ----- -0.8%
O0 Allocations:
-1 s.d. ----- -0.2%
+1 s.d. ----- -0.1%
Average ----- -0.2%
Test Plan: ci
Reviewers: goldfire, bgamari, simonmar, tdammers, monoidal
Reviewed By: bgamari, monoidal
Subscribers: tdammers, rwbarton, thomie, carter
Differential Revision: https://phabricator.haskell.org/D4929
Diffstat (limited to 'compiler/main/Packages.hs')
| -rw-r--r-- | compiler/main/Packages.hs | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/compiler/main/Packages.hs b/compiler/main/Packages.hs index 71354b1463..68940a7290 100644 --- a/compiler/main/Packages.hs +++ b/compiler/main/Packages.hs @@ -417,7 +417,7 @@ searchPackageId dflags pid = filter ((pid ==) . sourcePackageId) extendPackageConfigMap :: PackageConfigMap -> [PackageConfig] -> PackageConfigMap extendPackageConfigMap (PackageConfigMap pkg_map closure) new_pkgs - = PackageConfigMap (foldl add pkg_map new_pkgs) closure + = PackageConfigMap (foldl' add pkg_map new_pkgs) closure -- We also add the expanded version of the packageConfigId, so that -- 'improveUnitId' can find it. where add pkg_map p = addToUDFM (addToUDFM pkg_map (expandedPackageConfigId p) p) @@ -1519,7 +1519,7 @@ mkPackageState dflags dbs preload0 = do -- let preload1 = Map.keys (Map.filter uv_explicit vis_map) - let pkgname_map = foldl add Map.empty pkgs2 + let pkgname_map = foldl' add Map.empty pkgs2 where add pn_map p = Map.insert (packageName p) (componentId p) pn_map |