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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/hsSyn/HsUtils.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/hsSyn/HsUtils.hs')
| -rw-r--r-- | compiler/hsSyn/HsUtils.hs | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/compiler/hsSyn/HsUtils.hs b/compiler/hsSyn/HsUtils.hs index eba21cf1e2..c3537266e3 100644 --- a/compiler/hsSyn/HsUtils.hs +++ b/compiler/hsSyn/HsUtils.hs @@ -184,7 +184,7 @@ mkHsAppType e t = addCLoc e t_body (HsAppType paren_wct e) paren_wct = t { hswc_body = parenthesizeHsType appPrec t_body } mkHsAppTypes :: LHsExpr GhcRn -> [LHsWcType GhcRn] -> LHsExpr GhcRn -mkHsAppTypes = foldl mkHsAppType +mkHsAppTypes = foldl' mkHsAppType mkHsLam :: [LPat GhcPs] -> LHsExpr GhcPs -> LHsExpr GhcPs mkHsLam pats body = mkHsPar (L (getLoc body) (HsLam noExt matches)) @@ -210,7 +210,7 @@ nlHsTyApp fun_id tys nlHsTyApps :: IdP (GhcPass id) -> [Type] -> [LHsExpr (GhcPass id)] -> LHsExpr (GhcPass id) -nlHsTyApps fun_id tys xs = foldl nlHsApp (nlHsTyApp fun_id tys) xs +nlHsTyApps fun_id tys xs = foldl' nlHsApp (nlHsTyApp fun_id tys) xs --------- Adding parens --------- mkLHsPar :: LHsExpr (GhcPass id) -> LHsExpr (GhcPass id) @@ -418,17 +418,17 @@ nlHsSyntaxApps (SyntaxExpr { syn_expr = fun , syn_res_wrap = res_wrap }) args | [] <- arg_wraps -- in the noSyntaxExpr case = ASSERT( isIdHsWrapper res_wrap ) - foldl nlHsApp (noLoc fun) args + foldl' nlHsApp (noLoc fun) args | otherwise - = mkLHsWrap res_wrap (foldl nlHsApp (noLoc fun) (zipWithEqual "nlHsSyntaxApps" + = mkLHsWrap res_wrap (foldl' nlHsApp (noLoc fun) (zipWithEqual "nlHsSyntaxApps" mkLHsWrap arg_wraps args)) nlHsApps :: IdP (GhcPass id) -> [LHsExpr (GhcPass id)] -> LHsExpr (GhcPass id) -nlHsApps f xs = foldl nlHsApp (nlHsVar f) xs +nlHsApps f xs = foldl' nlHsApp (nlHsVar f) xs nlHsVarApps :: IdP (GhcPass id) -> [IdP (GhcPass id)] -> LHsExpr (GhcPass id) -nlHsVarApps f xs = noLoc (foldl mk (HsVar noExt (noLoc f)) +nlHsVarApps f xs = noLoc (foldl' mk (HsVar noExt (noLoc f)) (map ((HsVar noExt) . noLoc) xs)) where mk f a = HsApp noExt (noLoc f) (noLoc a) @@ -510,7 +510,7 @@ nlHsFunTy a b = noLoc (HsFunTy noExt (parenthesizeHsType funPrec a) nlHsParTy t = noLoc (HsParTy noExt t) nlHsTyConApp :: IdP (GhcPass p) -> [LHsType (GhcPass p)] -> LHsType (GhcPass p) -nlHsTyConApp tycon tys = foldl nlHsAppTy (nlHsTyVar tycon) tys +nlHsTyConApp tycon tys = foldl' nlHsAppTy (nlHsTyVar tycon) tys {- Tuples. All these functions are *pre-typechecker* because they lack |