From b6809608cc467925db44b1eb435095c37e433255 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Sun, 5 Oct 2014 01:04:58 +0200 Subject: [PATCH] Get rid of some unnecessary ExprConcatStrings nodes in dynamic attrs This gives a ~18% speedup in NixOS evaluation (after converting most calls to hasAttr/getAttr to dynamic attrs). --- src/libexpr/eval.cc | 9 +++------ src/libexpr/nixexpr.hh | 14 +++++++------- src/libexpr/parser.y | 20 ++++++++------------ 3 files changed, 18 insertions(+), 25 deletions(-) diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index 1eeb80989..5122bd145 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -701,13 +701,10 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v) /* Dynamic attrs apply *after* rec and __overrides. */ foreach (DynamicAttrDefs::iterator, i, dynamicAttrs) { Value nameVal; - if (i->nameExpr->es->size() == 1) { - i->nameExpr->es->front()->eval(state, *dynamicEnv, nameVal); - state.forceValue(nameVal); - if (nameVal.type == tNull) - continue; - } i->nameExpr->eval(state, *dynamicEnv, nameVal); + state.forceValue(nameVal); + if (nameVal.type == tNull) + continue; state.forceStringNoCtx(nameVal); Symbol nameSym = state.symbols.create(nameVal.string.s); Bindings::iterator j = v.attrs->find(nameSym); diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh index 2619a7026..0eaa362fd 100644 --- a/src/libexpr/nixexpr.hh +++ b/src/libexpr/nixexpr.hh @@ -53,16 +53,15 @@ struct Env; struct Value; class EvalState; struct StaticEnv; -struct ExprConcatStrings; /* An attribute path is a sequence of attribute names. */ struct AttrName { Symbol symbol; - ExprConcatStrings * expr; + Expr * expr; AttrName(const Symbol & s) : symbol(s) {}; - AttrName(ExprConcatStrings * e) : expr(e) {}; + AttrName(Expr * e) : expr(e) {}; }; typedef std::vector AttrPath; @@ -173,16 +172,17 @@ struct ExprAttrs : Expr Expr * e; Pos pos; unsigned int displ; // displacement - AttrDef(Expr * e, const Pos & pos, bool inherited=false) : inherited(inherited), e(e), pos(pos) { }; + AttrDef(Expr * e, const Pos & pos, bool inherited=false) + : inherited(inherited), e(e), pos(pos) { }; AttrDef() { }; }; typedef std::map AttrDefs; AttrDefs attrs; struct DynamicAttrDef { - ExprConcatStrings * nameExpr; - Expr * valueExpr; + Expr * nameExpr, * valueExpr; Pos pos; - DynamicAttrDef(ExprConcatStrings * nameExpr, Expr * valueExpr, const Pos & pos) : nameExpr(nameExpr), valueExpr(valueExpr), pos(pos) { }; + DynamicAttrDef(Expr * nameExpr, Expr * valueExpr, const Pos & pos) + : nameExpr(nameExpr), valueExpr(valueExpr), pos(pos) { }; }; typedef std::vector DynamicAttrDefs; DynamicAttrDefs dynamicAttrs; diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y index 60a87ca94..dcb270b86 100644 --- a/src/libexpr/parser.y +++ b/src/libexpr/parser.y @@ -341,11 +341,7 @@ expr_op | expr_op UPDATE expr_op { $$ = new ExprOpUpdate(CUR_POS, $1, $3); } | expr_op '?' attrpath { $$ = new ExprOpHasAttr($1, *$3); } | expr_op '+' expr_op - { vector * l = new vector; - l->push_back($1); - l->push_back($3); - $$ = new ExprConcatStrings(CUR_POS, false, l); - } + { $$ = new ExprConcatStrings(CUR_POS, false, new vector({$1, $3})); } | expr_op '-' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.create("__sub")), $1), $3); } | expr_op '*' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.create("__mul")), $1), $3); } | expr_op '/' expr_op { $$ = new ExprApp(CUR_POS, new ExprApp(new ExprVar(data->symbols.create("__div")), $1), $3); } @@ -461,13 +457,13 @@ attrs : attrs attr { $$ = $1; $1->push_back(AttrName(data->symbols.create($2))); } | attrs string_attr { $$ = $1; - ExprString *str = dynamic_cast($2); + ExprString * str = dynamic_cast($2); if (str) { $$->push_back(AttrName(str->s)); delete str; } else - throw ParseError(format("dynamic attributes not allowed in inherit at %1%") - % makeCurPos(@2, data)); + throw ParseError(format("dynamic attributes not allowed in inherit at %1%") + % makeCurPos(@2, data)); } | { $$ = new AttrPath; } ; @@ -476,12 +472,12 @@ attrpath : attrpath '.' attr { $$ = $1; $1->push_back(AttrName(data->symbols.create($3))); } | attrpath '.' string_attr { $$ = $1; - ExprString *str = dynamic_cast($3); + ExprString * str = dynamic_cast($3); if (str) { $$->push_back(AttrName(str->s)); delete str; } else - $$->push_back(AttrName(static_cast($3))); + $$->push_back(AttrName($3)); } | attr { $$ = new vector; $$->push_back(AttrName(data->symbols.create($1))); } | string_attr @@ -491,7 +487,7 @@ attrpath $$->push_back(AttrName(str->s)); delete str; } else - $$->push_back(AttrName(static_cast($1))); + $$->push_back(AttrName($1)); } ; @@ -502,7 +498,7 @@ attr string_attr : '"' string_parts '"' { $$ = $2; } - | DOLLAR_CURLY expr '}' { $$ = new ExprConcatStrings(CUR_POS, true, new vector(1, $2)); } + | DOLLAR_CURLY expr '}' { $$ = $2; } ; expr_list