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Optimize small lists

The value pointers of lists with 1 or 2 elements are now stored in the
list value itself. In particular, this makes the "concatMap (x: if
cond then [(f x)] else [])" idiom cheaper.
This commit is contained in:
Eelco Dolstra 2015-07-23 22:05:09 +02:00
parent 14be783676
commit b83801f8b3
11 changed files with 157 additions and 121 deletions

View file

@ -1127,13 +1127,13 @@ static void opQuery(Globals & globals, Strings opFlags, Strings opArgs)
attrs2["type"] = "bool";
attrs2["value"] = v->boolean ? "true" : "false";
xml.writeEmptyElement("meta", attrs2);
} else if (v->type == tList) {
} else if (v->isList()) {
attrs2["type"] = "strings";
XMLOpenElement m(xml, "meta", attrs2);
for (unsigned int j = 0; j < v->list.length; ++j) {
if (v->list.elems[j]->type != tString) continue;
for (unsigned int j = 0; j < v->listSize(); ++j) {
if (v->listElems()[j]->type != tString) continue;
XMLAttrs attrs3;
attrs3["value"] = v->list.elems[j]->string.s;
attrs3["value"] = v->listElems()[j]->string.s;
xml.writeEmptyElement("string", attrs3);
}
}

View file

@ -52,7 +52,7 @@ bool createUserEnv(EvalState & state, DrvInfos & elems,
Path drvPath = keepDerivations ? i.queryDrvPath() : "";
Value & v(*state.allocValue());
manifest.list.elems[n++] = &v;
manifest.listElems()[n++] = &v;
state.mkAttrs(v, 16);
mkString(*state.allocAttr(v, state.sType), "derivation");
@ -69,7 +69,7 @@ bool createUserEnv(EvalState & state, DrvInfos & elems,
state.mkList(vOutputs, outputs.size());
unsigned int m = 0;
for (auto & j : outputs) {
mkString(*(vOutputs.list.elems[m++] = state.allocValue()), j.first);
mkString(*(vOutputs.listElems()[m++] = state.allocValue()), j.first);
Value & vOutputs = *state.allocAttr(v, state.symbols.create(j.first));
state.mkAttrs(vOutputs, 2);
mkString(*state.allocAttr(vOutputs, state.sOutPath), j.second);