lix/src/libexpr
pennae 9ac836d1d6 don't use Symbols for strings
string expressions by and large do not need the benefits a Symbol gives us,
instead they pollute the symbol table and cause unnecessary overhead for almost
all strings. the one place we can think of that benefits from them (attrpaths
with expressions) extracts the benefit in the parser, which we'll have to touch
anyway when changing ExprString to hold strings.

this gives a sizeable improvement on of 3-5% on all benchmarks we've run.

 before

  nix search --no-eval-cache --offline ../nixpkgs hello
    Time (mean ± σ):      8.844 s ±  0.045 s    [User: 6.750 s, System: 1.663 s]
    Range (min … max):    8.758 s …  8.922 s    20 runs

  nix eval -f ../nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
    Time (mean ± σ):     367.4 ms ±   3.3 ms    [User: 332.3 ms, System: 35.2 ms]
    Range (min … max):   364.0 ms … 375.2 ms    20 runs

  nix eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
    Time (mean ± σ):      2.810 s ±  0.030 s    [User: 2.517 s, System: 0.225 s]
    Range (min … max):    2.742 s …  2.854 s    20 runs

 after

  nix search --no-eval-cache --offline ../nixpkgs hello
    Time (mean ± σ):      8.533 s ±  0.068 s    [User: 6.485 s, System: 1.642 s]
    Range (min … max):    8.404 s …  8.657 s    20 runs

  nix eval -f ../nixpkgs/pkgs/development/haskell-modules/hackage-packages.nix
    Time (mean ± σ):     347.6 ms ±   3.1 ms    [User: 313.1 ms, System: 34.5 ms]
    Range (min … max):   343.3 ms … 354.6 ms    20 runs

  nix eval --raw --impure --expr 'with import <nixpkgs/nixos> {}; system'
    Time (mean ± σ):      2.709 s ±  0.032 s    [User: 2.414 s, System: 0.232 s]
    Range (min … max):    2.655 s …  2.788 s    20 runs
2022-01-19 14:48:00 +01:00
..
flake allow modifying lockfile commit msg with nix config option 2022-01-18 16:10:27 -07:00
primops Remove non-method mk<X> functions 2022-01-04 18:40:39 +01:00
attr-path.cc Rename findDerivationFilename -> findPackageFilename 2021-07-19 18:10:10 +02:00
attr-path.hh Rename findDerivationFilename -> findPackageFilename 2021-07-19 18:10:10 +02:00
attr-set.cc Remove EvalState::mkAttrs() 2022-01-04 20:29:17 +01:00
attr-set.hh optimize removeAttrs builtin 2022-01-14 14:01:52 +01:00
common-eval-args.cc Remove non-method mkString() 2022-01-04 18:24:42 +01:00
common-eval-args.hh Support --eval-store in nix-instantiate and nix-build 2021-07-22 09:59:51 +02:00
eval-cache.cc libcmd/installables: force re-evaluation of cached failures 2021-04-19 19:51:04 +02:00
eval-cache.hh libcmd/installables: force re-evaluation of cached failures 2021-04-19 19:51:04 +02:00
eval-inline.hh Improve error formatting 2021-01-21 11:02:09 +01:00
eval.cc cache more often-used symbols for primops 2022-01-13 13:58:33 +01:00
eval.hh Merge pull request #5906 from pennae/primops-optimization 2022-01-18 19:43:28 +01:00
fetchurl.nix Move <nix/fetchurl.nix> into the nix binary 2020-12-22 14:43:20 +01:00
function-trace.cc Revert the enum struct change 2020-06-18 22:11:26 +00:00
function-trace.hh Hide FunctionCallTrace constructor/destructor 2020-01-05 16:21:34 +01:00
get-drvs.cc Ensure that attrsets are sorted 2022-01-04 18:00:33 +01:00
get-drvs.hh Squashed get CA derivations building 2020-08-07 19:51:55 +00:00
imported-drv-to-derivation.nix Move some corepkgs into the nix binary 2020-03-11 16:57:48 +01:00
json-to-value.cc Remove EvalState::mkAttrs() 2022-01-04 20:29:17 +01:00
json-to-value.hh Fix extra ; warnings involving MakeError 2019-11-10 11:24:47 -05:00
lexer.l remove ExprIndStr 2022-01-19 13:39:42 +01:00
local.mk Merge pull request #5175 from Pamplemousse/make 2021-08-30 12:44:29 +02:00
nix-expr.pc.in pkg-config files: Use c++17 2019-03-14 14:11:12 +01:00
nixexpr.cc avoid allocations in SymbolTable::create 2022-01-13 18:06:15 +01:00
nixexpr.hh don't use Symbols for strings 2022-01-19 14:48:00 +01:00
parser.y don't use Symbols for strings 2022-01-19 14:48:00 +01:00
primops.cc Merge pull request #5906 from pennae/primops-optimization 2022-01-18 19:43:28 +01:00
primops.hh libexpr: throw a more helpful eval-error if a builtin is not available due to a missing feature-flag 2021-09-29 11:57:15 +02:00
symbol-table.hh avoid allocations in SymbolTable::create 2022-01-13 18:06:15 +01:00
value-to-json.cc Support range-based for loop over list values 2021-11-25 16:31:39 +01:00
value-to-json.hh toJSON: report error position for fancier output 2021-10-25 21:17:52 +00:00
value-to-xml.cc Support range-based for loop over list values 2021-11-25 16:31:39 +01:00
value-to-xml.hh toXML: display errors position 2021-11-13 20:33:34 -05:00
value.hh optimize ExprConcatStrings::eval 2022-01-12 10:07:21 +01:00