This adds a mechanism to the compiler to compile an expression without
emitting any code. This allows for detected dead code to still be
compiled to detect errors & warnings inside of it.
Change-Id: Ie78479173570e9c819d8f32ae683ce34234a4c5d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7767
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
This optimiser can rewrite some expressions into more efficient forms,
and warn users about those cases.
As a proof-of-concept, only some simple boolean comparisons are
supported for now.
Change-Id: I7df561118cfbad281fc99523e859bc66e7a1adcb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7766
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
This adds a very minimal amount of additional Rc-increments (~1 per
compilation), but makes it a lot easier to add an AST-optimising
compiler pass without incurring a lot of extra cost.
Change-Id: I57208bdfc8882e3ae21c5850e14aa380d3ccea36
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7765
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
This would make it possible to implement something like a linter based
on the tvix-eval compiler warnings.
Change-Id: I1feb4e7c4a44be7d1204b0a962ab522fd32b93c6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7763
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
There was probably a misunderstanding somewhere about the
with_stack_size being related to how far away it is from the with, but
it is about whether there is a with at all.
This broke a warning (`UselessInherit`), and may actually have let to
more inefficient codegen in some cases.
Change-Id: I08338ea59ae39dad01ca8a4e09d934a936cdea2f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7762
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
... without them, using the new Builtins API is basically impossible
for library consumers.
Change-Id: Ice0557a2e55e12d812f51bf5a99e6b8c91ad1b91
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7755
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Code probably rarely relies on these, but it's not hard to support them.
Change-Id: I8499fec34efaf031f9c013bbd370a13db929a2a3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7772
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Autosubmit: sterni <sternenseemann@systemli.org>
This will eventually force us to have a base builtins set in common with
C++ Nix, i.e. all 2.3 builtins except the controversial
builtins.valueSize.
Change-Id: I2c767f07d6a14711911658e87da9f18ede57a143
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7747
Autosubmit: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Implements externally tagged enum deserialisation. Other serialisation
methods are handled by serde internally using the existing methods.
See the tests for examples.
Change-Id: Ic4a9da3b5a32ddbb5918b1512e70c3ac5ce64f04
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7721
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
With this is_valid_nix_identifier should line up with the upstream lexer
definition:
ID [a-zA-Z\_][a-zA-Z0-9\_\'\-]*
While we're working on this, add a simple test checking the various
formatting rules. Interestingly, it would not be suitable as an identity
test, since you have to write
{ "assert" = null; }
in order to avoid an evaluation error, but C++ Nix is happy to print
this as
{ assert = null; }
– maybe should be considered to be a bug.
Change-Id: I0a4e1ccb5033a80f3767fb8d1c4bba08d303c5d8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7744
Autosubmit: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
Previously the construction of globals (a compiler-only concept) and
builtins (a (now) user-facing API) was intermingled between multiple
different modules, and kind of difficult to understand.
The complexity of this had grown in large part due to the
implementation of `builtins.import`, which required the notorious
"knot-tying" trick using Rc::new_cyclic (see cl/7097) for constructing
the set of globals.
As part of the new `Evaluation` API users should have the ability to
bring their own builtins, and control explicitly whether or not impure
builtins are available (regardless of whether they're compiled in or
not).
To streamline the construction and allow the new API features to work,
this commit restructures things by making these changes:
1. The `tvix_eval::builtins` module is now only responsible for
exporting sets of builtins. It no longer has any knowledge of
whether or not certain sets (e.g. only pure, or pure+impure) are
enabled, and it has no control over which builtins are globally
available (this is now handled in the compiler).
2. The compiler module is now responsible for both constructing the
final attribute set of builtins from the set of builtins supplied
by a user, as well as for populating its globals (that is
identifiers which are available at the top-level scope).
3. The `Evaluation` API now carries a `builtins` field which is
populated with the pure builtins by default, and can be extended by
users.
4. The `import` feature has been moved into the compiler, as a
special case. In general, builtins no longer have the ability to
reference the "fix point" of the globals set.
This should not change any functionality, and in fact preserves minor
differences between Tvix/Nix that we already had (such as
`builtins.builtins` not existing).
Change-Id: Icdf5dd50eb81eb9260d89269d6e08b1e67811a2c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7738
Reviewed-by: sterni <sternenseemann@systemli.org>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
This makes it easier to interface this error with other crates.
Change-Id: I4947ea6097608f8c0427fb94a819ef748d94ea4b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7711
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
The `im::OrdMap` is already small and cheap to copy while sharing
memory, so this is not required anymore.
Only the `KV` variant may have slightly larger content, but in
practice this doesn't seem to make a difference when comparing the two
variants and this one is less complicated.
Change-Id: I64a563b209a2444125653777551373cb2989ca7d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7677
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This uses the `im::OrdMap` for `NixAttrs` to enable sharing of memory
between different iterations of a map.
This slightly speeds up eval, but not significantly. Future work might
include benchmarking whether using a `HashMap` and only ordering in
cases where order is actually required would help.
This switches to a fork of `im` that fixes some bugs with its OrdMap
implementation.
Change-Id: I2f6a5ff471b6d508c1e8a98b13f889f49c0d9537
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7676
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
The conversion from im::Vector -> Vec is cheaper for NixList
construction (of course), so where possible we should make use of
that.
This updates most builtins dealing with lists to use Vector directly,
and marks the function constructing NixList from Vec as deprecated so
that we get appropriate warnings in places where it's still in use.
These places are currently inside of JSON serialisation logic which is
in flux right now, so lets leave them as-is until it's stabilised.
Change-Id: I037f12a2800f2576db4d9526bd935efd079163f0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7671
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This is a persistent, structurally sharing data structure which is
more efficient in some of our use-cases. I have verified the
efficiency improvement using `hyperfine` repeatedly over expressions
on nixpkgs.
Lists are not the most performance-critical structure in Nix (that
would be attribute sets), but we can already see a small (~5-10%)
improvement.
Note that there are a handful of cases where we still go via `Vec`
that need to be fixed, most notable for `builtins.sort` which can not
currently be implemented directly using `im::Vector` because of a
restrictive type bound.
Change-Id: I237cc50cbd7629a046e5a5e4601fbb40355e551d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7670
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
It's been a while since the last time, so quite a lot of stuff has
accumulated here.
Change-Id: I0762827c197b30a917ff470fd8ae8f220f6ba247
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7597
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Introduces continuation-passing-based trampolining of thunk forcing to
avoid recursing when forcing deeply nested expressions.
This is required for evaluating large expressions.
This change was extracted out of cl/7362.
Co-authored-by: Vincent Ambo <tazjin@tvl.su>
Co-authored-by: Griffin Smith <grfn@gws.fyi>
Change-Id: Ifc1747e712663684b2fff53095de62b8459a47f3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7551
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
... if they are known. We currently do not propagate names correctly
for curried functions.
Change-Id: I19d57fb30a5c0000ccdf690b91076f6b2191de23
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7596
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This value creates a human-readable explanation of a value. This can
be used to implement documentation related functionality.
For some values, the amount of information displayed can be expanded
quite a bit.
Change-Id: Ie8c400feae909e7680af163596f99060262e4241
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7592
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This type allows for temporarily compatibility with the C++ Nix store,
specifically (for now) it gives us the store directory used by Nix and
imports files the same way.
Change-Id: I4767794ef2863eba49661315c63c4e17de946d60
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7587
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Having a multi-line docstring yields multiple doc-attributes in order,
however we were previously discarding all but the first one.
This reduces them into a single string instead, which can then be
displayed as multi-line documentation.
Change-Id: I1f237956cdea2e4c746d3f13744e0373c1c645a6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7594
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
This "ties the knot" of importing files into a store when referring
to them through path literals, e.g. inside of strings.
I'm not yet sure if this interface is sufficient for
builtins.path (which we haven't implemented at all yet), but it's
enough to wire up eval & store initially.
In the default implementations nothing interesting happens in this
function at all.
Change-Id: Ie01ff4161617d1e743a68dbd1a5e54c1b40c0990
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7582
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Returns the store directory through EvalIO::store_dir.
Note that this is _optional_ in Tvix, as an evaluation can occur in a
context where there simply is no store directory. In those contexts,
`builtins.storeDir` returns `null` in Tvix.
This would only happen in contexts like Tvixbolt (or completely
unrelated use-cases) in practice.
Co-Authored-By: Vincent Ambo <tazjin@tvl.su>
Change-Id: I5a752c7e89b2f75bd7efb082dbfa5b25e3b1ff3b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7452
Autosubmit: Adam Joseph <adam@westernsemico.com>
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This shouldn't be available if we've built a "pure" crate.
Change-Id: I7c85827ee212890252ff7e0b6242e2c52618cba5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7572
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
With this change, the behaviour of reading a string from a file path
is controlled by the provided `EvalIO` structure.
This is a huge step towards abstracting away I/O behaviour correctly.
Change-Id: Ifde8e46cd863b16e0301dca45a434ad27560399f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7567
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This lets users set the `io_handle` field on an `Evaluation`, which is
then propagated to the VM.
Change-Id: I616d7140724fb2b4db47c2ebf95451d5303a487a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7566
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This trait is going to be used to abstract filesystem interactions in
Tvix.
For now, it only contains a `read_to_string` method that closely
mirrors `std::fs::read_to_string`.
As a first step, to see how this works in practice, we will thread
through only this function to the various relevant parts.
Two implementations are provided in tvix-eval itself: A dummy
implementation (which just returns ErrorKind::NotImplemented for all
operations), and a std implementation which delegates to `std`
functions.
Change-Id: Ied3e3bf4bd0e874dd84e166190e3873a0f923ddb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7565
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This type carries the information required for calculating a
span (i.e. the chunk and offset), instead of the span itself. The span
is then only calculated in cases where it is required (when throwing
errors).
This reduces the eval time for
`builtins.length (builtins.attrNames (import <nixpkgs> {}))` by *one
third*!
The data structure in chunks that carries span information reduces
in-memory size by trading off the speed of retrieving span
information. This is because the span information is only actually
required when throwing errors (or emitting warnings).
However, somewhere along the way we grew a dependency on carrying span
information in thunks (for correctly reporting error chains). Hitting
the code paths for span retrieval was expensive, and carrying the
spans in a different way would still be less cache-efficient. This
change is the best tradeoff I could come up with.
Refs: b/229.
Change-Id: I27d4c4b5c5f9be90ac47f2db61941e123a78a77b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7558
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Having thunks which, when forced, execute native Rust code rather
than interpreted opcodes lets us avoid having to bundle
`src/libexpr/primops/derivation.nix` like cppnix does by implementing
it in Rust instead.
Change-Id: If91d77a6736234321eee87ba4b4777eed5a3fe1c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7450
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Instead of finding locals by doing 2x O(n) walks over the compiler's
locals list, use a secondary name-based index for resolving locals by
name.
Previously, almost 60% (!!) of eval time on some expressions over
nixpkgs was spent in `Local::has_name`. This function doesn't even
exist anymore now, and eval speed about doubles as a result.
Note that this doesn't exactly make the locals code easier to read,
but I'm also not sure what we can simplify in there in general.
This fixes b/227.
Change-Id: I29ce5eb9452b02d3b358c673e1f5cf8082e2fef9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7560
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
With this change, it should be possible to have both existing
use-cases (CLI & Tvixbolt) use the same API.
Change-Id: I2195264f08cc892177b559a28660dc5f98e48e41
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7545
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This is required for passing through NIX_PATH from the CLI.
Change-Id: If129df79ef9c3ffab31408adb85679909276c4f0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7544
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
This should make no difference in Nix builds, but allows running tests
locally again with `cargo test` for //tvix/eval.
Change-Id: I97d61840143d5c14db61d5862781bf635f9a28e7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7590
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
In //tvix/eval:
* criterion bumped to 4.0, which at least depends on clap 3.x instead
of 2.x, which is less incompatible
In //tvix/cli:
* no changes required
In //tvix/nix_cli:
* some minor changes for compatibility with clap 4.0, no functionality
changes
Change-Id: If793f64b59fcaa2402d3d483ddbab4092f32df03
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7588
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
The tvix-eval project is independent from any *uses* of the evaluator,
such as the tvix-repl.
This functionality has been split out into a separate "tvix-cli"
crate. Note that this doesn't have to mean that this CLI crate is the
"final" CLI crate for tvix, the point of this is not "getting the CLI
structure right" but rather "getting the evaluator structure right".
This reshuffling is part of restructuring the way that functionality
like store communication is injected into language evaluation.
Note that at this commit the new CLI crate is not at feature-parity.
Change-Id: Id0af03dc8e07ef09a9f882a89612ad555eca8f93
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7541
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This removes internal uses of the previous crate::eval module, which
is being removed.
Change-Id: I5fb3c53460a9c5381853d0258f9ed074ab23c630
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7543
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
A step towards something more like how I imagine the future public API
for tvix-eval. Please note that this is definitely not the final
version yet, but it's better than the previous API that either exposed
a side-effecting blackbox, or a very low-level "interface".
The basic idea is that an evaluation of some Nix code is requested by
a caller with various parameters, but not all callers are interested
in all of these parameters.
There are also some bits of information that are returned from an
evaluation that are not necessarily relevant to all callers.
To support this somewhat ergonomically, the API is built around an
`Evaluation` struct that is configured by the caller with the various
parameters and then "executed".
Change-Id: I71826f3897126898adc2873d31c44d3eaf5c2be0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7542
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Introduces granular dependency builds using crate2nix, bootstrapped
off the generated configuration from the newly introduced
workspace (see cl/7533).
This commit checks in the generated Cargo.nix file which can be
regenerated with a parameterless invocation of `crate2nix generate` in
`//tvix`. I tried generating this in IFD, but it turned out to be
harder than what seemed worthwhile for now.
In this setup, the various build targets for Rust projects end up
being attributes of the imported `Cargo.nix` file at the `tvix.crates`
attribute. These still lack configuration, however, which has been
fixed in the various `default.nix` files of individual projects.
Note that we (temporarily) lose the ability to build tvix-eval's
benchmarks in CI. I haven't figured out what magic incantation summons
them from the void again ...
The `eval-okay-readDir` tests from both test suites have been disabled
because they fail for unknown reasons when run in this new derivation.
Somebody will have to debug it!
Change-Id: I2014614ccb9c8951aedbd71df7966ca191a13695
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7538
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI