about summary refs log tree commit diff
path: root/tvix/eval/src/value/function.rs (follow)
AgeCommit message (Collapse)AuthorFilesLines
2022-12-21 r/5453 feat(tvix/eval): remove `derive(Copy)` from UpvaluesAdam Joseph1-4/+18
Change-Id: I0fa069fbeff6718a765ece948c2c1bce285496f7 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7449 Reviewed-by: grfn <grfn@gws.fyi> Tested-by: BuildkiteCI
2022-12-21 r/5452 feat(tvix/eval): wrap Closure in Rc<> to match cppnix semanticsAdam Joseph1-15/+1
Change-Id: I595087eff943d38a9fc78a83d37e207bb2ab79bc Reviewed-on: https://cl.tvl.fyi/c/depot/+/7443 Reviewed-by: grfn <grfn@gws.fyi> Tested-by: BuildkiteCI
2022-11-26 r/5325 feat(tvix/eval): add Closure::ptr_eq()Adam Joseph1-0/+6
See cl/7368 Change-Id: I97630994c3d65f4d16414a0da236ce000a5b6d33 Signed-off-by: Adam Joseph <adam@westernsemico.com> Reviewed-on: https://cl.tvl.fyi/c/depot/+/7374 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-11-26 r/5324 feat(tvix/eval): wrap Closure::upvalues in RcAdam Joseph1-3/+6
See cl/7372; Nix equality semantics require the ability to track pointer equality of upvalue-sets. Signed-off-by: Adam Joseph <adam@westernsemico.com> Change-Id: I82ba517499cf370189a80355e4e46a5caaab7153 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7373 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-11-05 r/5250 refactor(tvix/eval): rename Opcode::DataLocalIdx to DataStackIdxAdam Joseph1-1/+1
It is very confusing that this opcode is called DataLocalIdx, but it carries a StackIdx rather than a LocalIdx. It seems like this really ought to be called DataStackIdx, but maybe I've misunderstood; if so please explain it to me. Change-Id: I91f6ffa759412beef0b91d3c19ec0d873fe51b99 Signed-off-by: Adam Joseph <adam@westernsemico.com> Reviewed-on: https://cl.tvl.fyi/c/depot/+/7088 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-11-04 r/5236 fix(tvix/eval): remove impl PartialEq for ValueAdam Joseph1-2/+2
It isn't possible to implement PartialEq properly for Value, because any sensible implementation needs to force() thunks, which cannot be done without a `&mut VM`. The existing derive(PartialEq) has false negatives, which caused the bug which cl/7142 fixed. Fortunately that bug was easy to find, but a silent false negative deep within the bowels of nixpkgs could be a real nightmare to hunt down. Let's just remove the PartialEq impl for Value, and the other derive(PartialEq)'s that depend on it. Signed-off-by: Adam Joseph <adam@westernsemico.com> Change-Id: Iacd3726fefc7fc1edadcd7e9b586e04cf8466775 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7144 Reviewed-by: kanepyork <rikingcoding@gmail.com> Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-10-23 r/5186 feat(tvix/eval): initial attempt at setting lambda namesVincent Ambo1-9/+7
When compiling a lambda, take the name of the outer slot (if available) and store it as the name on the lambda. These names are then shown in the observer, and nowhere else (so far). It is of course common for these things to thread through many different context levels (e.g. `f = a: b: c: ...`), in this setup only the outermost closure or thunk gains the name, but it's better than nothing. Change-Id: I681ba74e624f2b9e7a147144a27acf364fe6ccc7 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7065 Reviewed-by: grfn <grfn@gws.fyi> Autosubmit: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-10-19 r/5159 feat(tvix/eval): deduplicate overlap between Closure and ThunkAdam Joseph1-36/+23
This commit deduplicates the Thunk-like functionality from Closure and unifies it with Thunk. Specifically, we now have one and only one way of breaking reference cycles in the Value-graph: Thunk. No other variant contains a RefCell. This should make it easier to reason about the behavior of the VM. InnerClosure and UpvaluesCarrier are no longer necessary. This refactoring allowed an improvement in code generation: `Rc<RefCell<>>`s are now created only for closures which do not have self-references or deferred upvalues, instead of for all closures. OpClosure has been split into two separate opcodes: - OpClosure creates non-recursive closures with no deferred upvalues. The VM will not create an `Rc<RefCell<>>` when executing this instruction. - OpThunkClosure is used for closures with self-references or deferred upvalues. The VM will create a Thunk when executing this opcode, but the Thunk will start out already in the `ThunkRepr::Evaluated` state, rather than in the `ThunkRepr::Suspeneded` state. To avoid confusion, OpThunk has been renamed OpThunkSuspended. Thanks to @sterni for suggesting that all this could be done without adding an additional variant to ThunkRepr. This does however mean that there will be mutating accesses to `ThunkRepr::Evaluated`, which was not previously the case. The field `is_finalised:bool` has been added to `Closure` to ensure that these mutating accesses are performed only on finalised Closures. Both the check and the field are present only if `#[cfg(debug_assertions)]`. Change-Id: I04131501029772f30e28da8281d864427685097f Signed-off-by: Adam Joseph <adam@westernsemico.com> Reviewed-on: https://cl.tvl.fyi/c/depot/+/7019 Tested-by: BuildkiteCI Reviewed-by: tazjin <tazjin@tvl.su>
2022-10-17 r/5154 feat(tvix/eval): Validate closed formalsGriffin Smith1-0/+20
Validate "closed formals" (formal parameters without an ellipsis) via a new ValidateClosedFormals op, which checks the arguments (in an attr set at the top of the stack) against the formal parameters on the Lambda in the current frame, and returns a new UnexpectedArgument error (including the span of the formals themselves!!) if any arguments aren't allowed Change-Id: Idcc47a59167a83be1832a6229f137d84e426c56c Reviewed-on: https://cl.tvl.fyi/c/depot/+/7002 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-10-17 r/5153 feat(tvix/eval): Record formals on lambdaGriffin Smith1-2/+14
In preparation for both implementing the `functionArgs` builtin and adding support for validating closed formals, record information about the formal arguments to a function *on the Lambda itself*. This may seem a little odd for the purposes of just closed formal checking, but is something we have to have anyway for builtins.functionArgs so I figured I'd do it this way to kill both birds with one stone. Change-Id: Ie3770a607bf352a1eb395c79ca29bb25d5978cd8 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7001 Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-10-17 r/5151 docs(tvix/eval) comments for various fieldsAdam Joseph1-0/+10
Change-Id: I8dcddf2b419761e475e71215c199eef2f7dc61dc Reviewed-on: https://cl.tvl.fyi/c/depot/+/7028 Autosubmit: Adam Joseph <adam@westernsemico.com> Tested-by: BuildkiteCI Reviewed-by: tazjin <tazjin@tvl.su>
2022-10-16 r/5142 feat(tvix/eval): remove Clone instance from Chunk and LambdaAdam Joseph1-1/+1
Lambda has a quite large and variable-sized runtime representation, unlike Rc<Lambda>. It would be easy to accidentally call clone() on this and create input-dependent performance regressions. Nothing in the codebase is currently using Lambda.clone(). Let's remove the derived instance. If it's really needed it is very easy to add it back in, but whoever does that will have to look at the struct they're adding Clone to, which will hopefully prompt them to think about whether or not that's really what they want to do. Change-Id: I7806a741862ab4402229839ce3f4ea75aafd6d12 Reviewed-on: https://cl.tvl.fyi/c/depot/+/7029 Autosubmit: Adam Joseph <adam@westernsemico.com> Reviewed-by: tazjin <tazjin@tvl.su> Tested-by: BuildkiteCI
2022-09-18 r/4908 refactor(tvix/eval): Don't (ab)use PartialEq for Nix equalityGriffin Smith1-3/+3
Using rust's PartialEq trait to implement Nix equality semantics is reasonably fraught with peril, both because the actual laws are different than what nix expects, and (more importantly) because certain things actually require extra context to compare for equality (for example, thunks need to be forced). This converts the manual PartialEq impl for Value (and all its descendants) to a *derived* PartialEq impl (which requires a lot of extra PartialEq derives on miscellanious other types within the codebase), and converts the previous nix-semantics equality comparison into a new `nix_eq` method. This returns an EvalResult, even though it can't currently return an error, to allow it to fail when eg forcing thunks (which it will do soon). Since the PartialEq impls for Value and NixAttrs are now quite boring, this converts the generated proptests for those into handwritten ones that cover `nix_eq` instead Change-Id: If3da7171f88c22eda5b7a60030d8b00c3b76f672 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6650 Autosubmit: grfn <grfn@gws.fyi> Tested-by: BuildkiteCI Reviewed-by: tazjin <tazjin@tvl.su>
2022-09-11 r/4800 refactor(tvix/eval): introduce Upvalues struct in closures & thunksVincent Ambo1-6/+9
This struct will be responsible for tracking upvalues (and is a convenient place to introduce optimisations for reducing value clones) instead of a plain value vector. The main motivation for this is that the upvalues will have to capture the `with`-stack fully and I want to avoid duplicating the logic for this between the two capturing types. Change-Id: I6654f8739fc2e04ca046e6667d4a015f51724e99 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6485 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
2022-09-06 r/4677 refactor(tvix/eval): introduce UpvalueCarrier traitVincent Ambo1-16/+11
This trait abstracts over the commonalities of upvalue handling between closures and thunks. It allows the VM to simplify the code used for setting up upvalues, without duplicating between the two different types. Note that this does not yet refactor the VM code to optimally make use of this. Change-Id: If8de5181f26ae1fa00d554f1ae6ea473ee4b6070 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6347 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
2022-09-06 r/4667 feat(tvix/eval): implement OpFinalise instructionVincent Ambo1-0/+11
This instruction finalises the initialisation of deferred upvalues in closures (and soon, thunks). The compiler does not yet emit this instruction, some more accounting is needed for that. Change-Id: Ic4181b26e19779e206f51e17388559400da5f93a Reviewed-on: https://cl.tvl.fyi/c/depot/+/6337 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
2022-09-06 r/4659 fix(tvix/eval): instantiate *new* closures from blueprints each timeVincent Ambo1-2/+2
The previous closure refactoring introduced a bug in which the same closure object would get mutated constantly for each instance of a closure, which is incorrect behaviour. This commit instead introduces an explicit new Value variant for the internal "blueprint" that the compiler generates (essentially just the lambda) and uses this variant to construct the closure at runtime. If the blueprint ever leaks out to a user somehow that is a critical bug and tvix-eval will panic. As a ~treat~ test for this, the fibonacci function is being used as it is a self-recursive closure (i.e. different instantiations of the same "blueprint") getting called with different values and it's good to have it around. Change-Id: I485de675e9bb0c599ed7d5dc0f001eb34ab4c15f Reviewed-on: https://cl.tvl.fyi/c/depot/+/6323 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
2022-09-06 r/4651 refactor(tvix/eval): encapsulate internal mutability within ClosureVincent Ambo1-7/+30
This is required to efficiently construct the upvalue array at runtime, as there are situations where during Closure construction multiple things already have a reference to the closure (e.g. a self-reference). Change-Id: I35263b845fdc695dc873de489f5168d39b370f6a Reviewed-on: https://cl.tvl.fyi/c/depot/+/6312 Tested-by: BuildkiteCI Reviewed-by: sterni <sternenseemann@systemli.org>
2022-09-03 r/4625 feat(tvix/eval): compile creation of closure objectsVincent Ambo1-1/+11
Fully implements the instructions for compiling closure objects (without runtime handling yet). Closure (and thunk) objects are created at runtime by capturing all known upvalues. To represent this, the instructions for creating them need to have a variable number of arguments. Due to that, this commit introduces new variants in OpCode that are not actually operations, but data. If the VM is implemented correctly, the instruction pointer should never point at these. Due to this, the VM will panic if it sees a data operand during an execution run. Change-Id: Ic56b49b3a42736dc437751e76df0e89c8d0619c6 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6291 Tested-by: BuildkiteCI Reviewed-by: grfn <grfn@gws.fyi>
2022-09-03 r/4623 feat(tvix/eval): implement compilation of upvalue accessVincent Ambo1-0/+2
This adds a new upvalue tracking structure in the compiler to resolve upvalues and track their positions within a function when compiling a closure. The compiler will emit runtime upvalue access instructions after this commit, but the creation of the runtime closure object etc. is not yet wired up. Change-Id: Ib0c2c25f686bfd45f797c528753068858e3a770d Reviewed-on: https://cl.tvl.fyi/c/depot/+/6289 Tested-by: BuildkiteCI Reviewed-by: grfn <grfn@gws.fyi>
2022-09-03 r/4605 refactor(tvix/eval): introduce Closure struct in Value typeVincent Ambo1-0/+28
This struct will carry the upvalue machinery in addition to the lambda itself. For now, all lambdas are wrapped in closures (though technically analysis of the environment can later remove innermost Closure wrapper, but this optimisation may not be worth it). Change-Id: If2b68549ec1ea4ab838fdc47a2181c694ac937f2 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6269 Reviewed-by: grfn <grfn@gws.fyi> Tested-by: BuildkiteCI