Note that native code gen is currently exempt from any security guarantees as it's a pre-production R&D component right now. This will change in the future as we deploy it to production.
It looks like all three functions actually have been deprecated in Lua
5.1, and removed in Lua 5.2.
We do not plan to remove them to retain backwards compatibility, but the
RFC should be more precise.
We've made a few small changes to reduce the amount of stack we use when
typechecking nested method calls (eg `foo:bar():baz():quux()`).
We've also fixed a small bytecode compiler issue that caused us to emit
redundant jump instructions in code that conditionally uses `break` or
`continue`.
On the new solver, we've switched to a new, better way to handle
augmentations to unsealed tables. We've also made some substantial
improvements to type inference and error reporting on function calls.
These things should both be on par with the old solver now.
The main improvements to the native code generator have been elimination
of some redundant type tag checks. Also, we are starting to inline
particular fastcalls directly to IR.
---------
Co-authored-by: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
1. Added information about Homebrew installation (based off this
information [here](https://formulae.brew.sh/formula/luau#default))
2. Added details related to installing binary files that are downloaded
3. Rearranged and added titles for easier reading
Fixes#791.
Co-authored-by: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
This week we only have updates to new type solver and JIT. Both projects
are still in the process of being built out. Neither are ready for
general use yet.
In the new solver, we fixed issues with recursive type aliases.
Duplicated type parameters are once again reported, exported types are
being recorder and function argument names are placed inside function
types.
We also made improvements to restore parts of bidirectional type
tracking.
On native code generation side, namecall instruction lowering was fixed,
we fixed inconsistencies in IR command definitions and added utility
function to help with constant folding.
* Fix a bug where reading a property from an unsealed table caused
inference to improperly infer the existence of that property.
* Fix#827
We have also made a lot of progress on the new solver and the JIT. Both
projects are still in the process of being built out. Neither are ready
for general use yet.
We are mostly working to tighten up how the new solver handles
refinements and updates to unsealed tables to bring it up to the same
level as the old solver.
---------
Co-authored-by: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
* Fixed rare use-after-free in analysis during table unification
A lot of work these past months went into two new Luau components:
* A near full rewrite of the typechecker using a new deferred constraint
resolution system
* Native code generation for AoT/JiT compilation of VM bytecode into x64
(avx)/arm64 instructions
Both of these components are far from finished and we don't provide
documentation on building and using them at this point.
However, curious community members expressed interest in learning about
changes that go into these components each week, so we are now listing
them here in the 'sync' pull request descriptions.
---
New typechecker can be enabled by setting
DebugLuauDeferredConstraintResolution flag to 'true'.
It is considered unstable right now, so try it at your own risk.
Even though it already provides better type inference than the current
one in some cases, our main goal right now is to reach feature parity
with current typechecker.
Features which improve over the capabilities of the current typechecker
are marked as '(NEW)'.
Changes to new typechecker:
* Regular for loop index and parameters are now typechecked
* Invalid type annotations on local variables are ignored to improve
autocomplete
* Fixed missing autocomplete type suggestions for function arguments
* Type reduction is now performed to produce simpler types to be
presented to the user (error messages, custom LSPs)
* Internally, complex types like '((number | string) & ~(false?)) |
string' can be produced, which is just 'string | number' when simplified
* Fixed spots where support for unknown and never types was missing
* (NEW) Length operator '#' is now valid to use on top table type, this
type comes up when doing typeof(x) == "table" guards and isn't available
in current typechecker
---
Changes to native code generation:
* Additional math library fast calls are now lowered to x64: math.ldexp,
math.round, math.frexp, math.modf, math.sign and math.clamp
* For autocomplete, additional information is included in Scope for type
alias name locations and names of imported modules
* Improved autocomplete suggestions in 'for' and 'while' loop headers
* String match functions return types are now optional strings and
numbers because match is not guaranteed at runtime
* Fixed build issue on gcc 11 and up (Fixes
https://github.com/Roblox/luau/issues/806)
`lua_getupvalue()` and `lua_setupvalue()` don't behave as expected when
working with Lua closure whose `Proto` has no debug info. The code
currently uses `sizeupvalues` to do bounds checking of upvalue indices,
but that's the size of the upvalue _names_ array. It will always be `0`
if the `Proto` doesn't have debug info.
This uses `nups` instead, and just returns `""` as the upvalue name if
we don't have one, same as for C closures.
Co-authored-by: Harold Cindy <HaroldCindy@users.noreply.github.com>
* Fix autocompletion of if-then-else expressions
* Fix a potential crash surrounding improper use of `%*` in a string
format specifier
* All Python scripts now invoke Python via `python3` rather than
`python`.
* Improved error handling for string interpolation with too many
arguments.
Co-authored-by: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Co-authored-by: Vyacheslav Egorov <vegorov@roblox.com>
Having the location where the table type is defined is useful for
tracking other info such as documentation comments, or pointing back
through "Go To Definition" functionality etc.
This adds in the required info
Closes#718
We pass an extra `contents` parameter to the string callback function to
provide contextual information for autocomplete.
Because we support both string literals and simple interpolated strings,
we pass it through as a `std::string` value.
This is a breaking change
* Fixed garbage data in module scopes when type graph is not retained
* LOP_MOVE with the same source and target registers is no longer
generated (Fixes https://github.com/Roblox/luau/issues/793)
### Problem
ubuntu-latest was updated to 22.04 which removes clang++-10 we used for
coverage stats and creates a pre-compiled binary that requires a glibc
upgrade https://github.com/Roblox/luau/issues/773
### Solution
Pin to ubuntu-20.04 using multi-value matrix configurations.
In coverage configuration, we use clang++-10 once again.
* Fixed unions of `nil` types displaying as `?`
* Internal normalization now handles class types which can make
previously failing (incorrectly) sub-typing checks to succeed
* The AST JSON encoder will now stringify infinity and NaN according to the JSON5 spec using the tokens `Infinity`, `-Infinity`, and `NaN`.
* Improve autocompletion of table keys if the type of that key is a union of string singletons.
This is useful in particular if redefine `LUAI_MAXCSTACK` to a higher
value than the current one (8000).
Ie. passing `-D LUAI_MAXCSTACK=1000000` would not work as overlaps with
`LUA_REGISTRYINDEX` and below.
* Type mismatch errors now mention if unification failed in covariant or
invariant context, to explain why sometimes derived class can't be
converted to base class or why `T` can't be converted into `T?` and so
on
* Class type indexing is no longer an error in non-strict mode (still an
error in strict mode)
* Fixed cyclic type packs not being displayed in the type
* Added an error when unrelated types are compared with `==`/`~=`
* Fixed false positive errors involving sub-type tests an `never` type
* Fixed miscompilation of multiple assignment statements (Fixes
https://github.com/Roblox/luau/issues/754)
* Type inference stability improvements
Github fails to find clang++-10.
Since we install llvm without a specific version number, we shouldn't
use clang++-10 with a version number.
I tried installing llvm-10, but that package is not available on github
(any more?).
Currently, the metatable of a class type var is not correctly checked to
see if it is callable (i.e. has a `__call` metatable).
We resolve this issue by checking the metatable in `checkCallOverload`
Fixes#756
Co-authored-by: vegorov-rbx <75688451+vegorov-rbx@users.noreply.github.com>
Closes#631
Performs a "two pass" approach, where we first call `prototype` on the
class definition.
The prototype phase checks for errors and creates a base CTV for the
class, which other types can then reference.
The second `check` phase fills it out with all the defined
properties/methods
Co-authored-by: vegorov-rbx <75688451+vegorov-rbx@users.noreply.github.com>
String interpolation autocomplete was not working and was just using
default autocomplete. This fixes it so that inside a string it is
treated as normal, and inside an expression it suggests expression level
autocomplete.
Also fixes the range, which was previously just the first lexeme.
* Type inference of `a and b` and `a or b` has been improved (Fixes
https://github.com/Roblox/luau/issues/730)
* Improved error message when `for ... in x` loop iterates over a value
that could be 'nil'
* Return type of `next` not includes 'nil' (Fixes
https://github.com/Roblox/luau/issues/706)
* Improved type inference of `string` type
* Luau library table type names are now reported as `typeof(string)`/etc
instead of just `string` which was misleading
* Added parsing error when optional type alias type parameter wasn't
provided after `=` token
* Improved tagged union type refinement in conditional expressions, type
in `else` branch should no longer include previously handled union
options
* Reduce the stack utilization of type checking.
* Improve the error message that's reported when a delimiting comma is
missing from a table literal. eg
```lua
local t = {
first = 1
second = 2
}```
* https://github.com/Roblox/luau/pull/719
* Improved `Failed to unify type packs` error message to be reported as
`Type pack 'X' could not be converted into 'Y'`
* https://github.com/Roblox/luau/pull/722
* 1% reduction in executed instruction count by removing a check in fast
call dispatch
* Additional fixes to reported error location of OOM errors in VM
* Improve `math.sqrt`, `math.floor` and `math.ceil` performance on
additional compilers and platforms (1-2% geomean improvement including
8-9% on math-cordic)
* All thrown exceptions by Luau analysis are derived from
`Luau::InternalCompilerError`
* When a call site has fewer arguments than required, error now reports
the location of the function name instead of the argument to the
function
* https://github.com/Roblox/luau/pull/724
* Fixed https://github.com/Roblox/luau/issues/725
Co-authored-by: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Co-authored-by: Andy Friesen <afriesen@roblox.com>
Right now `getDocumentationSymbol` on an overloaded class method or
table prop just gives the prop name, not prepended with `/overload/ +
toString(overload)`.
This causes the incorrect symbol to be used for `table.insert`,
`BrickColor.new`, `Color3.new` etc. (present in
https://raw.githubusercontent.com/MaximumADHD/Roblox-Client-Tracker/roblox/api-docs/en-us.json)
Co-authored-by: vegorov-rbx <75688451+vegorov-rbx@users.noreply.github.com>
* Support `["prop"]` syntax on class definitions in definition files.
(#704)
* Improve type checking performance for complex overloaded functions
* Fix rare cases of incorrect stack traces for out of memory errors at
runtime
Name the parameters used in `math` lib
This is mainly done to highlight the particular confusion for
`math.atan2`, where `y` comes before `x`, but this might not be
immediately obvious.
And then I added the rest of the names for consistency.
Note: I didn't add names to `math.random` as it's currently typed as
`(number?, number?) -> number`. Naming it `min` and `max` is technically
incorrect for the 1 argument version.
Maybe it should be typed as an intersection instead?
`Frontend.markDirty()` does not correctly mark reverse dependencies that
are not immediate as dirty.
This is because it would keep adding the reverse deps of `name` into the
queue to mark as dirty, instead of the reverse deps of `next`
Some classes have properties which are not valid identifiers (such as
https://create.roblox.com/docs/reference/engine/classes/Studio)
This adds support for the following syntax in definition files:
```lua
declare class Foo
["a property"]: string
end
```
Closes#702
We will now run luau with --codegen during benchmark runs and collect
the data into separate JSON. Note that we don't yet have the historical
data for these, which will be backfilled later.
This change adds codegen runs to coverage config and adds O2/codegen
testing to CI.
Note that we don't run O2 combinations in coverage - it's better that we
see gaps in O2 coverage in compiler tests, as these are valuable for
validating codegen intricacies that are difficult to see from
conformance tests passing/failing.
* Reoptimized math.min/max/bit32 builtins assuming at least 2 arguments are used (1-2% lift on some benchmarks)
* Type errors that mention function types no longer have redundant parenthesis around return type
* Luau REPL now supports --compile=remarks which displays the source code with optimization remarks embedded as comments
* Builtin calls are slightly faster when called with 1-2 arguments (~1% improvement in some benchmarks)
