luau/Analysis/include/Luau/Scope.h
vegorov-rbx 140e5a1495
Sync to upstream/release/566 (#853)
* Fixed incorrect lexeme generated for string parts in the middle of an
interpolated string (Fixes https://github.com/Roblox/luau/issues/744)
* DeprecatedApi lint can report some issues without type inference
information
* Fixed performance of autocomplete requests when suggestions have large
intersection types (Solves
https://github.com/Roblox/luau/discussions/847)
* Marked `table.getn`/`foreach`/`foreachi` as deprecated ([RFC:
Deprecate
table.getn/foreach/foreachi](https://github.com/Roblox/luau/blob/master/rfcs/deprecate-table-getn-foreach.md))
* With -O2 optimization level, we now optimize builtin calls based on
known argument/return count.
Note that this change can be observable if `getfenv/setfenv` is used to
substitute a builtin, especially if arity is different.
Fastcall heavy tests show a 1-2% improvement.
* Luau can now be built with clang-cl (Fixes
https://github.com/Roblox/luau/issues/736)

We also made many improvements to our experimental components.

For our new type solver:
* Overhauled data flow analysis system, fixed issues with 'repeat'
loops, global variables and type annotations
* Type refinements now work on generic table indexing with a string
literal
* Type refinements will properly track potentially 'nil' values (like
t[x] for a missing key) and their further refinements
* Internal top table type is now isomorphic to `{}` which fixes issues
when `typeof(v) == 'table'` type refinement is handled
* References to non-existent types in type annotations no longer resolve
to 'error' type like in old solver
* Improved handling of class unions in property access expressions
* Fixed default type packs
* Unsealed tables can now have metatables
* Restored expected types for function arguments

And for native code generation:
* Added min and max IR instructions mapping to vminsd/vmaxsd on x64
* We now speculatively extract direct execution fast-paths based on
expected types of expressions which provides better optimization
opportunities inside a single basic block
* Translated existing math fastcalls to IR form to improve tag guard
removal and constant propagation
2023-03-03 12:21:14 -08:00

87 lines
3.2 KiB
C++

// This file is part of the Luau programming language and is licensed under MIT License; see LICENSE.txt for details
#pragma once
#include "Luau/Def.h"
#include "Luau/Location.h"
#include "Luau/NotNull.h"
#include "Luau/Type.h"
#include <unordered_map>
#include <optional>
#include <memory>
namespace Luau
{
struct Scope;
using ScopePtr = std::shared_ptr<Scope>;
struct Binding
{
TypeId typeId;
Location location;
bool deprecated = false;
std::string deprecatedSuggestion;
std::optional<std::string> documentationSymbol;
};
struct Scope
{
explicit Scope(TypePackId returnType); // root scope
explicit Scope(const ScopePtr& parent, int subLevel = 0); // child scope. Parent must not be nullptr.
const ScopePtr parent; // null for the root
// All the children of this scope.
std::vector<NotNull<Scope>> children;
std::unordered_map<Symbol, Binding> bindings;
TypePackId returnType;
std::optional<TypePackId> varargPack;
TypeLevel level;
std::unordered_map<Name, TypeFun> exportedTypeBindings;
std::unordered_map<Name, TypeFun> privateTypeBindings;
std::unordered_map<Name, Location> typeAliasLocations;
std::unordered_map<Name, Location> typeAliasNameLocations;
std::unordered_map<Name, ModuleName> importedModules; // Mapping from the name in the require statement to the internal moduleName.
std::unordered_map<Name, std::unordered_map<Name, TypeFun>> importedTypeBindings;
DenseHashSet<Name> builtinTypeNames{""};
void addBuiltinTypeBinding(const Name& name, const TypeFun& tyFun);
std::optional<TypeId> lookup(Symbol sym) const;
std::optional<TypeId> lookup(DefId def) const;
std::optional<std::pair<Binding*, Scope*>> lookupEx(Symbol sym);
std::optional<TypeFun> lookupType(const Name& name);
std::optional<TypeFun> lookupImportedType(const Name& moduleAlias, const Name& name);
std::unordered_map<Name, TypePackId> privateTypePackBindings;
std::optional<TypePackId> lookupPack(const Name& name);
// WARNING: This function linearly scans for a string key of equal value! It is thus O(n**2)
std::optional<Binding> linearSearchForBinding(const std::string& name, bool traverseScopeChain = true) const;
RefinementMap refinements;
DenseHashMap<const Def*, TypeId> dcrRefinements{nullptr};
// For mutually recursive type aliases, it's important that
// they use the same types for the same names.
// For instance, in `type Tree<T> { data: T, children: Forest<T> } type Forest<T> = {Tree<T>}`
// we need that the generic type `T` in both cases is the same, so we use a cache.
std::unordered_map<Name, TypeId> typeAliasTypeParameters;
std::unordered_map<Name, TypePackId> typeAliasTypePackParameters;
};
// Returns true iff the left scope encloses the right scope. A Scope* equal to
// nullptr is considered to be the outermost-possible scope.
bool subsumesStrict(Scope* left, Scope* right);
// Returns true if the left scope encloses the right scope, or if they are the
// same scope. As in subsumesStrict(), nullptr is considered to be the
// outermost-possible scope.
bool subsumes(Scope* left, Scope* right);
} // namespace Luau