* introduce std.ArrayListUnmanaged for when you have the allocator
stored elsewhere
* move std.heap.ArenaAllocator implementation to its own file. extract
the main state into std.heap.ArenaAllocator.State, which can be
stored as an alternative to storing the entire ArenaAllocator, saving
24 bytes per ArenaAllocator on 64 bit targets.
* std.LinkedList.Node pointer field now defaults to being null
initialized.
* Rework self-hosted compiler Package API
* Delete almost all the bitrotted self-hosted compiler code. The only bit
rotted code left is in main.zig and compilation.zig
* Add call instruction to ZIR
* self-hosted compiler ir API and link API are reworked to support
a long-running compiler that incrementally updates declarations
* Introduce the concept of scopes to ZIR semantic analysis
* ZIR text format supports referencing named decls that are declared
later in the file
* Figure out how memory management works for the long-running compiler
and incremental compilation. The main roots are top level
declarations. There is a table of decls. The key is a cryptographic
hash of the fully qualified decl name. Each decl has an arena
allocator where all of the memory related to that decl is stored.
Each code block has its own arena allocator for the lifetime of
the block. Values that want to survive when going out of scope in
a block must get copied into the outer block. Finally, values must
get copied into the Decl arena to be long-lived.
* Delete the unused MemoryCell struct. Instead, comptime pointers are
based on references to Decl structs.
* Figure out how caching works. Each Decl will store a set of other
Decls which must be recompiled when it changes.
This branch is still work-in-progress; this commit breaks the build.
Now there are 3 types:
* std.math.big.int.Const
- the memory is immutable, only stores limbs and is_positive
- all methods operating on constant data go here
* std.math.big.int.Mutable
- the memory is mutable, stores capacity in addition to limbs and
is_positive
- methods here have some Mutable parameters and some Const
parameters. These methods expect callers to pre-calculate the
amount of resources required, and asserts that the resources are
available.
* std.math.big.int.Managed
- the memory is mutable and additionally stores an allocator.
- methods here perform the resource calculations for the programmer.
- this is the high level abstraction from before
Each of these 3 types can be converted to the other ones.
You can see the use case for this in the self-hosted compiler, where we
only store limbs, and construct the big ints as needed.
This gets rid of the hack where the allocator was optional and the
notion of "fixed" versions of the struct. Such things are now modeled
with the `big.int.Const` type.
This new name (and the fact that it is a function returning a type) will
make it more clear which use cases are better suited for ArrayList and
which are better suited for ArrayListSentineled.
Also for consistency with ArrayList,
* `append` => `appendSlice`
* `appendByte` => `append`
Thanks daurnimator for pointing out the confusion of std.Buffer.
this also deletes C string literals from the language, and then makes
the std lib changes and compiler changes necessary to get the behavior
tests and std lib tests passing again.
This effectively takes one-bit from the length field and uses it as the
sign bit. It reduces the size of an Int from 40 bits to 32 bits on a
64-bit arch.
This also reduces std.Rational from 80 bits to 64 bits.
`std.mem.Allocator.createOne` is renamed to `std.mem.Allocator.create`.
The problem with the previous API is that even after copy elision,
the initalization value passed as a parameter would always be a copy.
With the new API, once copy elision is done, initialization
functions can directly initialize allocated memory in place.
Related:
* #1872
* #1873