The memory layout for ZIR instructions is completely reworked. See
zir.zig for those changes. Some new types:
* `zir.Code`: a "finished" set of ZIR instructions. Instead of allocating
each instruction independently, there is now a Tag and 8 bytes of
data available for all ZIR instructions. Small instructions fit
within these 8 bytes; larger ones use 4 bytes for an index into
`extra`. There is also `string_bytes` so that we can have 4 byte
references to strings. `zir.Inst.Tag` describes how to interpret
those 8 bytes of data.
- This is shared by all `Block` scopes.
* `Module.WipZirCode`: represents an in-progress `zir.Code`. In this
structure, the arrays are mutable, and get resized as we add/delete
things. There is extra state to keep track of things. This struct is
stored on the stack. Once it is finished, it produces an immutable
`zir.Code`, which will remain on the heap for the duration of a
function's existence.
- This is shared by all `GenZir` scopes.
* `Sema`: represents in-progress semantic analysis of a `zir.Code`.
This data is stored on the stack and is shared among all `Block`
scopes. It is now the main "self" argument to everything in the file
that was previously named `zir_sema.zig`.
Additionally, I moved some logic that was in `Module` into here.
`Module.Fn` now stores its parameter names inside the `zir.Code`,
instead of inside ZIR instructions. When the TZIR memory layout
reworking time comes, codegen will be able to reference this data
directly instead of duplicating it.
astgen.zig is (so far) almost entirely untouched, but nearly all of it
will need to be reworked to adhere to this new memory layout structure.
I have no benchmarks to report yet, as I am still working through
compile errors and fixing various things that I broke in this branch.
Overhaul of Source Locations:
Previously we used `usize` everywhere to mean byte offset, but sometimes
also mean other stuff. This was error prone and also made us do
unnecessary work, and store unnecessary bytes in memory.
Now there are more types involved into source locations, and more ways
to describe a source location.
* AllErrors.Message: embrace the assumption that files always have less
than 2 << 32 bytes.
* SrcLoc gets more complicated, to model more complicated source
locations.
* Introduce LazySrcLoc, which can model interesting source locations
with very little stored state. Useful for avoiding doing unnecessary
work when no compile errors occur.
Also, previously, we had `src: usize` on every ZIR instruction. This is
no longer the case. Each instruction now determines whether it even cares
about source location, and if so, how that source location is stored.
This requires more careful work inside `Sema`, but it results in fewer
bytes stored on the heap, without compromising accuracy and power of
compile error messages.
Miscellaneous:
* std.zig: string literals have more helpful result values for
reporting errors. There is now a lower level API and a higher level
API.
- side note: I noticed that the string literal logic needs some love.
There is some unnecessarily hacky code there.
* cut & pasted some TZIR logic that was in zir.zig to ir.zig. This
probably broke stuff and needs to get fixed.
* Removed type/Enum.zig, type/Union.zig, and type/Struct.zig. I don't
think this quite how this code will be organized. Need some more
careful planning about how to implement structs, unions, enums. They
need to be independent Decls, just like a top level function.
The main realization here was that getting rid of the early returns
in renderWhile() and rewriting the logic into a mostly unified execution
path took things from ~200 lines to ~100 lines and improved consistency
by deduplicating code.
Also add several test cases and fix a few issues along the way:
Fixes https://github.com/ziglang/zig/issues/6114
Fixes https://github.com/ziglang/zig/issues/8022
Add failing testcase to reproduce issue 8088
Tidy up renderWhile(), factoring out renderWhilePayload()
Ensure correct newline is used before 'then' token in while/for/if
Handle indents for 'if' inside 'for' or 'while'
Stop special-casing 'if' compared to 'for' and 'while'
fix drivers: zig {cc,c++}
- `-dynamiclib` is an alias to `-shared`
- associate `-dynamiclib` with zig `.shared` semantics
fix drivers: zig {cc,c++,build-lib,build-exe}
- use `-dynamic` for {exe,dylib}
- for dylib this fixes a regression
- for exe this replaces incorrect use of `-static`
A warning is emitted when using the debug option --debug-log when the compiler
was not compiled using the build option -Dlog. Additionnaly, the scopes are not
added to log_scopes as they have no effect.
Previously, there was an option ZIG_PREFER_LLVM_CONFIG which would
override the default of not using llvm-config when cross compiling.
That option is now removed in favor of the more powerful
ZIG_USE_LLVM_CONFIG which defaults to OFF for cross compiling and ON for
native compilation. The option overrides the default.
This will be used in zig-bootstrap to improve support for native builds.
liburing commit: 1bafb3ce5f
As stated in the liburing commit message, this fixes a regression,
reverting code that was added specutively to avoid a syscall in some
cases.
The current implementation of the target C ABI rules is hopelessly bad,
let's tack some more rules on top in order to prevent some
miscompilations.
Truth to be told the same rule should be applied also to parameters, but
I really can't stand stage1.
The modification to the grammar in the comment is in line with the
grammar in the zig-spec repo.
Note: checking if the previous token is a colon is insufficent to tell
if a block has a label, the identifier must be checked for as well. This
can be seen in sentinel terminated slicing: `foo[0..1:{}]`
