Use `@` syntax to escape `_` when used as an identifier.
Remove the stage1 astgen prohibition against assigning from `_`
Note: there a few stage1 bugs preventing `_` from being used as an identifier
for a local variable or function parameter; these will be fixed by stage2.
They are unlikely to arise in real C code since identifiers starting with
underscore are reserved for the implementation.
For stage1 ZIR instructions and stage1 AIR instructions, the instruction
op code was taking up 8 bytes due to padding even though it only needed
1 byte. This commit reduces the ref_count field from uint32_t to
uint16_t because the code only really cares if instructions are
referenced at all, not how many times they are referenced. With the
ref_count field reduced to uint16_t the uint8_t op code is now placed in
the freed up space.
Empirically, this saves 382 MiB of peak RAM usage when building the
self-hosted compiler, which is a reduction of 5%. Consequently this
resulted in a 3% reduction of cache-misses when building the self-hosted
compiler.
This was @SpexGuy's idea, committed by me because we tested it on my
computer.
Hashing, equality checking, and expanding lazy values were not
inspecting the is_comptime field of structs, causing incorrect behavior
for tuples. When looking at a comptime value of a struct, if the
is_comptime field is true, the value must be learned from the type
rather than the value.
When putting ZigValues into a hash map. The hash of a lazy value
and a fully resolved value must equal, and so we must resolve
the lazy values prior. The hash function asserts that none of
the values are lazy.
This commit intentions to have no functional changes. The only purpose
is to delete the struct IrInst, which is the common base struct that
both IrInstSrc (ZIR) and IrInstGen (AIR) instructions embed.
This untangles stage1 ZIR and AIR memory layout, paving the way for a
following commit to reduce memory usage.
It now displays the byte with proper printability handling. This makes
the relevant compile error test case no longer a regression in quality
from stage1 to stage2.
One more step towards lowering the memory footprint of stage1. This flag
was hiding in padding but now that it is gone we can re-arrange the
memory layout more easily.
* AstGen: implement "unreachable code" error for blocks. This works at
the statement level.
* stage1: remove the "unreachable code" error implementation, which
means removing the `is_gen` field from IrInstSrc. This is one small
step towards a smaller memory footprint for stage1. The benefits
won't be realized until a future commit because this flag took
advantage of padding.
There may be a regression here with "union has no associated enum"
error, and there is a regression with the following code:
```zig
const a = noreturn;
```
A future commit will address these regressions.
This breaking change disambiguates between overriding the lib dir when
performing an installation with the Zig Build System, and overriding the
lib dir that the Zig installation itself uses.
* stage1 backend allows configuring the uwtables function attr
via a flag rather than its own logic.
* stage2 defaults to enabling uwtable attr when
linking libunwind, or always on windows
* stage2 makes link_eh_frame_hdr true automatically if uwtable
attr is set to be on for zig functions
* CLI: add -funwind-tables and -fno-unwind-tables to allow the user to
override the defaults.
* hook it up to `zig cc`
closes#9046
closes#9034
These options were listed under the
"Debug Options (Zig Compiler Development)" heading. Anything in this
section should be considered unstable and can be modified at any time
at any developer's discretion.
This small change makes working with tuple types much easier, allowing
the use of anonymous (eg. obtained with meta.ArgsTuple) tuples in more
places without the need for specifying each (quoted!) field name in the
initializer.
Bitcast the pointer and operands to integer types having the same size,
working around LLVM inability to lower a LL/SC operation when the
operands have floating-point types (and are reasonably sized).
Closes#4457
Currently, stage1 runs astgen for every comptime function call,
resulting in identifier strings being allocated multiple times,
wasting memory. As a workaround until the code is adjusted to
make astgen run only once per source node, we memoize the
result into the AST.
* Rename `ir_gen_*` to `astgen_*`
- Oops, meant to do this in a separate commit. My bad.
* tokenizer: avoid using designated initializer syntax.
MSVC does not support it.
