This removes the two original implementations in favour of the single
generic one based on the Algorithm type. Previously we had three, very
similar implementations which was somewhat confusing when knowing what
one should actually be used.
The previous polynomials all have equivalent variants available when
using the Algorithm type.
This flips things around such that std/hash/crc.zig is generated
by the catalog-based generation tool, and the real code that used
to be in that file is moved out to std/hash/crc/impl.zig. The
generated tests are moved to std/hash/crc/test.zig. By going this
route, we eliminate the need for usingnamespace without changing
anything for callers of these interfaces. The Crc32 tests are
simply added to the fixed part of the generated output and
compactified a bit.
This was the second-to-last usage of usingnamespace left in std.
In general, I don't like the idea of std.meta.trait, and so I am
providing some guidance by deleting the entire namespace from the
standard library and compiler codebase.
My main criticism is that it's overcomplicated machinery that bloats
compile times and is ultimately unnecessary given the existence of Zig's
strong type system and reference traces.
Users who want this can create a third party package that provides this
functionality.
closes#18051
Use inline to vastly simplify the exposed API. This allows a
comptime-known endian parameter to be propogated, making extra functions
for a specific endianness completely unnecessary.
This reverts commit 0c99ba1eab63865592bb084feb271cd4e4b0357e, reversing
changes made to 5f92b070bf284f1493b1b5d433dd3adde2f46727.
This caused a CI failure when it landed in master branch due to a
128-bit `@byteSwap` in std.mem.
XXH3 is the faster alternative to XXH64 which utilizes SIMD
when hashing large chunks of memory and similar mixing to
WyHash (64x64 -> 128 mul) for smaller inputs.
Co-authored-by: Reixcon226 <87927264+Rexicon226@users.noreply.github.com>
---------
Co-authored-by: kprotty <kbutcher6200@gmail.com>
Not all hashes are added just yet as these need to be generated manually
from reference implementations as they are not included by default in
smhasher.
Improvements for xxHash performance, both on small keys as well as large slices.
* std.hash: make benchmarks consistent for xxhash
There is some odd behaviour in the timings for the XXHash benchmarks
introduced in 879f0b9, specifically the changes to the allocation in
benchmarkHash. The problem is somewhere in the difference between
9628243 and 9362d61 (these are commit that were force-pushed over but
can be found in PR #15917).
* std.hash: correctly calculate throughput in benchmark
* std.hash: add hashes per sec to small key output
* std.hash: add exact and small xxhash routines
* std.hash: add --small-only flag to benchmark
* std.hash.xxhash: extract stateless Accumulator type
* std.hash.xxhash: cleanup hash() and improve small key perf
* std.hash.xxhash: port xxhash64 changes to xxhash32
* std.hash: change benchmark --small-only flag to --include-array
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
Instead of carrying an optimized version of wyhash in the compiler for
small keys, put it into the std lib where it belongs.
...except it does not match the official test cases. This will need to
be fixed before merging into master. This is an extremely
contributor-friendly task.
Related issue: #15916
This commit removes the `field_call_bind` and `field_call_bind_named` ZIR
instructions, replacing them with a `field_call` instruction which does the bind
and call in one.
`field_call_bind` is an unfortunate instruction. It's tied into one very
specific usage pattern - its result can only be used as a callee. This means
that it creates a value of a "pseudo-type" of sorts, `bound_fn` - this type used
to exist in Zig, but now we just hide it from the user and have AstGen ensure
it's only used in one way. This is quite silly - `Type` and `Value` should, as
much as possible, reflect real Zig types and values.
It makes sense to instead encode the `a.b()` syntax as its own ZIR instruction,
so that's what we do here. This commit introduces a new instruction,
`field_call`. It's like `call`, but rather than a callee ref, it contains a ref
to the object pointer (`&a` in `a.b()`) and the string field name (`b`). This
eliminates `bound_fn` from the language, and slightly decreases the size of
generated ZIR - stats below.
This commit does remove a few usages which used to be allowed:
- `@field(a, "b")()`
- `@call(.auto, a.b, .{})`
- `@call(.auto, @field(a, "b"), .{})`
These forms used to work just like `a.b()`, but are no longer allowed. I believe
this is the correct choice for a few reasons:
- `a.b()` is a purely *syntactic* form; for instance, `(a.b)()` is not valid.
This means it is *not* inconsistent to not allow it in these cases; the
special case here isn't "a field access as a callee", but rather this exact
syntactic form.
- The second argument to `@call` looks much more visually distinct from the
callee in standard call syntax. To me, this makes it seem strange for that
argument to not work like a normal expression in this context.
- A more practical argument: it's confusing! `@field` and `@call` are used in
very different contexts to standard function calls: the former normally hints
at some comptime machinery, and the latter that you want more precise control
over parts of a function call. In these contexts, you don't want implicit
arguments adding extra confusion: you want to be very explicit about what
you're doing.
Lastly, some stats. I mentioned before that this change slightly reduces the
size of ZIR - this is due to two instructions (`field_call_bind` then `call`)
being replaced with one (`field_call`). Here are some numbers:
+--------------+----------+----------+--------+
| File | Before | After | Change |
+--------------+----------+----------+--------+
| Sema.zig | 4.72M | 4.53M | -4% |
| AstGen.zig | 1.52M | 1.48M | -3% |
| hash_map.zig | 283.9K | 276.2K | -3% |
| math.zig | 312.6K | 305.3K | -2% |
+--------------+----------+----------+--------+
* Sema: upgrade operands to array pointers if possible when emitting
AIR.
* Implement safety checks for length mismatch and aliasing.
* AIR: make ptrtoint support slice operands. Implement in LLVM backend.
* C backend: implement new `@memset` semantics. `@memcpy` is not done
yet.
Now they use slices or array pointers with any element type instead of
requiring byte pointers.
This is a breaking enhancement to the language.
The safety check for overlapping pointers will be implemented in a
future commit.
closes#14040
