So far it's supported by the LLVM backend only. I recommend for the
other backends to wait for the resolution of #10761 before adding
support for this feature.
ZIR instructions updated: atomic_load, atomic_rmw, atomic_store, cmpxchg
These no longer construct a pointer type as the result location. This
solves a TODO that was preventing the pointer from possibly being
volatile, as well as properly handling allowzero and addrspace.
It also allows the pointer to be over-aligned, which may be needed
depending on the target. As a consequence, the element type needs to be
communicated in the ZIR. This is done by strategically making one of the
operands be ResultLoc.ty instead of ResultLoc.coerced_ty if possible, or
otherwise explicitly adding elem_type into the ZIR encoding, such as in
the case of atomic_load.
The pointer type of atomic operations is now checked in Sema by coercing
it to an expected pointer type, that maybe over-aligned according to
target requirements.
Together with the previous commit, Zig now has smaller alignment for
large integers, depending on the target, and yet still has type safety
for atomic operations that specially require higher alignment.
* outputs can have names and be referenced with template replacements
the same as inputs.
* fix print_air.zig not decoding correctly.
* LLVM backend: use a table for template names for simplicity
Instead of doing heterogeneous comparison at comptime. This makes the
following test pass (as it already does for stage1):
```zig
test {
const x: f64 = 12.34;
expect(x == 12.34);
}
```
There is already behavior test coverage for this, however, other bugs in
`std.fmt.parseFloat` are masking the failures.
From a language specification perspective, this makes sense because it
makes comptime comparisons with comptime_float work the same way they
work with runtime comparisons.
* Sema: Correctly determine whether array_cat lhs and rhs are single ptrs
Many-pointers are also not single-pointers and wouldn't be considered
here. This commit makes the conditions use the appropriately-named
isSinglePointer instead.
* Sema: Correctly obtain ArrayInfo for many-pointer concatenation
Many-pointers at comptime have a known size like slices and can be used
in array concatenation. This fixes a stage1 regression.
* test: Add comptime manyptr concatenation test
Co-authored-by: sin-ack <sin-ack@users.noreply.github.com>
The reason for having `@tan` is that we already have `@sin` and `@cos`
because some targets have machine code instructions for them, but in the
case that the implementation needs to go into compiler-rt, sin, cos, and
tan all share a common dependency which includes a table of data. To
avoid duplicating this table of data, we promote tan to become a builtin
alongside sin and cos.
ZIR: The tag enum is at capacity so this commit moves
`field_call_bind_named` to be `extended`. I measured this as one of
the least used tags in the zig codebase.
Fix libc math suffix for `f32` being wrong in both stage1 and stage2.
stage1: add missing libc prefix for float functions.
* unify the logic for exporting math functions from compiler-rt,
with the appropriate suffixes and prefixes.
- add all missing f128 and f80 exports. Functions with missing
implementations call other functions and have TODO comments.
- also add f16 functions
* move math functions from freestanding libc to compiler-rt (#7265)
* enable all the f128 and f80 code in the stage2 compiler and behavior
tests (#11161).
* update std lib to use builtins rather than `std.math`.
Rather than allocating Decl objects with an Allocator, we instead allocate
them with a SegmentedList. This provides four advantages:
* Stable memory so that one thread can access a Decl object while another
thread allocates additional Decl objects from this list.
* It allows us to use u32 indexes to reference Decl objects rather than
pointers, saving memory in Type, Value, and dependency sets.
* Using integers to reference Decl objects rather than pointers makes
serialization trivial.
* It provides a unique integer to be used for anonymous symbol names,
avoiding multi-threaded contention on an atomic counter.
* The `@bitCast` workaround is removed in favor of `@ptrCast` properly
doing element casting for slice element types. This required an
enhancement both to stage1 and stage2.
* stage1 incorrectly accepts `.{}` instead of `{}`. stage2 code that
abused this is fixed.
* Make some parameters comptime to support functions in switch
expressions (as opposed to making them function pointers).
* Avoid relying on local temporaries being mutable.
* Workarounds for when stage1 and stage2 disagree on function pointer
types.
* Workaround recursive formatting bug with a `@panic("TODO")`.
* Remove unreachable `else` prongs for some inferred error sets.
All in effort towards #89.
The problem was that types of non-anytype parameters were being included
as part of the check to see if generic function instantiations were
equal. Now, Module.Fn additionally stores the information for whether each
parameter is anytype or not. `generic_poison` cannot be used to signal
this because the type is still needed for comptime arguments; in such
case the type will not be present in the newly generated function
prototype.
This presented one additional challenge: we need to compare equality of
two values where one of them is post-coercion and the other is not. So
we make some minor adjustments to `Type.eql` to support this. I think
this small complexity tradeoff is worth it because it means the compiler
does much less work on the hot path that a generic function is called
and there is already an existing matching instantiation.
closes#11146
This causes false positive "foo depends on itself" errors. Prior to some
recent enhancements, this type resolution was needed, however, we now
have a more sophisticated type resolution mechanism that fully
resolves types for the backend, but only after the Decl is fully
analyzed, avoiding dependency loops.
Previously, Zig would try to generate a function whose type contained
structs or unions which had not been fully resolved due to circular
dependency errors. With this commit, `resolveTypeFully` will be sure to
return `error.AnalysisFail` even in this scenario, leading to proper
display of compilation errors instead of a crash.
* If more than one error is reported for the same Decl, the first error
message is kept and the second one discarded.
* Prevent functions from being sent to codegen backends if there were
any errors resolving any of their parameter types or return type.
There was a simple missing check of adding an inferred error set to
itself, in which case we should not try to mutate the hash map while
iterating over it.
Instead, use ResultLoc.none to allow for the expression type to be
inferred [^1]. This effectively moves the type coercion to Sema, in
order to turn comptime values into usable values for the backends to
consume. Right now the coercion is applies as comptime_int -> usize and
comptime_float -> f64, as an arbitrary choice.
[^1]: 9f25c8140c/src/AstGen.zig (L207-L208)
An assembly expression in a comptime block is legal Zig in the case of
global assembly [^1]. Instead of unconditionally asserting that the
expression lives in a runtime block, here we assert that if the
expression lives in a comptime block it must be outside of function
scope.
[^1]: https://ziglang.org/documentation/0.9.1/#Global-Assembly
* Sema: store the precomputed monomorphed_funcs hash inside Module.Fn.
This is important because it may be accessed when resizing monomorphed_funcs
while this Fn has already been added to the set, but does not have the
owner_decl, comptime_args, or other fields populated yet.
* Sema: in `analyzeIsNonErr`, take advantage of the AIR tag being
`wrap_errunion_payload` to infer that `is_non_err` is comptime true
without performing any error set resolution.
- Also add some code to check for empty inferred error sets in this
function. If necessary we do resolve the inferred error set.
* Sema: queue full type resolution of payload type when
`wrap_errunion_payload` AIR instruction is emitted. This ensures the
backend may check the alignment of it.
* Sema: resolveTypeFully now additionally resolves comptime-only
status.
closes#11306
This commit introduces a new AIR instruction `cmp_lt_errors_len`. It's
specific to this use case for two reasons:
* The total number of errors is not stable during semantic analysis; it
can only be reliably checked when flush() is called. So the backend
that is lowering the instruction must emit a relocation of some kind
and then populate it during flush().
* The fewer AIR instructions in memory, the better for compiler
performance, so we squish complex meanings into AIR tags without
hesitation.
The instruction is implemented only in the LLVM backend so far. It does
this by creating a simple function which is gutted and re-populated
with each flush().
AstGen now uses ResultLoc.coerced_ty for `@intToError` and Sema does the
coercion.
* In semaStructFields and semaUnionFields we return error.GenericPoison
if one of the field types ends up being generic poison.
- This requires handling function calls and function types taking
this into account when calling `typeRequiresComptime` on the return
type.
* Unrelated: I noticed using Valgrind that struct reification did not
populate the `known_opv` field. After fixing it, the behavior tests
run Valgrind-clean.
* ZIR: use `@ptrCast` to cast between slices instead of exploiting
the fact that stage1 incorrectly allows `@bitCast` between slices.
- A future enhancement will make Zig support `@ptrCast` to directly
cast between slices.
To no longer set the error code to undefined. This fixes the problem
where an undefined single-item pointer coerced to an error union of a
slice set the whole thing to undefined even though the sub-coercion to
the slice would have produced a defined value.