The `Value.eql` function has to test for value equality *as-if* the lhs
value parameter is coerced into the type of the rhs. For tagged unions,
there was a problematic case when the lhs was an anonymous struct,
because in such case the value is empty_struct_value and the type
contains all the value information. But the only type available in the
function was the rhs type.
So the fix involved making `Value.eqlAdvanced` also accept the lhs type,
and then enhancing the logic to handle the case of the `.anon_struct` tag.
closes#12418
Tests run locally:
* test-behavior
* test-cases
Previously, the logic for analyzing coerce_result_ptr would generate
invalid bitcast instructions which did not include coercion logic, such
as optional wrapping, resulting in miscompilations.
Now, the logic of resolve_inferred_alloc goes back over all the
placeholders inserted by coerce_result_ptr, and replaces them with logic
doing the proper coercions.
Closes#12045
* Sema: implement comptime bitcast of f80 with integer-like types
bitwise rather than taking a round trip through memory layout.
* Type: introduce `isAbiInt`.
* Value: comptime memory write of f80 writes 0 bytes for padding
instead of leaving the memory uninitialized.
* Value: floatReadFromMemory has a more general implementation, checking
the endianness rather than checking for specific architectures.
This fixes behavior test failures occurring on MIPS.
Zig guarantees the memory layout of f16, f32, f64, f80, and f128 which
means for generic function purposes, values of these types need to be
compared on the basis of their bits in memory. This means nan-packing
can be used with generic functions, for example.
For comptime_float, the sign is observable, whether it is nan is
observable, but not any more kinds of bit patterns are observable.
This fixes the std.fmt tests that check printing "-nan".
This commit does not change any behavior, but changes the type of
the runtime_index field from u32 to a non-exhaustive enum. This allows
us to put `std.math.maxInt(u32)` only in the enum type definition and
give it an official meaning.
This is a temporary addition to stage2 in order to match stage1 behavior,
however the end-game once the lang spec is settled will be to use a global
InternPool for comptime memoized objects, making this behavior consistent
across all types, not only string literals. Or, we might decide to not
guarantee string literals to have equal comptime pointers, in which case
this commit can be reverted.
Motivation: the behavior test that is now passing.
The main change in this commit is introducing `Type.abiSizeAdvanced`,
`Value.Tag.lazy_size`, and adjusting `Sema.zirSizeOf` to take advantage
of these.
However, the bulk of lines changed in this commit ended up being moving
logic from value.zig and type.zig into Sema.zig. This logic had no
business being in Type/Value as it was only called from a Sema context,
and we need access to the Sema context for error reporting when a lazy
Value is resolved.
Also worth mentioning is that I bumped up the comptime `@floatToInt`
implementation from using f64 to f128.
When handling the `negate` ZIR instruction, Zig now checks for a
comptime operand and handles it as a special case rather than lowering
it as `0 - x` so that the expression `-x` where `x` is a floating point
value known at compile-time, will get the negative zero bitwise
representation.
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 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
Although lazy_align is a different tag than integer values, it needs to
be hashed and equality-tested as if it were a simple integer. Otherwise
our basic data structure guarantees fall apart.
* AstGen: restore the param_type ZIR instruction and pass it to the
expression for function call arguments. This does not solve the
problem for generic function parameters, but it catches stage2 up to
stage1 which also does not solve the problem for generic function
parameters.
- Most of the enhancements in this commit will still be needed for a
more sophisticated further improvement to handle generic function
types.
- In Sema, handling of `as` coercion recognizes the `var_args_param`
Type Tag and passes the operand through doing no coercion.
- That was the last ZIR tag and we are now using all 256 ZIR tags.
* AstGen: array init and struct init expressions use the anon form even
when the result location has a type. Prevents the type system
incorrectly believing, for example, that a tuple is actually an array
when the result location is a param_type of a function with `anytype`
parameter.
* Sema: add missing coercion in `unionInit` to coerce the init to the
corresponding union field type.
* `Value.fieldValue` now takes a type and does not take an allocator.
closes#11293
After this commit, stage2 passes all the parser tests.
