This reverts commit d48e4245b68bf25c7f41804a5012ac157a5ee546.
I have no idea why this is failing Drone CI, but in a branch, reverting
this commit solved the problem.
Instead use the standarized option for communicating the
zig compiler backend at comptime, which is `zig_backend`. This was
introduced in commit 1c24ef0d0b09a12a1fe98056f2fc04de78a82df3.
The ZIR instructions `switch_capture_else` and `switch_capture_ref` are
removed because they are not needed. Instead, the prong index is set to
max int for the special prong.
Else prong with error sets is not handled yet.
Adds a new behavior test because there was not a prior on to cover only
the capture value of else on a switch.
Previously, breaking from an outer block at comptime would result in
incorrect control flow. Now there is a mechanism, `error.ComptimeBreak`,
similar to `error.ComptimeReturn`, to send comptime control flow further
up the stack, to its matching block.
This commit also introduces a new log scope. To use it, pass
`--debug-log sema_zir` and you will see 1 line per ZIR instruction
semantically analyzed. This is useful when you want to understand what
comptime control flow is doing while debugging the compiler.
One more `switch` test case is passing.
* implement `genSetStack` for `ptr_stack_offset`
* handle `ptr_add`
* implement storing from register into pointer in register
* split alignment and array tests into those that pass on x86_64 and
those that do not
* pass more tests on x86_64
* Fix incorrect result when the first digit after the decimal point is not 0-9 - eg 0x0.ap0
* Fix compiler panic when the number starts with `0X` with a capital `X` - eg 0X0p0
* Fix compiler panic when the number has a decimal point immediately after `0x` - eg 0x.0p0
There is a mechanism to avoid redundant `as` ZIR instructions which is
to pass `ResultLoc.coerced_ty` instead of `ResultLoc.ty` when it is
known by AstGen that Sema will do the coercion.
This commit downgrades `coerced_ty` to `ty` when a result location
passes through an expression that branches, such as `if`, `switch`,
`while`, and `for`, causing the `as` ZIR instruction to be emitted.
This ensures that the type of a result location will be applied to, e.g.
a `comptime_int` on either side of a branch on a runtime condition.
It is the job of codegen backends to mark Decls that are referenced as
alive so that the frontend does not sweep them with the garbage. This
commit unifies the code between the backends with an added method on
Decl.
The implementation is more complete than before, switching on the Decl
val tag and recursing into sub-values.
As a result, two more array tests are passing.
Introduce `validate_array_init_comptime`, similar to
`validate_struct_init_comptime` introduced in
713d2a9b3883942491b40738245232680877cc66.
`zirValidateArrayInit` is improved to detect comptime array literals and
emit AIR accordingly. This code is very similar to the changes
introduced in that same commit for `zirValidateStructInit`.
The C backend needed some improvements to continue passing the same set
of tests:
* `resolveInst` for arrays now will add a local `static const` with the
array value and so then `elem_val` instructions reference that local.
It memoizes accesses using `value_map`, which is changed to use
`Air.Inst.Ref` as the key rather than `Air.Inst.Index`.
* This required a mechanism for writing to a "header" which is lines
that appear at the beginning of a function body, before everything
else.
* dbg_stmt output comments rather than `#line` directives.
TODO comment reproduced here:
We need to re-evaluate whether to emit these or not. If we naively emit
these directives, the output file will report bogus line numbers because
every newline after the #line directive adds one to the line.
We also don't print the filename yet, so the output is strictly unhelpful.
If we wanted to go this route, we would need to go all the way and not output
newlines until the next dbg_stmt occurs.
Perhaps an additional compilation option is in order?
`Value.elemValue` is improved to support `elem_ptr` values.
AIR:
* `array_elem_val` is now allowed to be used with a vector as the array
type.
* New instructions: splat, vector_init
AstGen:
* The splat ZIR instruction uses coerced_ty for the ResultLoc, avoiding
an unnecessary `as` instruction, since the coercion will be performed
in Sema.
* Builtins that accept vectors now ignore the type parameter. Comment
from this commit reproduced here:
The accepted proposal #6835 tells us to remove the type parameter from
these builtins. To stay source-compatible with stage1, we still observe
the parameter here, but we do not encode it into the ZIR. To implement
this proposal in stage2, only AstGen code will need to be changed.
Sema:
* `clz` and `ctz` ZIR instructions are now handled by the same function
which accept AIR tag and comptime eval function pointer to
differentiate.
* `@typeInfo` for vectors is implemented.
* `@splat` is implemented. It takes advantage of `Value.Tag.repeated` 😎
* `elemValue` is implemented for vectors, when the index is a scalar.
Handling a vector index is still TODO.
* Element-wise coercion is implemented for vectors. It could probably
be optimized a bit, but it is at least complete & correct.
* `Type.intInfo` supports vectors, returning int info for the element.
* `Value.ctz` initial implementation. Needs work.
* `Value.eql` is implemented for arrays and vectors.
LLVM backend:
* Implement vector support when lowering `array_elem_val`.
* Implement vector support when lowering `ctz` and `clz`.
* Implement `splat` and `vector_init`.
- This implements the float_to_int AIR instruction.
- Lowering a decl_ref to a slice was previously assumed to contain a pointer
to a slice, rather than an array. This is now fixed, making `@src()` work as well.
- Some preliminary work on 128bit integers have been done to find out what needs to be done
to implement 128bit arithmetic.
* stage2: put decls in different MachO sections
Use `getDeclVAddrWithReloc` when targeting MachO backend rather than
`getDeclVAddr` - this fn returns a zero vaddr and instead creates a
relocation on the linker side which will get automatically updated
whenever the target decl is moved in memory. This fn also records
a rebase of the target pointer so that its value is correctly slid
in presence of ASLR.
This commit enables `zig test` on x86_64-macos.
* stage2: fix output section selection for type,val pairs
const locals now detect if the value ends up being comptime known. In
such case, it replaces the runtime AIR instructions with a decl_ref
const.
In the backends, some more sophisticated logic for marking decls as
alive was needed to prevent Decls incorrectly being garbage collected
that were indirectly referenced in such manner.
Add a variant of the `validate_struct_init` ZIR instruction:
`validate_struct_init_comptime` which is the same thing except it
indicates a comptime scope.
Sema code for this instruction now handles default struct field
values and detects when the struct initialization resulted in a
comptime value, replacing the already-emitted AIR instructions
to store each individual field with a single `store` instruction
with a comptime struct value as the operand.
In the case of a comptime scope, there is a simpler path that only
evals the implicit store instructions for default field values, avoiding
the mechanism for detecting comptime values.
This regressed one test case for the wasm backend, but it's just hitting
a different prong of `emitConstant` which currently has "TODO" in there,
so I think it's fine.
