Before calling populateTestFunctions() we want to check
totalErrorCount() but that will read from some tables that might get
populated by the thread pool for C compilation tasks. So we wait until
all those tasks are finished before proceeding.
Frontend improvements:
* When compiling in `zig test` mode, put a task on the work queue to
analyze the main package root file. Normally, start code does
`_ = import("root");` to make Zig analyze the user's code, however in
the case of `zig test`, the root source file is the test runner.
Without this change, no tests are picked up.
* In the main pipeline, once semantic analysis is finished, if there
are no compile errors, populate the `test_functions` Decl with the
set of test functions picked up from semantic analysis.
* Value: add `array` and `slice` Tags.
LLVM backend improvements:
* Fix incremental updates of globals. Previously the
value of a global would not get replaced with a new value.
* Fix LLVM type of arrays. They were incorrectly sending
the ABI size as the element count.
* Remove the FuncGen parameter from genTypedValue. This function is for
generating global constants and there is no function available when
it is being called.
- The `ref_val` case is now commented out. I'd like to eliminate
`ref_val` as one of the possible Value Tags. Instead it should
always be done via `decl_ref`.
* Implement constant value generation for slices, arrays, and structs.
* Constant value generation for functions supports the `decl_ref` tag.
* Add AIR instruction: struct_field_val
- This is part of an effort to eliminate the AIR instruction `ref`.
- It's implemented for C backend and LLVM backend so far.
* Rename `resolvePossiblyUndefinedValue` to `resolveMaybeUndefVal` just
to save some columns on long lines.
* Sema: add `fieldVal` alongside `fieldPtr` (renamed from
`namedFieldPtr`). This is part of an effort to eliminate the AIR
instruction `ref`. The idea is to avoid unnecessary loads, stores,
stack usage, and IR instructions, by paying a DRY cost.
LLVM backend improvements:
* internal linkage vs exported linkage is implemented, along with
aliases. There is an issue with incremental updates due to missing
LLVM API for deleting aliases; see the relevant comment in this commit.
- `updateDeclExports` is hooked up to the LLVM backend now.
* Fix usage of `Type.tag() == .noreturn` rather than calling `isNoReturn()`.
* Properly mark global variables as mutable/constant.
* Fix llvm type generation of function pointers
* Fix codegen for calls of function pointers
* Implement llvm type generation of error unions and error sets.
* Implement AIR instructions: addwrap, subwrap, mul, mulwrap, div,
bit_and, bool_and, bit_or, bool_or, xor, struct_field_ptr,
struct_field_val, unwrap_errunion_err, add for floats, sub for
floats.
After this commit, `zig test` on a file with `test "example" {}`
correctly generates and executes a test binary. However the
`test_functions` slice is undefined and just happens to be going into
the .bss section, causing the length to be 0. The next step towards
`zig test` will be replacing the `test_functions` Decl Value with the
set of test function pointers, before it is sent to linker/codegen.
@select(
comptime T: type,
pred: std.meta.Vector(len, bool),
a: std.meta.Vector(len, T),
b: std.meta.Vector(len, T)
) std.meta.Vector(len, T)
Constructs a vector from a & b, based on the values in the predicate vector. For indices where the predicate value is true, the corresponding
element from the a vector is selected, and otherwise from b.
* properly set global variables to const if they are not a global
variable.
* implement global variable initializations.
* initial implementation of llvmType() for structs and functions.
* implement genTypedValue for variable tags
* implement more AIR instructions: varptr, slice_ptr, slice_len,
slice_elem_val, ptr_slice_elem_val, unwrap_errunion_payload,
unwrap_errunion_payload_ptr, unwrap_errunion_err,
unwrap_errunion_err_ptr.
These AIR instructions are the next blockers for `zig test` to work for
this backend.
After this commit, the "hello world" x86_64 test case passes for the
LLVM backend as well.
This is an initial version, todo:
- Also make this work for u64 values, as the table must be indexed by u32.
- Add support for signed integers.
- Add support for enums.
* There is now a main_pkg in addition to root_pkg. They are usually the
same. When using `zig test`, main_pkg is the user's source file and
root_pkg has the test runner.
* scanDecl no longer looks for test decls outside the package being
tested. honoring `--test-filter` is still TODO.
* test runner main function has a void return value rather than
`anyerror!void`
* Sema is improved to generate better AIR for for loops on slices.
* Sema: fix incorrect capacity calculation in zirBoolBr
* Sema: add compile errors for trying to use slice fields as an lvalue.
* Sema: fix type coercion for error unions
* Sema: fix analyzeVarRef generating garbage AIR
* C codegen: fix renderValue for error unions with 0 bit payload
* C codegen: implement function pointer calls
* CLI: fix usage text
Adds 4 new AIR instructions:
* slice_len, slice_ptr: to get the ptr and len fields of a slice.
* slice_elem_val, ptr_slice_elem_val: to get the element value of
a slice, and a pointer to a slice.
AstGen gains a new functionality:
* One of the unused flags of struct decls is now used to indicate
structs that are known to have non-zero size based on the AST alone.
The include_compiler_rt stored in the bin file options means that we need
compiler-rt symbols *somehow*. However, in the context of using the stage1 backend
we need to tell stage1 to include compiler-rt only if stage1 is the place that
needs to provide those symbols. Otherwise the stage2 infrastructure will take care
of it in the linker, by putting compiler_rt.o into a static archive, or linking
compiler_rt.a against an executable. In other words we only want to set this flag
for stage1 if we are using build-obj.
When using `build-exe` or `build-lib -dynamic`, `-fcompiler-rt` means building
compiler-rt into a static library and then linking it into the executable.
When using `build-lib`, `-fcompiler-rt` means building compiler-rt into an
object file and then adding it into the static archive.
Before this commit, when using `build-obj`, zig would build compiler-rt
into an object file, and then on ELF, use `lld -r` to merge it into the
main object file. Other linker backends of LLD do not support `-r` to
merge objects, so this failed with error messages for those targets.
Now, `-fcompiler-rt` when used with `build-obj` acts as if the user puts
`_ = @import("compiler_rt");` inside their root source file. The symbols
of compiler-rt go into the same compilation unit as the root source file.
This is hooked up for stage1 only for now. Once stage2 is capable of
building compiler-rt, it should be hooked up there as well.
* Added doc comments for `std.Target.ObjectFormat` enum
* `std.Target.oFileExt` is removed because it is incorrect for Plan-9
targets. Instead, use `std.Target.ObjectFormat.fileExt` and pass a
CPU architecture.
* Added `Compilation.Directory.joinZ` for when a null byte is desired.
* Improvements to `Compilation.create` logic for computing `use_llvm`
and reporting errors in contradictory flags. `-femit-llvm-ir` and
`-femit-llvm-bc` will now imply `-fLLVM`.
* Fix compilation when passing `.bc` files on the command line.
* Improvements to the stage2 LLVM backend:
- cleaned up error messages and error reporting. Properly bubble up
some errors rather than dumping to stderr; others turn into panics.
- properly call ZigLLVMCreateTargetMachine and
ZigLLVMTargetMachineEmitToFile and implement calculation of the
respective parameters (cpu features, code model, abi name, lto,
tsan, etc).
- LLVM module verification only runs in debug builds of the compiler
- use LLVMDumpModule rather than printToString because in the case
that we incorrectly pass a null pointer to LLVM it may crash during
dumping the module and having it partially printed is helpful in
this case.
- support -femit-asm, -fno-emit-bin, -femit-llvm-ir, -femit-llvm-bc
- Support LLVM backend when used with Mach-O and WASM linkers.
then, when sorting sections within segments, clear and redo the
ordinals since we re-apply them to symbols anyway. It is vital
to have the ordinals consistent with parsing and resolving relocs
however.
Some macros (for example any macro that uses token pasting) cannot be
directly translated to Zig, but may nevertheless still admit a Zig
implementation. This provides a mechanism for matching macros against
templates and mapping them to functions implemented in c_translation.zig.
A macro matches a template if it contains the same sequence of tokens, except
that the name and parameters may be renamed. No attempt is made to
semantically analyze the macro. For example the following two macros are
considered equivalent:
```C
```
But the following two are not:
```C
```
Previously, we'd filter the nlists assuming they were correctly
ordered by type: local < extern defined < undefined within the
object's symbol table but this doesn't seem to be guaranteed,
therefore, we sort by type and address in one go, and filter
defined from undefined afterwards.
The only known use case for this is the hash-to-curve operation where the top bit is always cleared.
But the function is public, so let's make it work as one would expect in the general case.
Also fix the comment by the way.
