Unless the pointer is a pointer to a function, if the pointee type
has zero-bits, we need to return `MCValue.none` as the `Decl` has
not been lowered to memory, and therefore, any GOT reference will be
wrong.
* fix alignment issues for consts with natural ABI alignment not
matching that of the `ldr` instruction in `aarch64` - solved by
preceeding the `ldr` with an additional `add` instruction to form
the full address before dereferencing the pointer.
* redo selection of segment/section for decls and consts based on
combined type and value
Rather than ping ponging between codegen and the linker to generate the symbols/atoms
for a local constant and its relocations. We now create all neccesary objects within the linker.
This simplifies the code as we can now simply call `lowerUnnamedConst` from anywhere in codegen,
allowing us to further improve lowering constants into .rodata so we do not have to sacrifice
lowering certain types such as decl_ref's where its type is a slice.
* AstGen: remove the setBlockBodyEliding function. This is no longer
needed after 63788b2a511eb87974065a052e2436b0c6202544.
* Sema: store_to_block_ptr instruction is handled as
store_to_inferred_ptr or store, as necessary.
Instead of explicitly setting lhs to .none,
check if the lhs instruction was analyzed.
This simpler approach also handles stores from nested blocks correctly.
As of 6249a24, align() is not allowed on packed struct fields
and as such the align(4) was removed from the first field of
EdidOverrideProtocolAttributes. The endgame here is packed struct
backed by explicit integers, in this case a u32, but until that
is implemented put the align(4) on the pointer to avoid breaking
someone's UEFI code in a hard to debug way.
This reverts commit 136a43934bc08dc3aee85f1182904b97456601d3, reversing
changes made to 9dd839b7ed15d1191f3303d069cffe0473e03e83.
This broke the behavior of `zig run`.
This implements #10113 for the self-hosted compiler only. It removes the
ability to override alignment of packed struct fields, and removes the
ability to put pointers and arrays inside packed structs.
After this commit, nearly all the behavior tests pass for the stage2 llvm
backend that involve packed structs.
I didn't implement the compile errors or compile error tests yet. I'm
waiting until we have stage2 building itself and then I want to rework
the compile error test harness with inspiration from Vexu's arocc test
harness. At that point it should be a much nicer dev experience to work
on compile errors.
* goals
- zig as linker for object files generated by other compilers
- zig-specific runtime features for eventual standardisation
* changes
- missing routines are marked with `missing`
- structure inspired by libgcc docs, but improved order and wording
- rename misspelled functions
- reorder and rephrase compiler_rt.zig to reflect documentation
- potential decimal float or fixed-point arithmetic support:
* 'Decimal float library routines' ca. 120 functions
* 'Fixed-point fractional library routines' ca. 300 functions
thanks to @Vexu for multiple reviews and @scheibo for review
This instruction now just represents loading from a hard-coded adrress
after extracting the other use cases for load_memory into load_got and
load_direct.
Previously, Zig ignored -lgcc_s with a warning that this dependency is
redundant because it is satisfied by compiler-rt. However, sfackler
pointed out that it also provides exception handling functions. So if
Zig sees -lgcc_s on the linker line, it needs to fulfill this dependency
with libunwind.
I also made link_libc inferred to be on if libunwind is linked since
libunwind depends on libc.
Otherwise, we risk collisions in the global symbol table. This is
also an opportunity to generalise and rewrite the symbol table
abstraction.
Also, improve the logs for the symbol table.
Prior to this change, the routine would assume it is called first,
before any symbol was created, thus precluding an option that in the
incremental setting, we might have already pulled a suitably defined
and exported symbol that could collide and/or be replaced by the
symbol synthesised by the linker.
We now correctly implement exporting decls. This means it is possible to export
a decl with a different name than the decl that is doing the export.
This also sets the symbols with the correct flags, so when we emit a relocatable
object file, a linker can correctly resolve symbols and/or export the symbol to the host environment.
This commit also includes fixes to ensure relocations have the correct offset to how other
linkers will expect the offset, rather than what we use internally.
Other linkers accept the offset, relative to the section.
Internally we use an offset relative to the atom.
When generating a relocatable object file, we now emit a custom "reloc.CODE" and "reloc.DATA" section
which will contain the relocations for each section.
Using a new symbol location -> Atom mapping, we can now easily find the corresponding `Atom` from a symbol.
This can be used to construct the symbol table, as well as easier access to a target atom when performing
a relocation for a data symbol.
When creating a relocatable object file, we do no longer perform the following actions:
- Merge data segments
- Calculate stack size
- Relocations
We now also make the stack pointer symbol `undefined` for this use case as well as add the symbol
as an import.
When creating a relocatable object file, emit the symbol table.
We do this by iterating over all atoms, and finding the corresponding
symbols of those. This provides us all the meta information such as size, and offset as well.
This data is required for defined data symbols.
When we emit an object file, the "Names" section does not have to be emitted, as all symbol names
are already in the symbol table, so the names section is redundant.
