Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
The signature is `getOrCreateSubrange(int64_t Lo, int64_t Count)`, so this updates the bindings to match.
This fixes a crash in `lowerDebugTypeImpl` when analyzing slices that have a length of 2^32 or
larger (up to `2^64 >> 3`, which still crashes, because above that the array size in bits overflows u64).
Since the Zig language documentation claims support for `.Min` and
`.Max` in `@atomicRmw` with floats, allow in Sema and implement for both
the llvm and C backends.
This commit enables producing 64-bit DWARF format for Zig executables
that are produced through the LLVM backend. This is achieved by exposing
both command-line flags and CompileStep flags. The production of the
64-bit format only affects binaries that use the DWARF format and it is
disabled on MacOS due to it being problematic. This commit, despite
generating the interface for the Zig user to be able to tell the compile
which format is wanted, is just implemented for the LLVM backend, so
clang and the self-hosted backends will need this to be implemented in a
future commit.
This is an effort to work around #7962, since the emission of the 64-bit
format automatically produces 64-bit relocations. Further investigation
will be needed to make DWARF 32-bit format to emit bigger relocations
when needed and not make the linker angry.
When using llvm opaque pointers, typed pointers and pointer bitcasts are
no longer needed. This also avoids needing packed struct layouts that
are nested inside pointers, letting us avoid computing struct layouts
in Sema that could cause unnecessary dependency loops.
This commit changes the way Zig is intended to deal with variable
declaration for exotic targets. Where previously the idea was to
enfore local/global variables to be placed into their respective
address spaces, depending on the target, this is now fixed to the
generic address space.
To facilitate this for targets where local variables _must_ be
generated into a specific address space (ex. amdgcn where locals
must be generated into the private address space), the variable
allocations (alloca) are generated into the right address space
and then addrspace-casted back to the generic address space. While this
could be less efficient in theory, LLVM will hopefull deal with figuring
out the actual correct address space for a pointer for us. HIP seems to
do the same thing in this regard.
Global variables are handled in a similar way.
These const qualifiers on pointers to opaque types do not serve any
purpose. If anything they are misleading since the underlying pointers
very likely point to objects that are in fact mutated.
This commit does not change any behavior.
This bug manifested as a segfault in stage1 when calling this function.
The C++ code looks like this:
```c++
entry->llvm_di_type = ZigLLVMCreateDebugForwardDeclType(g->dbuilder,
ZigLLVMTag_DW_structure_type(), full_name,
import ? ZigLLVMFileToScope(import->data.structure.root_struct->di_file) : nullptr,
import ? import->data.structure.root_struct->di_file : nullptr,
line);
```
There is actually no problem here - what happened is that because
cross-language LTO was enabled between zig and c++ code, and because
Zig annotated the file parameter (3rd line) as being non-null, the C++
code assumed that parameter could not be null, and eagerly dereferenced
`import->...`, causing a segfault, since it was null.
I verified that this commit fixed the problem and I also verified this
hypothesis by disabling LTO and noticing that it indeed avoided the
problem.
As part of the Opaque Pointers upgrade documentation, LLVM says that the
function LLVMGetGEPSourceElementType() can be used to obtain element
type information in lieu of LLVMGetElementType(), however, this function
actually returns the struct type, not the field type. The GEP
instruction does store the information we need, however, this is not
exposed in the C API. It seems like they accidentally exposed the wrong
field, because one would never need the struct type since one must
already pass it directly to the GEP instruction, so one will always have
it handy, whereas one will usually not have the field type handy.
Previously, the Zig ABI size and LLVM ABI size of these types disagreed
sometimes. This code also corrects the logging messages to not trigger
LLVM assertions.
