the current implementation only works when the struct is in a register. we use some shifting magic
to get the field into the LSB, and from there, given the type provenance, the generated code should
never reach into the bits beyond the bit size of the type and interact with the rest of the struct.
we use a code offset map in Emit.zig to pre-compute what byte offset each MIR instruction is at. this is important because they can be
of different size
- rename setRegOrMem -> setValue
- a naive method of passing arguments by register
- gather the prologue and epilogue and generate them in Emit.zig. this is cleaner because we have the final stack size in the emit step.
- define the "fa" register set, which contains the RISC-V calling convention defined function argument registers
Clang 17 passed struct{f128} parameters using rdi and rax, while Clang
18 matches GCC 13.2 behavior, passing them using xmm0.
This commit makes Zig's LLVM backend match Clang 18 and GCC 13.2. The
commit deletes a hack in x86_64/abi.zig which miscategorized f128 as
"memory" which obviously disagreed with the spec.
LLVMABIAlignmentOfType(i128) reports 16 on this target, however the C
ABI uses align(4).
Clang in LLVM 17 does this:
%struct.foo = type { i32, i128 }
Clang in LLVM 18 does this:
%struct.foo = type <{ i32, i128 }>
Clang is working around the 16-byte alignment to use align(4) for the C
ABI by making the LLVM struct packed.
release/18.x branch, commit 78b99c73ee4b96fe9ce0e294d4632326afb2db42
This adds the flag `-D_LIBCPP_HARDENING_MODE` which is determined based
on the Zig optimization mode.
This commit also fixes libunwind, libcxx, and libcxxabi to properly
report sub compilation errors.
LLVM now refuses to lower arguments and return values on x86 targets
when the total vector bit size is >= 512.
This code detects such a situation and uses byref instead of byval.
* some manual fixes to generated CPU features code. In the future it
would be nice to make the script do those automatically.
* add to various target OS switches. Some of the values I was unsure of
and added TODO panics, for example in the case of spirv CPU arch.
New OSs:
* XROS
* Serenity
* Vulkan
Removed OSs:
* Ananas
* CloudABI
* Minix
* Contiki
New CPUs:
* spirv
The removed stuff is removed from LLVM but not Zig.
This was a "fake" type used to handle C varargs parameters, much like
generic poison. In fact, it is treated identically to generic poison in
all cases other than one (the final coercion of a call argument), which
is trivially special-cased. Thus, it makes sense to remove this special
tag and instead use `generic_poison_type` in its place. This fixes
several bugs in Sema related to missing handling of this tag.
Resolves: #19781
This function accepts a WaitGroup parameter and manages the reference
counting therein. It also is infallible.
The existing `spawn` function is still handy when the job wants to
further schedule more tasks.
As of Clang 18, calling memcpy() with a misaligned pointer trips UBSAN,
even if the length is zero. This unfortunately includes any call to
`@memcpy` when source or destination are undefined and the length is
zero.
This patch makes the C backend avoid calling memcpy when the length is
zero, thereby avoiding undefined behavior.
A zig1.wasm update will be needed in the llvm18 branch to activate this
code.
