This change implements the compiler runtime for ARM v8.1 ISE atomics and
gets rid of the mandatory -mno-outline-atomics flag. It can dramatically
speed things up, on newer ARM CPUs, as indicated by the changed lines in
test/libc/thread/footek_test.c. In llamafile dispatching on hwcap atomic
also shaved microseconds off synchronization barriers.
So far I haven't found any way to run native Arm64 code on Windows Arm64
without using MSVC. When I build a PE binary from scratch that should be
a valid Windows Arm64 program, the OS refuses to run it. Possibly due to
requiring additional content like XML manifests or relocation or control
flow integrity data that isn't normally required on x64. I've also tried
using VirtualAlloc2() to JIT an Arm64 native function, but VirtualAlloc2
always fails with invalid parameter. I tried using MSVC to create an ARM
DLL that my x64 emulated program can link at runtime, to pass a function
pointer with ARM code, but LoadLibrary() rejects ARM DLLs as invalid exe
The only option left, is likely to write a new program like ape/ape-m1.c
which can be compiled by MSVC to load and run an AARCH64 ELF executable.
The emulated x64 binary would detect emulation using IsWow64Process2 and
then drop the loader executable in a temporary folder, and re-launch the
original executable, using the Arm64 segments of the cosmocc fat binary.
The WIN32 CreateProcess() function does not require an .exe or .com
suffix in order to spawn an executable. Now that we have Cosmo bash
we're no longer so dependent on the cmd.exe prompt.
This change upgrades to GCC 12.3 and GNU binutils 2.42. The GNU linker
appears to have changed things so that only a single de-duplicated str
table is present in the binary, and it gets placed wherever the linker
wants, regardless of what the linker script says. To cope with that we
need to stop using .ident to embed licenses. As such, this change does
significant work to revamp how third party licenses are defined in the
codebase, using `.section .notice,"aR",@progbits`.
This new GCC 12.3 toolchain has support for GNU indirect functions. It
lets us support __target_clones__ for the first time. This is used for
optimizing the performance of libc string functions such as strlen and
friends so far on x86, by ensuring AVX systems favor a second codepath
that uses VEX encoding. It shaves some latency off certain operations.
It's a useful feature to have for scientific computing for the reasons
explained by the test/libcxx/openmp_test.cc example which compiles for
fifteen different microarchitectures. Thanks to the upgrades, it's now
also possible to use newer instruction sets, such as AVX512FP16, VNNI.
Cosmo now uses the %gs register on x86 by default for TLS. Doing it is
helpful for any program that links `cosmo_dlopen()`. Such programs had
to recompile their binaries at startup to change the TLS instructions.
That's not great, since it means every page in the executable needs to
be faulted. The work of rewriting TLS-related x86 opcodes, is moved to
fixupobj.com instead. This is great news for MacOS x86 users, since we
previously needed to morph the binary every time for that platform but
now that's no longer necessary. The only platforms where we need fixup
of TLS x86 opcodes at runtime are now Windows, OpenBSD, and NetBSD. On
Windows we morph TLS to point deeper into the TIB, based on a TlsAlloc
assignment, and on OpenBSD/NetBSD we morph %gs back into %fs since the
kernels do not allow us to specify a value for the %gs register.
OpenBSD users are now required to use APE Loader to run Cosmo binaries
and assimilation is no longer possible. OpenBSD kernel needs to change
to allow programs to specify a value for the %gs register, or it needs
to stop marking executable pages loaded by the kernel as mimmutable().
This release fixes __constructor__, .ctor, .init_array, and lastly the
.preinit_array so they behave the exact same way as glibc.
We no longer use hex constants to define math.h symbols like M_PI.
Now that our socket system call polyfills are good enough to support
Musl's DNS library we should be using that rather than the barebones
domain name system implementation we rolled on our own. There's many
benefits to making this change. So many, that I myself wouldn't feel
qualified to enumerate them all. The Musl DNS code had to be changed
in order to support Windows of course, which looks very solid so far
Somehow or another, I previously had missed `BUILD.mk` files.
In the process I found a few straggler cases where the modeline was
different from the file, including one very involved manual fix where a
file had been treated like it was ts=2 and ts=8 on separate occasions.
The commit history in the PR shows the gory details; the BUILD.mk was
automated, everything else was mostly manual.
