Runtime `@shuffle` has two cases which backends generally want to handle
differently for efficiency:
* One runtime vector operand; some result elements may be comptime-known
* Two runtime vector operands; some result elements may be undefined
The latter case happens if both vectors given to `@shuffle` are
runtime-known and they are both used (i.e. the mask refers to them).
Otherwise, if the result is not entirely comptime-known, we are in the
former case. `Sema` now diffentiates these two cases in the AIR so that
backends can easily handle them however they want to. Note that this
*doesn't* really involve Sema doing any more work than it would
otherwise need to, so there's not really a negative here!
Most existing backends have their lowerings for `@shuffle` migrated in
this commit. The LLVM backend uses new lowerings suggested by Jacob as
ones which it will handle effectively. The x86_64 backend has not yet
been migrated; for now there's a panic in there. Jacob will implement
that before this is merged anywhere.
This adds 4 `Legalize.Feature`s:
* `expand_intcast_safe`
* `expand_add_safe`
* `expand_sub_safe`
* `expand_mul_safe`
These do pretty much what they say on the tin. This logic was previously
in Sema, used when `Zcu.Feature.safety_checked_instructions` was not
supported by the backend. That `Zcu.Feature` has been removed in favour
of this legalization.
We don't seem to be getting non-deterministic hangs since 4f3b59f, and e28b402
cut the run times significantly on top of that. Runs now seem to take around 1-2
hours, so the default timeout should be plenty.
This defines a WinMain() function that can be potentially problematic when it
isn't wanted. If we add back support for this library in the future, it should
be built separately from mingw32.lib and on demand.
These are almost entirely identical, with these exceptions:
* lib/libc/include/csky-linux-{gnueabi,gnueabihf}
* gnu/{lib-names,stubs}.h will need manual patching for float ABI.
* lib/libc/include/{powerpc-linux-{gnueabi,gnueabihf},{powerpc64,powerpc64le}-linux-gnu}
* bits/long-double.h will need manual patching for long double ABI.
std tests are temporarily disabled for arm-freebsd-eabihf due to #23949.
I omitted x86-freebsd-none and powerpc-freebsd-none because these will be
dropped in FreeBSD 15.0 anyway, so there's no point in us spending resources on
those now.
There's not really any point in targeting *-windows-(gnu,msvc) when not linking
libc, so add entries for *-windows-(gnu,msvc) that actually link libc, and
change the old non-libc entries to *-windows-none.
Also add missing aarch64-windows-(none,msvc) and thumb-windows-(none,msvc)
entries. thumb-windows-gnu is disabled for now due to #24016.
Each target can opt into different sets of legalize features.
By performing these transformations before liveness, instructions
that become unreferenced will have up-to-date liveness information.
This is equivalent to `array_elem_val`, and doing that conversion in
Sema (seems reasonable since it's just a simple branch) is much easier
for the self-hosted x86_64 backend then actually handling this case.
