This adds support for the simd variants of the pointer provenance
intrinsics, which are `simd_cast_ptr`, `simd_expose_addr`, and
`simd_from_exposed_addr`.
The preconditions for each intrinsic are adapted from rustc_codegen_llvm
to preserve compatibility. Each of these intrinsics are implemented as
calling the non-simd variant of each intrinsic on each lane.
This is enough to enable the UI test `ui/simd/intrinsic/ptr-cast.rs` to
pass.
Signed-off-by: Andy Sadler <andrewsadler122@gmail.com>
a0b4d735e3