Move the cast_float_to_int fallback code to GCC
Now that we require at least LLVM 13, that codegen backend is always
using its intrinsic `fptosi.sat` and `fptoui.sat` conversions, so it
doesn't need the manual implementation. However, the GCC backend still
needs it, so we can move all of that code down there.
interpret: make read-pointer-as-bytes a CTFE-only error with extra information
Next step in the reaction to https://github.com/rust-lang/rust/issues/99923. Also teaches Miri to implicitly strip provenance in more situations when transmuting pointers to integers, which fixes https://github.com/rust-lang/miri/issues/2456.
Pointer-to-int transmutation during CTFE now produces a message like this:
```
= help: this code performed an operation that depends on the underlying bytes representing a pointer
= help: the absolute address of a pointer is not known at compile-time, so such operations are not supported
```
r? ``@oli-obk``
Add pointer masking convenience functions
This PR adds the following public API:
```rust
impl<T: ?Sized> *const T {
fn mask(self, mask: usize) -> *const T;
}
impl<T: ?Sized> *mut T {
fn mask(self, mask: usize) -> *const T;
}
// mod intrinsics
fn mask<T>(ptr: *const T, mask: usize) -> *const T
```
This is equivalent to `ptr.map_addr(|a| a & mask)` but also uses a cool llvm intrinsic.
Proposed in https://github.com/rust-lang/rust/pull/95643#issuecomment-1121562352
cc `@Gankra` `@scottmcm` `@RalfJung`
r? rust-lang/libs-api
Implements the following simd reduction intrinsics:
- simd_reduce_add_ordered
- simd_reduce_mul_ordered
- simd_reduce_min_nanless
- simd_reduce_max_nanless
- simd_reduce_xor
- simd_reduce_any
- simd_reduce_all
Also fixes the ordering of simd_reduce_min and simd_reduce_max,
which were tested to be flipped.
Both simd_reduce_min_nanless and simd_reduce_max_nanless are identical
to their non-nanless variants for the time being. An attempt was made
at a more optimal codegen solution based on vector_reduce_op. However,
this approach ran into masking issues for floating-point vector types,
which appears to be broken for the same reason that comparison
operations such as simd_lt are broken for floating-point vector types.
More investigation is required, however, to determine a root cause and
appropriate fix.
This should be enough to pass the generic-reduction-pass.rs ui tests
with the 'master' feature enabled.
Signed-off-by: Andy Sadler <andrewsadler122@gmail.com>
Currently they try to be very precise. But they are wrong, i.e. they
don't match what's happening in the loop below. This code isn't hot
enough for it to matter that much.
Because `PassMode::Cast` is by far the largest variant, but is
relatively rare.
This requires making `PassMode` not impl `Copy`, and `Clone` is no
longer necessary. This causes lots of sigil adjusting, but nothing very
notable.
Now that we require at least LLVM 13, that codegen backend is always
using its intrinsic `fptosi.sat` and `fptoui.sat` conversions, so it
doesn't need the manual implementation. However, the GCC backend still
needs it, so we can move all of that code down there.
