I was able to trigger an issue extending f32::MAX or f32::MIN to a f64.
Issue was not triggered by `testcrate` mainly because f32::MAX/MIN are
not in the list of special values to generate.
This PR fix the issue and improve `testcrate` adding MAX/MIN/MIN_POSITIVE
in the list of special values.
Add `extend` module to implement conversion from a narrower to a wider
floating-point type.
This implementation is only intended to support *widening* operations.
Module to convert a *narrower* floating-point will be added in the future.
All tests are moved to a separate crate in this repository to enable features by
default. Additionally the test generation is moved to a seprate build script and
simplified to reduce the amount of boilerplate needed per test.
Overall this should still be testing everything, just in a different location!
Here using `"C"` the compiler will use `"aapcs"` or `"aapcs-vfp"`
depending on target configuration.
Of course this translates in a call to `__aeabi_fdiv` / `__aeabi_fmul`
on non-HF targets.
On `eabi` targets with +vfpv2/vfpv3 LLVM generate:
vmov s0, r1
vmov s2, r0
vdiv.f32 s0, s2, s0
vmov r0, s0
bx lr
On `eabihf` targets with +vfpv3-d16/d32/f32 +fp-only-sp LLVM generate:
vdiv.f32 s0, s0, s1
bx lr
That's exactly what We need for [div/mul][s/d]f3vfp.S
* I believe `__gtdf2` erroneously used `f32` instead of `f64`
* Most of these needed `#[arm_aeabi_alias]` to ensure they're correctly called
through the alias
* Some existing aliases were corrected with the right names
First of all aeabi_cdcmp and aeabi_cfcmp are never called LLVM.
Second are little-endian only, so build fail on big-endian targets.
Temporally workaround: exclude these files for big-endian targets.
Note that this changes semantics:
pub extern "C" fn __eqsf2(a: f32, b: f32) -> bool {
cmp(a, b).to_le_abi() != 0
}
is not the same as
pub extern "C" fn __eqsf2(a: f32, b: f32) -> i32 {
cmp(a, b).to_le_abi()
}
However, compiler-rt does the latter, so this is actually
an improvement.
E.g. take a look at the assembly output for:
pub fn comparesf2(a: f32, b: f32) -> bool { a > b }
pub fn comparedf2(a: f64, b: f64) -> bool { a > b }
which will include calls to __gtsf2 and __gtdf2.
Use the "volatile" option and the "memory" clobber on inline asm that does
things like return directly, to reduce the chances of compilers rearranging
the code.
This commit prepares the build script for a wasm32 target that doesn't use
Emcripten, notably forcing the `mem` feature to get activated and forcibly
ignoring the `c` feature, even if activated, for the wasm32 target.
Instead use the Cargo runner feature. The binfmt_misc approach requires running a privileged
container for setup. Not all docker setups support privileged containers so the test suite should be
more accessible with this change as no privileged container is needed.
