* Use a no-asm feature instead of an asm feature
This works better as core/alloc/std have trouble supporting default
featues in this crate.
Signed-off-by: Joe Richey <joerichey@google.com>
* Have no-asm disable arm assembly intrinsics
Signed-off-by: Joe Richey <joerichey@google.com>
* Reorganize mem functions
This reduces the amount of platform-specific code
Signed-off-by: Joe Richey <joerichey@google.com>
* Use ERMSB implementations if the feature is set
Signed-off-by: Joe Richey <joerichey@google.com>
* Add non-aligned benchmarks
Signed-off-by: Joe Richey <joerichey@google.com>
* mem: Move mem* functions to separate directory
Signed-off-by: Joe Richey <joerichey@google.com>
* memcpy: Create separate memcpy.rs file
Signed-off-by: Joe Richey <joerichey@google.com>
* benches: Add benchmarks for mem* functions
This allows comparing the "normal" implementations to the
implementations provided by this crate.
Signed-off-by: Joe Richey <joerichey@google.com>
* mem: Add REP MOVSB/STOSB implementations
The assembly generated seems correct:
https://rust.godbolt.org/z/GGnec8
Signed-off-by: Joe Richey <joerichey@google.com>
* mem: Add documentations for REP string insturctions
Signed-off-by: Joe Richey <joerichey@google.com>
* Use quad-word rep string instructions
Signed-off-by: Joe Richey <joerichey@google.com>
* Prevent panic when compiled in debug mode
Signed-off-by: Joe Richey <joerichey@google.com>
* Add tests for mem* functions
Signed-off-by: Joe Richey <joerichey@google.com>
* Add build/test with the "asm" feature
Signed-off-by: Joe Richey <joerichey@google.com>
* Add byte length to Bencher
Signed-off-by: Joe Richey <joerichey@google.com>
1. In UEFI x86 arch, probestack need triple underscore.
2. In UEFI, probestack function do things like _chkstk(in MSVC).
MSVC x32's _chkstk and cygwin/mingw's _alloca adjust %esp themselves
MSVC x64's __chkstk and cygwin/mingw's ___chkstk_ms do not adjust
%rsp themselves.
But current probestack doesn't adjust esp. And LLVM doesn't generate
sub %eax, %esp after probestack. So we adjust esp in probestack like
MSVC x32's _chkstk.
* add 32 bit shift instructions to src/int/shift.rs
__ashlsi3
__ashrsi3
__lshrsi3
* add int_impl! for 16 bit numbers and large_int! for i32 and u32
* add tests in testcrate/build.rs
https://github.com/rust-lang/rust/pull/72700 caused the existing
`allow(improper_ctypes)` guard to stop working, we now need
`allow(improper_ctypes_definitions)` instead.
We keep the old one to avoid any issues with older nightlies.
Signed-off-by: Joe Richey <joerichey@google.com>
* Expand wasm32 testing on CI
Run the full `run.sh` test script to get full assertions, including that
nothing in the wasm compiler-builtins is panicking. Unfortunately it's
currently panicking, so this is good to weed out!
* Update libm
* Allow FFI-unsafe warnings for u128/i128
Handle new warnings on nightly, and we shouldn't need to worry about
these with compiler-builtins since this is tied to a particular compiler.
* Clean up crate attributes
* No need for stability marker
* Rustdoc docs not used for this crate
* Remove old build-system related cruft from rustc itself.
* Run `cargo fmt`
As of LLVM 9.0, certain calls to memcmp may be converted to bcmp, which I guess
could save a single subtraction on some architectures. [1]
bcmp is just like memcmp except instead of returning the difference between the
two differing bytes, it returns non-zero instead. As such, memcmp is a valid
implementation of bcmp.
If we care about size, bcmp should just call memcmp.
If we care about speed, we can change bcmp to look like this instead:
```rust
pub unsafe extern "C" fn bcmp(s1: *const u8, s2: *const u8, n: usize) -> i32 {
let mut i = 0;
while i < n {
let a = *s1.offset(i as isize);
let b = *s2.offset(i as isize);
if a != b {
return 1;
}
i += 1;
}
0
}
```
In this PR I do not address any changes which may or may not be needed for arm
aebi as I lack proper test hardware.
[1]: https://releases.llvm.org/9.0.0/docs/ReleaseNotes.html#noteworthy-optimizations
This turns the following backtrace,
```
>> bt
#0 0x0000555555576f73 in __rust_probestack () at /cargo/registry/src/github.com-1ecc6299db9ec823/compiler_builtins-0.1.14/src/probestack.rs:55
Backtrace stopped: Cannot access memory at address 0x7fffff7fedf0
```
To this:
```
>>> bt
#0 0x0000555555574e47 in __rust_probestack ()
#1 0x00005555555595ba in test::main ()
#2 0x00005555555594f3 in std::rt::lang_start::{{closure}} ()
#3 0x0000555555561ae3 in std::panicking::try::do_call ()
#4 0x000055555556595a in __rust_maybe_catch_panic ()
#5 0x000055555555af9b in std::rt::lang_start_internal ()
#6 0x00005555555594d5 in std::rt::lang_start ()
#7 0x000055555555977b in main ()
```
