This round is dependant on
https://github.com/rust-lang/llvm-project/pull/101 landing first in
rust-lang/rust and won't pass CI until that does. That PR, however, will
also break wasm CI because it's changing how the wasm target works. My
goal here is to open this early to get it out there so that when that PR
lands in rust-lang/rust and CI breaks in stdarch then this can be merged
to make CI green again.
The changes here are mostly around the codegen for various intrinsics.
Some wasm-specific intrinsics have been removed in favor of more general
LLVM intrinsics, and other intrinsics have been removed in favor of
pattern-matching codegen.
The only new instruction supported as part of this chagne is
`v128.any_true`. This leaves only one instruction unsupported in LLVM
which is `i64x2.abs`. I think the codegen for the instruction is correct
in stdsimd, though, and LLVM just needs to update with a pattern-match
to actually emit the opcode. That'll happen in a future LLVM update.
* Uncomment some i64-related instruction assertions now that LLVM
supports the opcodes.
* Fix the codegen for `{i,u}32x4_trunc_sat_f32x4`. This was originally
introduced using `simd_cast` but that inherits LLVM's UB related to
float-to-integer casts out of bounds. Since the original inception of
these intrinsics in LLVM dedicated intrinsics for the wasm
instructions have been added, so this swithces the implementation to
using those.
* Uncomment `f64x2_convert_low_i32x4` instruction assertion and add a
test now that this is implemented in Wasmtime.
This lint is allow by default, which is why this wasn't spotted earlier.
It's denied by rust-lang/rust, so it's good to warn about it here so it
can be fixed more quickly.
While they're not very useful in single-threaded mode this makes them
more useful for building libraries because you don't have to always
recompile the standard library to get the desired effect. Additionally
it helps us enable tests on CI for these functions, since the
instructions will now validate without shared memory (thankfully!).
* Sync with the latest LLVM which has a few new intrinsic names
* Move explicit tests back to `assert_instr` since `assert_instr` now
supports specifying const-generic arguments inline.
* Enable tests where wasmtime implements the instruction as well as LLVM.
* Ensure there are tests for all functions that can be tested at this
time (those that aren't unimplemented in wasmtime).
There's still a number of `assert_instr` tests that are commented out.
These are either because they're unimplemented in wasmtime at the moment
or LLVM doesn't have an implementation for the instruction yet.
