2d25db047f
Cranelift only has one instruction SIMD which depends on SSE4.2 so this commit adds a lowering rule for `pcmpgtq` which doesn't use SSE4.2 and enables lowering the baseline requirement for SIMD support from SSE4.2 to SSE4.1. The `has_sse42` setting is no longer enabled by default for Cranelift. Additionally `enable_simd` no longer requires `has_sse42` on x64. Finally the fuzz-generator for Wasmtime codegen settings now enables flipping the `has_sse42` setting instead of unconditionally setting it to `true`. The specific lowering for `pcmpgtq` is copied from LLVM's lowering of this instruction.
filetests
Filetests is a crate that contains multiple test suites for testing
various parts of cranelift. Each folder under cranelift/filetests/filetests is a different
test suite that tests different parts.
Adding a runtest
One of the available testsuites is the "runtest" testsuite. Its goal is to compile some piece of clif code, run it and ensure that what comes out is what we expect.
To build a run test you can add the following to a file:
test interpret
test run
target x86_64
target aarch64
target s390x
function %band_f32(f32, f32) -> f32 {
block0(v0: f32, v1: f32):
v2 = band v0, v1
return v2
}
; run: %band_f32(0x0.5, 0x1.0) == 0x1.5
Since this is a run test for band we can put it in: runtests/band.clif.
Once we have the file in the test suite we can run it by invoking: cargo run -- test filetests/filetests/runtests/band.clif from the cranelift directory.
The first lines tell clif-util what kind of tests we want to run on this file.
test interpret invokes the interpreter and checks if the conditions in the ; run comments pass. test run does the same, but compiles the file and runs it as a native binary.
For more information about testing see testing.md.