1c3a1bda6c
* x64: Add lowerings for `punpck{h,l}wd`
Add some special cases for `shuffle` for more specialized x86
instructions.
* x64: Add `shuffle` lowerings for `pshufd`
This commit adds special-cased lowerings for the x64 `shuffle`
instruction when the `pshufd` instruction alone is necessary. This is
possible when the shuffle immediate permutes 32-bit values within one of
the vector inputs of the `shuffle` instruction, but not both.
* x64: Add shuffle lowerings for `punpck{h,l}{q,}dq`
This adds specific permutations for some x86 instructions which
specifically interleave high/low bytes for 32 and 64-bit values. This
corresponds to the preexisting specific lowerings for interleaving 8 and
16-bit values.
* x64: Add `shuffle` lowerings for `shufps`
This commit adds targeted lowerings for the `shuffle` instruction that
match the pattern that `shufps` supports. The `shufps` instruction
selects two elements from the first vector and two elements from the
second vector which means while it's not generally applicable it should
still be more useful than the catch-all lowering of `shuffle`.
* x64: Add shuffle support for `pshuf{l,h}w`
This commit adds special lowering cases for these instructions which
permute 16-bit values within a 128-bit value either within the upper or
lower half of the 128-bit value.
* x64: Specialize `shuffle` with an all-zeros immediate
Instead of loading the all-zeros immediate from a rip-relative address
at the end of the function instead generate a zero with a `pxor`
instruction and then use `pshufb` to do the broadcast.
* Review comments
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.