Cranelift: Wrong result for urem.i8 on RISC-V

[afonso360]

👋 Hey,

Fuzzgen found this today.

.clif Test Case

test interpret
test run
target riscv64gc

function %a() -> i8  {
block0:
    v3 = iconst.i8 208
    v11 = urem v3, v3  ; v3 = 208, v3 = 208
    return v11
}

; run: %a() == 0

Steps to Reproduce

• clif-util test ./the-above.clif

Expected Results

The test to pass.

Actual Results

afonso@DESKTOP-1AHKMV2:~/git/wasmtime/cranelift$ cargo run --target=riscv64gc-unknown-linux-gnu -- test ./lmao.clif 
    Finished dev [unoptimized + debuginfo] target(s) in 0.15s
     Running `/home/afonso/git/qemu/build/qemu-riscv64 -L /usr/riscv64-linux-gnu -E LD_LIBRARY_PATH=/usr/riscv64-linux-gnu/lib -E WASMTIME_TEST_NO_HOG_MEMORY=1 -cpu rv64,v=true,vlen=128,vext_spec=v1.0,zba=true,zbb=true,zbs=true,zbc=true,zbkb=true,zcb=true,x-zicond=true /home/afonso/git/wasmtime/target/riscv64gc-unknown-linux-gnu/debug/clif-util test ./lmao.clif`
 ERROR cranelift_filetests::concurrent > FAIL: run
FAIL ./lmao.clif: run

Caused by:
    Failed test: run: %a() == 0, actual: -48
1 tests
Error: 1 failure

Versions and Environment

Cranelift version or commit: main

Operating system: Linux

Architecture: RISC-V 64