I was curious to poke around at wasm64-unknown-unknown support for Rust recently and I ran into a crash with SIMD test cases which I was able to reduce to:



target triple = "wasm64-unknown-unknown"

define void @foo(<4 x i32> * %a, i32* %b) #0 {
  store <4 x i32> zeroinitializer, <4 x i32>* %a, align 16
  %1 = load <4 x i32>, <4 x i32>* %a, align 16
  %2 = extractelement <4 x i32> %1, i32 0
  store i32 %2, i32* %b, align 4
  ret void
}

attributes #0 = { "target-features"="+simd128" }




which crashes with:

$ llc -filetype=obj -O2 -o foo.o ./bugpoint-reduced-simplified.ll
LLVM ERROR: Cannot select: t11: i32 = extract_vector_elt t6, Constant:i64<0>
  t6: v4i32 = BUILD_VECTOR Constant:i32<0>, Constant:i32<0>, Constant:i32<0>, Constant:i32<0>
    t5: i32 = Constant<0>
    t5: i32 = Constant<0>
    t5: i32 = Constant<0>
    t5: i32 = Constant<0>
  t7: i64 = Constant<0>
In function: foo
PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
Stack dump:
0.      Program arguments: ../rust/build/aarch64-unknown-linux-gnu/llvm/bin/llc -filetype=obj -O2 -o foo.o ./bugpoint-reduced-simplified.ll
1.      Running pass 'Function Pass Manager' on module './bugpoint-reduced-simplified.ll'.
2.      Running pass 'WebAssembly Instruction Selection' on function '@foo'