Function core::arch::wasm32::i64x2_extend_low_i32x4

pub fn i64x2_extend_low_i32x4(a: v128) -> v128

This is supported on (non-crate feature miri-test-libstd or test or doctest) and WebAssembly and target feature simd128 only.

Converts low half of the smaller lane vector to a larger lane vector, sign extended.