LLVM ERROR: Cannot select: t8: v4f32 = froundeven nnan ninf nsz contract afn reassoc t7

[vksnk]

This seems to be happening with LLVM18 on our buildbots (https://buildbot.halide-lang.org/master/#/builders/128/builds/156) (we also started to see this internally in Google tests).

LLVM ERROR: Cannot select: t8: v4f32 = froundeven nnan ninf nsz contract afn reassoc t7 t7: v4f32 = concat_vectors t46, undef:v2f32 t46: v2f32,i32,ch = ARMISD::VLD1_UPD<(load (s64) from %ir.lsr.iv, align 4, !tbaa !45)> t0, t2, Constant:i32<8>, Constant:i32<1> t2: i32,ch = CopyFromReg t0, Register:i32 %35 t1: i32 = Register %35 t14: i32 = Constant<8> t43: i32 = Constant<1> t6: v2f32 = undef In function: f3