fallback: legalize: G_LSHR <8 x s32>

Snippet:

; Function Attrs: nounwind
define <8 x i16> @umulh_v8i16(<8 x i16> %x, <8 x i16> %y) #0 {
  %r = call <8 x i16> @llvm.umulh.v8i16(<8 x i16> %x, <8 x i16> %y)
  ret <8 x i16> %r
}

; Function Attrs: nocallback nocreateundeforpoison nofree nosync nounwind speculatable willreturn memory(none)
declare <8 x i16> @llvm.umulh.v8i16(<8 x i16>, <8 x i16>) #1

attributes #0 = { nounwind }
attributes #1 = { nocallback nocreateundeforpoison nofree nosync nounwind speculatable willreturn memory(none) }

Reproduce:

llc -mtriple=riscv32 -mattr=+m -global-isel -global-isel-abort=2 -pass-remarks-missed=gisel.* snippet.ll -o -
llc -mtriple=riscv32 -mattr=+m -global-isel=0 snippet.ll -o -

Local llc output:

remark: <unknown>:0:0: unable to legalize instruction: %33:_(<8 x s32>) = G_LSHR %30:_, %32:_(<8 x s32>) (in function: umulh_v8i16)
warning: Instruction selection used fallback path for umulh_v8i16

Occurrences (2):

Generated 2026-10-15 08:05 UTC.