1; RUN: llc < %s -mtriple=aarch64--linux-gnu | FileCheck %s 2 3; PR23065: SCALAR_TO_VECTOR implies the top elements 1 to N-1 of the N-element vector are undefined. 4 5define <4 x i16> @foo1(<2 x i32> %a) { 6; CHECK-LABEL: foo1: 7; CHECK: movi v0.2d, #0000000000000000 8; CHECK-NEXT: ret 9 10 %1 = shufflevector <2 x i32> <i32 58712, i32 undef>, <2 x i32> %a, <2 x i32> <i32 0, i32 2> 11; Can't optimize the following bitcast to scalar_to_vector. 12 %2 = bitcast <2 x i32> %1 to <4 x i16> 13 %3 = shufflevector <4 x i16> %2, <4 x i16> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef> 14 ret <4 x i16> %3 15} 16 17define <4 x i16> @foo2(<2 x i32> %a) { 18; CHECK-LABEL: foo2: 19; CHECK: movi v0.2d, #0000000000000000 20; CHECK-NEXT: ret 21 22 %1 = shufflevector <2 x i32> <i32 712, i32 undef>, <2 x i32> %a, <2 x i32> <i32 0, i32 2> 23; Can't optimize the following bitcast to scalar_to_vector. 24 %2 = bitcast <2 x i32> %1 to <4 x i16> 25 %3 = shufflevector <4 x i16> %2, <4 x i16> undef, <4 x i32> <i32 1, i32 undef, i32 undef, i32 undef> 26 ret <4 x i16> %3 27} 28