; RUN: llc < %s -march=arm64 ; This test case tests an infinite loop bug in DAG combiner. ; It just tries to do the following replacing endlessly: ; (1) Replacing.3 0x2c509f0: v4i32 = any_extend 0x2c4cd08 [ORD=4] ; With: 0x2c4d128: v4i32 = sign_extend 0x2c4cd08 [ORD=4] ; ; (2) Replacing.2 0x2c4d128: v4i32 = sign_extend 0x2c4cd08 [ORD=4] ; With: 0x2c509f0: v4i32 = any_extend 0x2c4cd08 [ORD=4] ; As we think the (2) optimization from SIGN_EXTEND to ANY_EXTEND is ; an optimization to replace unused bits with undefined bits, we remove ; the (1) optimization (It doesn't make sense to replace undefined bits ; with signed bits). define <4 x i32> @infiniteLoop(<4 x i32> %in0, <4 x i16> %in1) { entry: %cmp.i = icmp sge <4 x i16> %in1, %sext.i = sext <4 x i1> %cmp.i to <4 x i32> %mul.i = mul <4 x i32> %in0, %sext.i %sext = shl <4 x i32> %mul.i, %vmovl.i.i = ashr <4 x i32> %sext, ret <4 x i32> %vmovl.i.i }