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      1 ; RUN: llc %s -mtriple=x86_64-unknown-unknown -mattr='-sse4.1' -o - | FileCheck %s -check-prefix=NO_SSE_41
      2 ; RUN: llc %s -mtriple=x86_64-unknown-unknown -mattr='+sse4.1' -o - | FileCheck %s -check-prefix=SSE_41
      3 
      4 ; PR20472 ( http://llvm.org/bugs/show_bug.cgi?id=20472 )
      5 ; When sexting a trunc'd vector value, we can't eliminate the zext.
      6 ; If we don't have SSE4.1, use punpck.
      7 ; If we have SSE4.1, use pmovzx because it combines the load op.
      8 ; There may be a better way to do this using pshufb + pmovsx,
      9 ; but that is beyond our current codegen capabilities.
     10 
     11 define <4 x i32> @trunc_sext(<4 x i16>* %in) {
     12   %load = load <4 x i16>, <4 x i16>* %in
     13   %trunc = trunc <4 x i16> %load to <4 x i8>
     14   %sext = sext <4 x i8> %trunc to <4 x i32>
     15   ret <4 x i32> %sext
     16 
     17 ; NO_SSE_41-LABEL: trunc_sext:
     18 ; NO_SSE_41: movq (%rdi), %xmm0
     19 ; NO_SSE_41-NEXT: punpcklwd %xmm0, %xmm0
     20 ; NO_SSE_41-NEXT: pslld $24, %xmm0
     21 ; NO_SSE_41-NEXT: psrad $24, %xmm0
     22 ; NO_SSE_41-NEXT: retq
     23 
     24 ; SSE_41-LABEL: trunc_sext:
     25 ; SSE_41: pmovzxwd (%rdi), %xmm0
     26 ; SSE_41-NEXT: pslld $24, %xmm0
     27 ; SSE_41-NEXT: psrad $24, %xmm0
     28 ; SSE_41-NEXT: retq
     29 }
     30 
     31