1 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-sse4.1 | FileCheck %s --check-prefix=NO_SSE_41 2 ; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse4.1 | 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 ; NO_SSE_41-LABEL: trunc_sext: 13 ; NO_SSE_41: # BB#0: 14 ; NO_SSE_41-NEXT: movq {{.*#+}} xmm0 = mem[0],zero 15 ; NO_SSE_41-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3] 16 ; NO_SSE_41-NEXT: pslld $24, %xmm0 17 ; NO_SSE_41-NEXT: psrad $24, %xmm0 18 ; NO_SSE_41-NEXT: retq 19 ; 20 ; SSE_41-LABEL: trunc_sext: 21 ; SSE_41: # BB#0: 22 ; SSE_41-NEXT: pmovzxwd {{.*#+}} xmm0 = mem[0],zero,mem[1],zero,mem[2],zero,mem[3],zero 23 ; SSE_41-NEXT: pslld $24, %xmm0 24 ; SSE_41-NEXT: psrad $24, %xmm0 25 ; SSE_41-NEXT: retq 26 %load = load <4 x i16>, <4 x i16>* %in 27 %trunc = trunc <4 x i16> %load to <4 x i8> 28 %sext = sext <4 x i8> %trunc to <4 x i32> 29 ret <4 x i32> %sext 30 } 31 32
