1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
|
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-sse4.1 | FileCheck %s --check-prefix=NO_SSE_41
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse4.1 | FileCheck %s --check-prefix=SSE_41
; PR20472 ( http://llvm.org/bugs/show_bug.cgi?id=20472 )
; When sexting a trunc'd vector value, we can't eliminate the zext.
; If we don't have SSE4.1, use punpck.
; If we have SSE4.1, use pmovzx because it combines the load op.
; There may be a better way to do this using pshufb + pmovsx,
; but that is beyond our current codegen capabilities.
define <4 x i32> @trunc_sext(<4 x i16>* %in) {
; NO_SSE_41-LABEL: trunc_sext:
; NO_SSE_41: # %bb.0:
; NO_SSE_41-NEXT: movq {{.*#+}} xmm0 = mem[0],zero
; NO_SSE_41-NEXT: punpcklwd {{.*#+}} xmm0 = xmm0[0,0,1,1,2,2,3,3]
; NO_SSE_41-NEXT: pslld $24, %xmm0
; NO_SSE_41-NEXT: psrad $24, %xmm0
; NO_SSE_41-NEXT: retq
;
; SSE_41-LABEL: trunc_sext:
; SSE_41: # %bb.0:
; SSE_41-NEXT: pmovzxwd {{.*#+}} xmm0 = mem[0],zero,mem[1],zero,mem[2],zero,mem[3],zero
; SSE_41-NEXT: pslld $24, %xmm0
; SSE_41-NEXT: psrad $24, %xmm0
; SSE_41-NEXT: retq
%load = load <4 x i16>, <4 x i16>* %in
%trunc = trunc <4 x i16> %load to <4 x i8>
%sext = sext <4 x i8> %trunc to <4 x i32>
ret <4 x i32> %sext
}
|
