https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85480
Bug ID: 85480
Summary: zero extension from xmm to zmm via _mm512_insert???x?
not optimized
Product: gcc
Version: 8.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: kretz at kde dot org
Target Milestone: ---
Test case (cf. https://godbolt.org/g/p4Kt8X):
#include <x86intrin.h>
__m512 zero_extend2(__m128 a) {
return _mm512_insertf32x4(__m512(), a, 0);
}
__m512d zero_extend2(__m128d a) {
return _mm512_insertf64x2(__m512d(), a, 0);
}
__m512i zero_extend2(__m128i a) {
return _mm512_inserti32x4(__m512i(), a, 0);
}
These 3 functions should compile to `vmovaps %xmm0, %xmm0`, `vmovapd %xmm0,
%xmm0`, and `vmovdqa %xmm0, %xmm0`, respectively.
GCC detects the optimization for the xmm->ymm and ymm->zmm cases already. It's
only missing for the xmm->zmm case.
