https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106038
Bug ID: 106038
Summary: x86_64 vectorization of ALU ops using xmm registers
prematurely
Product: gcc
Version: 13.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: goldstein.w.n at gmail dot com
Target Milestone: ---
See: https://godbolt.org/z/YxWEn6Y65
Basically in all cases where the total amount of memory touched is <= 8 bytes
(word size) the vectorization pass is choosing to inefficiently use xmm
registers to vectorize the unrolled loops.
GPRs (as GCC <= 9.5 was doing) is faster / less code size.
Related to: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106022
