]> xenbits.xensource.com Git - xen.git/commit
x86: also suppress use of MMX insns
authorJan Beulich <jbeulich@suse.com>
Wed, 20 Jul 2022 13:48:49 +0000 (15:48 +0200)
committerJan Beulich <jbeulich@suse.com>
Wed, 20 Jul 2022 13:48:49 +0000 (15:48 +0200)
commit6fe2e39a0243bddba60f83b77b972a5922d25eb8
tree834b20b6efc8bd2d6bfa173c58e55a85183d0ba1
parentd620c66bdbe5510c3bae89be8cc7ca9a2a6cbaba
x86: also suppress use of MMX insns

Passing -mno-sse alone is not enough: The compiler may still find
(questionable) reasons to use MMX insns. In particular with gcc12 use
of MOVD+PUNPCKLDQ+MOVQ was observed in an apparent attempt to auto-
vectorize the storing of two adjacent zeroes, 32 bits each.

Reported-by: ChrisD <chris@dalessio.org>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
xen/arch/x86/arch.mk