https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71559
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2016-06-17
CC| |jakub at gcc dot gnu.org,
| |uros at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I'd say it is a bug in ix86_fp_cmp_code_to_pcmp_immediate that it handles only
a small portion of the FP comparison codes, while VCMPP[SD] instructions should
be able to handle everything needed.
But, I'm also surprised where the values in that function come from.
Looking at the D modifier expansion in i386.c that is used for AVX vcmp, I see
that:
code %D3 emits corresponding imm ix86_fp_cmp_code_to_pcmp_immediate
UNEQ eq_us 0x18 ICE
EQ eq 0 8
UNLT nge 9 ICE
LT lt 1 0x19
UNLE ngt 0xa ICE
LE le 2 0x1a
UNORDERED unord 3 ICE
LTGT neq_oq 0xc ICE
NE neq 4 4
GE ge 0xd 0x15
UNGE nlt 5 ICE
GT gt 0xe 0x16
UNGT nle 6 ICE
ORDERED ord 7 ICE
So, there is agreement only on NE and nothing else.