public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug target/101022] New: rs6000: __builtin_altivec_vcmpequt expands to wrong pattern
@ 2021-06-10 19:50 wschmidt at gcc dot gnu.org
  2021-06-10 19:52 ` [Bug target/101022] " wschmidt at gcc dot gnu.org
                   ` (5 more replies)
  0 siblings, 6 replies; 7+ messages in thread
From: wschmidt at gcc dot gnu.org @ 2021-06-10 19:50 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101022

            Bug ID: 101022
           Summary: rs6000: __builtin_altivec_vcmpequt expands to wrong
                    pattern
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wschmidt at gcc dot gnu.org
  Target Milestone: ---

This line appears in a recent patch committed this week:

+BU_P10V_AV_2 (VCMPEQUT,                "vcmpequt",     CONST,  eqvv1ti3)       

This builtin should expand to the ISA 3.1 vcmpequq instruction, but this
definition causes it to expand to bitwise equivalence (not-XOR).  That violates
the definition of vec_cmpeq, which must return all 0s or all 1s for each lane
element.  For this type, that means all 0s or all 1s in the entire register.

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2022-01-14 18:39 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-06-10 19:50 [Bug target/101022] New: rs6000: __builtin_altivec_vcmpequt expands to wrong pattern wschmidt at gcc dot gnu.org
2021-06-10 19:52 ` [Bug target/101022] " wschmidt at gcc dot gnu.org
2021-06-10 19:56 ` wschmidt at gcc dot gnu.org
2021-06-10 22:20 ` cel at us dot ibm.com
2021-06-11 14:08 ` wschmidt at gcc dot gnu.org
2021-06-15 15:44 ` cvs-commit at gcc dot gnu.org
2022-01-14 18:39 ` wschmidt at gcc dot gnu.org

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).