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* [Bug target/99405] New: Rotate with mask not optimized on x86 for QI/HImode rotates
@ 2021-03-05 12:38 jakub at gcc dot gnu.org
  2021-03-05 12:43 ` [Bug target/99405] " jakub at gcc dot gnu.org
                   ` (8 more replies)
  0 siblings, 9 replies; 10+ messages in thread
From: jakub at gcc dot gnu.org @ 2021-03-05 12:38 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99405

            Bug ID: 99405
           Summary: Rotate with mask not optimized on x86 for QI/HImode
                    rotates
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org
                CC: jakub at gcc dot gnu.org, unlvsur at live dot com
        Depends on: 99396
  Target Milestone: ---

+++ This bug was initially created as a clone of Bug #99396 +++

In
unsigned char f1 (unsigned char x, unsigned y) { return (x << (y & 7)) | (x >>
(-y & 7)); }
unsigned short f2 (unsigned short x, unsigned y) { return (x << (y & 15)) | (x
>> (-y & 15)); }
unsigned int f3 (unsigned int x, unsigned y) { return (x << (y & 31)) | (x >>
(-y & 31)); }
unsigned char f4 (unsigned char x, unsigned y) { return (x >> (y & 7)) | (x <<
(-y & 7)); }
unsigned short f5 (unsigned short x, unsigned y) { return (x >> (y & 15)) | (x
<< (-y & 15)); }
unsigned int f6 (unsigned int x, unsigned y) { return (x >> (y & 31)) | (x <<
(-y & 31)); }
unsigned char f7 (unsigned char x, unsigned char y) { unsigned char v = y & 7;
unsigned char w = -y & 7; return (x << v) | (x >> w); }
unsigned short f8 (unsigned short x, unsigned char y) { unsigned char v = y &
15; unsigned char w = -y & 15; return (x << v) | (x >> w); }
unsigned int f9 (unsigned int x, unsigned char y) { unsigned char v = y & 31;
unsigned char w = -y & 31; return (x << v) | (x >> w); }
unsigned char f10 (unsigned char x, unsigned char y) { unsigned char v = y & 7;
unsigned char w = -y & 7; return (x >> v) | (x << w); }
unsigned short f11 (unsigned short x, unsigned char y) { unsigned char v = y &
15; unsigned char w = -y & 15; return (x >> v) | (x << w); }
unsigned int f12 (unsigned int x, unsigned char y) { unsigned char v = y & 31;
unsigned char w = -y & 31; return (x >> v) | (x << w); }
#ifdef __x86_64__
unsigned long long f13 (unsigned long long x, unsigned y) { return (x << (y &
63)) | (x >> (-y & 63)); }
unsigned long long f14 (unsigned long long x, unsigned y) { return (x >> (y &
63)) | (x << (-y & 63)); }
unsigned long long f15 (unsigned long long x, unsigned char y) { unsigned char
v = y & 63; unsigned char w = -y & 63; return (x << v) | (x >> w); }
unsigned long long f16 (unsigned long long x, unsigned char y) { unsigned char
v = y & 63; unsigned char w = -y & 63; return (x >> v) | (x << w); }
#endif

we don't optimize away the and instructions in f{1,2,4,5,7,8,10,11}.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99396
[Bug 99396] std::rotl and std::rotr Does not convert into ROTATE on the gimple
level

^ permalink raw reply	[flat|nested] 10+ messages in thread
end of thread, other threads:[~2022-05-27 18:43 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-05 12:38 [Bug target/99405] New: Rotate with mask not optimized on x86 for QI/HImode rotates jakub at gcc dot gnu.org
2021-03-05 12:43 ` [Bug target/99405] " jakub at gcc dot gnu.org
2021-03-05 12:59 ` ubizjak at gmail dot com
2021-03-05 13:03 ` jakub at gcc dot gnu.org
2021-03-05 14:55 ` unlvsur at live dot com
2021-03-05 14:59 ` jakub at gcc dot gnu.org
2021-03-05 15:06 ` unlvsur at live dot com
2021-03-06 10:13 ` jakub at gcc dot gnu.org
2021-04-27  8:18 ` cvs-commit at gcc dot gnu.org
2022-05-27 18:43 ` roger at nextmovesoftware dot com

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