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From: "juzhe.zhong at rivai dot ai" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/111857] New: RISC-V: Failed to vectorize small GNU vector if zvl4096b with fixed-vlmax
Date: Wed, 18 Oct 2023 06:19:56 +0000	[thread overview]
Message-ID: <bug-111857-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111857

            Bug ID: 111857
           Summary: RISC-V: Failed to vectorize small GNU vector if
                    zvl4096b with fixed-vlmax
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: juzhe.zhong at rivai dot ai
  Target Milestone: ---

typedef char vnx16i __attribute__ ((vector_size (16)));

#define MASK_16 12, 13, 14, 15, 12, 13, 14, 15, 12, 13, 14, 15, 12, 13, 14, 15

vnx16i __attribute__ ((noinline, noclone))
test_1 (vnx16i x, vnx16i y)
{
  return __builtin_shufflevector (x, y, MASK_16);
}

If we specify it as -march=rv64gcv
--param=riscv-autovec-preference=fixed-vlmax.
it can vectorize.

But failed to vectorize it with -march=rv64gcv_zvl4096b
--param=riscv-autovec-preference=fixed-vlmax

https://godbolt.org/z/zx816ao5o

             reply	other threads:[~2023-10-18  6:19 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-18  6:19 juzhe.zhong at rivai dot ai [this message]
2023-10-18  6:21 ` [Bug c/111857] " juzhe.zhong at rivai dot ai
2023-10-18 20:11 ` [Bug target/111857] " pinskia at gcc dot gnu.org
2023-10-21  1:25 ` cvs-commit at gcc dot gnu.org
2023-10-21  3:29 ` juzhe.zhong at rivai dot ai

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