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From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114908] fails to optimize avx2 in-register permute written with std::experimental::simd
Date: Mon, 06 May 2024 10:12:53 +0000	[thread overview]
Message-ID: <bug-114908-4-VqZaHu9Dhs@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-114908-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114908

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
Thanks, and it might be enough to handle

typedef unsigned long V [[gnu::vector_size(32)]];

V load3(const unsigned long* ptr)
{
  V ret = {};
  __builtin_memcpy(&ret, ptr, 3 * sizeof(unsigned long));
  return ret;
}

where with -O2 .optimized still has

  <bb 2> [local count: 1073741824]:
  ret = { 0, 0, 0, 0 };
  __builtin_memcpy (&ret, ptr_3(D), 24);
  _5 = ret;
  ret ={v} {CLOBBER(eos)};
  return _5;

and thus 'ret' not promoted to a register.

  parent reply	other threads:[~2024-05-06 10:12 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-01 16:05 [Bug target/114908] New: " lee.imple at gmail dot com
2024-05-01 17:21 ` [Bug target/114908] " pinskia at gcc dot gnu.org
2024-05-01 17:31 ` [Bug tree-optimization/114908] " pinskia at gcc dot gnu.org
2024-05-02 11:12 ` rguenth at gcc dot gnu.org
2024-05-06  9:05 ` mkretz at gcc dot gnu.org
2024-05-06  9:16 ` rguenther at suse dot de
2024-05-06 10:00 ` mkretz at gcc dot gnu.org
2024-05-06 10:12 ` rguenth at gcc dot gnu.org [this message]
2024-05-06 10:30 ` mkretz at gcc dot gnu.org
2024-05-07  3:09 ` lee.imple at gmail dot com

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