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From: "mcolavita at fb dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/98335] [9/10/11 Regression] Poor code generation for partial struct initialization
Date: Thu, 17 Dec 2020 16:19:41 +0000	[thread overview]
Message-ID: <bug-98335-4-xUP9RffLzt@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-98335-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98335

--- Comment #1 from Michael Colavita <mcolavita at fb dot com> ---
A similar problem appears to occur for the following example:

  struct Data {
    long a;
    union {
      long u;
      struct {
        char b;
        char pad[3];
      };
    };
  };

  Data val(long d, long e) {
    return { d, e };
  }

Yielding:

    movq            %rdi, %xmm0
    movq            %rsi, %xmm1
    punpcklqdq      %xmm1, %xmm0
    movaps          %xmm0, -56(%rsp)
    movq            -56(%rsp), %rax
    movq            -48(%rsp), %rdx
    ret

  reply	other threads:[~2020-12-17 16:19 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-16 22:02 [Bug rtl-optimization/98335] New: " mcolavita at fb dot com
2020-12-17 16:19 ` mcolavita at fb dot com [this message]
2021-01-04 15:40 ` [Bug tree-optimization/98335] " rguenth at gcc dot gnu.org
2021-01-06 11:01 ` ebotcazou at gcc dot gnu.org
2021-01-20  9:51 ` jakub at gcc dot gnu.org
2021-01-21 11:27 ` jakub at gcc dot gnu.org
2021-06-01  8:19 ` [Bug tree-optimization/98335] [9/10/11/12 " rguenth at gcc dot gnu.org
2022-03-07 13:01 ` roger at nextmovesoftware dot com
2022-03-11 17:53 ` cvs-commit at gcc dot gnu.org
2022-03-11 17:59 ` cvs-commit at gcc dot gnu.org
2022-03-14 18:44 ` roger at nextmovesoftware dot com

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