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From: "falk at debian dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/17264] [hppa] Missing address increment optimization for fp load/stores
Date: Sun, 24 Sep 2006 19:52:00 -0000	[thread overview]
Message-ID: <20060924195203.10788.qmail@sourceware.org> (raw)
In-Reply-To: <bug-17264-581@http.gcc.gnu.org/bugzilla/>



------- Comment #1 from falk at debian dot org  2006-09-24 19:52 -------
For this test case:

void f(double *pds, double *pdd, unsigned long len) {
  while (len >= 8*sizeof(double)) {
    register double r1,r2,r3,r4;
    r1 = *pds++;
    r2 = *pds++;
    r3 = *pds++;
    r4 = *pds++;
    *pdd++ = r1;
    *pdd++ = r2;
    *pdd++ = r3;
    *pdd++ = r4;
  }
}

gcc starting from 4.0 produces this:

.L3:
        fldds -16(%r26),%fr22
        fldds -8(%r26),%fr23
        fldds 0(%r26),%fr24
        fldds 8(%r26),%fr25
        ldo 32(%r26),%r26
        fstds %fr22,-16(%r25)
        fstds %fr23,-8(%r25)
        fstds %fr24,0(%r25)
        fstds %fr25,8(%r25)
        b .L3

which I suspect is actually better, since it avoids dependencies between the
loads. But I'm not familiar with hppa, can anybody comment?


-- 

falk at debian dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|                            |3.4.2 4.1.2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17264


       reply	other threads:[~2006-09-24 19:52 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-17264-581@http.gcc.gnu.org/bugzilla/>
2006-09-24 19:52 ` falk at debian dot org [this message]
2006-09-24 22:15 ` dave at hiauly1 dot hia dot nrc dot ca
2006-09-24 23:48 ` randolph at tausq dot org
2006-09-24 23:49 ` tausq at debian dot org
2004-09-01 18:22 [Bug rtl-optimization/17264] New: " tausq at debian dot org
2004-09-01 18:53 ` [Bug rtl-optimization/17264] " danglin at gcc dot gnu dot org

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