https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80304
Bernd Edlinger <bernd.edlinger at hotmail dot de> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |bernd.edlinger at hotmail dot
de
--- Comment #17 from Bernd Edlinger <bernd.edlinger at hotmail dot de> ---
(In reply to Thomas Koenig from comment #15)
> Also fails on powerpc64-unknown-linux-gnu.
>
> r239317 works, r239326 fails, and also appears to be the only
> patch in the vicinity that does anything about loops.
>
> Could this be the cause?
>
> Author: edlinger
> Date: Fri Aug 12 19:30:39 2016
> New Revision: 239426
>
> URL: https://gcc.gnu.org/viewcvs?rev=239426&root=gcc&view=rev
> Log:
> 2016-08-12 Bernd Edlinger <bernd.edlin...@hotmail.de>
>
> PR tree-optimization/71083
> * tree-predcom.c (ref_at_iteration): Use a COMPONENT_REF for the
> bitfield access when possible.
>
> Modified:
> trunk/gcc/ChangeLog
> trunk/gcc/tree-predcom.c
I really doubt that, because that optimization pass is only used at -O3.
What I can see is that at -O1 -fno-inline
the *.optimized simply does not initialize i:
sub ()
{
unsigned int ivtmp.38;
integer(kind=4) j.28;
real(kind=4) D.3534;
real(kind=4) D.3527;
struct __st_parameter_dt dt_parm.4;
integer(kind=4) j.1;
integer(kind=4) i.0;
integer(kind=8) _2;
integer(kind=8) _3;
real(kind=4) _7;
real(kind=4) _8;
real(kind=4) _13;
real(kind=4) _15;
real(kind=4) _24;
real(kind=4) val.8_25;
struct FRAME.test * _26;
sizetype _39;
real(kind=4) val.5_48;
real(kind=4) val.8_55;
real(kind=4) val.5_71;
real(kind=4) _72;
sizetype _76;
real(kind=4) _101;
real(kind=4) _103;
real(kind=4) _113;
real(kind=4) val.8_114;
real(kind=4) _116;
real(kind=4) val.8_117;
real(kind=4) _125;
real(kind=4) val.5_126;
real(kind=4) _128;
real(kind=4) val.5_129;
<bb 2> [6.83%]:
CHAIN.19_29(D)->a = {};
CHAIN.19_29(D)->b = {};
j.1 = 0;
<bb 3> [13.67%]:
# ivtmp.38_68 = PHI <ivtmp.38_1(3), 0(2)>
j.28_86 = (integer(kind=4)) ivtmp.38_68;
_2 = (integer(kind=8)) j.28_86;
_3 = _2 * 2;
_101 = add (&i.0);
so it is clear why that can not work.
at .gimple it was initialized:
sub ()
{
logical(kind=1) D.3551;
logical(kind=1) D.3554;
a = {};
b = {};
{
integer(kind=4) i.0;
integer(kind=4) j.1;
try
{
{
integer(kind=4) count.2;
integer(kind=4) count.3;
j.1 = 0;
count.3 = 2;
<D.3550>:
_1 = count.3 <= 0;
D.3551 = ANNOTATE (_1, 0);
if (D.3551 != 0) goto L.3; else goto <D.3552>;
<D.3552>:
i.0 = 0;
count.2 = 2;
<D.3553>:
_2 = count.2 <= 0;
D.3554 = ANNOTATE (_2, 0);
if (D.3554 != 0) goto L.2; else goto <D.3555>;
<D.3555>:
j.12_3 = j.1;
_4 = (integer(kind=8)) j.12_3;
_5 = _4 * 2;
i.13_6 = i.0;
_7 = (integer(kind=8)) i.13_6;
_8 = _5 + _7;
_9 = add (&i.0);
