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Subject: [Bug tree-optimization/44977] [4.4/4.5/4.6 Regression] ice in propagate_rhs_into_lhs, at tree-ssa-dom.c:2728
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From: "rguenth at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
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------- Comment #3 from rguenth at gcc dot gnu dot org  2010-07-20 11:20 -------
#1  0x0000000000aeab84 in propagate_rhs_into_lhs (stmt=0x7ffff5b4d370, 
    lhs=0x7ffff5afc738, rhs=0x7ffff5afc738, interesting_names=0x17b93c8)
    at /space/rguenther/src/svn/trunk/gcc/tree-ssa-dom.c:2728
2728          gcc_assert (!all || has_zero_uses (lhs));
(gdb) p all
$1 = 1 '\001'
(gdb) p lhs
(gdb) call debug_immediate_uses_for (lhs)
g_67.1_6 : --> single use.
g_67.1_6 = g_67.1_6;


We have

<bb 9>:
  # l_85_37 = PHI <0(9), 0(4)>
  # prephitmp.12_36 = PHI <g_67.1_6(9), g_67.1_7(4)>
  g_67.1_6 = prephitmp.12_36 ^ l_85_37;
  goto <bb 9>;

and eliminate_degenerate_phis replaces it with the above through the
intermediate

<bb 9>:
  # prephitmp.12_36 = PHI <g_67.1_6(9)>
  g_67.1_6 = prephitmp.12_36;
  goto <bb 9>;

I have a patch.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44977