------- Comment #3 from bonzini at gnu dot org 2009-07-14 12:56 -------
Richard, is your testcase also a regression? In that case the culprit is
mostly
#if 0
/* Disabled to avoid exponential mutual recursion between nonzero_bits
and num_sign_bit_copies. */
if (num_sign_bit_copies (XEXP (x, 0), GET_MODE (x))
== GET_MODE_BITSIZE (GET_MODE (x)))
nonzero = 1;
#endif
in rtlanal.c that makes GCC unable to see through
9 r142:SI=-ltu(r139:SI,r138:SI)
10 r141:SI=-r142:SI
produced by
emit_insn (gen_cstoresi_nltu_thumb1 (scratch, op3, operands[2]));
emit_insn (gen_negsi2 (operands[0], scratch));
--
bonzini at gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |bonzini at gnu dot org
|dot org |
Status|NEW |ASSIGNED
Last reconfirmed|2009-05-21 10:49:12 |2009-07-14 12:56:22
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39715
