[Bug target/18751] [4.0 Regression] ICE in expr.c:5083, profiledbootstrap

[amodra at bigpond dot net dot au]

------- Additional Comments From amodra at bigpond dot net dot au  2004-12-06 11:26 -------
I think this particular problem was introduced with one of Geoff's patches,
http://gcc.gnu.org/ml/gcc-patches/2004-08/msg00022.html

rs6000_mode_dependent_address returns true for LO_SUM addresses, which in turn
makes them not offsettable.  Thus movdi_internal32 won't match DImode gpr stores.
It's clear that LO_SUM addresses can't be offset (since an offset may bump the
final address over a 64k+32k boundary, and the compiler can't know when this
might happen).  Also, the rtl generated by -fprofile-generate looks OK.  I don't
think there's anything wrong with Geoff's patch either, but it's boxed us into a
corner.  A fix that will work (I think) is to limit legitimate_lo_sum_address_p
to 32 bit modes, but that could pessimize all loads and stores of 64 bit values.


-- 
           What    |Removed                     |Added
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                 CC|                            |geoffk at geoffk dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18751