[Bug target/48806] ICE in reload_cse_simplify_operands, at postreload.c:403

["kkojima at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48806

Kazumoto Kojima <kkojima at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.04.29 00:22:53
                 CC|                            |kkojima at gcc dot gnu.org
     Ever Confirmed|0                           |1

--- Comment #1 from Kazumoto Kojima <kkojima at gcc dot gnu.org> 2011-04-29 00:22:53 UTC ---
Before reload pass, the insns causing problem look like as

...
(insn 131 22 23 4 (set (reg/f:SI 231)
        (reg/v/f:SI 167 [ ctx ])) foo.c:74 176 {movsi_ie}
     (nil))

(insn 23 131 24 4 (set (reg/f:SI 168 [ D.2106 ])
        (mem/s/f/j:SI (post_inc:SI (reg/f:SI 231)) [0 ctx_12->cc_ic+0 S4 A32]))
foo.c:74 176 {movsi_ie}
     (expr_list:REG_INC (reg/f:SI 231)
        (nil)))
...

When reloading, with -O1, IRA gives fr13 as r231 and these insns
are reloaded like as

(insn 131 154 155 3 (set (reg:SI 1 r1)
        (mem/c:SI (plus:SI (reg/f:SI 15 r15)
                (const_int 12 [0xc])) [0 %sfp+-52 S4 A32])) foo.c:74 176 {mo
vsi_ie}
     (nil))

(insn 155 131 156 3 (set (reg:SI 150 fpul)
        (reg:SI 1 r1)) foo.c:74 176 {movsi_ie}
     (nil))

(insn 156 155 157 3 (set (reg/f:SI 77 fr13 [231])
        (reg:SI 150 fpul)) foo.c:74 176 {movsi_ie}
     (nil))

(insn 157 156 159 3 (set (reg:SI 2 r2)
        (reg/f:SI 77 fr13 [231])) foo.c:74 176 {movsi_ie}
     (nil))

(insn 159 157 160 3 (set (reg:SI 2 r2)
        (plus:SI (reg:SI 2 r2)
            (const_int 4 [0x4]))) foo.c:74 35 {*addsi3_compact}
     (nil))

Insn 157 is illegal because SH has no move insns between frN and
rM directly and the error occurs.
It seems this issue is two-fold, though both are beyond me.
The one problem would be that reload doesn't validate some move
insns generated during POST_INC/PRE_DEC handling.  The other one
is that RA chooses a floating point register as the pointer
register with -O1.  The later looks like the same issue as PR48596.