Comment 2 for bug 693502

I think it's just the 2nd call that's wrong; the calls are to norm2 all based off the same matrix, with the first call being at the base, the 2nd at base+12 and the 3rd at base+24; it looks to me like some of the accesses in the 2nd call are being made to base rather than base+12 and then shared with the loads from the 1st call.

From the rtl dumps, I think ns.c.169r.loop2_done is ok, but ns.c.193r.split2 is bad.

I'm not sure about ns.c.184r.subreg2 ; it looks like it's trying to post increment 12 onto the address but then I suspect it's that post increment that isn't being properly followed through:

-----------------------------------------------------------------
(insn 2430 105 106 2 ns.c:1677 (set (reg/f:SI 571 [ D.9349 ])
        (reg/v/f:SI 849 [ box ])) 591 {*thumb2_movsi_vfp} (nil))

(insn 106 2430 107 2 ns.c:1677 (set (reg:SF 861)
        (mem/s/j:SF (post_modify:SI (reg/f:SI 571 [ D.9349 ])
                (plus:SI (reg/f:SI 571 [ D.9349 ])
                    (const_int 12 [0xc]))) [0 S4 A32])) 598 {*thumb2_movsf_vfp} (expr_list:REG_INC (reg/f:SI 571 [ D.9349 ])
        (nil)))

(insn 107 106 109 2 ns.c:1677 (set (mem/s/j:SF (plus:SI (reg/f:SI 25 sfp)
                (const_int -12 [0xfffffffffffffff4])) [0 box_size+0 S4 A32])
        (reg:SF 861)) 598 {*thumb2_movsf_vfp} (nil))

(insn 109 107 110 2 ns.c:1677 (set (reg:SF 862)
        (mem/s/j:SF (plus:SI (reg/f:SI 571 [ D.9349 ])
                (const_int 4 [0x4])) [0 S4 A32])) 598 {*thumb2_movsf_vfp} (nil))

-----------------------------------------------------------------

then later we have:
(insn 131 129 133 4 vec.h:355 (set (reg:SF 389 [ D.11242 ])
        (mem:SF (plus:SI (reg/v/f:SI 849 [ box ])
                (const_int 12 [0xc])) [0 S4 A32])) 598 {*thumb2_movsf_vfp} (nil))

(insn 133 131 134 4 vec.h:355 (set (reg:SF 396 [ D.11235 ])
        (mem:SF (plus:SI (reg/f:SI 571 [ D.9349 ])
                (const_int 8 [0x8])) [0 S4 A32])) 598 {*thumb2_movsf_vfp} (nil))

(note 134 133 135 4 NOTE_INSN_DELETED)

(insn 135 134 136 4 vec.h:355 (set (reg:SF 869)
        (mult:SF (reg:SF 862)
            (reg:SF 862))) 615 {*mulsf3_vfp} (expr_list:REG_DEAD (reg:SF 862)
        (nil)))
-----------------------------------------------------------------

and I believe that insn 133/131/134 should be using the value from box+12+8, and insn 135 is uisng the SF 862 which
I believe should be the value from box+12+4 which will only happen if that post inc happens.

Dave