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Re: loop optimizer naivety


In message <200309231029.33653.ebotcazou@libertysurf.fr>, Eric Botcazou writes:
 >> If you could verify that sequence of events it would be helpful in at
 >> least determining that LCM is operating properly.  To do this you'd put
 >> a breakpoint just before this hunk of code in gcse.c and dump the RTL
 >> to a file:
 >
 >The log file is sufficient I think:
 >
 >PRE:  store updated with reaching reg (reg:SI 185):
 >	(insn 610 609 765 3 0x40a5565c (set (mem/f:SI (plus:SI (reg/f:SI 20 fra
 >me)
 >                                (const_int -100 [0xffffff9c])) [5 S4 A32])
 >                        (reg:SI 173)) 38 {*movsi_1} (nil)
 >                    (expr_list:REG_EQUAL (plus:SI (reg:SI 161)
 >                            (const_int 1 [0x1]))
 >                        (nil)))
 >
 >LOCAL COPY-PROP: Replacing reg 185 in insn 610 with reg 173
OK.  Thanks.    That verifies that PRE/LCM and copy propagation are doing
their job properly and that the loop optimizer is what needs to be fixed.
jeff


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