Re: your mail

[Michael Matz <matz@suse.de>]

Hi,

On Mon, 23 Feb 2004, kripa shankar wrote:

> ;; Start of basic block 2, registers live: 11 [fp] 13 [sp]
> (note 62 41 45 [bb 2] NOTE_INSN_BASIC_BLOCK)
> (insn 45 62 46 (set (reg/i:SI 0 r0)        (const_int 0 [0x0])) 176 {*movsi_insn} (nil)    (expr_list:REG_EQUAL (const_int 0 [0x0])        (nil)))
> (insn 46 45 76 (use (reg/i:SI 0 r0)) -1 (insn_list 45 (nil))    (nil))
> (insn 76 46 77 (set (reg:SI 7 r7)        (plus:SI (reg:SI 5 r5)            (const_int 2 [0x2]))) -1 (nil)    (nil))
> (insn 77 76 50 (set (reg:SI 6 r6)        (plus:SI (reg:SI 4 r4)            (const_int 2 [0x2]))) -1 (nil)    (nil))
> ;; End of basic block 2
> (note 50 77 63 0 NOTE_INSN_BLOCK_END)
> (note 63 50 0 "" NOTE_INSN_DELETED)
> 
> The instructions inserted are r7 = r5 + 2;r6 = r4 + 2; But the problem
> is that the inserted instructions are not present in both asm file
> (fourth.s) and the output binary file (fourth.o).. I have inserted these
> instructions right after all the optimization passess and before the
> final pass (final.c) where RTL gets converted into Assembly. Kindly help
> me.

There is not enough information.  Where exactly have you added the code to
add those insns?  About which compiler version do you speak?  Produce all 
dump files (-da) and look which dump misses them first.  The problem is, 
that you include those instructions without updating lifeness (i.e. the 
compiler doesn't see, that r6 and r7 really are required after you've set 
them.  So, if there is any pass deleting useless insns after you inserted 
them, they will get deleted.


Ciao,
Michael.