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Re: gcc 3.1 is still very slow, compared to 2.95.3


   From: Neil Booth <neil@daikokuya.demon.co.uk>
   Date: Sun, 19 May 2002 08:07:03 +0100
   
   Results John posted had memset very high on the list, so I suspect
   someone is.  I think every tree and rtx allocated is memset to
   zero.

What overkill, it's clearing out one word. 

When optimizing, GCC should turn that into an inline
store into the first word of the rtx though....

(Dave checks...)

Yes, it does optimize this, but into 3 byte stores.  One of
which overlaps with the PUT_CODE (rt, code) rtx_alloc does.
:-(

On Sparc this is:

	stb	%g0, [%rt + 1]
	sth	code, [%rt]
	stb	%g0, [%rt + 2]
	stb	%g0, [%rt + 3]

When it should be optimized into:

	sth	code, [%rt]
	sth	%g0, [%rt + 2]


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