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Subject: Re: Some functions are not inlined by gcc 3.2, resulting code is
	ugly
From: Jussi Laako <jussi.laako@kolumbus.fi>
To: vda@port.imtp.ilyichevsk.odessa.ua
Cc: linux-kernel@vger.kernel.org
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On Sun, 2002-11-03 at 18:17, Denis Vlasenko wrote:

Jump target 17e0 is aligned (with nops):

>     17dd:	88 02                	mov    %al,(%edx)
>     17df:	90                   	nop   =20
>     17e0:	89 d0                	mov    %edx,%eax
>     17e2:	5a                   	pop    %edx

>     17ec:	eb f2                	jmp    17e0 <__constant_memcpy+0x20>

>     17fa:	eb e4                	jmp    17e0 <__constant_memcpy+0x20>

>     1800:	eb de                	jmp    17e0 <__constant_memcpy+0x20>

>     187c:	e9 5f ff ff ff       	jmp    17e0 <__constant_memcpy+0x20>
>     1881:	eb 0d                	jmp    1890 <__constant_memcpy+0xd0>
>     1883:	90                   	nop   =20
...
>     188f:	90                   	nop   =20
>     1890:	c1 e9 02             	shr    $0x2,%ecx
>     1893:	89 d7                	mov    %edx,%edi

And also jump target 1890 is aligned.


I think the penalty of few NOPs is smaller than result of jump to
unaligned address. This is especially true with P4 architecture.


	- Jussi Laako

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