Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Andi Kleen
"Steven Bosscher" <[EMAIL PROTECTED]> writes: > On 6/2/06, Davis, Mark <[EMAIL PROTECTED]> wrote: > > Question: does gcc now know the difference between prefetching to cache L1 > > via > > "lfetch", as opposed to prefetching only to level L2 via "lfetch.nt1"? > > The ia64 backend knows the diffe

RE: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Canqun Yang
--- "Davis, Mark" <[EMAIL PROTECTED]>: > Canqun, > > Nice job getting this ready for the current version of gcc! > > Question: does gcc now know the difference between prefetching to cache L1 > via "lfetch", as > opposed to prefetching only to level L2 via "lfetch.nt1"? For floating point >

Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Steven Bosscher
On 6/3/06, Steven Bosscher <[EMAIL PROTECTED]> wrote: > For floating point data, the latter is the only interesting case because float loads only > access the L2. Thus using "lfetch" for floating point arrays will unnecessarily wipe out > the contents of L1. (gcc 3.2.3 only seems to generate

Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Steven Bosscher
On 6/2/06, Davis, Mark <[EMAIL PROTECTED]> wrote: Question: does gcc now know the difference between prefetching to cache L1 via "lfetch", as opposed to prefetching only to level L2 via "lfetch.nt1"? The ia64 backend knows the difference, see the prefetch pattern in ia64.md. But ia64 is the on

RE: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Davis, Mark
Canqun, Nice job getting this ready for the current version of gcc! Question: does gcc now know the difference between prefetching to cache L1 via "lfetch", as opposed to prefetching only to level L2 via "lfetch.nt1"? For floating point data, the latter is the only interesting case because flo

Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Canqun Yang
--- Andrey Belevantsev <[EMAIL PROTECTED]>: > Canqun Yang wrote: > > Hi, all > > > > This patch results a performance increase of 4% for SPECfp2000 and 13% for > > NAS benchmark suite > on > > Itanium-2 system, respectively. More performance increase is hopeful by > > further tuning the > > par

Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Steven Bosscher
On 6/2/06, Canqun Yang <[EMAIL PROTECTED]> wrote: This patch results a performance increase of 4% for SPECfp2000 and 13% for NAS benchmark suite on Itanium-2 system, respectively. More performance increase is hopeful by further tuning the parameters and improving the prefetch algorithm at tree

Re: [patch] Improve loop array prefetch for IA-64

2006-06-02 Thread Andrey Belevantsev
Canqun Yang wrote: Hi, all This patch results a performance increase of 4% for SPECfp2000 and 13% for NAS benchmark suite on Itanium-2 system, respectively. More performance increase is hopeful by further tuning the parameters and improving the prefetch algorithm at tree level. Hi Canqun,