PowerPC emulation on x86 possible?

[bloodline]

@minator

I assure you that running a PPC at the same Clock speed as a Modern x86, will result in a very similar performance.

The chips are simply not that different!!

With out of order execution, then use Register Renaming, which allows for many more registers than architeurally avaiable. I would like to note that many "RISC" designs use Register windowing to limit the numer of Registers that the Programmer can see at any one time...

What you fail to understand is that All CPU designers use the same tricks to achieve speedups...

Oh, and if you want to say that the Alpha stoped being "RISC" at some point, then I would note that the PPC is far less "RISC", than just about any other RISC chip on the planet.

-Edit- "Altivec will out gun a P4" - you really have no clue what you are talking about... ok we get technical... look up instructions per cycle for the Altivec and then look at the instructions per cycle for SEE2 (etc...), then look at how many cycles per second the G4 (~1Ghz, since the) and the P4 (~3Ghz) run at...  please don't be stupid.

[Hammer]

In terms of your laptop, efficiency is a big deal.

What about the efficiency in using the money you have?

If the CPU is effieient it'll give you longer battery life. Do you think a 50W difference is worth it for perhaps 2X the speed? The G4 uses 20W and thats an old version, the modern low voltage G4s go down to 7.5 Watts at 1GHz, Compared to the P4 which uses 70 Watts.

Try against “Pentium M” i.e. Intel’s X86 processor designed solely for light and thin markets. Note that “Pentium M” @1.6Ghz integer performance is  roughly equal to Pentium VI @ 2.5Ghz. Intel is offering two different X86 cores in the market place i.e.
1. X86 core that is IPC bias e.g. Pentium M.
2. X86 core that is clockspeed bias e.g. Pentium 4.

PS; It didn’t stop PC vendors in using Pentium M for blade servers.

And for your application the fact the G4 has Altivec will make quite a difference, on Altivec code the G4 it's quite probably to outgun the P4 even at 3GHz - because the design is less efficient.

Note that the Pentium VI was built for clock speed first than IPC second.  The Altivec doesn’t rescue PowerMac G4 @1.4Ghz in every cases from being last in graphic extensive applications e.g. modern 3D games.

References;
http://www.barefeats.com//p4game.html

Note that next generation PowerMac G5 should have beaten the superseded AMD K7 Athlon MP@2.1Ghz(DDR266 FSB) due to G5’s  “superior” DDR1000 FSB speed.

For completeness and optimised for gamming purposes, the Athlon MP’s chipset in that case was not even
1. AthlonXP3200+/NVIDIA’s nForce2 400 Ultra
2. Athlon FX51/64 3200+
3. Pentium VI@3.2Ghz/Extreme Edition.
 
PS; There are two types of Athlon MP @2.1 Ghz i.e.
1. Athlon MP 2600+ @2.1Ghz (use in barefeats test)
2.  Athlon MP 2800+ @2.1Ghz

Reference for Athlons MP PR ratings;
http://www.pathwayexpress.com/catviewL.cfm?cid=CPU

If the CPU has Out of Order execution the smaller number of registers is going to have a big impact on the design of that stage making it considerably more complex.

Register renaming schemes is the way to expand the limited registers of the X86-32 limitations.  

[Hammer]

The P4 and Athlon are both very fast CPUs, but in order to get that speed they have to do a lot of work

Note that IBM's PowerPC 970 and AMD's Athlon 64 3200+ are both clocked at 2.0Ghz. AMD's Athlon 64 3200+ pretty much rivals/beats the Pentium VI @3.0Ghz in games (needs PIV @3.2C Ghz ).

In general performance; the Athlon 64 3200+ > Athlon XP 3200+/nForce II 400 Ultra**.

**Chipset type is important with AMD's K7 processors (e.g. in general, signal channel nVidia nForce2 400 > VIA KT600 > KT400A).  

and consume a lot of power.

Note that the IBM PowerPC 970 has ~52~55million transistors, which is in the ball park of AMD’s Athlon  XP-M Barton Core in regards thermal characteristics (without taking into an account of Speed-Step like technologies).  

If IBM put the effort into design they could produce a faster processor in the same silicon technology. I don't kow if the 970 reaches that goal (at least with current compilers) but I expect the next gen (due next summer) may do so.

In terms of overall benchmarks results and even with superior FSB speed (in the case of K7); IBM's PPC 970 is struggling to beat/surplus the similar clocked late model AMD processors.  

[Terminills]

:edit:
posted by accident

[Methuselas]

when people starts a thread like this , just when things starts to look better, well its just like amithlon in 2001, it made people LEAVE!

@Lempkee,

Funny, I bought this for under $200. That brought money to Amiga. The REGGED copy of Ibrowse2.3 I have wasn't free either.

Hmm....I have a FAST amiga, faster that one I've EVER had and all for under 300$. You can't even get a decent a1200 new for that price. (oh, and I'm going to stop you right now before you embarass yourself with 'you can get yourself an a1200 with the magic pack bundle and a 200MB HDD for that price')

So, I supported a software market that is OBVIOUSLY dying, but I must STILL love, 'cos I bought them in the first place and you CONDEMN me for using an X86. That's just sad, Lempkee..... just sad.

I haven't bought an AmigaOne yet and I'm not going to, until OS4 is released. Quite frankly, the 'screenshots' that Hyperion have released are crap, 'cos they don't show anything, but eyecandy and I'm not about to shell out 800$ for a Mobo that has NO operating system. (You yourself, said you won't use anything but Amiga's OS, so I KNOW you're not using the 'geek' os of Linux.)

Why did you even bother to come in here? The people that posted would like to see if this is a viable project. You came in here, soley to B!TCH about 'traitors' to Amiga. If anything, it is YOU who is the traitor and the one leaving Amiga. Anyone of us here either owns or at one time owned an Amiga, but times change and so do people. Just because YOU decided to think of your Amiga like many people do a 62 VW Beetle, gives you NO right to judge others, simply 'cos they decided to move on and 'buy a new car'.

I'm suprised you even bought an AmigaOne. After all, it doesn't have custom chips. It's not a real 'amiga' or do you admit that amiga is 'only a name.'

I think you owe some people on this thread an apology. :-x

[bloodline]

The thing I find most strange about people like Lempkee, is their unrelenting desire to say x86 this and x86 that... and how crap the PC is, etc... then they praise a machine that shares 95% of it's components with a PC (the only difference being the CPU and the Northbridge)!

I have not yet heard a logical and resonable reason not to use the x86 CPU, by the same token I have not heard a good reason not to use PPC. There is no good reason to slag other people off because they have weighed up the pros and cons and chosen one procesor or the other!

I must say that I do feels a strng affinity for the 68K (I grew up with it, I learned to program it, It's my "first love" CPU), but there comes a point when you have to say, "It's no longer useful". CPU's are commodities, they are not special they are homoginising. in 50 years (if we still use them) Microprocessors will all look the same.

I really can't get the idea that Amiga = AmigaONE either... the AmigaONE is just commodity hardware, it's no different to the Pegasos or even a PC... And that is a good thing since we all get to choose what we want, and the hardware isn't dramatically different.

Rant, rant....

To get back to the point, I am as interested to see PPC emulation on the x86 as I am to see x86 emulation on the PPC.

Oh, and before I forget, Lempkee, whay don't Hyperion "certify" a PPC emulator for the x86, that can run OS4... then they could sell more, you really should think before you post.

[Paul_Gadd]

Bad evil Amithlon/UAE  users plotting to destroy the Amiga church, we must protect our new hardware what costs 5x as much and twice as slow as a adverage x86 board.

How dare you people use these evil emulators on machines what are affordable when you should support the cause by purchasing rip off hardware from rip off companies what will dominate the world.

DIE x86 DIE--------------------------->  RIP OFF PPC FOREVER!

[Methuselas]

How dare you people use these evil emulators on machines what are affordable when you should support the cause by purchasing rip off hardware from rip off companies what will dominate the world.

:roflmao:

HAHAHAHAHA A bit blunt and extreme, but funny as hell!

Just remember Paul, we may be evil, but evil spelled backwards is LIVE and we all want to do that.

Methuselas wrote:

How dare you people use these evil emulators on machines what are affordable when you should support the cause by purchasing rip off hardware from rip off companies what will dominate the world.

:roflmao:

HAHAHAHAHA A bit blunt and extreme, but funny as hell!

Just remember Paul, we may be evil, but evil spelled backwards is LIVE and we all want to do that.

And Evian spelt backwards is Naive.  Do you drink it? ;-)

[minator]

What about the efficiency in using the money you have?

You get what you pay for  :-D

try against “Pentium M” i.e. Intel’s X86 processor designed solely for light and thin markets.

It'll go against the lowest G5 which uses pretty similar power.  The difference is the Pentium M was specifically designed for low power whereas the G5 wasn't.

Note that the Pentium VI was built for clock speed first than IPC second.  The Altivec doesn’t rescue PowerMac G4 @1.4Ghz in every cases from being last in graphic extensive applications e.g. modern 3D games.

I never said it did, it'll only pull ahead on Altivec stuff (i.e. audio effects) otherwise the P4 will run faster.  Motorola gave up on the desktop market some time ago so these are basically embedded chips designed for low power.

References;
http://www.barefeats.com//p4game.html

Running benchmaks which test the graphics system, does not say much about the CPU.  Unfortunately thats exactly what barefeats did and produced useless results as a result.

Any tests I've seen put the G5 in line with the top end P4s, in front sometimes, behind in others.
I've yet so see anything directly comparing the G5 and the Opteron / Athlon64 but I suspect the AMD may have the overall lead.

That said neither the AMD or the G5 have good compilers yet and have anytime soon, it'll be interesting the see the results then.

Quote:

If the CPU has Out of Order execution the smaller number of registers is going to have a big impact on the design of that stage making it considerably more complex.

Register renaming schemes is the way to expand the limited registers of the X86-32 limitations.

Not quite, it's there to boost IPC.  It doesn't give you any extra registers the developer can actually see.  Everything is still compiled to use the 8 "architectural" registers so the OOO hardware has to map all the rename registers onto them.

A big difference between PPC and x86 is the PPC has to work less to increase the IPC.  The Pentium 4 has 128 rename registers, the G5 has less than half (48) yet the G5 at a 50% lower clock rate is performing in line with the P4.