On Aug 10, 2012, at 4:13 PM, Dave McGuire wrote:
On 08/10/2012 04:07 PM, Paul_Koning at Dell.com wrote:
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
What target architecture are you compiling for?
x86_64-linux. And x86_64-darwin.
GCC is known to produce very good code for x86_64. I think it might
be worth giving LLVM a try, but I don't think you'll get quite the
output quality of GCC.
Try adding -fomit-frame-pointer; that will free up a register, which
is pretty important on register-starved architectures such as x86 and
x86_64. (depending on your -O<n> level, it might already be turned on
though)
According to the manpage, that's already the default as of GCC V4.6. I'm currently doing some tests with GCC 4.7.0, the latest release.
paul
On 08/10/2012 04:07 PM, Paul_Koning at Dell.com wrote:
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
What target architecture are you compiling for?
x86_64-linux. And x86_64-darwin.
GCC is known to produce very good code for x86_64. I think it might
be worth giving LLVM a try, but I don't think you'll get quite the
output quality of GCC.
Try adding -fomit-frame-pointer; that will free up a register, which
is pretty important on register-starved architectures such as x86 and
x86_64. (depending on your -O<n> level, it might already be turned on
though)
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
On Aug 10, 2012, at 4:07 PM, <hvlems at zonnet.nl>
wrote:
Correct, Windows started off on four platforms so the intimacy of VMS with the VAX was just not there. But VMS was a lot farther away from Alpha too.
I don't think that's accurate.
Most operating systems are not closely tied to a specific platform. And in the case of VMS, the Alpha architecture had some specific attributes that were meant to make porting VMS easier.
paul
Correct, Windows started off on four platforms so the intimacy of VMS with the VAX was just not there. But VMS was a lot farther away from Alpha too.
The reason support for Windows was dropped for all platforms other than IA32 and IA64 indicates that it is too costly if not impossible to engineer.
After all these years Windows settled nicely on IA32.
What Microsoft probably lacks is DEC's compiler architects. Those guys live with Intel now and performance these days is very much their line of business.
It wouldn't surprise me if Intel and Microsoft did do a little bit of joint engineering since 1998.
-----Original Message-----
From: Phil Mendelsohn <phil at rephil.org>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 13:29:06
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
On 10/08/2012 10:51 AM, hvlems at zonnet.nl wrote:
Windows is a relative of vms, an ugly cousin but still family. Its growth is stunted, Windows 7 is the fifth version after W 3.5. VMS grew a lot faster, with more (end user) functionalty, more stability during its first two decades.
Even then Windows 5.1 (aka XP) is stable and useful. Vista wasn't then again VMS 6.1 wasn't that mature either...
But VMS had the advantage that it and the processor (VAX) that ran it
were designed in concert. x86 architecture and Windows are more a case
of being cobbled together iteratively and separately.
--
"Worry is a misuse of imagination." -- Some Guy Called Dan Zadra
On Aug 10, 2012, at 4:05 PM, Dave McGuire wrote:
On 08/10/2012 02:37 PM, Paul_Koning at Dell.com wrote:
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
What target architecture are you compiling for?
x86_64-linux. And x86_64-darwin.
paul
I suppose I could try llvm for Linux, I'm not sure if that exists on a Mac. But gcc is what I know. And it seems to do a pretty good job optimizing. For one thing, a lot of people (a number of them Intel employees) have worked hard on the Intel back end.
paul
On Aug 10, 2012, at 3:58 PM, <hvlems at zonnet.nl>
wrote:
Is gcc the only option you've got Paul?
Gcc must satisfy a lot of terget platforms, may be optimal gets defined differently?
-----Original Message-----
From: <Paul_Koning at Dell.com>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 18:37:47
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
paul
On Aug 10, 2012, at 11:51 AM, <hvlems at zonnet.nl>
<hvlems at zonnet.nl> wrote:
Paul, so the makefile sets the compiler flags, right? So it might be worth figuring out how much effort the compiler puts in optimizing its output.
Windows is a relative of vms, an ugly cousin but still family. Its growth is stunted, Windows 7 is the fifth version after W 3.5. VMS grew a lot faster, with more (end user) functionalty, more stability during its first two decades.
Even then Windows 5.1 (aka XP) is stable and useful. Vista wasn't then again VMS 6.1 wasn't that mature either...
Hans
-----Original Message-----
From: <Paul_Koning at Dell.com>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 14:28:45
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
In my case, gcc with the default makefile. I don't use VC (or the OS it runs on) unless serious force is applied...
paul
On Aug 10, 2012, at 3:02 AM, <hvlems at zonnet.nl>
wrote:
How was simh compiled? I used Visual C and the difference between running the compiler with optimization on or off made quite a difference for the generated code. And gcc might compile even faster codefiles.
Hans
-----Original Message-----
From: Sampsa Laine <sampsa at mac.com>
Sender: owner-hecnet at Update.UU.SE
Date: Thu, 09 Aug 2012 23:07:24
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
Why is SIMH so slow though?
As far as I can understand, one MIPS is roughly one VUPS, correct?
So how come I get 14 VUPS on the same host running SIMH whilst my Hercules install peaks at 180?
Are the architectures that different (obviously they are) or what is it?
Sampsa
On 08/10/2012 02:37 PM, Paul_Koning at Dell.com wrote:
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
What target architecture are you compiling for?
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
On 08/10/2012 03:58 PM, hvlems at zonnet.nl wrote:
Is gcc the only option you've got Paul?
Gcc must satisfy a lot of terget platforms, may be optimal gets defined differently?
Pardon me for jumping in here, but I know something about this part.
GCC's code generation back-end is very tightly tuned for the target
processor. C code (or C++, or FORTRAN, ADA, Pascal, or any other
language GCC supports) is compiled to an intermediate RTL (register
transfer language) and then passed to the code generation back-end.
Various types of optimization, some language-specific and some not, some
target-specific and some not, are applied at various stages.
The end result is a situation in which the quality of the emitted
executable code for one architecture typically does not suffer when
another has had improvements made to it.
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
Is gcc the only option you've got Paul?
Gcc must satisfy a lot of terget platforms, may be optimal gets defined differently?
-----Original Message-----
From: <Paul_Koning at Dell.com>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 18:37:47
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
paul
On Aug 10, 2012, at 11:51 AM, <hvlems at zonnet.nl>
<hvlems at zonnet.nl> wrote:
Paul, so the makefile sets the compiler flags, right? So it might be worth figuring out how much effort the compiler puts in optimizing its output.
Windows is a relative of vms, an ugly cousin but still family. Its growth is stunted, Windows 7 is the fifth version after W 3.5. VMS grew a lot faster, with more (end user) functionalty, more stability during its first two decades.
Even then Windows 5.1 (aka XP) is stable and useful. Vista wasn't then again VMS 6.1 wasn't that mature either...
Hans
-----Original Message-----
From: <Paul_Koning at Dell.com>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 14:28:45
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
In my case, gcc with the default makefile. I don't use VC (or the OS it runs on) unless serious force is applied...
paul
On Aug 10, 2012, at 3:02 AM, <hvlems at zonnet.nl>
wrote:
How was simh compiled? I used Visual C and the difference between running the compiler with optimization on or off made quite a difference for the generated code. And gcc might compile even faster codefiles.
Hans
-----Original Message-----
From: Sampsa Laine <sampsa at mac.com>
Sender: owner-hecnet at Update.UU.SE
Date: Thu, 09 Aug 2012 23:07:24
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
Why is SIMH so slow though?
As far as I can understand, one MIPS is roughly one VUPS, correct?
So how come I get 14 VUPS on the same host running SIMH whilst my Hercules install peaks at 180?
Are the architectures that different (obviously they are) or what is it?
Sampsa
Yes, the makefile sets the optimize flags. It tells it to optimize pretty hard, but I'm redoing some tests with a later version. I'm also going to try (first time I've done that) profile directed optimizing.
The simh code at one point used inline, but not any longer. It may be relying on recent compilers to do that automaticallly, I'll find out.
paul
On Aug 10, 2012, at 11:51 AM, <hvlems at zonnet.nl>
<hvlems at zonnet.nl> wrote:
Paul, so the makefile sets the compiler flags, right? So it might be worth figuring out how much effort the compiler puts in optimizing its output.
Windows is a relative of vms, an ugly cousin but still family. Its growth is stunted, Windows 7 is the fifth version after W 3.5. VMS grew a lot faster, with more (end user) functionalty, more stability during its first two decades.
Even then Windows 5.1 (aka XP) is stable and useful. Vista wasn't then again VMS 6.1 wasn't that mature either...
Hans
-----Original Message-----
From: <Paul_Koning at Dell.com>
Sender: owner-hecnet at Update.UU.SE
Date: Fri, 10 Aug 2012 14:28:45
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
In my case, gcc with the default makefile. I don't use VC (or the OS it runs on) unless serious force is applied...
paul
On Aug 10, 2012, at 3:02 AM, <hvlems at zonnet.nl>
wrote:
How was simh compiled? I used Visual C and the difference between running the compiler with optimization on or off made quite a difference for the generated code. And gcc might compile even faster codefiles.
Hans
-----Original Message-----
From: Sampsa Laine <sampsa at mac.com>
Sender: owner-hecnet at Update.UU.SE
Date: Thu, 09 Aug 2012 23:07:24
To: <hecnet at Update.UU.SE>
Reply-To: hecnet at Update.UU.SESubject: Re: [HECnet] AXP Emulation
Why is SIMH so slow though?
As far as I can understand, one MIPS is roughly one VUPS, correct?
So how come I get 14 VUPS on the same host running SIMH whilst my Hercules install peaks at 180?
Are the architectures that different (obviously they are) or what is it?
Sampsa
