Intel proposes x86S, a 64-bit only architecture

[Aaronage]

Would love to know your opinions on this proposal

Intel proposes x86S, a 64-bit only architecture - VideoCardz.com

Intel publishes a white paper on x86S, a 64-bit only architecture Intel is paving the way for a transition that removes legacy 32-bit and 16-bit support. Most gamers have probably switched to 64-bit architecture years ago because 32-bit OS didn’t support more than 4GB of memory. Modern...

videocardz.com

Proposed benefits from the article:

Benefits of x64-bit only architecture according to Intel:

• Using the simplified segmentation model of 64-bit for segmentation support for 32-bit applications, matching what modern operating systems already use.
• Removing ring 1 and 2 (which are unused by modern software) and obsolete segmentation features like gates.
• Removing 16-bit addressing support.
• Eliminating support for ring 3 I/O port accesses.
• Eliminating string port I/O, which supported an obsolete CPU-driven I/O model.
• Limiting local interrupt controller (APIC) use to X2APIC and remove legacy 8259 support.
• Removing some unused operating system mode bits.

 

[jbailey]

My opinion is that it is about a decade overdue.

 

[Cmaier]

didnt i propose that 2 years ago?

 

[Yoused]

My opinion is that it is about a decade overdue.

four decades overdue and not that big – the 386 should have been a departure, not a stopgap

 

[throAU]

Don’t care too much what intel does these days.

Yes overdue, but I think most of the talent left and it’s going to be a shit show that nobody will want.

 

[Colstan]

Don’t care too much what intel does these days.

Yes overdue, but I think most of the talent left and it’s going to be a shit show that nobody will want.

I think we've found @Cmaier's doppelgänger.

 

[dada_dave]

Interesting


So less meaningful than at least I supposed?

@Cmaier what’s the privileged 32-bit ISA?

 

[Cmaier]

Interesting


So less meaningful than at least I supposed?

@Cmaier what’s the privileged 32-bit ISA?

I assume he’s referring to instructions that are only allowed to run with CPL = 0. Things like HALT or MOV when used with control registers.

 

[dada_dave]

I assume he’s referring to instructions that are only allowed to run with CPL = 0. Things like HALT or MOV when used with control registers.

So not all 32-bit instructions are getting removed? I remember you saying it was more complicated than ARM’s transition given the relationship between the two, 32 and 64-bit for x64.

 

[Cmaier]

So not all 32-bit instructions are getting removed? I remember you saying it was more complicated than ARM’s transition given the relationship between the two, 32 and 64-bit for x64.

well, i mean, i don’t even know if intel actually intends to build such a thing. I thought it was just a research paper.

In the end, there are lots of useful 32-bit instructions - you seldom need the precision of 64-bit data, and even less seldom need a 64-bit address space, so if they ever did pull out 32-bit instructions it would be the ones that cause the most problems by complicating the design, I’d imagine.

 

[throAU]

I guess by "32 bit removed" they mean the machine boots up in 64 bit mode (long mode? its been a while) rather than 8/16 bit DOS/real mode, but as per above the 32 bit instructions would still exist - you'd need to have at least some of them (e.g., the instructions to move, increment, decrement, IO, etc.) as sometimes you need to work with quantities of data smaller than 32 bits for poking at IO peripherals, etc.

Never mind, as above if you don't need 64 bit quantities of data you can save both space (and possibly processing time) with smaller units.

unless intel intend on breaking most PC peripherals by doing this.

maybe... intel be doing intel things... they did some "no 16 bit mode" processor before to try and flood the embedded market with fire-sale price 386 era (from memory) chips deliberately crippled to not be usable in PCs due to lack of 16 bit mode.

Intel 80376 - Wikipedia

en.wikipedia.org