Comment by ksec

There are software compiled today without using MMX support. I was thinking the idea of something that is open or for licensing is an 86 ISA that is forward compatible. And for customers that requires strict backward compatibility they could still source it from AMD and Intel.

i.e Software compiled for 86 should work on x86. The value for backward compatibility is kept with both Intel and AMD. If the market wants something in between they now have an option.

I know this isn't a sexy idea because HN or most tech people like something shiny and new. But I have always like the idea of extracting value from the "old and tried" solutions.

Software or microcode emulation works pretty well.

So it would be faster and more efficient when sticking to the new subset and Nx slower then using the emulation path.

AFAIK, most of event x86_64 patents are largely expired, or will be within the next 6 years. That said, efforts for a more open platform are probably more likely to be centered around risc or another arm alternative than x86... While I could see a standardization of x86 compatible shortcuts for use with emulation platforms on arm/risc processors. Transmeta was an idea too far ahead of its time.

I don't think it works that way in practice.

Some distributions like Debian or Fedora will make newer features (such as AVX/VEX) mandatory only after the patents expire, if ever. So a new entrant could implement the original x86-64 ISA (maybe with some obvious extensions like 128-bit atomics) in that time frame and preempt the patent-based lockout due to ISA evolution. If there was a viable AMD/Intel alternative that only implements the baseline ISA, those distributions would never switch away from it.

It's just not easy to build high-performance CPUs, regardless of ISA.

The "s" stands for "stupid".

But it's fortunate that they realised the main attraction to x86 is backwards-compatibility, so attempting to do away with that will lead to even less marketshare.

Wut?

>AMD and Intel Celebrate First Anniversary of x86 Ecosystem Advisory Group Driving the Future of x86 Computing

Oct 13, 2025

Standardizing x86 features

Key technical milestones, include:

    FRED (Flexible Return and Event Delivery): Finalized as a standard feature, FRED introduces a modernized interrupt model designed to reduce latency and improve system software reliability.

    AVX10: Established as the next-generation vector and general-purpose instruction set extension, AVX10 boosts throughput while ensuring portability across client, workstation, and server CPUs.

    ChkTag: x86 Memory Tagging: To combat longstanding memory safety vulnerabilities such as buffer overflows and use-after-free errors, the EAG introduced ChkTag, a unified memory tagging specification. ChkTag adds hardware instructions to detect violations, helping secure applications1, operating systems, hypervisors, and firmware. With compiler and tooling support, developers gain fine-grained control without compromising performance. Notably, ChkTag-enabled software remains compatible with processors lacking hardware support, simplifying deployment and complementing existing security features like shadow stack and confidential computing. The full ChkTag specification is expected later this year – and for further feature details, please visit the ChkTag Blog.

    ACE (Advanced Matrix Extensions for Matrix Multiplication): Accepted and implemented across the stack, ACE standardizes matrix multiplication capabilities, enabling seamless developer experiences across devices ranging from laptops to data center servers.

In which space? Desktop and high performance servers? Why would it?

Mature gallery of software to be ported from TSO to weak memory model is a soft moat. So is avx/simd mature dominance vs neon/sve. x86/64 is a duopoly and a stable target vs fragmented landscape of ARM. ARM's whole spiel is performance per watt, scale out type of thing vs scale up. In that sense the market has kind of already moved. With ARM if you start pushing for sustained high throughput, high performance, 5Ghz+ envelope, all the advantages are gone in favor of x86 so far.

What might be interesting is if let's say AMD adds an ARM frontend decoder to Zen. In one of Jim Keller's interviews that was shared here, he said it wouldn't be that big of a deal to make such a CPU for it to be an ARM decoding one. That'd be interesting to see.

Well, given some of the political/legal gamesmanship over the company itself the past few years, it could very well self destruct in favor of RISC-V or something else entirely in the next decade, who knows.

Look how long SPARC, z/Architecture, PowerPC etc have kept going even after they lost their strong positions on the market (a development which is nowhere in sight for x86), and they had a tiny fraction of the inertia of x86 softare base.

Obliterating x86 in that time would take quite a lot more than what the ARM trajectory is now. It's had 40 years to try by now and the technical advantage window (power efficieny advantage) has closed.

It seems to me that interest in AArch64 for on-promise general-purpose compute workloads has largely waned. Are Dell/HPE/Lenovo currently selling AArch64 servers? Maybe there is a rack-mounted Nvidia DGX variant, but that's more focused on GPU compute for sure.

>Does anyone seriously think ARM isn't going to obliterate x86 in the next 10-20 years?

Lunar Lake shows that x86 is capable of getting that energy efficiency

Panther Lake that will be released in around 30 days is expected to show significant improvement over Lunar Lake

So... why switch to ARM if you will get similar perf/energy eff?

20 years is half of x86's lifetime and less than half of the lifetime of home computing as we know it.

So this is kind of a useless question, because in such a timespan anything can happen. 20 years ago computers had somewhere around 512MB of RAM and a single core and had a CRT on desk.

Why would the market jump from one proprietary ISA to another proprietary ISA?