Loongson 3A6000: A Star Among Chinese CPUs
chipsandcheese.com
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Is the process where cutting off an opponent’s access to a resource causing them to become more powerful a thing?
And now we see that this is rapidly degrading over the last decade.
I think the belief was that if the west cutoff China, they would be left in the dark. Instead they have more than enough knowledge on how to make these things that it became a driving force to active decouple from the west.
Provided the other economic/demographic/political issues don't become a major problem to China, this will definitely be a large blunder.
without tech war, China could progress much faster in emerging tech(AI?). But since there is no counterfactual data, there always will be people who use this to push narrative.
The time to clip China's wings was the late 90s, but we were too drunk on triumphalism and busy looting Russia.
Alexa, show democracy rankings of countries who are sympathetic to China
Except it's even worse than that. It's so easily reduced to parody because it was a strawman to begin with. We don't really give a flying ** about democracy; if that were true, would we have backed the string of strongmen running South Korea in the first 35 years of its independence? Would we ever let a single dime reach Saudi Arabia? I wish our leaders would be honest about it though-- if we just said "we have economic and military hegemony and it's our mission to preserve it", then nobody will waste their efforts trying to find middle ground and win-win solutions.
We should ask why China is winning hearts and minds overseas: maybe they're prioritizing the things people actually need? They don't come in and airdrop a half-baked democracy on a country with little interest in it. They've been loose with the economic aid, and have strayed away from the Western/IMF "let's demand massive austerity and privatization" gameplan. There's nothing stopping the US from doing the same things, but with a bigger bankroll to play with.
Now, could we try some strategic empathy, learn about other people around the world, why they despise us, and maybe try to arrest the collapse of the West?
Or are we ok with just snarky mismanaged decline?
The point is to slow them down and just make it harder to compete today, the US is pouring more money into chip research and manufacturing than the entire rest of the world combined, and nobody thinks the US is going to fall behind anytime soon. Not to mention the 5 other massive strategic disadvantages China has just purely on geography alone (i.e. energy policy).
TL;DR Who cares if China is self sufficient on tech in 10 years, they were gonna be self sufficient in 15 years anyways, and it's not like China is going to be loading up on Nvidia's stack forever.
If there was going to be a time to do it, it would be now. Any later would just not matter as they would be ramping up their own production anyways.
Before USA's trade war, 99% of CN companies, even the state owned firms, believe in 造不如买make your own is not as good as buying. Most purchase decisions is based on market forces, better product, more reputation, competitive priced = deal. Its really hard for Chinese companies in chips, semi equipment, etc to break into the market. Say you want to compete with TI in microcontrollers, nobody wants to buy from you when they have mature products from TI.
Now, the USA with export bans and its own subsidies, single handedly destroyed the "make your own is not as good as buying" mentality. Every company in every sector now has to worry, if I buy a microcontroller from TI for my toaster, what if Washington have a mental break down tomorrow and decide to ban it with a stroke of pen. Even if my alternative isn't as good, I won't have a business. And as companies starting using alternatives, that product gets better with feedback loop and iteration. Rome isn't build in a day, but it's built by human hands. Once a product starts the commercial cycle, it improves. People believed that US sanctions only targets selected companies, then Oct 2023 GPU ban targets the entire country, every single company. Now even a game streaming company can't buy the GPU they want. What do you think companies with 10B dollars of revenue streaming video games are going to do? Invest in every single semi-conductor companies in the entire supply chain, from GPU, to EDA, to semi-tools. USA is attacking huge sectors of CN economy, sectors with revenues of hundreds of billions of dollars, making an enemy out of all them, what do you think they will respond? The demand is still there, people will still buy their toaster, watch livestreamed video games, companies will need to operate, and the supplies are needed. Whoever can fill that demand laughs to the bank.
The trade blockade strategy might work for smaller countries. But 1) China has always been many forms of trade blockade ever since the country is founded. See wassenaar arrangement. China can't get advanced machine tools, EDA, CAD, and many others. So there are many small companies, research labs, SOEs, universities that have been doing R&D on these tech for decades. The problem is products in these areas have very strong winner takes all effect, they don't have marketplace battle tested products. But the flip side is that they have talents, they have some IP, know how and tech. Chinese semi tools companies are rapidly advancing in the last 6 years, but they started 20 years ago because the west's sanctions on China. So when US wages the tech blockade, Chinese don't start from scratch, they take what they have in the lab, not mature, but have some value, and start putting it on production lines and iterate. 2) CN has a large internal market, and increasingly competitive in global markets for all kinds of goods, even if the entire western world stops buying from China, the rest of world + internal market is big enough for many products to be profitable and iterate. As long as there is demand, there will be people study and making it. 3) CN has surplus of university grads, many universities, etc, what if we find them some work to do?
Oh and the reason why CN has been doing self-sufficiency is because the country has always been sanctioned since its founding. And western decades of western sanctions have created CN's R&D industrial base in "hard tech", such as materials, automation, industrial software, optronics etc. I guess many policy experts forgot this fact and never bothered to study what really goes on in China. They forgot they have been sanctioning CN for decades and the Chinese have always thought they can't rely on others. Why do you think they can trust you when you sanction and attack them? The self-reliance mentality is created by western sanctions. The solution is always build trust and remove the rational that causes others to think a certain way.
1. Stopping technology transfer worked exceedingly well for the west weakening the Soviet Union during the Cold War.
2. A distinct lack of (non-violent) alternatives for the West preventing China becoming the world's leading technological superpower (and hence also strongest military).
I doubt this will be successful in the long run, because China is not burdened by the Soviet Union's extremely inefficient way of organising its economy. Not to mention that China is the worlds biggest market.
I'm pretty sure we're rapidly heading into a West vs China military conflict. I think part of the reason we've held rates higher for longer is that it hurts China more than the West as a way to undermine the Chinese economy. Coupled with the sanctions the West is getting ready for a 'timing attack'. But if the West is wrong and loses that war then we're effed. I would prefer a graceful stepping down from world hegemon and taking our seat at a multipolar world where we can focus on getting our own house in order. But obviously those in charge have other incentives.
All that’s needed is a military containment of China.
Are China's demographics appreciatively different from other industrialised countries? Questionable. Not to mention that it's unclear why an aging society is a problem at least for the next 100 years or so (e.g. most violent crime is perpetrated by the under-30s). It's also easy, at least for a dictatorship, to increase the birth rate (e.g. restrict access to all birth control, give massive preferences to families with children, like housing, salary, "bachelor tax" etc).
> military containment of China.
That is expensive. One frequently cited explanation for the collapse of the Soviet Union was that its poor economy could not support its oversized army, which it needed to keep the Soviet Bloc at heel (not to mention all the revolutions and secession movements it fostered elsewhere).
Also, does anyone actually believe that China is expansionist? Compare:
https://en.wikipedia.org/wiki/List_of_wars_involving_the_Uni...
https://en.wikipedia.org/wiki/List_of_wars_involving_the_Peo...
The strategic problem of China's rise is more that other countries will eventually switch allegiance away from the West.
Yes. Also, it is very likely that China has been covering up the true extent of the demographic problems. And not necessarily to hide it from its geopolitical rivals, but to hide it from its own leadership fearing purges and punishment. Like ... there's a 100 million people "missing".
"it's also easy, at least for a dictatorship, to increase the birth rate"
No it's not, because those changes take a while to implement, and even if the birth rate skyrockets, you don't get usable workers for 20 years.
Plus, China's economy is urbanized, and its economy is built around cheap labor that is worked to the bone (996). To make urban areas viable for raising kids, you need to decrease hours worked and increase wages.
And, people need to feel optimistic about the world and the future.
So lets say a massive sweeping change was implemented to make having children quite a bit more appealing. It would probably take about 5-10 years for the policy changes to trickle through the various layers of state control (China is kind of feudal in nature), monetary incentives will likely be greatly reduced by corruption.
Then 20 years later, you start to get a blip upward. Because the issue is, the people that will have the kids are ALREADY THE SMALLEST GENERATION EVER from one child policy. So to move the needle, they need to have ... like ... 8 kids each.
One child policy forced families to pick a gender as well. You won't believe this, but culturally people preferred boys. So the smallest generation ever, which would be 50-50ish, is more like 40-60 or 45-55 (maybe not that stark, but ... kinda is) then ... well, your expansion is limited by the wombs.
https://zeihan.com/new-chinese-demographic-data-population-c...
So, keep in mind Zeihan is a bit of a clickbait artist. He sells himself and makes bold claims. But if he is right about those new vs old/fake numbers, that is some bad stuff.
The solution to falling birth rates is immigration. And while China does see a lot of immigration, it does have a large rural/urban divide, so it might be able to "immigrate" people from the rural classes (who as I understand it are currently treated as a lower class of people).
The only ones to switch allegiance to China will be the ones who have been bought off.
I’m also confident that the Philippines will now claim that China is the worst offender in the South China Sea.
As for any country involved in the 9 point line including Malaysia, anyone would have to be delusional to think that they support China stealing their territory
Just face it, Xi is steering China towards another big leap backwards. All the foreign provocation is distracting from serious domestic issues.
Malaysia and Indonesia responded to AUKUS with alarm, do you deny this?
Let's say that even this reading is heavily disputed. I don't think the Director of the Global South Program at the Quincy Institute, and member of the adjunct faculty at George Washington University, is as "delusional" as you think. https://responsiblestatecraft.org/biden-vietnam/
Countries like China are unable to take advantage of immigration. If increasing birth rates were easy for authoritarian countries like China, they wouldn’t be in this mess in the 1st place. This is a terrible argument. This situation is made worse with many mainlanders are trying to leave China.
The US and its allies like Japan and Australia have already implemented containment of China in the island chains. Pretty sure that thr Philippines and Vietnam are on board as well. This wouldn’t have happened if Wolf Warrior diplomacy weren’t a thing. All anyone has to do is cut off imports from the Middle East to cripple China. (No, Russian imports aren't enough. Most of their pipelines were destined for the EU. )Even India can cut off Middle East energy exports on its own because China doesn’t have a long range navy.
The BRICS coalition has also largely been a failure because no one can agree on what currency to use.
If either the Hu or Jiang faction were still in power, none of this would have happened because unlike Xi neither faction was delusional.
2. Iran isn’t doing anything but proxy wars here and there. Mostly in places where we will eventually retreat from.
3. Washington doesn’t need to contain any of them. Globalism is no longer a US interest. We are tired of subsidizing world trade and world security for little to no gain. All we get plenty of is criticism. Only countries that need energy imports from the Middle East are worried about the Houthis. Unlike many other countries, the US does not need energy imports or food imports. This is everyone else’s problem now.
2. I guess this is a way to dodge the Houthis question, who are actively striking US-aligned ships. What happened to "Operation Prosperity Guardian"?
3. And yet Washington does want to contain China? This sounds like "I can't lose because I'm not even trying".
I know the 'demographics is destiny' is the Washington Consensus but it should be understood that these are the same people wrecking our economy over and over again and starting forever wars we end up losing.
- China is facing a massive demographic bomb from one child policy
- China is a financial house of cards. Some of the stuff I've read about is 3 billion apartments built as investments/savings which are actually worthless, local/state debt and shell games that is frighteningly leveraged, and the general cheap/empty consumption/construction that state driven funding has produced
- China is turning sharply authoritarian, possibly headed to Stalinist levels of purges and cult of personality with Xi.
- China can feed its population and gets its oil due to free trade and shipping, quite extended supply lines, which are going to get a lot more chaotic in the future. If/when China attempts to invade Taiwan, the US will impose a naval blockade on its shipping (Zeihan claims a "couple destroyers in the Indian Ocean" ... probably a BIT more involved than that) ... China will starve and its economy will stop functioning.
I think this is part of a multipronged trade war to attempt to collapse the Chinese Communist party. If you want to talk about "powers that be", consider what is on the table here: the Putin regime will likely collapse from the failures in Ukraine, and Russia (who is facing a demographic bomb almost as bad as China's) is expending its last functional generation of youth on human waves in Ukraine.
So the two major nuclear powers might collapse entirely, and the only real economic rival to the US.
But part of that is just the state of economics in the realm of mass media.
To that. Economist - Definition : Someone who can tell you today why yesterdays prediction of tomorrow was wrong.
Q. What do you call an Economist that makes a prediction? A. Wrong.
Other point of consideration is sometimes things breaks with a whimper not a collapse. Real estate technically "broke" with 3RL = expected 2-3% drop in excess / unproductive GDP. Collapsist think PRC will turn into Yemen without pumped up RE growth, but actual RE sales is ~15% of economy, the often quoted ~30% number includes ancillary industries like construction that got redirected to other projects like renewable rollouts. PRC RE sales dropping from 15T (yuan/rmb) in 2021 to 12T in 2023 out of 100T GDP = today's "quality" growth at ~5% instead of previous wreckeless growth ~8%. Meanwhile, resources directed at actually useful strategic industries, backed by pipeline that generates about as much high skilled workers as western block combined doing actual useful things like building EVs, fabs and generally moving up value chain. IMO west is going to miss the days PRC wreckeless sunk money in real estate instead of high tech products that will directly challenge encumbant western market leaders.
- no one seems to be contradicting the contention that the CCP under Xi has become sharply authoritarian, regressive, and is worsening
- the reported demographics may be sharply worse for the immediate forthcoming generations than previously reported: 100-250 million "missing" people, and a sharply worse male-female ration that previously reported. Again, for me, these depend on the size of the Chinese rural population, which I think might buffer demographic declines in urban areas.
- the financial "bombs" I agree are the least significant ones in terms of dramatic collapse scenarios. They are the ones all the rich care about because they might lose money, but the Chinese can print money and impose price controls and lots of other things that Western economies probably can't get away with.
What the financial numbers mean is two symptomatic signs: degree of corruption in the system but, worse than corruption, the degree of incompetence of the CCP to properly centrally manage things as they consolidate authoritarian control.
You won't find me defending economics on fundamental principles. Economists basically exist to justify the status quo power structure and are utterly incapable of constructing models to include things to price environmental degradation that might, you know, destroy human civilization.
I think that if China had not turned sharply authoritarian, they would be fine. It is a modernizing country of 1.4 billion people. But not the double-combo
The market will stay irrational far longer than anyone anticipates. But eventually, we the fundamentals correct the whole thing.
China will not face starvation because it shares a land border with Russia, which has enough food to supply China if necessary. However, this scenario is unlikely to unfold, as it overestimates the power of the US in this conflict. The conflict would predominantly be a naval battle, with US forces engaging with what are essentially forts. Most war games conducted in the US indicate that in an initial battle, the US would be defeated and forced to retreat. You should read the report presented to Congress a few months ago about China's military capabilities.
> the Putin regime will likely collapse from the failures in Ukraine
Based on situation today, lets just hope that Ukraine will not collapse because we are very far from Russia collapsing. See IMF data about their economy and situation on the front.
India might also become opportunistic and start to resolve its boundary disputes with China.
This also doesn’t account for Xi’s purges of the PLA including its all important rocket force.
It is doubtful what can be essentially considered a single fragile rail route can provide it logistically.
the Russian yields are not fantastic, and atop that Ukraine is for the foreseeable future not available for providing grain.
A war with China will disrupt international trade so much that grain demand will explode (countries will probably stockpile more) and the grain providers can select 1) blockaded china or 2) any of a hundred other customers.
https://chinapower.csis.org/china-food-security/
So Brazil, Argentina would be out, can't ship to China
US would obviously stop exports
Canada, Australia, New Zealand, France: out
Indonesia, Thailand: probably out.
I agree that Russia is not in a situation of imminent collapse, neither is Putin in danger of imminent overthrow. However, demographically the Russians are expending the last of their skilled and young workers, while forcing Europe to no longer need their oil + gas, accelerate all EV / PV / Wind initiatives. Russia will lose "the last decade" of high oil profits before the demand begins to collapse.
Russia has also emboldened its other satellite conquests with its military incompetence. There was a video of Putin negotiating publicly with one of the southern states (don't remember, may have been Georgia) where the leader at the public negotiation table outright defied Putin. Meanwhile Ukraine modernizes, trains, becomes stronger and more effective. NATO is arming, and at this point Ukraine will probably be the site of an actual NATO-Russia conventional battle, which given NATO's ability for total air superiority means a complete defeat. If you're wondering who would fight the ground war given likely American apathy for another war, Poland would ENTHUSIASTICALLY fully mobilize to fight the Russians.
Down the line, Belarus's propped up government will fall, and Russia is staring at virtually a multi thousand mile border with outright NATO or might-as-well-be-NATO countries between Finland, Baltic republics, and Ukraine, and probably Belarus as I just said.
Black Sea access is very tenuous. Kalingrad is unreachable, and may secede. North Sea access is really tenuous.
Honestly the only hope for Russia is Europe doesn't arm fast enough and the US House of Reps holds up funding (which I believe 96bln just got approved).
And Russia's leadership is historically aware, what is happening as a result of this war (severing of gas supply dependence) is an armed Germany. The prospect of a fully industrially armed and modernized German military should strike a deep cultural fear in the entire Russian people.
And we didn't address the oil/petroleum issue. China can stockpile what they can, but an embargo will still result in the lights going off in China within 30 days.
China is still essentially a warlord state, and Xi is likely generating substantial resentment in the regional power centers. If the central government fails in a blockade, the Chinese state, fragmented between the free market liberal urban governments who resent the free market rollbacks, the CCP power center, and who knows in the rural areas, will crumble into warlord states.
As a side note, not a lot of people talk about the SOuth Korean demographic bomb (worst in the world), but if China falters the solution to South Korean demographics is to topple the North Koreans and import their population into the South Korean economy. I think that will happen in the next 20 years.
The literal only reason I see is jealousy. Power tripping.
The whole weapons thing is bullshit. You don't need the top of the line ic to power military equipment. This is really just petty jealousy and economic hording by the USA.
In a street interview in China (Xinjiang, even) about sanctions, an old man gave an interesting answer. He did not express resentment for the sanctions. Instead, he said: let them sanction, in the end we can't rely on others for our own prosperity and development.
He is right. There is no point in Chinese resenting the sanctions. There is no point in foreigners criticizing the sanctions, we all know it's no use. The only thing that matters now is for Chinese to focus on work. Focus on our own R&D. No need to say much, just get things done.
This is not about China resenting the sanctions. You already have the right attitude This is about a US citizen looking at the US and feeling ashamed at our own virtues.
We should share technology and work together. Not fear one nation surpassing the other.
I have a Uyghur acquaintance in Germany who's pretty mad at the media's depiction of stuff. He views it as slander of his home region. At the same time he resents that most westerners don't actually care about the truth, they just want their viewpoints confirmed and get mad at him for presenting a different narrative.
He even gets death threats from other Uyghur diaspora for holding this view.
All street interviews that are shown in media parrot official state talking points. If you don't understand that, I don't know what to tell you.
I think it's actually a shame that you now live in a society with free access to information but choose to take state media at face value.
I think the idea is to starve the Chinese on AI advances, but there isn't much point spending a fortune training such models when you can have an insider leak it to you for much less money.
But why is this a good idea? You're saying it as if it's obviously a good idea. Why not cut off the entire food supply from some impoverished nation in Africa? Is that justified? What justifies stopping AI advances or blocking technological progress in China?
Seems like the main justification is that we can't accept China surpassing us. That's not a moral excuse, it's a petty one.
So, it's to our advantage to give away IP instead of making them discover and invent things on their own? This is some r/latestagecapitalism level of nonsense.
I said I think we'll lose and even if we win the result will still be calamitous. I think people have rose tinted glasses of the 1950s and think that a war time economy and a military victory will bring that back. It wont.
The western technology companies will be somewhere way way farther along/bigger by then - look at spacex flight this week for comparison at how fast western technologies move.
> How a Big U.S. Chip Maker Gave China the ‘Keys to the Kingdom’
> Advanced Micro Devices revived its fortunes through the deal, and sparked a national-security battle
https://www.wsj.com/articles/u-s-tried-to-stop-china-acquiri...
IIRC that company is called Zhaoxin, which has had mild success getting ~Zen 2 performance domestically.
I'm not to sure why WSJ is citing that as a 'national security issue', everything related to China seems to be called that now.
Yes, there are some different key details but the parallels on the messaging is neat to see.
What kills it for the home and small business use is that it's MIPS. Just not worth saving 50 or so dollars of AMD / Intel premium for this trouble. As I understand, this CPU doesn't have an iGPU which makes it an even worse deal.
Otherwise agree though, they're unlikely to go international at this point!
Windows is clearly never going to be ported to this oddball MIPS architecture so their stack will all be dependence on open source but sadly they will not return the favor by releasing their source or maybe my perception of China open source is biased.
That's not quite true and your bias is showing. The company behind Loongarch is reasonably friendly to FOSS and most of their LA64 changes (to Linux, llvm, binutils, gcc, etc) are upstreamed in a timely fashion. As for the chipset, kernel drivers are all open source although not all have been accepted upstream. I have personally been maintaining the out-of-tree Linux drm driver for their onboard gpu chip and it's available on github https://github.com/cl91/linux/tree/gsgpu-devel. If you have a barebone 3A6000+7A2000 setup, as far as I know the only closed source component needed is their userspace mesa driver for the onboard gpu.
No ISA spec has been published. A few research articles are available from Chinese universities but most are only available in Chinese.
FWIW The Chinese government seems to be trying to encourage open source, they even run their own equivalent of github called gitee. https://gitee.com/explore
A lot depends on the cost to produce that chip, whether Loongson can scale below 14-12nm they’re using currently (EUV without ASML?), and what development resources Loongson can deploy for their next microarchitecture revisions, which aren’t discussed here.
Which is fine. For most applications, it's the order of magnitude of performance that matters. Not +10..30% or say, Zen 3 vs. Zen 2 (although gamers & AMD/Intel execs will argue otherwise).
Machines with >10y old cpu's are still perfectly useable for (most) everyday tasks, as long as the software support is there. Especially when coupled with enough RAM, decent gpu, SSD etc.
On the way from "pointless museum piece" to "latest & greatest", this cpu is 9/10s there.
Finally a sound voice in this merry go round of one-upping. Totally agree. The funny thing is, if people paid half as much attention to optimizing the bloat crap they build, instead of drooling over 10% cpu gains, you’d see a much bigger improvements. Obviously it depends on the domain, but everything I’ve come across (except core tech like SQLite etc) have huge overhead in both memory and cpu that could easily be optimized if someone paid attention.
Like the json parsing issue with gta online, that’s a perfect yet egregious example of software practices today.
64 is _very expensive_.
In terms of design, China has world class companies. However in terms of fabrication and especially semiconductor manufacturing equipment, they are still somewhat behind.
Also x86 is very sticky - it is going to take them a decade to get rid of that.
And not just companies. This is currently the world's top open-source RISC-V development https://github.com/OpenXiangShan coming from the Chinese Academy of Science.
(Whether China will remain investing in RISC-V, given that the US government has started to pressure US RISC-V development to limit their involvement with China is another question.)
It is very much like the last revision of MIPS but modernised a bit: No more branch delay slot. No HI/LO registers. The arithmetic ops that trapped on overflow are also gone.
There are published docs only for the scalar ISA subset: https://loongson.github.io/LoongArch-Documentation/README-EN...
Chips and Cheese has an analysis of the "LSX" and "LASX" SIMD sets. LSX is very much like MIPS's MSA. LASX is extended to 256 bits: https://chipsandcheese.com/2023/02/26/loongsons-lsx-and-lasx...
I would understand if that would be for legacy support, like x86_64 decoded to risc-v.
LoongSon does however supposedly have a instruction set extension for running binary-translated x86 code faster (and ARM and RISC-V), but they have not published much about it.
All that to run binary distributed x86 apps...
However, designing a CPU takes years. Back when they transitioned from MIPS to LoongArch, RISC-V wasn't mature enough to have all the functionality that their MIPS cores did. There was no ratified Bitmanip extension and it was unclear what kind of vector extension that it would get.
How so?
It was released almost two years before the first rvv 1.0 hardware became available at the end of last year. Without out it, we wouldn't have had any hardware at all.
rvv 1.0 has quite good upstream compiler support already, and before that the t-head had custom compilers that supported their rvv 0.7.1 version of the vector extension.
Now upstream gcc supports it as an alternative codegen target as well, so you can write rvv 1.0 vector instrinsics and compile those to the thead rvv 0.7.1 implementation.
I'm not aware of any company that plans to release a non rvv 1.0 rvv implementation.
Arm/x86 fan boys?
T-HEAD [1], Ventana's ternary op [2], Sifive also has a couple [3], including "Xsfvfwmaccqqq", one of at least four completely different matmul variants.
In particular for the latter, I would say fragmentation is an absolutely valid concern at the moment.
[1]: https://github.com/T-head-Semi/thead-extension-spec [2]: https://github.com/ventanamicro/ventana-custom-extensions/re... [3]: https://www.sifive.com/documentation
The vendors presented their own matmul extensions, but none of them solve all problems that the integrated matrix extension should solve. Most importantly binary compatibility across vector lengths. The last to meeting presented alternatives that would satisfy that requirement. It will however take some time to decide on and experiment with the best design.
I agree that this can turn out messy, so far I haven't seen anyone, outside of vendor libraries, use the t-head or SiFive matmul extensions in open source code.
Ventanas ternary op and similar will hopefuly consolidate on the cmov extension.
(there are still people thinking there will be no tradeoff).
cmov extension? Like on x86?
The real signficant and annoying fragmentation is 32/64 bits (accutely painful on x86).
Perhaps embedded systems engineers see things differently if they know exactly what CPU they are going to target.
32/64 bits? It's been years since we dropped support for 32-bit x86 :)