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This makes no sense to me

If I think about asm:

function1:

    (do stuff)

    jp function1

    ret

function2:

    (other stuff)

    ret

main:

    call function1

    call function2

the 2nd call might happen internally due to branch prediction but in practice it shouldn't and the processor fixes this

Oh yeah and TFA also goes with:

> The funny bit is that C got this right.(...) but C included one more rule: loops whose controlling expression is a constant expression may not be assumed to terminate.

Well, duh! A broken clock is right twice a day it seems


With UB the compiler has no particular requirement to emit the 'ret'. (or, in the example, anything at all for the function)

They do

x86 bytecode is bytecode


I mean don't modern CPUs basically just run an x86_64 emulator on a RISC machine anyway? Like there's a layer between the microcode and the actual x86 instructions already.

No, they don't. x86 is a superscalar processor, and it does what all superscalar processors do--translate the instructions into µops for execution and dispatch to the various execution units, with the µops not being 1-1 with the original instructions. However, it was supposed to be impossible for a CISC architecture to be superscalar, so this is what spawns the myth that it's somehow cheating by executing a RISC architecture under the hood.

Thanks, I didn't know that and now I do.

Reality is very different.

The fact that x86 is not RISC, it contains many instructions which support memory as the source and destination or both, something which is often an advantage in terms of code density, and speed.


Yes, but the “architecture-independent” bytecode for these RISC machines that run underneath your various Intel and AMD CPU models is the x86_64 instruction set.

No, that's a myth. It's true that the instruction decoder in a CPU core translates from ISA opcodes to micro-ops for the backend, but those micro-ops are in many cases functionally very close to the ISA instruction and decidedly not RISC-like. For example, the ADD r/m64, imm32 instruction (read from memory, add constant, write to memory) is translated to a single micro-op on several Zen architectures [1], which is far from anything you could call "RISC".

[1] https://uops.info/html-instr/ADD_M64_I32.html


I think it's more like a (kinda) VLIW machine but yes, pretty much

VLIW implies packets of different independent instructions that can be executed in parallel. I dont think this definition is ever true for the vast majority of x86 instructions.

that bites

Yeah, works if you're 2h away from the venue.

Im away 6h from the venue and 3h from my family.

Come on...


> That marketing guy should not be talking to the press, as he does not have the skills

They have way more skills than the technical folk in doing that


If I had been just out of Uni I would think this is edgy

Now I'm just glad I'm not responsible for this fire


Funny, to justify Brexit numbers like these were meaningless

Putler invested a lot in that. Cheap price for the impact we still see.

No, it seems governments can only ignore the concerns then complain the 'alt-right' parties get voted

...or blame russia!

(Some media literally blamed putin because people voted for afd in the recent state election in germany).


What would you have a troll army promote besides AfD narrative if your objective is to fuck with short-term well-being?

AfD is a result of people wanting something and the government doing the opposite... this means that people are looking for an Alternative (intentionally capitalized here).

People just want a nice cozy job, enough money to get an apartment/house, buy the basics they need and live in a safe environment. If you provide those, no one is looking for alternatives.... when one of your bigger companies announces letting go of 100k people in the next few years, when you need concrete blocks protecting your chistmas markets, when you're deciding between eating and paying for diesel for your car to get to work, then you're looking for Alternatives.


Check out what the party actually plans. It's the exact opposite of what those people that vote for it need. The demographic is based on uninformedness, correlating with lower incomes, marketed towards the group that feels disadvantaged because they feel that others around them have it better. This party is not going to advantage anyone, high or low income, but a step down in welfare hurts the most if you're already low income so best not choose them in that case.

If you want "enough money to get an apartment/house, buy the basics they need", egalitarian Linke is the obvious choice, and the "and live in a safe environment" part is something literally everyone wants, hard to make a wrong choice there (though with their support for Russia, maybe AfD is questionable even on that front)

> when one of your bigger companies announces letting go of 100k people in the next few years

...then you need social welfare the most? Linke is the biggest proponent of that. What is the logic here?

> a result of people wanting something and the government doing the opposite

This is perhaps the most mind-blowing part. For decades, the right wing government with Merkle at the head did very little for long-term good, so what's the opposite of that? Move further right!! This time it'll work for sure! Blame all the foreigners, inside and outside. Kick them out, reduce international collaboration and trade, and for a cherry on top, fuck the global climate even more than the compromise position previous governments were already pursuing. That'll fix all future problems

No, obviously the opposite of leaving it all to the market and having strict immigration is to nationalize the things people actually need (as you say, things like housing) and have no concept of asylum (anyone can walk in and work here). Will that solve it? Maybe we need some middle ground? I'm not sure anyone has definitive answers to make a perfect world, but this nazi party is so far out there, saying it is "just an alternative" is like saying hitler was "just an option" that we could try and see how it works out. Yeah, people want something 'different' but what level of stupidity do you need to expect that voting for nazis is going to make things 'different and better' instead of 'different and worse'?


It's not a "bunch of teenagers", a regular pipe won't cause a train to derail, one would need heavy machinery to move that rail in France

Nothing was derailed, they put pipes on the rails that tricked the system into believing there was a train on the track, shutting it down

There are two sabotage acts being discussed; a train was derailed in the other one.

Enjoy and consume $product faster

Thanks for buying $product, $consumer


Yes. Because 3 points are coplanar, so every "3D problem" with 3 objects can be turned into a 2D problem on the correspondent plane

(of course in real life your plane would keep changing, and probably some other complicated math I can't think right now)


Put another way, while their positions are one set of 3 points, their momenta are another set of 3 points, and there is no requirement that 6 points will always lay on the same plane.

I wonder what phantom forces would appear when the reference frame changes in some complicated fashion. We get centrifugal "force" when we reconstruct F=dP/dt in a rotating reference frame, what would the 3-body "force" look like?


Oh makes perfect sense, do you have thoughts about real life examples? I did some research using AI and it said there were examples of restricted 3 body problems like the trojan asteroids, but no examples in real life similar to what is in this web app

Why would the plane keep changing? If there are only these three objects, won't the vectors of their gravitational pull to each other all be on this plane too?

If you define the initial conditions such that their relative velocity is zero or parallel to the plane, yes. But that's not the case in general.

Not from an external point of view, as you might have a momentum component perpendicular to that plane

(but yes I think you might be right if we're centered on the CG)


One of the necessary conditions here is that the three objects return to their exact initial position, and so does the centre of mass. Initial conditions with non-zero momentum must trivially be ruled out. But this doesn't stop them from having velocities perpendicular to the initial plane that cancel out perfectly, so this doesn't refute the assertion that the planes keep changing.

Sorry, but this is a word salad.

Most of the solutions always have non-zero momentum, including in the initial conditions. And https://numericaltank.sjtu.edu.cn/three-body/three-body.htm includes periodic solutions that move in all three dimensions.


They presumably meant non-zero total momentum. If the total momentum were non-zero, then the center of mass will be moving in a straight line, and will not return to where it began, and therefore the orbit would not be periodic.

Big picture the center of mass momentum is concerned and it does not matter if the system as a whole is moving up or down or to the right or the left. Like the Earth is basically orbiting the sun in an ellipse [1] so far as the sun is concerned and from the viewpoint of the solar system not care so much that it is moving around the galaxy unless we are interested that orbit being perturbed by other stars that we pass near over millions and milions of years.

[1] ignoring the parameters of that ellipse changing slightly and slowly thanks to the other planets


Oh. That makes sense. Yes. The total momentum has to be zero.

All of the things in the solution can constantly have momentum.


Oh sorry, yeah - I wasn't fully awake yet when I wrote it. As a sibling comment mentioned, I was talking about the total momentum. Anyway, it was in response to GP's assertion that GGP may be correct if "we're centered on the CG", which doesn't make sense because the CG can't move.

Each orbit is a spinning top. You pull on a top from the side, it's spin axis precesses.

It’s an arbitrary plane, chosen at each moment just so you can flatten it

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