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Apple facing huge chip patent bill after losing case

bbc.com

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Re: Apple facing huge chip patent bill after losing case

#11

Post by throwawaykf05 »

trengrj wrote: post #4
ctz wrote: post #3

Patent in question: http://www.google.co.uk/patents/US5781752

"Table based data speculation" - so a lookup table?? Would be interested in knowing how innovative the patent is from someone with more knowledge in this field.

The first (and often only) thing to read is the claims. Claim 1 for example:

1. In a processor capable of executing program instructions in an execution order differing from their program order, the processor further having a data speculation circuit for detecting data dependence between instructions and detecting a mis-speculation where a data consuming instruction dependent for its data on a data producing instruction of earlier program order, is in fact executed before the data producing instruction, a data speculation decision circuit comprising:

a) a predictor receiving a mis-speculation indication from the data speculation circuit to produce a prediction associated with the particular data consuming instruction and based on the mis-speculation indication; and

b) a prediction threshold detector preventing data speculation for instructions having a prediction within a predetermined range.

Re: Apple facing huge chip patent bill after losing case

#13

Post by masklinn »

timthorn wrote: post #10
trengrj wrote: post #4

Earlier quoted context omitted.

"Table based data speculation" - so a lookup table?? Would be interested in knowing how innovative the patent is from someone with more knowledge in this field.

Bear in mind the patent was filed in 1996 when considering the level of innovation.

There were branch-predicting mainframes back in the 80s, though it really came to the fore with the advent of superscalar microprocessors in the early 90s (MIPS R8000 and DEC Alpha 21064), what is the paper's innovations above these?

Re: Apple facing huge chip patent bill after losing case

#14

Post by bshimmin »

brownegg wrote: post #5
abluecloud wrote: post #2

$862m isn't that huge in the grand scheme of things. Not to mention, it's most likely not going to be $862m, my guess is it'll be less.

If it's $862m, last I checked, it will take them about 30 hours to bring in the necessary revenue--if they want to pay out of profits (I'm totally guessing here, what are real net margins on their hardware? 15-20%?), it'll take a couple days.

Man, that's such a humbling stat. Many of us here don't even earn that in a year!

Re: Apple facing huge chip patent bill after losing case

#15

Post by maxerickson »

brownegg wrote: post #5
abluecloud wrote: post #2

$862m isn't that huge in the grand scheme of things. Not to mention, it's most likely not going to be $862m, my guess is it'll be less.

If it's $862m, last I checked, it will take them about 30 hours to bring in the necessary revenue--if they want to pay out of profits (I'm totally guessing here, what are real net margins on their hardware? 15-20%?), it'll take a couple days.

It would take ~8 days of net income (they declared $10 billion of net income in the most recently reported quarter).

Re: Apple facing huge chip patent bill after losing case

#16

Post by weland »

trengrj wrote: post #4
ctz wrote: post #3

Patent in question: http://www.google.co.uk/patents/US5781752

"Table based data speculation" - so a lookup table?? Would be interested in knowing how innovative the patent is from someone with more knowledge in this field.

Not really, although the technique employs a look-up table. The basic idea is that they found that many instruction sequences that cause a mis-speculation once tend to cause it again in the future. This is done in the context of ILP -- mis-speculation means that the processor thought an instruction doesn't need data from a previous one and it executed it in advance, but then it turned out that the result did depend on a previous one, so the first result was retired and the instruction was executed again.

In order to avoid this from happening too often, they added a(nother) feedback loop in the whole process: if a sequence of instructions seems to cause a mis-speculation often enough, it's added to a table, so that when it's encountered again, the control unit doesn't speculatively execute an instruction whose result is most likely going to have to be retired anyway.

I don't know if there's prior art to this, but the basic idea is fairly straightforward. I wouldn't be surprised to learn that IBM or DEC engineers knew about this prior to 1996.

Re: Apple facing huge chip patent bill after losing case

#17

Post by chucknelson »

bshimmin wrote: post #14
brownegg wrote: post #5

Earlier quoted context omitted.

If it's $862m, last I checked, it will take them about 30 hours to bring in the necessary revenue--if they want to pay out of profits (I'm totally guessing here, what are real net margins on their hardware? 15-20%?), it'll take a couple days.

Man, that's such a humbling stat. Many of us here don't even earn that in a year !

$862 million?

> Man, that's such a humbling stat. Many of us here don't even earn that in a lifetime!

FTFY

Unless I missed the /s ;)

Re: Apple facing huge chip patent bill after losing case

#18

Post by rwmj »

arbuge wrote: post #6
abluecloud wrote: post #2

$862m isn't that huge in the grand scheme of things. Not to mention, it's most likely not going to be $862m, my guess is it'll be less.

Given that large companies face large numbers of patent suits however, typically litigating several in parallel, spending all this money on just one could indeed be seen as distressing.

If it keeps smaller companies out of the market because they are not able to join patent cross-licensing cartels, then it may be a price worth paying.

Re: Apple facing huge chip patent bill after losing case

#19

Post by rwmj »

mtgx wrote: post #12

You know what they say: Live by the patent sword... Why doesn't Apple start lobbying for real patent reform?

Because it makes no sense for them to do so. Large companies join in cross-licensing agreements, keeping smaller competitors out. Occasionally some small player comes along with an important patent, and they refuse to be bought off and win in court. That makes the news like today because it happens so rarely. But it's a price worth paying to keep competition out of the market.

Competition is so tedious.

Re: Apple facing huge chip patent bill after losing case

#20

Post by samfisher83 »

timthorn wrote: post #10
trengrj wrote: post #4

Earlier quoted context omitted.

"Table based data speculation" - so a lookup table?? Would be interested in knowing how innovative the patent is from someone with more knowledge in this field.

Bear in mind the patent was filed in 1996 when considering the level of innovation.

Having a look up table for branch prediction? If something happens a lot it might happen in the future. That doesn't even sound that novel.
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