jacob navia via llvm-dev
2019-Apr-10 08:21 UTC
[llvm-dev] Feasibility of cling/llvm interpreter for JIT replacement
Dear Sir/Madam Our company, 4Js software, has developed an SQL data base software that runs under different operating systems: Windows, Linux, Mac OS X. This software compiles each SQL statement into a C program that is compiled "on the fly" and executed by our JIT, Just In Time compiler. We wanted to port it to Apple's iOS, and spent a lot of time retargetting the JIT for supporting the ARM 64 CPU, but to our surprise, when everything was ready, we learned that Apple iOS forbids software to generate dynamically an executable. After several months of reflections we think we can get around this problem by using a C interpreter. Instead of compiling it to machine code, we would pass the generated C program to a C interpreter that would interpret the C program. After looking at several interpreters, we think that the llvm based CLING interpreter could do the job. To test these ideas, we have recompiled the llvm/Clang system in a small linux/ARM64 based machine. Our preliminary tests seem to work and cling is able to load the generated program. There are several possible problems that we see. The first and most obvious one is the incredible size of the CLING interpreter (200MB stripped). Our whole data base is 80MB stripped. We are targetting an Apple iPad, boosted with 1TO SSD/6GB RAM. What would be the minimum requirements for CLING in terms of RAM size? The second question is that we have still concerns over the overall approach. Do you see any problems with this architecture? Can it work on principle? The third question concerns the feasibility of our JIT generating byte codes for the LLVM interpreter, boosting performance and reducing RAM footprint. Would that be a better solution than using the CLING interpreter? Is that possible within Apple's iOS? And yet another question is the need to modify the CLING interpreter so that it receives its input from a character buffer instead of a file, and other small tweaks. Is that possible? Are there any copyright issues? Are we allowed to embed the llvm software into our system? Of course we would publish any modifications done to the source code. We thank you in advance for any answers to the questions above. Yours sincerely Jacob Navia iOS Project Manager 4Js Software. https://4js.com 28 Quai Gallieni, 92150 Suresnes FRANCE -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20190410/b0fd224b/attachment.html>
mayuyu.io via llvm-dev
2019-Apr-10 09:33 UTC
[llvm-dev] Feasibility of cling/llvm interpreter for JIT replacement
Is there any reason not to use traditional approaches like ChaiScript? Zhang> 在 2019年4月10日，09:21，jacob navia via llvm-dev <llvm-dev at lists.llvm.org> 写道： > > Dear Sir/Madam > > > > Our company, 4Js software, has developed an SQL data base software that runs under different operating systems: Windows, Linux, Mac OS X. This software compiles each SQL statement into a C program that is compiled "on the fly" and executed by our JIT, Just In Time compiler. > > We wanted to port it to Apple's iOS, and spent a lot of time retargetting the JIT for supporting the ARM 64 CPU, but to our surprise, when everything was ready, we learned that Apple iOS forbids software to generate dynamically an executable. > > After several months of reflections we think we can get around this problem by using a C interpreter. Instead of compiling it to machine code, we would pass the generated C program to a C interpreter that would interpret the C program. > > After looking at several interpreters, we think that the llvm based CLING interpreter could do the job. To test these ideas, we have recompiled the llvm/Clang system in a small linux/ARM64 based machine. Our preliminary tests seem to work and cling is able to load the generated program. > > There are several possible problems that we see. > > > > The first and most obvious one is the incredible size of the CLING interpreter (200MB stripped). Our whole data base is 80MB stripped. We are targetting an Apple iPad, boosted with 1TO SSD/6GB RAM. What would be the minimum requirements for CLING in terms of RAM size? > > The second question is that we have still concerns over the overall approach. Do you see any problems with this architecture? Can it work on principle? > > The third question concerns the feasibility of our JIT generating byte codes for the LLVM interpreter, boosting performance and reducing RAM footprint. Would that be a better solution than using the CLING interpreter? Is that possible within Apple's iOS? > > And yet another question is the need to modify the CLING interpreter so that it receives its input from a character buffer instead of a file, and other small tweaks. Is that possible? > > Are there any copyright issues? Are we allowed to embed the llvm software into our system? Of course we would publish any modifications done to the source code. > > We thank you in advance for any answers to the questions above. > > > > Yours sincerely > > > > Jacob Navia > > iOS Project Manager > > 4Js Software. https://4js.com > 28 Quai Gallieni, 92150 Suresnes > > FRANCE > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20190410/b1124920/attachment.html>
Vassil Vassilev via llvm-dev
2019-Apr-10 10:49 UTC
[llvm-dev] Feasibility of cling/llvm interpreter for JIT replacement
Hi Jacob, On 4/10/19 11:21 AM, jacob navia via llvm-dev wrote:> > Dear Sir/Madam > > > Our company, 4Js software, has developed an SQL data base software > that runs under different operating systems: Windows, Linux, Mac OS X. > This software compiles each SQL statement into a C program that is > compiled "on the fly" and executed by our JIT, Just In Time compiler. > > We wanted to port it to Apple's iOS, and spent a lot of time > retargetting the JIT for supporting the ARM 64 CPU, but to our > surprise, when everything was ready, we learned that Apple iOS forbids > software to generate dynamically an executable. > > After several months of reflections we think we can get around this > problem by using a C interpreter. Instead of compiling it to machine > code, we would pass the generated C program to a C interpreter that > would interpret the C program. > > After looking at several interpreters, we think that the llvm based > CLING interpreter could do the job. To test these ideas, we have > recompiled the llvm/Clang system in a small linux/ARM64 based machine. > Our preliminary tests seem to work and cling is able to load the > generated program. > > There are several possible problems that we see. > > > The first and most obvious one is the incredible size of the CLING > interpreter (200MB stripped). Our whole data base is 80MB stripped. We > are targetting an Apple iPad, boosted with 1TO SSD/6GB RAM. >How do you do the strip? I have nightly releases of cling here: https://github.com/vgvassilev/cling/releases the release is around 23MB and unzipped is around 80. I am pretty sure we can strip it further down.> > What would be the minimum requirements for CLING in terms of RAM size? >That's a hard question: running `./bin/cling ".q"` shows around 23Mb peak rss. `./bin/cling "#include <vector>" ".q"` shows 34 Mb and so on. It depends on what sort of things you will be compiling/interpreting.> > The second question is that we have still concerns over the overall > approach. Do you see any problems with this architecture? Can it work > on principle? > > The third question concerns the feasibility of our JIT generating byte > codes for the LLVM interpreter, boosting performance and reducing RAM > footprint. Would that be a better solution than using the CLING > interpreter? Is that possible within Apple's iOS? > > And yet another question is the need to modify the CLING interpreter > so that it receives its input from a character buffer instead of a > file, and other small tweaks. Is that possible? >`./bin/cling '#include <iostream>' 'printf("hello world!\n");'` works. Did you mean a different use-case?> > Are there any copyright issues? Are we allowed to embed the llvm > software into our system? Of course we would publish any modifications > done to the source code. >I am not a lawyer. LLVM is licensed under a MIT-like (University of Illinois/NCSA) license (soon will be Apache-2.0). Cling is dual licensed under "UI/NCSAOSL" and "LGPL". Let me know if you need any further help on cling! Best, Vassil> We thank you in advance for any answers to the questions above. > > > Yours sincerely > > > Jacob Navia > > iOS Project Manager > > 4Js Software. https://4js.com > 28 Quai Gallieni, 92150 Suresnes > > FRANCE > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20190410/00d8d971/attachment-0001.html>
Dennis Luehring via llvm-dev
2019-Apr-10 11:27 UTC
[llvm-dev] Feasibility of cling/llvm interpreter for JIT replacement
chaiscript isn't very performant - far away from a real JITer Am 10.04.2019 um 11:33 schrieb mayuyu.io via llvm-dev:> Is there any reason not to use traditional approaches like ChaiScript? > > Zhang > > > 在 2019年4月10日，09:21，jacob navia via llvm-dev <llvm-dev at lists.llvm.org> 写道： > > > > Dear Sir/Madam > > > > > > > > Our company, 4Js software, has developed an SQL data base software that runs under different operating systems: Windows, Linux, Mac OS X. This software compiles each SQL statement into a C program that is compiled "on the fly" and executed by our JIT, Just In Time compiler. > > > > We wanted to port it to Apple's iOS, and spent a lot of time retargetting the JIT for supporting the ARM 64 CPU, but to our surprise, when everything was ready, we learned that Apple iOS forbids software to generate dynamically an executable. > > > > After several months of reflections we think we can get around this problem by using a C interpreter. Instead of compiling it to machine code, we would pass the generated C program to a C interpreter that would interpret the C program. > > > > After looking at several interpreters, we think that the llvm based CLING interpreter could do the job. To test these ideas, we have recompiled the llvm/Clang system in a small linux/ARM64 based machine. Our preliminary tests seem to work and cling is able to load the generated program. > > > > There are several possible problems that we see. > > > > > > > > The first and most obvious one is the incredible size of the CLING interpreter (200MB stripped). Our whole data base is 80MB stripped. We are targetting an Apple iPad, boosted with 1TO SSD/6GB RAM. What would be the minimum requirements for CLING in terms of RAM size? > > > > The second question is that we have still concerns over the overall approach. Do you see any problems with this architecture? Can it work on principle? > > > > The third question concerns the feasibility of our JIT generating byte codes for the LLVM interpreter, boosting performance and reducing RAM footprint. Would that be a better solution than using the CLING interpreter? Is that possible within Apple's iOS? > > > > And yet another question is the need to modify the CLING interpreter so that it receives its input from a character buffer instead of a file, and other small tweaks. Is that possible? > > > > Are there any copyright issues? Are we allowed to embed the llvm software into our system? Of course we would publish any modifications done to the source code. > > > > We thank you in advance for any answers to the questions above. > > > > > > > > Yours sincerely > > > > > > > > Jacob Navia > > > > iOS Project Manager > > > > 4Js Software. https://4js.com > > 28 Quai Gallieni, 92150 Suresnes > > > > FRANCE > > > > _______________________________________________ > > LLVM Developers mailing list > > llvm-dev at lists.llvm.org > > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
jacob navia via llvm-dev
2019-Apr-10 11:38 UTC
[llvm-dev] Feasibility of cling/llvm interpreter for JIT replacement
Le 10/04/2019 à 11:33, mayuyu.io a écrit :> Is there any reason not to use traditional approaches like ChaiScript? > > Zhang >Yes, that would mean generating chai script and not C, as it is done now. That would mean writing a new back end for a specific port to an specific architecture (iOS) and special casing all the backend of the SQL-->C compiler. That is (of course) doable, but it is a LOT of work.