Emanuele Del Sozzo via llvm-dev
2018-Aug-17 15:49 UTC
[llvm-dev] Replication -O3 optimizations manually
Hi Zide, I think I found the right way to reach my goal. I used the following command: clang -O3 -Xclang -disable-llvm-optzns main.c -S -emit-llvm -o main.ll to generate an IR file enriched by all the metadata that otherwise wouldn't be generated with -O0. Moreover, -disable-llvm-optzns flag ensures that none of the optimization passes has been applied yet to the IR. In this way, I can replicate -O3 result by applying the optimization passes using opt. Apparently, those metadata are necessary to fully optimize the code. I hope that this may help you too. Best regards Emanuele Del Sozzo ________________________________ From: llvm-dev <llvm-dev-bounces at lists.llvm.org> on behalf of Stefano Cherubin via llvm-dev <llvm-dev at lists.llvm.org> Sent: Friday, August 17, 2018 11:44:50 AM To: llvm-dev at lists.llvm.org; cszide Subject: Re: [llvm-dev] Replication -O3 optimizations manually Hi Zide, the scope of opt is limited to the LLVM-IR, which is meant to be always target independent. In order to apply backend optimizations you need to lower the representation to something closer to the machine-level. I would suggest you to measure performance on machine code, not LLVM-IR. To this end, please refer to the setup Emanuele is using. However, I may not have properly understood your test. lli is the LLVM-IR interpreter and it is meant more for functional testing rather than performance testing. Are you comparing the performance of machine code generated by clang -O3 against the performance of lli optimized_IR.bc ? Best regards, Stefano Cherubin On Friday, 17 August 2018, 03:55:52 CEST, cszide <cszide at 163.com> wrote: Hi, Stefano I also have the problem as described by Emanuele. You say that clang schedules target-independent and target-dependent passes. However, when I use lli to execute bitcode generated by opt with -O3 or with the same optimization passes as -O3, the performance are still different. So, are there some special operations by -O3 option? I read the source code of opt, but I cannot find the reason. Best regards Zide At 2018-08-16 22:13:14, "Stefano Cherubin via llvm-dev" <llvm-dev at lists.llvm.org> wrote: Hello Emanuele, When you provide the optimization level -O3 to the clang driver, it does not simply schedule a sequence of passes to be run on the intermediate representation. Indeed, it schedules target-independent and target-dependent passes. Moreover, IIRC, the optimization level is also used in the later stages of the code generation to apply target-dependent optimizations (i.e. vectorizer). The most common use case when someone wants to test its own pass/work within the LLVM toolchain is the following - use clang to generate a LLVM-IR file - use opt to run your desired pass / pass sequence and output another LLVM-IR file - use clang -O3 to compile to executable machine code However, with this approach you will run the passes on the LLVM-IR twice. There are use cases when this could invalidate your results. As opt stops at LLVM-IR level, I would suggest you to use also other LLVM tools to run individually the backend stages / sequence of passes which cannot be run by opt (such as llc / llvm-mc). An extensive list of tools/commands you can use is available at [0]. For your specific case, I would suggest you to have a look at this restricted schema [1]. Yet there is another way to get into even fine grain detail. You can check which are the clang DriverActions you are running with a given command line. See [2].>From that point you can rebuild the exact whole sequence of commands that the clang driver triggers.If you can provide more details about what is your use case (measure performance, pass development and testing, flag selection, phase ordering), we can suggest the most suitable approach. Kind regards, Stefano Cherubin [0] http://llvm.org/docs/CommandGuide/ [1] https://github.com/skeru/LLVM-intro/blob/master/img/03/toolchain.pdf [2] https://clang.llvm.org/docs/DriverInternals.html#driver-stages On Thursday, 16 August 2018, 12:46:04 CEST, Emanuele Del Sozzo via llvm-dev <llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote: Hello llvm-dev, my name is Emanuele and I am an intern in ARM. As part of the project I am doing here, I would like to manually replicate the optimizations that LLVM applies when I type -O3. In other words, I would like to know what are the compilation flags/passes that -O3 triggers. I noticed that GCC reports, on its website, all the flags that are enforced by -O3 (https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html), but I wasn't able to find something similar within LLVM documentation. On the other hand, I found that this command displays all the optimization passes applied by opt when -O3 flag is on: llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments I tried to apply the same optimization passes through opt, but, even though the performance are similar, the resulting binary is slower than the one generated using -O3 (also the binaries differ, of course). Again, I found this other command that does something similar (it lists the sequence of optimization passes applied): clang -O3 -mllvm -debug-pass=Arguments file.c In this case, the performance are still different and some of the optimization passes listed in the last block of passes (e.g. -machinemoduleinfo, -stack-protector, etc.) are unknown to opt. Said that, my question is: how can I find out what optimization passes/flags -O3 enforces in order to manually apply the same optimizations and have, hopefully, the same binary and performance? I am currently using LLVM version 5.0.2. Thank you for both your help and your time! Best regards Emanuele IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. _______________________________________________ LLVM Developers mailing list llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -------------- next part -------------- An HTML attachment was scrubbed... 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cszide via llvm-dev
2018-Aug-18 07:15 UTC
[llvm-dev] Replication -O3 optimizations manually
Hi Emanuele, Thank you for your replay! I cannot replicate -O3 result using LLVM 6.0 with the command you provide. Actually, I previously use the following command clang -O3 -Xclang -disable-llvm-passes -S -emit-llvm main.c -o main.ll to generate the IR file, which is equal to your command. Currently, I want to test the passes in LLVM. The performance of the pass or passes sequence is considered, so I choose the performance of -O3 as a baseline. The experiment steps are as following: 1. clang -O3 -Xclang -disable-llvm-passes -S -emit-llvm main.c -o main.ll 2.a. opt -O3 main.ll -o main-opt1.ll 2.b. opt (the same passes sequence as O3) main.ll -o main-opt2.ll 3.a llc main-opt1.ll -o main-opt1.s 3.b llc main-opt2.ll -o main-opt2.s 4.a clang main-opt1.s -o main-opt1 4.b clang main-opt2.s -o main-opt2 $ time ./main-opt1 real 0m0.846s user 0m0.845s sys 0m0.001s $ time ./main-opt2 real 0m0.956s user 0m0.956s sys 0m0.001s where the same passes sequence is generated by the following command: llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments From the results, we can see the execution time of main-opt2 is 13% lower than that of the main-opt1. As Stefano said, clang schedules target-independent and target-dependent passes. So I use lli to execute main-opt1.ll and main-opt2.ll to reduce the influence of target-dependent passes, the results are the same as the above. $ time lli main-opt1.ll real 0m0.878s user 0m0.878s sys 0m0.000s $ time lli main-opt2.ll real 0m0.978s user 0m0.978s sys 0m0.000s Thus, for my purpose, if I cannot get the same results using -O3 and the passes sequence as -O3, respectively, I cannot say that the performance comparisons between other passes sequence and -O3 are fair. I do not know whether I make some mistakes. In addition, I find that the passes sequences "-early-cse-memssa -lcssa-verification -early-cse-memssa", "-early-cse-memssa -verify -early-cse-memssa", "-early-cse-memssa -demanded-bits -early-cse-memssa" and "-early-cse-memssa -early-cse-memssa" will cause the following error for LLVM version 6.0.0. LLVMSymbolizer: error reading file: No such file or directory #0 0x0000000001a68794 (opt+0x1a68794) #1 0x0000000001a68a76 (opt+0x1a68a76) #2 0x00007f96a098c390 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x11390) #3 0x00000000015fc64e (opt+0x15fc64e) #4 0x000000000160065d (opt+0x160065d) #5 0x00000000015fdb08 (opt+0x15fdb08) #6 0x000000000075aaa6 (opt+0x75aaa6) #7 0x00007f969f924830 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x20830) #8 0x000000000074c1b9 (opt+0x74c1b9) Stack dump: 0. Program arguments: opt -early-cse-memssa -lcssa-verification -early-cse-memssa main.bc -o main-opt.bc Segmentation fault (core dumped) If possible, please try these passes sequences in your system using LLVM version 5.0.2. If these sequences also cause the same error in your system, it could be a bug for LLVM. Thank you for both your help and your time! Best regards Zide At 2018-08-17 23:49:38, "Emanuele Del Sozzo" <Emanuele.DelSozzo at arm.com> wrote: Hi Zide, I think I found the right way to reach my goal. I used the following command: clang -O3 -Xclang -disable-llvm-optzns main.c -S -emit-llvm -o main.ll to generate an IR file enriched by all the metadata that otherwise wouldn't be generated with -O0. Moreover, -disable-llvm-optzns flag ensures that none of the optimization passes has been applied yet to the IR. In this way, I can replicate -O3 result by applying the optimization passes using opt. Apparently, those metadata are necessary to fully optimize the code. I hope that this may help you too. Best regards Emanuele Del Sozzo From: llvm-dev <llvm-dev-bounces at lists.llvm.org> on behalf of Stefano Cherubin via llvm-dev <llvm-dev at lists.llvm.org> Sent: Friday, August 17, 2018 11:44:50 AM To:llvm-dev at lists.llvm.org; cszide Subject: Re: [llvm-dev] Replication -O3 optimizations manually Hi Zide, the scope of opt is limited to the LLVM-IR, which is meant to be always target independent. In order to apply backend optimizations you need to lower the representation to something closer to the machine-level. I would suggest you to measure performance on machine code, not LLVM-IR. To this end, please refer to the setup Emanuele is using. However, I may not have properly understood your test. lli is the LLVM-IR interpreter and it is meant more for functional testing rather than performance testing. Are you comparing the performance of machine code generated by clang -O3 against the performance of lli optimized_IR.bc ? Best regards, Stefano Cherubin On Friday, 17 August 2018, 03:55:52 CEST, cszide <cszide at 163.com> wrote: Hi, Stefano I also have the problem as described by Emanuele. You say that clang schedules target-independent and target-dependent passes. However, when I use lli to execute bitcode generated by opt with -O3 or with the same optimization passes as -O3, the performance are still different. So, are there some special operations by -O3 option? I read the source code of opt, but I cannot find the reason. Best regards Zide At 2018-08-16 22:13:14, "Stefano Cherubin via llvm-dev" <llvm-dev at lists.llvm.org> wrote: Hello Emanuele, When you provide the optimization level -O3 to the clang driver, it does not simply schedule a sequence of passes to be run on the intermediate representation. Indeed, it schedules target-independent and target-dependent passes. Moreover, IIRC, the optimization level is also used in the later stages of the code generation to apply target-dependent optimizations (i.e. vectorizer). The most common use case when someone wants to test its own pass/work within the LLVM toolchain is the following - use clang to generate a LLVM-IR file - use opt to run your desired pass / pass sequence and output another LLVM-IR file - use clang -O3 to compile to executable machine code However, with this approach you will run the passes on the LLVM-IR twice. There are use cases when this could invalidate your results. As opt stops at LLVM-IR level, I would suggest you to use also other LLVM tools to run individually the backend stages / sequence of passes which cannot be run by opt (such as llc / llvm-mc). An extensive list of tools/commands you can use is available at [0]. For your specific case, I would suggest you to have a look at this restricted schema [1]. Yet there is another way to get into even fine grain detail. You can check which are the clang DriverActions you are running with a given command line. See [2]. From that point you can rebuild the exact whole sequence of commands that the clang driver triggers. If you can provide more details about what is your use case (measure performance, pass development and testing, flag selection, phase ordering), we can suggest the most suitable approach. Kind regards, Stefano Cherubin [0] http://llvm.org/docs/CommandGuide/ [1] https://github.com/skeru/LLVM-intro/blob/master/img/03/toolchain.pdf [2] https://clang.llvm.org/docs/DriverInternals.html#driver-stages On Thursday, 16 August 2018, 12:46:04 CEST, Emanuele Del Sozzo via llvm-dev <llvm-dev at lists.llvm.org> wrote: Hello llvm-dev, my name is Emanuele and I am an intern in ARM. As part of the project I am doing here, I would like to manually replicate the optimizations that LLVM applies when I type -O3. In other words, I would like to know what are the compilation flags/passes that -O3 triggers. I noticed that GCC reports, on its website, all the flags that are enforced by -O3 (https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html), but I wasn't able to find something similar within LLVM documentation. On the other hand, I found that this command displays all the optimization passes applied by opt when -O3 flag is on: llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments I tried to apply the same optimization passes through opt, but, even though the performance are similar, the resulting binary is slower than the one generated using -O3 (also the binaries differ, of course). Again, I found this other command that does something similar (it lists the sequence of optimization passes applied): clang -O3 -mllvm -debug-pass=Arguments file.c In this case, the performance are still different and some of the optimization passes listed in the last block of passes (e.g. -machinemoduleinfo, -stack-protector, etc.) are unknown to opt. Said that, my question is: how can I find out what optimization passes/flags -O3 enforces in order to manually apply the same optimizations and have, hopefully, the same binary and performance? I am currently using LLVM version 5.0.2. Thank you for both your help and your time! Best regards Emanuele IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. _______________________________________________ LLVM Developers mailing list llvm-dev at lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20180818/5d5171d2/attachment.html>
Stefano Cherubin via llvm-dev
2018-Aug-18 09:49 UTC
[llvm-dev] Replication -O3 optimizations manually
Hi Zide,
thank you for the more detailed clarification of your setup.As far as I can see,
the only difference between your a) steps and b) steps lies in the sequence of
passes you provide them.Obviously the sequence of passes you get from [1] is not
the same as the sequence of passes opt runs on your main.llI suggest you to use
the same command as [1] with the actual input of your benchmark as input for
opt. See [2].
I crafted a main.c file with an empty main and I run your step 1 to generate the
LLVM-IR.I compared the output of [1] against the output of [2] and I noticed a
small difference.Indeed, [2] schedules one more pass (-targetpassconfig) with
respect to [1].
I also tried to craft another main.ll file via llvm-stress (LLVM utility to
generate random valid LLVM-IR test files).In this case [1] and [2] do not
differ.
I guess the difference of scheduled passes is due to source code metadata which
have been transferred to the IR from the source file.I suspect that if you feed
[2] with a full benchmark (I don't know which one you are using) you may get
a slightly different sequence of passes.
I hope this could help you.
Best regards,
Stefano Cherubin
[1] llvm-as < /dev/null | opt -O3 -disable-output
-debug-pass=Arguments[2] opt -O3 -disable-output -debug-pass=Arguments main.ll
On Saturday, 18 August 2018, 09:16:20 CEST, cszide via llvm-dev <llvm-dev
at lists.llvm.org> wrote:
Hi Emanuele,
Thank you for your replay!
I cannot replicate -O3 result using LLVM 6.0 with the command you provide.
Actually, I previously use the following command
clang -O3 -Xclang -disable-llvm-passes -S -emit-llvm main.c -o main.ll to
generate the IR file, which is equal to your command.
Currently, I want to test the passes in LLVM. The performance of the pass or
passes sequence is considered, so I choose the performance
of -O3 as a baseline.
The experiment steps are as following:
1. clang -O3 -Xclang -disable-llvm-passes -S -emit-llvm main.c -o main.ll
2.a. opt -O3 main.ll -o main-opt1.ll
2.b. opt (the same passes sequence as O3) main.ll -o main-opt2.ll
3.a llc main-opt1.ll -o main-opt1.s
3.b llc main-opt2.ll -o main-opt2.s
4.a clang main-opt1.s -o main-opt1
4.b clang main-opt2.s -o main-opt2
$ time ./main-opt1
real 0m0.846s
user 0m0.845s
sys 0m0.001s
$ time ./main-opt2
real 0m0.956s
user 0m0.956s
sys 0m0.001s
where the same passes sequence is generated by the following command:
llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments
>From the results, we can see the execution time of main-opt2 is 13% lower
than that of the main-opt1.
As Stefano said, clang schedules target-independent and target-dependent passes.
So I use lli to execute main-opt1.ll and main-opt2.ll
to reduce the influence of target-dependent passes, the results are the same as
the above.
$ time lli main-opt1.ll
real 0m0.878s
user 0m0.878s
sys 0m0.000s
$ time lli main-opt2.ll
real 0m0.978s
user 0m0.978s
sys 0m0.000s
Thus, for my purpose, if I cannot get the same results using -O3 and the passes
sequence as -O3, respectively, I cannot say
that the performance comparisons between other passes sequence and -O3 are fair.
I do not know whether I make some mistakes.
In addition, I find that the passes sequences "-early-cse-memssa
-lcssa-verification -early-cse-memssa",
"-early-cse-memssa -verify -early-cse-memssa", "-early-cse-memssa
-demanded-bits -early-cse-memssa" and "-early-cse-memssa
-early-cse-memssa"
will cause the following error for LLVM version 6.0.0.
LLVMSymbolizer: error reading file: No such file or directory
#0 0x0000000001a68794 (opt+0x1a68794)
#1 0x0000000001a68a76 (opt+0x1a68a76)
#2 0x00007f96a098c390 __restore_rt
(/lib/x86_64-linux-gnu/libpthread.so.0+0x11390)
#3 0x00000000015fc64e (opt+0x15fc64e)
#4 0x000000000160065d (opt+0x160065d)
#5 0x00000000015fdb08 (opt+0x15fdb08)
#6 0x000000000075aaa6 (opt+0x75aaa6)
#7 0x00007f969f924830 __libc_start_main
(/lib/x86_64-linux-gnu/libc.so.6+0x20830)
#8 0x000000000074c1b9 (opt+0x74c1b9)
Stack dump:
0. Program arguments: opt -early-cse-memssa -lcssa-verification
-early-cse-memssa main.bc -o main-opt.bc
Segmentation fault (core dumped)
If possible, please try these passes sequences in your system using LLVM version
5.0.2. If these sequences also cause the same error in your system,
it could be a bug for LLVM.
Thank you for both your help and your time!
Best regards
Zide
At 2018-08-17 23:49:38, "Emanuele Del Sozzo" <Emanuele.DelSozzo at
arm.com> wrote:
Hi Zide,
I think I found the right way to reach my goal.
I used the following command:
clang -O3 -Xclang -disable-llvm-optzns main.c -S -emit-llvm -o main.ll
to generate an IR file enriched by all the metadata that otherwise wouldn't
be generated with -O0. Moreover, -disable-llvm-optzns flag ensures that none of
the optimization passes has been applied yet to the IR.
In this way, I can replicate -O3 result by applying the optimization
passes using opt. Apparently, those metadata are necessary to fully optimize the
code.
I hope that this may help you too.
Best regards
Emanuele Del Sozzo
From: llvm-dev <llvm-dev-bounces at lists.llvm.org> on behalf of Stefano
Cherubin via llvm-dev <llvm-dev at lists.llvm.org>
Sent: Friday, August 17, 2018 11:44:50 AM
To: llvm-dev at lists.llvm.org; cszide
Subject: Re: [llvm-dev] Replication -O3 optimizations manually Hi Zide,
the scope of opt is limited to the LLVM-IR, which is meant to be always target
independent.In order to apply backend optimizations you need to lower the
representation to something closer to the machine-level.I would suggest you to
measure performance on machine code, not LLVM-IR.
To this end, please refer to the setup Emanuele is using.
However, I may not have properly understood your test.lli is the LLVM-IR
interpreter and it is meant more for functional testing rather than performance
testing.Are you comparing the performance of machine code generated by clang -O3
against the performance of lli optimized_IR.bc ?
Best regards,
Stefano Cherubin
On Friday, 17 August 2018, 03:55:52 CEST, cszide <cszide at 163.com>
wrote:
Hi, Stefano
I also have the problem as described by Emanuele. You say that clang schedules
target-independent and target-dependent passes.
However, when I use lli to execute bitcode generated by opt with -O3 or with the
same optimization passes as -O3, the performance are still different.
So, are there some special operations by -O3 option? I read the source code of
opt, but I cannot find the reason.
Best regards
Zide
At 2018-08-16 22:13:14, "Stefano Cherubin via llvm-dev" <llvm-dev
at lists.llvm.org> wrote:
Hello Emanuele,
When you provide the optimization level -O3 to the clang driver, it does not
simply schedule a sequence of passes to be run on the intermediate
representation.Indeed, it schedules target-independent and target-dependent
passes.Moreover, IIRC, the optimization level is also used in the later stages
of the code generation to apply target-dependent optimizations (i.e.
vectorizer).
The most common use case when someone wants to test its own pass/work within the
LLVM toolchain is the following
- use clang to generate a LLVM-IR file- use opt to run your desired pass / pass
sequence and output another LLVM-IR file- use clang -O3 to compile to executable
machine code
However, with this approach you will run the passes on the LLVM-IR twice.There
are use cases when this could invalidate your results.As opt stops at LLVM-IR
level, I would suggest you to use also other LLVM tools to run individually the
backend stages / sequence of passes which cannot be run by opt (such as llc /
llvm-mc).An extensive list of tools/commands you can use is available at [0].For
your specific case, I would suggest you to have a look at this restricted schema
[1].
Yet there is another way to get into even fine grain detail.You can check which
are the clang DriverActions you are running with a given command line. See
[2].From that point you can rebuild the exact whole sequence of commands that
the clang driver triggers.
If you can provide more details about what is your use case (measure
performance, pass development and testing, flag selection, phase ordering), we
can suggest the most suitable approach.
Kind regards,
Stefano Cherubin
[0] http://llvm.org/docs/CommandGuide/[1]
https://github.com/skeru/LLVM-intro/blob/master/img/03/toolchain.pdf[2]
https://clang.llvm.org/docs/DriverInternals.html#driver-stages
On Thursday, 16 August 2018, 12:46:04 CEST, Emanuele Del Sozzo via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
Hello llvm-dev,
my name is Emanuele and I am an intern in ARM. As part of the project I am doing
here, I would like to manually replicate the optimizations that LLVM applies
when I type -O3. In other words, I would like to know what are the compilation
flags/passes that -O3 triggers.
I noticed that GCC reports, on its website, all the flags that are enforced by
-O3 (https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html), but I wasn't
able to find something similar within LLVM documentation. On the other hand, I
found that this command displays all the optimization passes applied by opt when
-O3 flag is on:
llvm-as < /dev/null | opt -O3 -disable-output -debug-pass=Arguments
I tried to apply the same optimization passes through opt, but, even though the
performance are similar, the resulting binary is slower than the one generated
using -O3 (also the binaries differ, of course).
Again, I found this other command that does something similar (it lists the
sequence of optimization passes applied):
clang -O3 -mllvm -debug-pass=Arguments file.c
In this case, the performance are still different and some of the optimization
passes listed in the last block of passes (e.g. -machinemoduleinfo,
-stack-protector, etc.) are unknown to opt.
Said that, my question is: how can I find out what optimization passes/flags -O3
enforces in order to manually apply the same optimizations and have, hopefully,
the same binary and performance?
I am currently using LLVM version 5.0.2.
Thank you for both your help and your time!
Best regards
Emanuele
IMPORTANT NOTICE: The contents of this email and any attachments are
confidential and may also be privileged. If you are not the intended recipient,
please notify the sender immediately and do not disclose the contents to any
other person, use it for any purpose, or store or copy the information in any
medium. Thank you. _______________________________________________
LLVM Developers mailing list
llvm-dev at lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
IMPORTANT NOTICE: The contents of this email and any attachments are
confidential and may also be privileged. If you are not the intended recipient,
please notify the sender immediately and do not disclose the contents to any
other person, use it for any purpose, or store or copy the information in any
medium. Thank you.
_______________________________________________
LLVM Developers mailing list
llvm-dev at lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
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