llvm dev - May 2018 - Rewriting calls to varargs functions

It could save useless parsing in s/f/printf during runtime.

E.g. for heavy "fprint"ing code like fprintf(f, "%s: %s",
TAG, msg); I
think it could be quite useful.
After this transformation we would get fprintf(f, "ABC: %s", msg); 
--> We
could save one push/mov instruction + less parsing in printf every time we
call it. We would just replace string constant "%s: %s" with
"ABC: %s" and
possibly orphaned "ABC" constant could be removed completely.



2018-05-22 18:36 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>
> On 05/22/2018 10:42 AM, Dávid Bolvanský wrote:
>
> Thanks.
>
> Yes, to substitute only some of the arguments. Formatting used by printf
> depends on the locale but only for double, float types I think - yes, I
> would not place double/float constants into the format string.
>
>
> Okay. I think it's true that integers will be the same regardless of
> locale (so long as the ' flag is not used, as that brings in a
dependence
> on LC_NUMERIC).
>
>
> Why? To reduce number of constants (some of them could be merged into the
> format string) and number of args when calling printf/fprintf/sprintf,
> etc..
>
>
> Sure, but it seems to me unlikely that this will affect performance. Is it
> a code-size optimization (this actually isn't obvious to me because the
> string representation might be longer than the binary form of the constant
> plus the extra instructions)?
>
>  -Hal
>
>
>
> 2018-05-22 16:22 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>
>>
>> On 05/22/2018 04:32 AM, Dávid Bolvanský via llvm-dev wrote:
>>
>> Hello,
>>
>> A new patch:
>> https://reviews.llvm.org/D47159
>>
>> proposes transformations like:
>> printf("Hello, %s %d", "world", 123) - >
printf("Hello world 123")
>>
>>
>> To clarify, the real question here comes up when you can only
substitute
>> some of the arguments? If you can substitute all of the arguments, then
you
>> can turn this into a call to puts.
>>
>> In any case , why do you want to do this? Also, doesn't the
formatting
>> used by printf depend on the process's current locale?
>>
>>  -Hal
>>
>>
>> As Eli noted:
>>
>> "I'm not sure we can rewrite calls to varargs functions safely
in general
>> given the current state of the C ABI rules in LLVM.
>>
>> Sometimes clang does weird things to conform with the ABI rules,
because
>> the LLVM type system isn't the same as the C system. For most
functions,
>> it's pretty easy to tell it happened: if the IR signature of the
function
>> doesn't match the expected signature, something weird happened, so
we can
>> just bail out. But varargs functions don't specify a complete
signature, so
>> we can't tell if the clang ABI code was forced to do something
weird, like
>> split an argument into multiple values, or insert a padding value. For
>> example, for the target mips64-unknown-linux-gnu, a call like
>> printf("asdf%Lf", 1.0L); gets lowered to the following:
>>
>> %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5 x
i8],
>> [5 x i8]* @.str, i32 0, i32 0), i64 undef, fp128
>> 0xL00000000000000003FFF000000000000) #2"
>>
>>
>> I would to hear more suggestions whether it is safe or not. Seems like
>> for mips Clang produces some weird IR, but e.g. x86 IR seems ok.
>>
>> Any folks from Clang/LLVM to bring more information about "varargs
vs ABI
>> vs LLVM vs Clang"?
>> And whether we can rewrite calls to varargs functions safely under some
>> conditions..
>>
>> Thanks
>>
>>
>>
>>
>> _______________________________________________
>> LLVM Developers mailing listllvm-dev at
lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>>
>> --
>> Hal Finkel
>> Lead, Compiler Technology and Programming Languages
>> Leadership Computing Facility
>> Argonne National Laboratory
>>
>>
>
> --
> Hal Finkel
> Lead, Compiler Technology and Programming Languages
> Leadership Computing Facility
> Argonne National Laboratory
>
>
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On Tue, May 22, 2018 at 12:59 PM, Dávid Bolvanský via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> It could save useless parsing in s/f/printf during runtime.
>
A mix of calls to puts and calls to printf with format strings containing
just a conversion specifier can help towards such a goal without mutating
constants beyond the format string.

>
> E.g. for heavy "fprint"ing code like fprintf(f, "%s:
%s", TAG, msg); I
> think it could be quite useful.
> After this transformation we would get fprintf(f, "ABC: %s",
msg);  --> We
> could save one push/mov instruction + less parsing in printf every time we
> call it. We would just replace string constant "%s: %s" with
"ABC: %s" and
> possibly orphaned "ABC" constant could be removed completely.
>
>
>
> 2018-05-22 18:36 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>
>>
>> On 05/22/2018 10:42 AM, Dávid Bolvanský wrote:
>>
>> Thanks.
>>
>> Yes, to substitute only some of the arguments. Formatting used by
printf
>> depends on the locale but only for double, float types I think - yes, I
>> would not place double/float constants into the format string.
>>
>>
>> Okay. I think it's true that integers will be the same regardless
of
>> locale (so long as the ' flag is not used, as that brings in a
dependence
>> on LC_NUMERIC).
>>
>>
>> Why? To reduce number of constants (some of them could be merged into
the
>> format string) and number of args when calling printf/fprintf/sprintf,
>> etc..
>>
>>
>> Sure, but it seems to me unlikely that this will affect performance. Is
>> it a code-size optimization (this actually isn't obvious to me
because the
>> string representation might be longer than the binary form of the
constant
>> plus the extra instructions)?
>>
>>  -Hal
>>
>>
>>
>> 2018-05-22 16:22 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>>
>>>
>>> On 05/22/2018 04:32 AM, Dávid Bolvanský via llvm-dev wrote:
>>>
>>> Hello,
>>>
>>> A new patch:
>>> https://reviews.llvm.org/D47159
>>>
>>> proposes transformations like:
>>> printf("Hello, %s %d", "world", 123) - >
printf("Hello world 123")
>>>
>>>
>>> To clarify, the real question here comes up when you can only
substitute
>>> some of the arguments? If you can substitute all of the arguments,
then you
>>> can turn this into a call to puts.
>>>
>>> In any case , why do you want to do this? Also, doesn't the
formatting
>>> used by printf depend on the process's current locale?
>>>
>>>  -Hal
>>>
>>>
>>> As Eli noted:
>>>
>>> "I'm not sure we can rewrite calls to varargs functions
safely in
>>> general given the current state of the C ABI rules in LLVM.
>>>
>>> Sometimes clang does weird things to conform with the ABI rules,
because
>>> the LLVM type system isn't the same as the C system. For most
functions,
>>> it's pretty easy to tell it happened: if the IR signature of
the function
>>> doesn't match the expected signature, something weird happened,
so we can
>>> just bail out. But varargs functions don't specify a complete
signature, so
>>> we can't tell if the clang ABI code was forced to do something
weird, like
>>> split an argument into multiple values, or insert a padding value.
For
>>> example, for the target mips64-unknown-linux-gnu, a call like
>>> printf("asdf%Lf", 1.0L); gets lowered to the following:
>>>
>>> %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5
x
>>> i8], [5 x i8]* @.str, i32 0, i32 0), i64 undef, fp128
>>> 0xL00000000000000003FFF000000000000) #2"
>>>
>>>
>>> I would to hear more suggestions whether it is safe or not. Seems
like
>>> for mips Clang produces some weird IR, but e.g. x86 IR seems ok.
>>>
>>> Any folks from Clang/LLVM to bring more information about
"varargs vs
>>> ABI vs LLVM vs Clang"?
>>> And whether we can rewrite calls to varargs functions safely under
some
>>> conditions..
>>>
>>> Thanks
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> LLVM Developers mailing listllvm-dev at
lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>
>>>
>>> --
>>> Hal Finkel
>>> Lead, Compiler Technology and Programming Languages
>>> Leadership Computing Facility
>>> Argonne National Laboratory
>>>
>>>
>>
>> --
>> Hal Finkel
>> Lead, Compiler Technology and Programming Languages
>> Leadership Computing Facility
>> Argonne National Laboratory
>>
>>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
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On 05/22/2018 11:59 AM, Dávid Bolvanský wrote:
> It could save useless parsing in s/f/printf during runtime.
Sure. But it is not clear that matters. printf is expensive anyway.
Maybe this matters more for snprintf? Have you benchmarked this?
>
> E.g. for heavy "fprint"ing code like fprintf(f, "%s:
%s", TAG, msg); I
> think it could be quite useful. 
> After this transformation we would get fprintf(f, "ABC: %s",
msg);
>  --> We could save one push/mov instruction + less parsing in printf
> every time we call it. We would just replace string constant "%s:
%s"
> with "ABC: %s" and possibly orphaned "ABC" constant
could be removed
> completely.
Possibly. You also might end up substituting the string into many other
strings, resulting in many other longer strings, and thus increasing the
size of the executable.

 -Hal
>
>
>
> 2018-05-22 18:36 GMT+02:00 Hal Finkel <hfinkel at anl.gov
> <mailto:hfinkel at anl.gov>>:
>
>
>     On 05/22/2018 10:42 AM, Dávid Bolvanský wrote:
>>     Thanks.
>>
>>     Yes, to substitute only some of the arguments. Formatting used by
>>     printf depends on the locale but only for double, float types I
>>     think - yes, I would not place double/float constants into the
>>     format string.
>
>     Okay. I think it's true that integers will be the same regardless
>     of locale (so long as the ' flag is not used, as that brings in a
>     dependence on LC_NUMERIC).
>
>>
>>     Why? To reduce number of constants (some of them could be merged
>>     into the format string) and number of args when
>>     calling printf/fprintf/sprintf, etc..
>
>     Sure, but it seems to me unlikely that this will affect
>     performance. Is it a code-size optimization (this actually isn't
>     obvious to me because the string representation might be longer
>     than the binary form of the constant plus the extra instructions)?
>
>      -Hal
>
>
>>
>>     2018-05-22 16:22 GMT+02:00 Hal Finkel <hfinkel at anl.gov
>>     <mailto:hfinkel at anl.gov>>:
>>
>>
>>         On 05/22/2018 04:32 AM, Dávid Bolvanský via llvm-dev wrote:
>>>         Hello,
>>>
>>>         A new patch:
>>>         https://reviews.llvm.org/D47159
>>>         <https://reviews.llvm.org/D47159>
>>>
>>>         proposes transformations like:
>>>         printf("Hello, %s %d", "world", 123) -
> printf("Hello world
>>>         123")
>>
>>         To clarify, the real question here comes up when you can only
>>         substitute some of the arguments? If you can substitute all
>>         of the arguments, then you can turn this into a call to puts.
>>
>>         In any case , why do you want to do this? Also, doesn't the
>>         formatting used by printf depend on the process's current
locale?
>>
>>          -Hal
>>
>>>
>>>         As Eli noted:
>>>
>>>         "I'm not sure we can rewrite calls to varargs
functions
>>>         safely in general given the current state of the C ABI
rules
>>>         in LLVM.
>>>
>>>         Sometimes clang does weird things to conform with the ABI
>>>         rules, because the LLVM type system isn't the same as
the C
>>>         system. For most functions, it's pretty easy to tell it
>>>         happened: if the IR signature of the function doesn't
match
>>>         the expected signature, something weird happened, so we can
>>>         just bail out. But varargs functions don't specify a
>>>         complete signature, so we can't tell if the clang ABI
code
>>>         was forced to do something weird, like split an argument
>>>         into multiple values, or insert a padding value. For
>>>         example, for the target mips64-unknown-linux-gnu, a call
>>>         like printf("asdf%Lf", 1.0L); gets lowered to the
following:
>>>
>>>         %call = call i32 (i8*, ...) @printf(i8* getelementptr
>>>         inbounds ([5 x i8], [5 x i8]* @.str, i32 0, i32 0), i64
>>>         undef, fp128 0xL00000000000000003FFF000000000000) #2"
>>>
>>>
>>>         I would to hear more suggestions whether it is safe or not.
>>>         Seems like for mips Clang produces some weird IR, but e.g.
>>>         x86 IR seems ok.
>>>
>>>         Any folks from Clang/LLVM to bring more information about
>>>         "varargs vs ABI vs LLVM vs Clang"? 
>>>         And whether we can rewrite calls to varargs functions
safely
>>>         under some conditions..
>>>
>>>         Thanks
>>>
>>>
>>>
>>>
>>>         _______________________________________________
>>>         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
>>>        
<http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev>
>>
>>         -- 
>>         Hal Finkel
>>         Lead, Compiler Technology and Programming Languages
>>         Leadership Computing Facility
>>         Argonne National Laboratory
>>
>>
>
>     -- 
>     Hal Finkel
>     Lead, Compiler Technology and Programming Languages
>     Leadership Computing Facility
>     Argonne National Laboratory
>
>
-- 
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory

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1.
1000000 x printf .. the time difference is cca 0.1s. No "benchmark"
for
fprintf/snprintf yet.

2.
We could disable this if "opt for size" or set a limit for lengths or
strings to be substituted.

3.
Anyway, I don't know if we can safely rewrite varargs. If is not possible
(we saw what had happened with printf on mips), then nothing to do here
anyway :)

2018-05-22 20:20 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>
> On 05/22/2018 11:59 AM, Dávid Bolvanský wrote:
>
> It could save useless parsing in s/f/printf during runtime.
>
>
> Sure. But it is not clear that matters. printf is expensive anyway. Maybe
> this matters more for snprintf? Have you benchmarked this?
>
>
> E.g. for heavy "fprint"ing code like fprintf(f, "%s:
%s", TAG, msg); I
> think it could be quite useful.
> After this transformation we would get fprintf(f, "ABC: %s",
msg);  --> We
> could save one push/mov instruction + less parsing in printf every time we
> call it. We would just replace string constant "%s: %s" with
"ABC: %s" and
> possibly orphaned "ABC" constant could be removed completely.
>
>
> Possibly. You also might end up substituting the string into many other
> strings, resulting in many other longer strings, and thus increasing the
> size of the executable.
>
>  -Hal
>
>
>
>
>
> 2018-05-22 18:36 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>
>>
>> On 05/22/2018 10:42 AM, Dávid Bolvanský wrote:
>>
>> Thanks.
>>
>> Yes, to substitute only some of the arguments. Formatting used by
printf
>> depends on the locale but only for double, float types I think - yes, I
>> would not place double/float constants into the format string.
>>
>>
>> Okay. I think it's true that integers will be the same regardless
of
>> locale (so long as the ' flag is not used, as that brings in a
dependence
>> on LC_NUMERIC).
>>
>>
>> Why? To reduce number of constants (some of them could be merged into
the
>> format string) and number of args when calling printf/fprintf/sprintf,
>> etc..
>>
>>
>> Sure, but it seems to me unlikely that this will affect performance. Is
>> it a code-size optimization (this actually isn't obvious to me
because the
>> string representation might be longer than the binary form of the
constant
>> plus the extra instructions)?
>>
>>  -Hal
>>
>>
>>
>> 2018-05-22 16:22 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>>
>>>
>>> On 05/22/2018 04:32 AM, Dávid Bolvanský via llvm-dev wrote:
>>>
>>> Hello,
>>>
>>> A new patch:
>>> https://reviews.llvm.org/D47159
>>>
>>> proposes transformations like:
>>> printf("Hello, %s %d", "world", 123) - >
printf("Hello world 123")
>>>
>>>
>>> To clarify, the real question here comes up when you can only
substitute
>>> some of the arguments? If you can substitute all of the arguments,
then you
>>> can turn this into a call to puts.
>>>
>>> In any case , why do you want to do this? Also, doesn't the
formatting
>>> used by printf depend on the process's current locale?
>>>
>>>  -Hal
>>>
>>>
>>> As Eli noted:
>>>
>>> "I'm not sure we can rewrite calls to varargs functions
safely in
>>> general given the current state of the C ABI rules in LLVM.
>>>
>>> Sometimes clang does weird things to conform with the ABI rules,
because
>>> the LLVM type system isn't the same as the C system. For most
functions,
>>> it's pretty easy to tell it happened: if the IR signature of
the function
>>> doesn't match the expected signature, something weird happened,
so we can
>>> just bail out. But varargs functions don't specify a complete
signature, so
>>> we can't tell if the clang ABI code was forced to do something
weird, like
>>> split an argument into multiple values, or insert a padding value.
For
>>> example, for the target mips64-unknown-linux-gnu, a call like
>>> printf("asdf%Lf", 1.0L); gets lowered to the following:
>>>
>>> %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5
x
>>> i8], [5 x i8]* @.str, i32 0, i32 0), i64 undef, fp128
>>> 0xL00000000000000003FFF000000000000) #2"
>>>
>>>
>>> I would to hear more suggestions whether it is safe or not. Seems
like
>>> for mips Clang produces some weird IR, but e.g. x86 IR seems ok.
>>>
>>> Any folks from Clang/LLVM to bring more information about
"varargs vs
>>> ABI vs LLVM vs Clang"?
>>> And whether we can rewrite calls to varargs functions safely under
some
>>> conditions..
>>>
>>> Thanks
>>>
>>>
>>>
>>>
>>> _______________________________________________
>>> LLVM Developers mailing listllvm-dev at
lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>
>>>
>>> --
>>> Hal Finkel
>>> Lead, Compiler Technology and Programming Languages
>>> Leadership Computing Facility
>>> Argonne National Laboratory
>>>
>>>
>>
>> --
>> Hal Finkel
>> Lead, Compiler Technology and Programming Languages
>> Leadership Computing Facility
>> Argonne National Laboratory
>>
>>
>
> --
> Hal Finkel
> Lead, Compiler Technology and Programming Languages
> Leadership Computing Facility
> Argonne National Laboratory
>
>
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Converting to puts is usually not possible: puts appends a newline to its
output. The only really appropriate thing to convert to, that works in
general, is fwrite. But we can't convert to that because we can't form
the
'stdout' parameter (stdout might be a macro rather than a global, or
might
have a nontrivial mangling, so LLVM can't synthesize it). Also, converting
printf("Hello, %s", "world") to printf("Hello,
world") is likely a
pessimization rather than an optimization for performance: printing a
string via %s just needs to write the string, whereas printing a format
string needs to scan for %s.

Having said all that, the opposite conversion (from printf("Hello,
%s",
"world") to printf("%s", "Hello, world")) may be
marginally worthwhile. And
there are some non-trivial tradeoffs here if you want to optimize for size.
(Eg, some format string refactorings may permit more string constant reuse.)

On 22 May 2018 at 10:26, Hubert Tong via llvm-dev <llvm-dev at
lists.llvm.org>
wrote:
> On Tue, May 22, 2018 at 12:59 PM, Dávid Bolvanský via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> It could save useless parsing in s/f/printf during runtime.
>>
> A mix of calls to puts and calls to printf with format strings containing
> just a conversion specifier can help towards such a goal without mutating
> constants beyond the format string.
>
>
>>
>> E.g. for heavy "fprint"ing code like fprintf(f, "%s:
%s", TAG, msg); I
>> think it could be quite useful.
>> After this transformation we would get fprintf(f, "ABC: %s",
msg);  -->
>> We could save one push/mov instruction + less parsing in printf every
time
>> we call it. We would just replace string constant "%s: %s"
with "ABC: %s"
>> and possibly orphaned "ABC" constant could be removed
completely.
>>
>>
>>
>> 2018-05-22 18:36 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>>
>>>
>>> On 05/22/2018 10:42 AM, Dávid Bolvanský wrote:
>>>
>>> Thanks.
>>>
>>> Yes, to substitute only some of the arguments. Formatting used by
>>> printf depends on the locale but only for double, float types I
think -
>>> yes, I would not place double/float constants into the format
string.
>>>
>>>
>>> Okay. I think it's true that integers will be the same
regardless of
>>> locale (so long as the ' flag is not used, as that brings in a
dependence
>>> on LC_NUMERIC).
>>>
>>>
>>> Why? To reduce number of constants (some of them could be merged
into
>>> the format string) and number of args when calling
printf/fprintf/sprintf,
>>> etc..
>>>
>>>
>>> Sure, but it seems to me unlikely that this will affect
performance. Is
>>> it a code-size optimization (this actually isn't obvious to me
because the
>>> string representation might be longer than the binary form of the
constant
>>> plus the extra instructions)?
>>>
>>>  -Hal
>>>
>>>
>>>
>>> 2018-05-22 16:22 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:
>>>
>>>>
>>>> On 05/22/2018 04:32 AM, Dávid Bolvanský via llvm-dev wrote:
>>>>
>>>> Hello,
>>>>
>>>> A new patch:
>>>> https://reviews.llvm.org/D47159
>>>>
>>>> proposes transformations like:
>>>> printf("Hello, %s %d", "world", 123) - >
printf("Hello world 123")
>>>>
>>>>
>>>> To clarify, the real question here comes up when you can only
>>>> substitute some of the arguments? If you can substitute all of
the
>>>> arguments, then you can turn this into a call to puts.
>>>>
>>>> In any case , why do you want to do this? Also, doesn't the
formatting
>>>> used by printf depend on the process's current locale?
>>>>
>>>>  -Hal
>>>>
>>>>
>>>> As Eli noted:
>>>>
>>>> "I'm not sure we can rewrite calls to varargs
functions safely in
>>>> general given the current state of the C ABI rules in LLVM.
>>>>
>>>> Sometimes clang does weird things to conform with the ABI
rules,
>>>> because the LLVM type system isn't the same as the C
system. For most
>>>> functions, it's pretty easy to tell it happened: if the IR
signature of the
>>>> function doesn't match the expected signature, something
weird happened, so
>>>> we can just bail out. But varargs functions don't specify a
complete
>>>> signature, so we can't tell if the clang ABI code was
forced to do
>>>> something weird, like split an argument into multiple values,
or insert a
>>>> padding value. For example, for the target
mips64-unknown-linux-gnu, a call
>>>> like printf("asdf%Lf", 1.0L); gets lowered to the
following:
>>>>
>>>> %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds
([5 x
>>>> i8], [5 x i8]* @.str, i32 0, i32 0), i64 undef, fp128
>>>> 0xL00000000000000003FFF000000000000) #2"
>>>>
>>>>
>>>> I would to hear more suggestions whether it is safe or not.
Seems like
>>>> for mips Clang produces some weird IR, but e.g. x86 IR seems
ok.
>>>>
>>>> Any folks from Clang/LLVM to bring more information about
"varargs vs
>>>> ABI vs LLVM vs Clang"?
>>>> And whether we can rewrite calls to varargs functions safely
under some
>>>> conditions..
>>>>
>>>> Thanks
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> LLVM Developers mailing listllvm-dev at
lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>>>
>>>>
>>>> --
>>>> Hal Finkel
>>>> Lead, Compiler Technology and Programming Languages
>>>> Leadership Computing Facility
>>>> Argonne National Laboratory
>>>>
>>>>
>>>
>>> --
>>> Hal Finkel
>>> Lead, Compiler Technology and Programming Languages
>>> Leadership Computing Facility
>>> Argonne National Laboratory
>>>
>>>
>>
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
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