llvm dev - Sep 2019 - Question about using multiple functions in a Function pass

Hi all,
I would want to know if from the runOnFunction method of a Function pass, other
functions in IR, except for the one received as parameter, can be obtained as
well, from a call instruction, as follows:
Function F = dyn_cast<Function>(callInst);
Or do I need a Module pass to work in IR with multiple functions from input
source code? If so, it is accepted to have O(n^3) complexity in a module pass
when iterating through each instruction of each basic block of each function in
the module.
Unrelated to the topic, I would also like to ask if a module object contains the
IR for the entire application if the application contains multiple source files?

Kind regards,
Iulia ȘTIRB




-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20190910/251e6a6b/attachment.html>

Forgot one question to the mail and a correction below:
When calling runOnFunction for a function in IR is it guaranteed that all other
functions in the module are already parsed by the compiler?

Thank you,Iulia

 

    On Tuesday, September 10, 2019, 6:56:39 PM GMT+3, Iulia Stirb <iulia_s24
at yahoo.com> wrote:
 
 Hi all,
I would want to know if from the runOnFunction method of a Function pass, other
functions in IR, except for the one received as parameter, can be obtained as
well, from a call instruction, as follows:
Function * F = dyn_cast<Function>(callInst);
Or do I need a Module pass to work in IR with multiple functions from input
source code? If so, it is accepted to have O(n^3) complexity in a module pass
when iterating through each instruction of each basic block of each function in
the module.
Unrelated to the topic, I would also like to ask if a module object contains the
IR for the entire application if the application contains multiple source files?

Kind regards,
Iulia ȘTIRB




  
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20190910/7070274a/attachment.html>

Hi Iulia,

Function passes are not allowed to process functions other than the current
one. Please see
http://llvm.org/docs/WritingAnLLVMPass.html#the-functionpass-class

Alex

On Tue., Sep. 10, 2019, 11:56 a.m. Iulia Stirb via llvm-dev, <
llvm-dev at lists.llvm.org> wrote:
> Hi all,
>
> I would want to know if from the runOnFunction method of a Function pass,
> other functions in IR, except for the one received as parameter, can be
> obtained as well, from a call instruction, as follows:
>
> Function F = dyn_cast<Function>(callInst);
>
> Or do I need a Module pass to work in IR with multiple functions from
> input source code? If so, it is accepted to have O(n^3) complexity in a
> module pass when iterating through each instruction of each basic block of
> each function in the module.
>
> Unrelated to the topic, I would also like to ask if a module object
> contains the IR for the entire application if the application contains
> multiple source files?
>
> Kind regards,
> Iulia ȘTIRB
>
>
>
>
>
> _______________________________________________
> 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/20190910/8a7860a8/attachment.html>

My understanding is that a pass type is supposed not to operate
outside its scope (module, function, loop, etc.) because the pass
manager might choose to 'batch' multiple passes of the same type (for
performance) or could run concurrently. It sounds like it's best to
use a module pass if the other functions in the same module need to be
read.

On Tue, Sep 10, 2019 at 11:46 AM Alexey Zhikhartsev via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
>
> Hi Iulia,
>
> Function passes are not allowed to process functions other than the current
one. Please see
http://llvm.org/docs/WritingAnLLVMPass.html#the-functionpass-class
>
> Alex
>
> On Tue., Sep. 10, 2019, 11:56 a.m. Iulia Stirb via llvm-dev, <llvm-dev
at lists.llvm.org> wrote:
>>
>> Hi all,
>>
>> I would want to know if from the runOnFunction method of a Function
pass, other functions in IR, except for the one received as parameter, can be
obtained as well, from a call instruction, as follows:
>>
>> Function F = dyn_cast<Function>(callInst);
>>
>> Or do I need a Module pass to work in IR with multiple functions from
input source code? If so, it is accepted to have O(n^3) complexity in a module
pass when iterating through each instruction of each basic block of each
function in the module.
>>
>> Unrelated to the topic, I would also like to ask if a module object
contains the IR for the entire application if the application contains multiple
source files?
>>
>> Kind regards,
>> Iulia ȘTIRB
>>
>>
>>
>>
>>
>> _______________________________________________
>> 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