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Re: How can I generate a new function at compile time?

According to the output the ICE is in the newly generated function (_GLOBAL__N_bar)
which is the one that remains.
Further more the compilation continues until the
expand pass (outline.c.180r.expand), where the error happens.
The original function (bar) is last seen in outline.c.056i.comdats.
I am a little confused by that, since comdats does not change anything.
But maybe there is no connection between the violated assertion and the vanishing function.

On 03 Jun 2014, at 15:14, Richard Biener <richard.guenther@gmail.com> wrote:

> On Tue, Jun 3, 2014 at 3:03 PM, Benedikt Huber
> <benedikt.huber@theobroma-systems.com> wrote:
>> 
>> I have not found out why the assertion is violated, yet.
>> However I noticed that the original function disappears somehow between
>> the passes pass_ipa_comdats and pass_fixup_cfg.
>> By that I mean that the function appears from the dump files.
>> These passes run several passes after the outlining pass.
>> Between the outlining pass and pass_ipa_comdats both functions
>> (the generated and the original with the call to the generated) are printed.
>> I do not know whether this has anything to do with the assertion but it
>> seems strange.
>> Do you have any guess why this happens?
> 
> It probably vanishes because this is the function you ICE for?
> 
>> Thank you,
>> Benedikt
>> 
>> On 28 May 2014, at 15:50, Richard Biener <richard.guenther@gmail.com> wrote:
>> 
>>> On Wed, May 28, 2014 at 3:28 PM, Benedikt Huber
>>> <benedikt.huber@theobroma-systems.com> wrote:
>>>> I ported the pass to the fsf trunk. It is built with —enable-checking.
>>>> The patch applied with no changes and also the behaviour is the same.
>>>> So I probably mess up the cfg somehow.
>>>> Can you suggest any strategy for finding the problem that I could use?
>>>> 
>>>> /home/bhuber/sandbox/fsf/install/bin/gcc -O3 -c -fdump-tree-all-details -fdump-ipa-all-details -fdump-rtl-all-details -fno-ipa-cp -fnop-pass -funinline-innermost-loops -Wall -Wextra /home/bhuber/sandbox/try/outline.c
>>>> /home/bhuber/sandbox/try/outline.c: In function '_GLOBAL__N_bar':
>>>> /home/bhuber/sandbox/try/outline.c:3:1: internal compiler error: in purge_dead_edges, at cfgrtl.c:3179
>>>> bar (int s, int r, unsigned * t, int * k, int * p, int * l)
>>>> ^
>>>> 0x681195 purge_dead_edges(basic_block_def*)
>>>>       ../../src/gcc/cfgrtl.c:3179
>>>> 0xe64d8a find_bb_boundaries
>>>>       ../../src/gcc/cfgbuild.c:522
>>>> 0xe64d8a find_many_sub_basic_blocks(simple_bitmap_def*)
>>>>       ../../src/gcc/cfgbuild.c:604
>>>> 0x66e689 execute
>>>>       ../../src/gcc/cfgexpand.c:5905
>>>> Please submit a full bug report,
>>>> with preprocessed source if appropriate.
>>>> Please include the complete backtrace with any bug report.
>>>> See <http://gcc.gnu.org/bugs.html> for instructions.
>>> 
>>> Well, look at the CFG and see if it makes sense and why it expects
>>> a single successor and why there is none.  Basically, work back
>>> from the ICE ...
>>> 
>>> Richard.
>>> 
>>>> Best regards,
>>>> Benedikt
>>>> 
>>>> On 27 May 2014, at 17:35, Benedikt Huber <benedikt.huber@theobroma-systems.com> wrote:
>>>> 
>>>>> 
>>>>> On 27 May 2014, at 17:25, Richard Biener <richard.guenther@gmail.com> wrote:
>>>>> 
>>>>>> On Tue, May 27, 2014 at 5:17 PM, Benedikt Huber
>>>>>> <benedikt.huber@theobroma-systems.com> wrote:
>>>>>>> 
>>>>>>> On 27 May 2014, at 17:09, Richard Biener <richard.guenther@gmail.com> wrote:
>>>>>>> 
>>>>>>>> On Tue, May 27, 2014 at 5:03 PM, Benedikt Huber
>>>>>>>> <benedikt.huber@theobroma-systems.com> wrote:
>>>>>>>>> (Sorry for the duplicate.)
>>>>>>>>> 
>>>>>>>>> I managed to pass the needed parameters to the generated function.
>>>>>>>>> However I cannot pin down the reason why the compilation fails.
>>>>>>>>> It seems that the cfg is somehow broken, but I cannot tell how.
>>>>>>>>> Do you have any debugging hints?
>>>>>>>>> 
>>>>>>>>> As far as I can tell, the cfg is changed during the generation of the preheader
>>>>>>>>> (I do this to find the entry block easily.)
>>>>>>>>> and in the function move_sese_region_to_fn.
>>>>>>>>> 
>>>>>>>>> I noticed that after pass 058t.copyrename2 the original function bar disappears
>>>>>>>>> and the new function is replaced by _GLOBAL__N_bar.constprop, could this have
>>>>>>>>> anything to do with the problem?
>>>>>>>> 
>>>>>>>> Unlikely.  You can disable that by using -fno-ipa-cp.
>>>>>>>> 
>>>>>>>>> The pass runs just after the construction of cfg,  outline.c.011t.cfg.
>>>>>>>>> 
>>>>>>>>> /home/bhuber/sandbox/install/bin/gcc -O3 -I /home/bhuber/sandbox/src -c -fdump-tree-all-details -fdump-ipa-all-details -fdump-rtl-all-details -funinline-innermost-loops -Wall -Wextra /home/bhuber/sandbox/try/outline.c
>>>>>>>>> /home/bhuber/sandbox/try/outline.c: In function '_GLOBAL__N_bar.constprop':
>>>>>>>>> /home/bhuber/sandbox/try/outline.c:3:1: internal compiler error: in purge_dead_edges, at cfgrtl.c:3183
>>>>>>>> 
>>>>>>>> the line doesn't match anything that would ICE on current trunk, but I suppose
>>>>>>>> it's the single_succ_p assert that triggers?
>>>>>>> Yes, that is right, it is
>>>>>>> 
>>>>>>> gcc_assert (single_succ_p (bb));
>>>>>>> 
>>>>>>>> 
>>>>>>>> Either you really got until RTL generation or somehow cfgrtl cfg hooks are
>>>>>>>> still active while you are working in your pass.
>>>>>>> 
>>>>>>> The pass that fails, according to the dump files is outline.c.174r.expand
>>>>>>> So it already tries to generate RTL.
>>>>>>> My problem is that there are so many passes in
>>>>>>> between, that I do not know where to start looking.
>>>>>>> Any idea?
>>>>>> 
>>>>>> What code-base are you developing on?  Do you build with checking
>>>>>> enabled (--enable-checking, the default on trunk but not on release branches).
>>>>> 
>>>>> It is a linaro branch, but I am going to port the pass to the fsf trunk and see
>>>>> whether the behaviour changes.
>>>>> 
>>>>> Best regards,
>>>>> Benedikt
>>>>> 
>>>>>> 
>>>>>> Richard.
>>>>>> 
>>>>>>>> 
>>>>>>>> Richard.
>>>>>>>> 
>>>>>>>>> bar (int s, int r, unsigned * t, int * k, int * p, int * l)
>>>>>>>>> ^
>>>>>>>>> 0x67e7c4 purge_dead_edges(basic_block_def*)
>>>>>>>>>   ../../src/gcc/cfgrtl.c:3183
>>>>>>>>> 0xe5a0d6 find_bb_boundaries
>>>>>>>>>   ../../src/gcc/cfgbuild.c:522
>>>>>>>>> 0xe5a0d6 find_many_sub_basic_blocks(simple_bitmap_def*)
>>>>>>>>>   ../../src/gcc/cfgbuild.c:604
>>>>>>>>> 0x66c0f5 execute
>>>>>>>>>   ../../src/gcc/cfgexpand.c:5873
>>>>>>>>> Please submit a full bug report,
>>>>>>>>> with preprocessed source if appropriate.
>>>>>>>>> Please include the complete backtrace with any bug report.
>>>>>>>>> See <http://gcc.gnu.org/bugs.html> for instructions.
>>>>>>>>> 
>>>>>>>>> I attach the transformation pass and the small example program.
>>>>>>>>> 
>>>>>>>>> Thank you again for the help,
>>>>>>>>> Benedikt
>>>>>>>>> 
>>>>>>>>> P.s. I am aware that this transformation is not safe in general,
>>>>>>>>> however in this case it should work.
>>>>> 
>>>> 
>>
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