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

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 âenable-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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