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


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.

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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