On 01/20/2016 02:16 PM, Andreas Krebbel wrote:
> On 01/02/2016 08:16 PM, Marcin Kościelnicki wrote:
>> It seems at some point the .size hook was hijacked to emit some
>> machine-specific directives, and the actual .size directive was
>> forgotten. This caused problems for split-stack support, since
>> linker couldn't scan the function body for non-split-stack calls.
>>
>> gcc/ChangeLog:
>>
>> * config/s390/s390.c (s390_asm_declare_function_size): Add code
>> to actually emit the .size directive.
>
> ...
>
>> s390_asm_declare_function_size (FILE *asm_out_file,
>> - const char *fnname ATTRIBUTE_UNUSED, tree decl)
>> + const char *fnname, tree decl)
>> {
>> + if (!flag_inhibit_size_directive)
>> + ASM_OUTPUT_MEASURED_SIZE (asm_out_file, fnname);
>> if (DECL_FUNCTION_SPECIFIC_TARGET (decl) == NULL)
>> return;
>> fprintf (asm_out_file, "\t.machine pop\n");
>
> It would be good to use the original ASM_DECLARE_FUNCTION_SIZE macro from
> config/elfos.h here. This
> probably would require to change its name in s390.h first and then use it from
> s390_asm_declare_function_size. Not really beautiful but at least changes to
> the original macro
> would not require adjusting our backend.
I've looked into how the other archs are doing this and didn't find anything
better than just
including the code from the original macro. The real fix probably would be to
turn this into a
target hook instead.
I've committed the patch now since it fixes a real problem not only with
split-stack.
Thanks!
-Andreas-
