[PATCH v2 7/7] Fix the calculation of the function length

[Evgeny Karpov]

Wednesday, May 21
Richard Earnshaw (lists) <Richard.Earnshaw@arm.com> wrote:
>
>> +/* Sections are assumed to start aligned.  In executable section, there is no
>> +   MAP_DATA symbol pending.  So we only align the address during
>> +   MAP_DATA --> MAP_INSN transition.
>> +   For other sections, this is not guaranteed.  */
>>  #define md_do_align(N, FILL, LEN, MAX, LABEL)					\
>>    if (FILL == NULL && (N) != 0 && ! need_pass_2 && subseg_text_p (now_seg))	\
>>      {										\
>> -      frag_align_code (N, MAX);							\
>> +      enum mstate mapstate = seg_info (now_seg)->tc_segment_info_data.mapstate;	\
>> +      if (mapstate == MAP_DATA)							\
>> +	frag_align_code (N, MAX);						\
>>        goto LABEL;								\
>>      }
>>  
>
> Can you show a testcase for this please?  I'm trying to understand the issue you're trying to resolve.

Repro case:

.text
.seh_proc	test
.seh_endprologue
    mov x0, xzr
    .align 2 // Once this is removed, the expression for function size can be evaluated correctly
    ret
.seh_endproc

The fix aligns the code section only when it is in the MAP_DATA state.
In general, it is expected that this is not the case for executable sections.

The patch description will be extended with this repro case.

However, it looks like it breaks some tests on other platforms.
Any ideas what might be the issue?
https://patchwork.sourceware.org/project/binutils/patch/VI2PR83MB071806BA44D9B7485D1BEACEF88AA@VI2PR83MB0718.EURPRD83.prod.outlook.com/

Regards,
Evgeny