[Bug gcov-profile/97917] New: [GCOV]incorrect code coverage for intrinsics

[Bug gcov-profile/97917] New: [GCOV]incorrect code coverage for intrinsics

[yangyibiao at outlook dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97917

            Bug ID: 97917
           Summary: [GCOV]incorrect code coverage for intrinsics
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: gcov-profile
          Assignee: unassigned at gcc dot gnu.org
          Reporter: yangyibiao at outlook dot com
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

$ cat test.c
#include <x86intrin.h>

typedef double D __attribute__((may_alias));
__attribute__((aligned(16))) static const double r[4] = { 1., 5., 1., 3. };

__attribute__((noinline, noclone))
void foo (int x) { return; }

int main ()
{
  __m128d t = _mm_set1_pd (5.);
  ((D *)(&t))[0] = 1.;
  foo (_mm_movemask_pd (_mm_cmpeq_pd (t, _mm_load_pd (&r[0]))));
  return 0;
}


$ gcc -O0 --coverage test.c; ./a.out; gcov test.c; cat test.c.gcov
File 'test.c'
Lines executed:100.00% of 6
Creating 'test.c.gcov'

File '/usr/gcc-trunk/lib/gcc/x86_64-pc-linux-gnu/10.0.1/include/emmintrin.h'
Lines executed:100.00% of 4
Creating 'emmintrin.h.gcov'

        -:    0:Source:test.c
        -:    0:Graph:test.gcno
        -:    0:Data:test.gcda
        -:    0:Runs:1
        -:    1:#include <x86intrin.h>
        -:    2:
        -:    3:typedef double D __attribute__((may_alias));
        -:    4:__attribute__((aligned(16))) static const double r[4] = { 1.,
5., 1., 3. };
        -:    5:
        -:    6:__attribute__((noinline, noclone))
        1:    7:void foo (int x) { return; }
        -:    8:
        1:    9:int main ()
        -:   10:{
        1:   11:  __m128d t = _mm_set1_pd (5.);
        1:   12:  ((D *)(&t))[0] = 1.;
        3:   13:  foo (_mm_movemask_pd (_mm_cmpeq_pd (t, _mm_load_pd
(&r[0]))));
        1:   14:  return 0;
        -:   15:}

############################
Line #13 is wrongly marked as executed 3 times.
When debug this program in gdb, Line #13 is hit only once.

[Bug gcov-profile/97917] [GCOV]incorrect code coverage for intrinsics

[yangyibiao at outlook dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97917

--- Comment #1 from Yibiao Yang <yangyibiao at outlook dot com> ---
$ gcc --version; gcov --version
gcc (GCC) 10.0.1 20200419 (experimental)
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

gcov (GCC) 10.0.1 20200419 (experimental)
Copyright (C) 2020 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or 
FITNESS FOR A PARTICULAR PURPOSE.

[Bug gcov-profile/97917] [GCOV]incorrect code coverage for intrinsics

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97917

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2020-11-20
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
Confirmed.

Related to fact that we "jump" to another code before moving back to line 13:

  __P_18 = [pr97917.c:13:3] &[pr97917.c:13:57] r[0];
  [/usr/lib64/gcc/x86_64-suse-linux/10/include/emmintrin.h:124:10] _19 =
MEM[(__m128d * {ref-all})__P_18];

  <bb 5> :
<L4>:
  _23 = _19;

  <bb 6> :
  [pr97917.c:13:3] _3 = _23;
  [pr97917.c:13:3] t.1_4 = t;
  __A_15 = t.1_4;
  __B_16 = _3;
  [/usr/lib64/gcc/x86_64-suse-linux/10/include/emmintrin.h:358:19] _17 =
__builtin_ia32_cmpeqpd (__A_15, __B_16);

  <bb 7> :
<L3>:
  _24 = _17;

  <bb 8> :
  [pr97917.c:13:3] _5 = _24;
  __A_13 = _5;
  [/usr/lib64/gcc/x86_64-suse-linux/10/include/emmintrin.h:958:10] _14 =
__builtin_ia32_movmskpd (__A_13);