https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125741
--- Comment #1 from Drea Pinski <pinskia at gcc dot gnu.org> ---
The first difference is __STDCPP_DEFAULT_NEW_ALIGNMENT__ is 8 for arm while 16
for ia32.
And then with that difference there seems to be a jump threading which creates
duplicates the block containing `operator new` and we get:
```
_43 = __bytes_42 + 7;
__max_44 = _43 & 4294967288;
__max.0_45 = (signed int) __max_44;
_46 = __max.0_45 >> 31;
_47 = (unsigned int) _46;
_61 = __max_44 - __bytes_42;
__spare_49 = _47 + _61;
if (__spare_49 > 3)
goto <bb 5>; [50.00%]
else
goto <bb 4>; [50.00%]
<bb 4> [local count: 483183820]:
_20 = operator new (__bytes_42);
goto <bb 6>; [100.00%]
<bb 5> [local count: 483183820]:
__n_50 = _18 + 1;
__bytes_51 = __bytes_42 + 4;
_35 = operator new (__bytes_51);
_12 = MIN_EXPR <__n_50, 536870911>;
_67 = _12 * 4;
<bb 6> [local count: 966367642]:
# _32 = PHI <_20(4), _35(5)>
# prephitmp_2 = PHI <__bytes_42(4), _67(5)>
operator delete (_32, prephitmp_2);
```
While we don't re-commonialize the `operator new` here. The way dce works for
deleting operator delete/new pairs is only requires a pair so in this case we
have 2 operator new for the operator delete and that gets confused.
