https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63949
--- Comment #7 from vekumar at gcc dot gnu.org ---
I ran GCC tests against the patch found one failure.
int
adds_shift_ext ( long long a, int b, int c)
{
long long d = (a + ((long long)b << 3));
if (d == 0)
return a + c;
else
return b + d + c;
}
The test expects adds generation and before my fix it is generated .
adds_shift_ext:
adds x3, x0, x1, sxtw 3 // 11 *adds_extvdi_multp2 [length
= 4]
beq .L5 // 12 *condjump [length = 4]
But now I am generating sign extends with shifts instead of sign extends with
mul in my patch.
adds_shift_ext:
add x3, x0, x1, sxtw 3 // 10 *add_extendsi_shft_di [length
= 4]
cbz x3, .L5 // 12 *cbeqdi1 [length = 4]
We don't have *adds_extendsi_shft_di pattern. We have patterns for
adds_extvdi_multp2 that extends an operation over mult.
Adding one will help optimize this case. But my concern is what if other
targets hits the same issue?
