[Bug c/112432] Internal-fn: The [i|l|ll]rint family don't support FLOATN

[pan2.li at intel dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112432

--- Comment #2 from Li Pan <pan2.li at intel dot com> ---
(In reply to Richard Biener from comment #1)
> Is there a corresponding C API?  We don't have "generic" versions in
> builtins.def either (with _VAR).
> 
> That said, what's the testcase here?

I found some FLOATN like api from glibc doc, when given N is 16.

long int lrintfN (_FloatN x);
long int lroundfN (_FloatN x);

https://www.gnu.org/software/libc/manual/2.38/html_mono/libc.html

The context comes from the autovec for the lrintf and lrintf16. For example as
below

void
test_lrintf16 (long *out, _Float16 *in, unsigned count)
{
  for (unsigned i = 0; i < count; i++)
    out[i] = __builtin_lrintf16 (in[i]);
}

void
test_lrintf (long *out, float *in, unsigned count)
{
  for (unsigned i = 0; i < count; i++)
    out[i] = __builtin_lrintf (in[i]);
}

We may have similar rtl code when compile with "-march=rv64gcv_zvfh_zfh
-mabi=lp64d -O3 -ftree-vectorize -ffast-math".
void
test_lrintf16 (long *out, _Float16 *in, unsigned count)
{
  # ivtmp.8_28 = PHI <ivtmp.8_27(4), ivtmp.8_26(3)>                             
  # ivtmp.9_25 = PHI <ivtmp.9_24(4), ivtmp.9_23(3)>
  _22 = (void *) ivtmp.8_28;
  _4 = MEM[(_Float16 *)_22];
  _7 = __builtin_lrintf16 (_4);
  _21 = (void *) ivtmp.9_25;
  MEM[(long int *)_21] = _7;
  ivtmp.8_27 = ivtmp.8_28 + 2;
  ivtmp.9_24 = ivtmp.9_25 + 8;
}

void
test_lrintf (long *out, float *in, unsigned count)
{
  # ivtmp.37_32 = PHI <ivtmp.37_48(5), ivtmp.37_28(4)>
  # ivtmp.40_26 = PHI <ivtmp.40_25(5), ivtmp.40_24(4)>
  _23 = (void *) ivtmp.37_32;
  vect__4.21_40 = MEM <vector(16) float> [(float *)_23];
  vect__7.22_41 = .LRINT (vect__4.21_40);                 // Expand lrint<m><n>
  _22 = (void *) ivtmp.40_26;
  MEM <vector(16) long int> [(long int *)_22] = vect__7.22_41;
  ivtmp.37_48 = ivtmp.37_32 + 64;
  ivtmp.40_25 = ivtmp.40_26 + 128;
}