[Bug middle-end/99638] s132 and s281 benchmarks of TSVC on zen3 benefits from -mno-fma

[hubicka at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99638

Jan Hubicka <hubicka at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jamborm at gcc dot gnu.org
            Summary|s132 benchmarks of TSVC on  |s132 and s281 benchmarks of
                   |zen3 benefits from -mno-fma |TSVC on zen3 benefits from
                   |                            |-mno-fma

--- Comment #1 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
s281 benchmark:

typedef float real_t;

#define iterations 1000000
#define LEN_1D 32000
#define LEN_2D 256
// array definitions
real_t flat_2d_array[LEN_2D*LEN_2D];

real_t x[LEN_1D];

real_t a[LEN_1D],b[LEN_1D],c[LEN_1D],d[LEN_1D],e[LEN_1D],
aa[LEN_2D][LEN_2D],bb[LEN_2D][LEN_2D],cc[LEN_2D][LEN_2D],tt[LEN_2D][LEN_2D];

int indx[LEN_1D];

real_t* __restrict__ xx;
real_t* yy;

// %2.5

void main()
{
//    crossing thresholds
//    index set splitting
//    reverse data access

    real_t x;
    for (int nl = 0; nl < iterations; nl++) {
        for (int i = 0; i < LEN_1D; i++) {
            x = a[LEN_1D-i-1] + b[i] * c[i];
            a[i] = x-(real_t)1.0;
            b[i] = x;
        }
        dummy();
    }
}


with FMA runs 18s and without 14s