re PR tree-optimization/48186 (ICE: SIGFPE (division by zero) in maybe_hot_frequency_p at predict.c:129 with --param hot-bb-frequency-fraction=0 on basic code)

        PR tree-optimization/48186
        * predict.c (maybe_hot_frequency_p): Return false if
        HOT_BB_FREQUENCY_FRACTION is 0.
        (cgraph_maybe_hot_edge_p): Likewise.

        * gcc.dg/pr48186.c: New test.

From-SVN: r197487