While analyzing code size regression in SPEC2k GCC binary I noticed that we perform some inline decisions because we think that number of executions are very high. In particular there was inline decision inlining gen_rtx_fmt_ee to find_reloads believing that it is called 4 billion times. This turned out to be cummulation of roundoff errors in propagate_freq which was bit mechanically updated from original sreals to C++ sreals and later to new probabilities. This led us to estimate that a loopback edge is reached with probability 2.3 which was capped to 1-1/10000 and since this happened in nested loop it quickly escalated to large values. Originally capping to REG_BR_PROB_BASE avoided such problems but now we have much higher range. This patch avoids going from probabilites to REG_BR_PROB_BASE so precision is kept. In addition it makes the propagation to not estimate more than param-max-predicted-loop-iterations. The first change makes the cap to not be triggered on the gcc build, but it is still better to be safe than sorry. * ipa-fnsummary.c (estimate_calls_size_and_time): Fix formating of dump. * params.opt: (max-predicted-iterations): Set bounds. * predict.c (real_almost_one, real_br_prob_base, real_inv_br_prob_base, real_one_half, real_bb_freq_max): Remove. (propagate_freq): Add max_cyclic_prob parameter; cap cyclic probabilities; do not truncate to reg_br_prob_bases. (estimate_loops_at_level): Pass max_cyclic_prob. (estimate_loops): Compute max_cyclic_prob. (estimate_bb_frequencies): Do not initialize real_*; update calculation of back edge prob. * profile-count.c (profile_probability::to_sreal): New. * profile-count.h (class sreal): Move up in file. (profile_probability::to_sreal): Declare.
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