diff options
Diffstat (limited to 'common/timing.cc')
| -rw-r--r-- | common/timing.cc | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/common/timing.cc b/common/timing.cc index 7f28ef75..2873f017 100644 --- a/common/timing.cc +++ b/common/timing.cc @@ -83,8 +83,15 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t s auto &usr = net->users[i]; if (crit_path) current_path->push_back(&usr); + // If budget override is less than existing budget, then do not increment path length + int pl = path_length + 1; + auto budget = ctx->getBudgetOverride(net, i, net_budget); + if (budget < net_budget) { + net_budget = budget; + pl = std::max(1, path_length); + } net_budget = std::min(net_budget, - follow_user_port(ctx, usr, path_length + 1, slack - ctx->getNetinfoRouteDelay(net, i), + follow_user_port(ctx, usr, pl, slack - ctx->getNetinfoRouteDelay(net, i), updates, min_slack, current_path, crit_path)); if (crit_path) current_path->pop_back(); @@ -136,10 +143,13 @@ void assign_budget(Context *ctx) UpdateMap updates; delay_t min_slack = compute_min_slack(ctx, &updates, nullptr); - // If user has not specified a frequency, adjust the target frequency - // to be equivalent to the estimate Fmax + // If user has not specified a frequency, adjust the target frequency dynamically + // TODO(eddieh): Tune these factors if (!ctx->user_freq) { - ctx->target_freq = 1e12 / (default_slack - min_slack); + if (min_slack < 0) + ctx->target_freq = 1e12 / (default_slack - 0.95 * min_slack); + else + ctx->target_freq = 1e12 / (default_slack - 1.2 * min_slack); if (ctx->verbose) log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack, ctx->target_freq / 1e6); @@ -153,7 +163,8 @@ void assign_budget(Context *ctx) auto it = updates.find(pi); if (it == updates.end()) continue; - user.budget = ctx->getNetinfoRouteDelay(net.second.get(), i) - it->second; + auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i) - it->second; + user.budget = ctx->getBudgetOverride(net.second.get(), i, budget); // Post-update check if (ctx->user_freq && user.budget < 0) @@ -185,7 +196,8 @@ void update_budget(Context *ctx) auto it = updates.find(pi); if (it == updates.end()) continue; - user.budget = ctx->getNetinfoRouteDelay(net.second.get(), i) - it->second; + auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i) - it->second; + user.budget = ctx->getBudgetOverride(net.second.get(), i, budget); // Post-update check if (ctx->verbose) { |