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Re-add getBudgetOverride() but also account for path length of

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overridden
This commit is contained in:
Eddie Hung 2018-07-26 22:32:24 -07:00
parent d083451cd5
commit 69ef533db3
1 changed files with 18 additions and 6 deletions
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24
common/timing.cc
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@ -83,8 +83,15 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t s
auto &usr = net->users[i]; auto &usr = net->users[i];
if (crit_path) if (crit_path)
current_path->push_back(&usr); 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, 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)); updates, min_slack, current_path, crit_path));
if (crit_path) if (crit_path)
current_path->pop_back(); current_path->pop_back();
@ -136,10 +143,13 @@ void assign_budget(Context *ctx)
UpdateMap updates; UpdateMap updates;
delay_t min_slack = compute_min_slack(ctx, &updates, nullptr); delay_t min_slack = compute_min_slack(ctx, &updates, nullptr);
// If user has not specified a frequency, adjust the target frequency // If user has not specified a frequency, adjust the target frequency dynamically
// to be equivalent to the estimate Fmax // TODO(eddieh): Tune these factors
if (!ctx->user_freq) { 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) if (ctx->verbose)
log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack, log_info("minimum slack for this assign = %d, target Fmax for next update = %.2f MHz\n", min_slack,
ctx->target_freq / 1e6); ctx->target_freq / 1e6);
@ -153,7 +163,8 @@ void assign_budget(Context *ctx)
auto it = updates.find(pi); auto it = updates.find(pi);
if (it == updates.end()) if (it == updates.end())
continue; 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 // Post-update check
if (ctx->user_freq && user.budget < 0) if (ctx->user_freq && user.budget < 0)
@ -185,7 +196,8 @@ void update_budget(Context *ctx)
auto it = updates.find(pi); auto it = updates.find(pi);
if (it == updates.end()) if (it == updates.end())
continue; 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 // Post-update check
if (ctx->verbose) { if (ctx->verbose) {