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Refactor

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This commit is contained in:
Eddie Hung 2018-07-28 12:50:21 -07:00
parent 0be236ce05
commit e0517caf1a
4 changed files with 24 additions and 46 deletions
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2
common/placer1.cc
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@ -275,7 +275,7 @@ class SAPlacer
} }
} }
} }
compute_fmax(ctx, true /* print_fmax */); timing_analysis(ctx, true /* print_fmax */);
ctx->unlock(); ctx->unlock();
return true; return true;
} }

2
common/router1.cc
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@ -814,7 +814,7 @@ bool router1(Context *ctx)
#ifndef NDEBUG #ifndef NDEBUG
ctx->check(); ctx->check();
#endif #endif
compute_fmax(ctx, true /* print_fmax */, true /* print_path */); timing_analysis(ctx, true /* print_fmax */, true /* print_path */);
ctx->unlock(); ctx->unlock();
return true; return true;
} catch (log_execution_error_exception) { } catch (log_execution_error_exception) {

62
common/timing.cc
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@ -26,14 +26,13 @@
NEXTPNR_NAMESPACE_BEGIN NEXTPNR_NAMESPACE_BEGIN
typedef std::unordered_map<const PortInfo *, delay_t> UpdateMap;
typedef std::list<const PortRef *> PortRefList; typedef std::list<const PortRef *> PortRefList;
static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, UpdateMap *updates, static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path); delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path);
// Follow a path, returning budget to annotate // Follow a path, returning budget to annotate
static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, delay_t slack, UpdateMap *updates, static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path) delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path)
{ {
delay_t value; delay_t value;
@ -58,7 +57,7 @@ static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, de
if (is_path) { if (is_path) {
NetInfo *net = port.second.net; NetInfo *net = port.second.net;
if (net) { if (net) {
delay_t path_budget = follow_net(ctx, net, path_length, slack - comb_delay, updates, min_slack, delay_t path_budget = follow_net(ctx, net, path_length, slack - comb_delay, update, min_slack,
current_path, crit_path); current_path, crit_path);
value = std::min(value, path_budget); value = std::min(value, path_budget);
} }
@ -66,16 +65,10 @@ static delay_t follow_user_port(Context *ctx, PortRef &user, int path_length, de
} }
} }
} }
if (updates) {
auto ret = updates->emplace(&user.cell->ports.at(user.port), value);
if (!ret.second)
ret.first->second = std::min(value, ret.first->second);
}
return value; return value;
} }
static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, UpdateMap *updates, static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t slack, bool update,
delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path) delay_t &min_slack, PortRefList *current_path, PortRefList *crit_path)
{ {
delay_t net_budget = slack / (path_length + 1); delay_t net_budget = slack / (path_length + 1);
@ -92,14 +85,16 @@ static delay_t follow_net(Context *ctx, NetInfo *net, int path_length, delay_t s
} }
net_budget = std::min(net_budget, net_budget = std::min(net_budget,
follow_user_port(ctx, usr, pl, slack - ctx->getNetinfoRouteDelay(net, i), follow_user_port(ctx, usr, pl, slack - ctx->getNetinfoRouteDelay(net, i),
updates, min_slack, current_path, crit_path)); update, min_slack, current_path, crit_path));
if (update)
usr.budget = std::min(usr.budget, net_budget);
if (crit_path) if (crit_path)
current_path->pop_back(); current_path->pop_back();
} }
return net_budget; return net_budget;
} }
static delay_t compute_min_slack(Context *ctx, UpdateMap *updates, PortRefList *crit_path) static delay_t walk_paths(Context *ctx, bool update, PortRefList *crit_path)
{ {
delay_t default_slack = delay_t(1.0e12 / ctx->target_freq); delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
delay_t min_slack = default_slack; delay_t min_slack = default_slack;
@ -119,7 +114,7 @@ static delay_t compute_min_slack(Context *ctx, UpdateMap *updates, PortRefList *
if (ctx->getCellDelay(cell.second.get(), clock_domain, port.first, clkToQ)) if (ctx->getCellDelay(cell.second.get(), clock_domain, port.first, clkToQ))
slack -= clkToQ; slack -= clkToQ;
if (port.second.net) if (port.second.net)
follow_net(ctx, port.second.net, 0, slack, updates, min_slack, &current_path, crit_path); follow_net(ctx, port.second.net, 0, slack, update, min_slack, &current_path, crit_path);
} }
} }
} }
@ -140,20 +135,10 @@ void assign_budget(Context *ctx)
} }
} }
UpdateMap updates; delay_t min_slack = walk_paths(ctx, true, nullptr);
delay_t min_slack = compute_min_slack(ctx, &updates, nullptr);
// Update the budgets
for (auto &net : ctx->nets) { for (auto &net : ctx->nets) {
for (size_t i = 0; i < net.second->users.size(); ++i) { for (auto &user : net.second->users) {
auto &user = net.second->users[i];
auto pi = &user.cell->ports.at(user.port);
auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i);
auto it = updates.find(pi);
if (it != updates.end())
budget += 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)
log_warning("port %s.%s, connected to net '%s', has negative " log_warning("port %s.%s, connected to net '%s', has negative "
@ -185,22 +170,12 @@ void assign_budget(Context *ctx)
void update_budget(Context *ctx) void update_budget(Context *ctx)
{ {
UpdateMap updates; delay_t min_slack = walk_paths(ctx, true, nullptr);
delay_t min_slack = compute_min_slack(ctx, &updates, nullptr);
// Update the budgets if (ctx->verbose) {
for (auto &net : ctx->nets) { for (auto &net : ctx->nets) {
for (size_t i = 0; i < net.second->users.size(); ++i) { for (auto &user : net.second->users) {
auto &user = net.second->users[i]; // Post-update check
auto pi = &user.cell->ports.at(user.port);
auto budget = ctx->getNetinfoRouteDelay(net.second.get(), i);
auto it = updates.find(pi);
if (it != updates.end())
budget += it->second;
user.budget = ctx->getBudgetOverride(net.second.get(), i, budget);
// Post-update check
if (ctx->verbose) {
if (ctx->user_freq && user.budget < 0) if (ctx->user_freq && user.budget < 0)
log_warning("port %s.%s, connected to net '%s', has negative " log_warning("port %s.%s, connected to net '%s', has negative "
"timing budget of %fns\n", "timing budget of %fns\n",
@ -229,11 +204,11 @@ void update_budget(Context *ctx)
} }
} }
void compute_fmax(Context *ctx, bool print_fmax, bool print_path) delay_t timing_analysis(Context *ctx, bool print_fmax, bool print_path)
{ {
delay_t default_slack = delay_t(1.0e12 / ctx->target_freq); delay_t default_slack = delay_t(1.0e12 / ctx->target_freq);
PortRefList crit_path; PortRefList crit_path;
delay_t min_slack = compute_min_slack(ctx, nullptr, &crit_path); delay_t min_slack = walk_paths(ctx, false, &crit_path);
if (print_path) { if (print_path) {
delay_t total = 0; delay_t total = 0;
log_break(); log_break();
@ -271,6 +246,7 @@ void compute_fmax(Context *ctx, bool print_fmax, bool print_path)
} }
if (print_fmax) if (print_fmax)
log_info("estimated Fmax = %.2f MHz\n", 1e6 / (default_slack - min_slack)); log_info("estimated Fmax = %.2f MHz\n", 1e6 / (default_slack - min_slack));
return min_slack;
} }
NEXTPNR_NAMESPACE_END NEXTPNR_NAMESPACE_END

4
common/timing.h
View File

@ -30,7 +30,9 @@ void assign_budget(Context *ctx);
// Evenly redistribute the total path slack amongst all sinks on each path // Evenly redistribute the total path slack amongst all sinks on each path
void update_budget(Context *ctx); void update_budget(Context *ctx);
void compute_fmax(Context *ctx, bool print_fmax = false, bool print_path = false); // Perform timing analysis and return the minimum path slack,
// optionally, print out the fmax and critical path
delay_t timing_analysis(Context *ctx, bool print_fmax = false, bool print_path = false);
NEXTPNR_NAMESPACE_END NEXTPNR_NAMESPACE_END