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Diffstat (limited to 'common/route/router2.cc')
-rw-r--r-- | common/route/router2.cc | 1499 |
1 files changed, 1499 insertions, 0 deletions
diff --git a/common/route/router2.cc b/common/route/router2.cc new file mode 100644 index 00000000..e943e493 --- /dev/null +++ b/common/route/router2.cc @@ -0,0 +1,1499 @@ +/* + * nextpnr -- Next Generation Place and Route + * + * Copyright (C) 2019 gatecat <gatecat@ds0.me> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + * Core routing algorithm based on CRoute: + * + * CRoute: A Fast High-quality Timing-driven Connection-based FPGA Router + * Dries Vercruyce, Elias Vansteenkiste and Dirk Stroobandt + * DOI 10.1109/FCCM.2019.00017 [PDF on SciHub] + * + * Modified for the nextpnr Arch API and data structures; optimised for + * real-world FPGA architectures in particular ECP5 and Xilinx UltraScale+ + * + */ + +#include "router2.h" + +#include <algorithm> +#include <boost/container/flat_map.hpp> +#include <chrono> +#include <deque> +#include <fstream> +#include <queue> + +#include "log.h" +#include "nextpnr.h" +#include "router1.h" +#include "scope_lock.h" +#include "timing.h" +#include "util.h" + +NEXTPNR_NAMESPACE_BEGIN + +namespace { +struct Router2 +{ + + struct PerArcData + { + WireId sink_wire; + ArcBounds bb; + bool routed = false; + }; + + // As we allow overlap at first; the nextpnr bind functions can't be used + // as the primary relation between arcs and wires/pips + struct PerNetData + { + WireId src_wire; + dict<WireId, std::pair<PipId, int>> wires; + std::vector<std::vector<PerArcData>> arcs; + ArcBounds bb; + // Coordinates of the center of the net, used for the weight-to-average + int cx, cy, hpwl; + int total_route_us = 0; + float max_crit = 0; + int fail_count = 0; + }; + + struct WireScore + { + float cost; + float togo_cost; + float total() const { return cost + togo_cost; } + }; + + struct PerWireData + { + // nextpnr + WireId w; + // Historical congestion cost + int curr_cong = 0; + float hist_cong_cost = 1.0; + // Wire is unavailable as locked to another arc + bool unavailable = false; + // This wire has to be used for this net + int reserved_net = -1; + // The notional location of the wire, to guarantee thread safety + int16_t x = 0, y = 0; + // Visit data + PipId pip_fwd, pip_bwd; + bool visited_fwd = false, visited_bwd = false; + }; + + Context *ctx; + Router2Cfg cfg; + + Router2(Context *ctx, const Router2Cfg &cfg) : ctx(ctx), cfg(cfg), tmg(ctx) { tmg.setup(); } + + // Use 'udata' for fast net lookups and indexing + std::vector<NetInfo *> nets_by_udata; + std::vector<PerNetData> nets; + + bool timing_driven, timing_driven_ripup; + TimingAnalyser tmg; + + void setup_nets() + { + // Populate per-net and per-arc structures at start of routing + nets.resize(ctx->nets.size()); + nets_by_udata.resize(ctx->nets.size()); + size_t i = 0; + for (auto &net : ctx->nets) { + NetInfo *ni = net.second.get(); + ni->udata = i; + nets_by_udata.at(i) = ni; + nets.at(i).arcs.resize(ni->users.capacity()); + + // Start net bounding box at overall min/max + nets.at(i).bb.x0 = std::numeric_limits<int>::max(); + nets.at(i).bb.x1 = std::numeric_limits<int>::min(); + nets.at(i).bb.y0 = std::numeric_limits<int>::max(); + nets.at(i).bb.y1 = std::numeric_limits<int>::min(); + nets.at(i).cx = 0; + nets.at(i).cy = 0; + + if (ni->driver.cell != nullptr) { + Loc drv_loc = ctx->getBelLocation(ni->driver.cell->bel); + nets.at(i).cx += drv_loc.x; + nets.at(i).cy += drv_loc.y; + } + + for (auto usr : ni->users.enumerate()) { + WireId src_wire = ctx->getNetinfoSourceWire(ni); + for (auto &dst_wire : ctx->getNetinfoSinkWires(ni, usr.value)) { + nets.at(i).src_wire = src_wire; + if (ni->driver.cell == nullptr) + src_wire = dst_wire; + if (ni->driver.cell == nullptr && dst_wire == WireId()) + continue; + if (src_wire == WireId()) + log_error("No wire found for port %s on source cell %s.\n", ctx->nameOf(ni->driver.port), + ctx->nameOf(ni->driver.cell)); + if (dst_wire == WireId()) + log_error("No wire found for port %s on destination cell %s.\n", ctx->nameOf(usr.value.port), + ctx->nameOf(usr.value.cell)); + nets.at(i).arcs.at(usr.index.idx()).emplace_back(); + auto &ad = nets.at(i).arcs.at(usr.index.idx()).back(); + ad.sink_wire = dst_wire; + // Set bounding box for this arc + ad.bb = ctx->getRouteBoundingBox(src_wire, dst_wire); + // Expand net bounding box to include this arc + nets.at(i).bb.x0 = std::min(nets.at(i).bb.x0, ad.bb.x0); + nets.at(i).bb.x1 = std::max(nets.at(i).bb.x1, ad.bb.x1); + nets.at(i).bb.y0 = std::min(nets.at(i).bb.y0, ad.bb.y0); + nets.at(i).bb.y1 = std::max(nets.at(i).bb.y1, ad.bb.y1); + } + // Add location to centroid sum + Loc usr_loc = ctx->getBelLocation(usr.value.cell->bel); + nets.at(i).cx += usr_loc.x; + nets.at(i).cy += usr_loc.y; + } + nets.at(i).hpwl = std::max( + std::abs(nets.at(i).bb.y1 - nets.at(i).bb.y0) + std::abs(nets.at(i).bb.x1 - nets.at(i).bb.x0), 1); + nets.at(i).cx /= int(ni->users.entries() + 1); + nets.at(i).cy /= int(ni->users.entries() + 1); + if (ctx->debug) + log_info("%s: bb=(%d, %d)->(%d, %d) c=(%d, %d) hpwl=%d\n", ctx->nameOf(ni), nets.at(i).bb.x0, + nets.at(i).bb.y0, nets.at(i).bb.x1, nets.at(i).bb.y1, nets.at(i).cx, nets.at(i).cy, + nets.at(i).hpwl); + nets.at(i).bb.x0 = std::max(nets.at(i).bb.x0 - cfg.bb_margin_x, 0); + nets.at(i).bb.y0 = std::max(nets.at(i).bb.y0 - cfg.bb_margin_y, 0); + nets.at(i).bb.x1 = std::min(nets.at(i).bb.x1 + cfg.bb_margin_x, ctx->getGridDimX()); + nets.at(i).bb.y1 = std::min(nets.at(i).bb.y1 + cfg.bb_margin_y, ctx->getGridDimY()); + i++; + } + } + + dict<WireId, int> wire_to_idx; + std::vector<PerWireData> flat_wires; + + PerWireData &wire_data(WireId w) { return flat_wires[wire_to_idx.at(w)]; } + + void setup_wires() + { + // Set up per-wire structures, so that MT parts don't have to do any memory allocation + // This is possibly quite wasteful and not cache-optimal; further consideration necessary + for (auto wire : ctx->getWires()) { + PerWireData pwd; + pwd.w = wire; + NetInfo *bound = ctx->getBoundWireNet(wire); + if (bound != nullptr) { + auto iter = bound->wires.find(wire); + if (iter != bound->wires.end()) { + auto &nd = nets.at(bound->udata); + nd.wires[wire] = std::make_pair(bound->wires.at(wire).pip, 0); + pwd.curr_cong = 1; + if (bound->wires.at(wire).strength == STRENGTH_PLACER) { + pwd.reserved_net = bound->udata; + } else if (bound->wires.at(wire).strength > STRENGTH_PLACER) { + pwd.unavailable = true; + } + } + } + + ArcBounds wire_loc = ctx->getRouteBoundingBox(wire, wire); + pwd.x = (wire_loc.x0 + wire_loc.x1) / 2; + pwd.y = (wire_loc.y0 + wire_loc.y1) / 2; + + wire_to_idx[wire] = int(flat_wires.size()); + flat_wires.push_back(pwd); + } + + for (auto &net_pair : ctx->nets) { + auto *net = net_pair.second.get(); + auto &nd = nets.at(net->udata); + for (auto usr : net->users.enumerate()) { + auto &ad = nd.arcs.at(usr.index.idx()); + for (size_t phys_pin = 0; phys_pin < ad.size(); phys_pin++) { + if (check_arc_routing(net, usr.index, phys_pin)) { + record_prerouted_net(net, usr.index, phys_pin); + } + } + } + } + } + + struct QueuedWire + { + + explicit QueuedWire(int wire = -1, WireScore score = WireScore{}, int randtag = 0) + : wire(wire), score(score), randtag(randtag){}; + + int wire; + WireScore score; + int randtag = 0; + + struct Greater + { + bool operator()(const QueuedWire &lhs, const QueuedWire &rhs) const noexcept + { + float lhs_score = lhs.score.cost + lhs.score.togo_cost, + rhs_score = rhs.score.cost + rhs.score.togo_cost; + return lhs_score == rhs_score ? lhs.randtag > rhs.randtag : lhs_score > rhs_score; + } + }; + }; + + bool hit_test_pip(ArcBounds &bb, Loc l) { return l.x >= bb.x0 && l.x <= bb.x1 && l.y >= bb.y0 && l.y <= bb.y1; } + + double curr_cong_weight, hist_cong_weight, estimate_weight; + + struct ThreadContext + { + // Nets to route + std::vector<NetInfo *> route_nets; + // Nets that failed routing + std::vector<NetInfo *> failed_nets; + + std::vector<std::pair<store_index<PortRef>, size_t>> route_arcs; + + std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> fwd_queue, bwd_queue; + // Special case where one net has multiple logical arcs to the same physical sink + pool<WireId> processed_sinks; + + std::vector<int> dirty_wires; + + // Thread bounding box + ArcBounds bb; + + DeterministicRNG rng; + + // Used to add existing routing to the heap + pool<WireId> in_wire_by_loc; + dict<std::pair<int, int>, pool<WireId>> wire_by_loc; + }; + + bool thread_test_wire(ThreadContext &t, PerWireData &w) + { + return w.x >= t.bb.x0 && w.x <= t.bb.x1 && w.y >= t.bb.y0 && w.y <= t.bb.y1; + } + + enum ArcRouteResult + { + ARC_SUCCESS, + ARC_RETRY_WITHOUT_BB, + ARC_FATAL, + }; + +// Define to make sure we don't print in a multithreaded context +#define ARC_LOG_ERR(...) \ + do { \ + if (is_mt) \ + return ARC_FATAL; \ + else \ + log_error(__VA_ARGS__); \ + } while (0) +#define ROUTE_LOG_DBG(...) \ + do { \ + if (!is_mt && ctx->debug) \ + log(__VA_ARGS__); \ + } while (0) + + void bind_pip_internal(PerNetData &net, store_index<PortRef> user, int wire, PipId pip) + { + auto &wd = flat_wires.at(wire); + auto found = net.wires.find(wd.w); + if (found == net.wires.end()) { + // Not yet used for any arcs of this net, add to list + net.wires.emplace(wd.w, std::make_pair(pip, 1)); + // Increase bound count of wire by 1 + ++wd.curr_cong; + } else { + // Already used for at least one other arc of this net + // Don't allow two uphill PIPs for the same net and wire + NPNR_ASSERT(found->second.first == pip); + // Increase the count of bound arcs + ++found->second.second; + } + } + + void unbind_pip_internal(PerNetData &net, store_index<PortRef> user, WireId wire) + { + auto &wd = wire_data(wire); + auto &b = net.wires.at(wd.w); + --b.second; + if (b.second == 0) { + // No remaining arcs of this net bound to this wire + --wd.curr_cong; + net.wires.erase(wd.w); + } + } + + void ripup_arc(NetInfo *net, store_index<PortRef> user, size_t phys_pin) + { + auto &nd = nets.at(net->udata); + auto &ad = nd.arcs.at(user.idx()).at(phys_pin); + if (!ad.routed) + return; + WireId src = nets.at(net->udata).src_wire; + WireId cursor = ad.sink_wire; + while (cursor != src) { + PipId pip = nd.wires.at(cursor).first; + unbind_pip_internal(nd, user, cursor); + cursor = ctx->getPipSrcWire(pip); + } + ad.routed = false; + } + + float score_wire_for_arc(NetInfo *net, store_index<PortRef> user, size_t phys_pin, WireId wire, PipId pip, + float crit_weight) + { + auto &wd = wire_data(wire); + auto &nd = nets.at(net->udata); + float base_cost = cfg.get_base_cost(ctx, wire, pip, crit_weight); + int overuse = wd.curr_cong; + float hist_cost = 1.0f + crit_weight * (wd.hist_cong_cost - 1.0f); + float bias_cost = 0; + int source_uses = 0; + if (nd.wires.count(wire)) { + overuse -= 1; + source_uses = nd.wires.at(wire).second; + } + float present_cost = 1.0f + overuse * curr_cong_weight * crit_weight; + if (pip != PipId()) { + Loc pl = ctx->getPipLocation(pip); + bias_cost = cfg.bias_cost_factor * (base_cost / int(net->users.entries())) * + ((std::abs(pl.x - nd.cx) + std::abs(pl.y - nd.cy)) / float(nd.hpwl)); + } + return base_cost * hist_cost * present_cost / (1 + (source_uses * crit_weight)) + bias_cost; + } + + float get_togo_cost(NetInfo *net, store_index<PortRef> user, int wire, WireId src_sink, float crit_weight, + bool bwd = false) + { + auto &nd = nets.at(net->udata); + auto &wd = flat_wires[wire]; + int source_uses = 0; + if (nd.wires.count(wd.w)) { + source_uses = nd.wires.at(wd.w).second; + } + // FIXME: timing/wirelength balance? + delay_t est_delay = ctx->estimateDelay(bwd ? src_sink : wd.w, bwd ? wd.w : src_sink); + return (ctx->getDelayNS(est_delay) / (1 + source_uses * crit_weight)) + cfg.ipin_cost_adder; + } + + bool check_arc_routing(NetInfo *net, store_index<PortRef> usr, size_t phys_pin) + { + auto &nd = nets.at(net->udata); + auto &ad = nd.arcs.at(usr.idx()).at(phys_pin); + WireId src_wire = nets.at(net->udata).src_wire; + WireId cursor = ad.sink_wire; + while (nd.wires.count(cursor)) { + auto &wd = wire_data(cursor); + if (wd.curr_cong != 1) + return false; + auto &uh = nd.wires.at(cursor).first; + if (uh == PipId()) + break; + cursor = ctx->getPipSrcWire(uh); + } + return (cursor == src_wire); + } + + void record_prerouted_net(NetInfo *net, store_index<PortRef> usr, size_t phys_pin) + { + auto &nd = nets.at(net->udata); + auto &ad = nd.arcs.at(usr.idx()).at(phys_pin); + ad.routed = true; + + WireId src = nets.at(net->udata).src_wire; + WireId cursor = ad.sink_wire; + while (cursor != src) { + size_t wire_idx = wire_to_idx.at(cursor); + PipId pip = nd.wires.at(cursor).first; + bind_pip_internal(nd, usr, wire_idx, pip); + cursor = ctx->getPipSrcWire(pip); + } + } + + // Returns true if a wire contains no source ports or driving pips + bool is_wire_undriveable(WireId wire, const NetInfo *net, int iter_count = 0) + { + // This is specifically designed to handle a particularly icky case that the current router struggles with in + // the nexus device, + // C -> C lut input only + // C; D; or F from another lut -> D lut input + // D or M -> M ff input + // without careful reservation of C for C lut input and D for D lut input, there is fighting for D between FF + // and LUT + if (iter_count > 7) + return false; // heuristic to assume we've hit general routing + if (wire_data(wire).unavailable) + return true; + if (wire_data(wire).reserved_net != -1 && wire_data(wire).reserved_net != net->udata) + return true; // reserved for another net + for (auto bp : ctx->getWireBelPins(wire)) + if ((net->driver.cell == nullptr || bp.bel == net->driver.cell->bel) && + ctx->getBelPinType(bp.bel, bp.pin) != PORT_IN) + return false; + for (auto p : ctx->getPipsUphill(wire)) + if (ctx->checkPipAvail(p)) { + if (!is_wire_undriveable(ctx->getPipSrcWire(p), net, iter_count + 1)) + return false; + } + return true; + } + + // Find all the wires that must be used to route a given arc + bool reserve_wires_for_arc(NetInfo *net, store_index<PortRef> i) + { + bool did_something = false; + WireId src = ctx->getNetinfoSourceWire(net); + auto &usr = net->users.at(i); + for (auto sink : ctx->getNetinfoSinkWires(net, usr)) { + pool<WireId> rsv; + WireId cursor = sink; + bool done = false; + if (ctx->debug) + log("reserving wires for arc %d (%s.%s) of net %s\n", i.idx(), ctx->nameOf(usr.cell), + ctx->nameOf(usr.port), ctx->nameOf(net)); + while (!done) { + auto &wd = wire_data(cursor); + if (ctx->debug) + log(" %s\n", ctx->nameOfWire(cursor)); + did_something |= (wd.reserved_net != net->udata); + if (wd.reserved_net != -1 && wd.reserved_net != net->udata) + log_error("attempting to reserve wire '%s' for nets '%s' and '%s'\n", ctx->nameOfWire(cursor), + ctx->nameOf(nets_by_udata.at(wd.reserved_net)), ctx->nameOf(net)); + wd.reserved_net = net->udata; + if (cursor == src) + break; + WireId next_cursor; + for (auto uh : ctx->getPipsUphill(cursor)) { + WireId w = ctx->getPipSrcWire(uh); + if (is_wire_undriveable(w, net)) + continue; + if (next_cursor != WireId()) { + done = true; + break; + } + next_cursor = w; + } + if (next_cursor == WireId()) + break; + cursor = next_cursor; + } + } + return did_something; + } + + void find_all_reserved_wires() + { + // Run iteratively, as reserving wires for one net might limit choices for another + bool did_something = false; + do { + did_something = false; + for (auto net : nets_by_udata) { + WireId src = ctx->getNetinfoSourceWire(net); + if (src == WireId()) + continue; + for (auto usr : net->users.enumerate()) + did_something |= reserve_wires_for_arc(net, usr.index); + } + } while (did_something); + } + + void reset_wires(ThreadContext &t) + { + for (auto w : t.dirty_wires) { + flat_wires[w].pip_fwd = PipId(); + flat_wires[w].pip_bwd = PipId(); + flat_wires[w].visited_fwd = false; + flat_wires[w].visited_bwd = false; + } + t.dirty_wires.clear(); + } + + // These nets have very-high-fanout pips and special rules must be followed (only working backwards) to avoid + // crippling perf + bool is_pseudo_const_net(const NetInfo *net) + { +#ifdef ARCH_NEXUS + if (net->driver.cell != nullptr && net->driver.cell->type == id_VCC_DRV) + return true; +#endif + return false; + } + + void update_wire_by_loc(ThreadContext &t, NetInfo *net, store_index<PortRef> i, size_t phys_pin, bool is_mt) + { + if (is_pseudo_const_net(net)) + return; + auto &nd = nets.at(net->udata); + auto &ad = nd.arcs.at(i.idx()).at(phys_pin); + WireId cursor = ad.sink_wire; + if (!nd.wires.count(cursor)) + return; + while (cursor != nd.src_wire) { + if (!t.in_wire_by_loc.count(cursor)) { + t.in_wire_by_loc.insert(cursor); + for (auto dh : ctx->getPipsDownhill(cursor)) { + Loc dh_loc = ctx->getPipLocation(dh); + t.wire_by_loc[std::make_pair(dh_loc.x, dh_loc.y)].insert(cursor); + } + } + cursor = ctx->getPipSrcWire(nd.wires.at(cursor).first); + } + } + + // Functions for marking wires as visited, and checking if they have already been visited + void set_visited_fwd(ThreadContext &t, int wire, PipId pip) + { + auto &wd = flat_wires.at(wire); + if (!wd.visited_fwd && !wd.visited_bwd) + t.dirty_wires.push_back(wire); + wd.pip_fwd = pip; + wd.visited_fwd = true; + } + void set_visited_bwd(ThreadContext &t, int wire, PipId pip) + { + auto &wd = flat_wires.at(wire); + if (!wd.visited_fwd && !wd.visited_bwd) + t.dirty_wires.push_back(wire); + wd.pip_bwd = pip; + wd.visited_bwd = true; + } + + bool was_visited_fwd(int wire) { return flat_wires.at(wire).visited_fwd; } + bool was_visited_bwd(int wire) { return flat_wires.at(wire).visited_bwd; } + + float get_arc_crit(NetInfo *net, store_index<PortRef> i) + { + if (!timing_driven) + return 0; + return tmg.get_criticality(CellPortKey(net->users.at(i))); + } + + bool arc_failed_slack(NetInfo *net, store_index<PortRef> usr_idx) + { + return timing_driven_ripup && + (tmg.get_setup_slack(CellPortKey(net->users.at(usr_idx))) < (2 * ctx->getDelayEpsilon())); + } + + ArcRouteResult route_arc(ThreadContext &t, NetInfo *net, store_index<PortRef> i, size_t phys_pin, bool is_mt, + bool is_bb = true) + { + // Do some initial lookups and checks + auto arc_start = std::chrono::high_resolution_clock::now(); + auto &nd = nets[net->udata]; + auto &ad = nd.arcs.at(i.idx()).at(phys_pin); + auto &usr = net->users.at(i); + ROUTE_LOG_DBG("Routing arc %d of net '%s' (%d, %d) -> (%d, %d)\n", i.idx(), ctx->nameOf(net), ad.bb.x0, + ad.bb.y0, ad.bb.x1, ad.bb.y1); + WireId src_wire = ctx->getNetinfoSourceWire(net), dst_wire = ctx->getNetinfoSinkWire(net, usr, phys_pin); + if (src_wire == WireId()) + ARC_LOG_ERR("No wire found for port %s on source cell %s.\n", ctx->nameOf(net->driver.port), + ctx->nameOf(net->driver.cell)); + if (dst_wire == WireId()) + ARC_LOG_ERR("No wire found for port %s on destination cell %s.\n", ctx->nameOf(usr.port), + ctx->nameOf(usr.cell)); + int src_wire_idx = wire_to_idx.at(src_wire); + int dst_wire_idx = wire_to_idx.at(dst_wire); + // Calculate a timing weight based on criticality + float crit = get_arc_crit(net, i); + float crit_weight = (1.0f - std::pow(crit, 2)); + ROUTE_LOG_DBG(" crit=%.3f crit_weight=%.3f\n", crit, crit_weight); + // Check if arc was already done _in this iteration_ + if (t.processed_sinks.count(dst_wire)) + return ARC_SUCCESS; + + // We have two modes: + // 0. starting within a small range of existing routing + // 1. expanding from all routing + int mode = 0; + if (net->users.entries() < 4 || nd.wires.empty() || (crit > 0.95)) + mode = 1; + + // This records the point where forwards and backwards routing met + int midpoint_wire = -1; + int explored = 1; + + for (; mode < 2; mode++) { + // Clear out the queues + if (!t.fwd_queue.empty()) { + std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> new_queue; + t.fwd_queue.swap(new_queue); + } + if (!t.bwd_queue.empty()) { + std::priority_queue<QueuedWire, std::vector<QueuedWire>, QueuedWire::Greater> new_queue; + t.bwd_queue.swap(new_queue); + } + // Unvisit any previously visited wires + reset_wires(t); + + ROUTE_LOG_DBG("src_wire = %s -> dst_wire = %s\n", ctx->nameOfWire(src_wire), ctx->nameOfWire(dst_wire)); + + // Add 'forward' direction startpoints to queue + auto seed_queue_fwd = [&](WireId wire, float wire_cost = 0) { + WireScore base_score; + base_score.cost = wire_cost; + int wire_idx = wire_to_idx.at(wire); + base_score.togo_cost = get_togo_cost(net, i, wire_idx, dst_wire, false, crit_weight); + t.fwd_queue.push(QueuedWire(wire_idx, base_score)); + set_visited_fwd(t, wire_idx, PipId()); + }; + auto &dst_data = flat_wires.at(dst_wire_idx); + // Look for nearby existing routing + for (int dy = -cfg.bb_margin_y; dy <= cfg.bb_margin_y; dy++) + for (int dx = -cfg.bb_margin_x; dx <= cfg.bb_margin_x; dx++) { + auto fnd = t.wire_by_loc.find(std::make_pair(dst_data.x + dx, dst_data.y + dy)); + if (fnd == t.wire_by_loc.end()) + continue; + for (WireId wire : fnd->second) { + ROUTE_LOG_DBG(" seeding with %s\n", ctx->nameOfWire(wire)); + seed_queue_fwd(wire); + } + } + + if (mode == 0 && t.fwd_queue.size() < 4) + continue; + + if (mode == 1 && !is_pseudo_const_net(net)) { + // Seed forwards with the source wire, if less than 8 existing wires added + seed_queue_fwd(src_wire); + } else { + set_visited_fwd(t, src_wire_idx, PipId()); + } + auto seed_queue_bwd = [&](WireId wire) { + WireScore base_score; + base_score.cost = 0; + int wire_idx = wire_to_idx.at(wire); + base_score.togo_cost = get_togo_cost(net, i, wire_idx, src_wire, true, crit_weight); + t.bwd_queue.push(QueuedWire(wire_idx, base_score)); + set_visited_bwd(t, wire_idx, PipId()); + }; + + // Seed backwards with the dest wire + seed_queue_bwd(dst_wire); + + int toexplore = 25000 * std::max(1, (ad.bb.x1 - ad.bb.x0) + (ad.bb.y1 - ad.bb.y0)); + int iter = 0; + + // Mode 0 required both queues to be live + while (((mode == 0) ? (!t.fwd_queue.empty() && !t.bwd_queue.empty()) + : (!t.fwd_queue.empty() || !t.bwd_queue.empty())) && + (!is_bb || iter < toexplore)) { + ++iter; + if (!t.fwd_queue.empty()) { + // Explore forwards + auto curr = t.fwd_queue.top(); + t.fwd_queue.pop(); + ++explored; + if (was_visited_bwd(curr.wire)) { + // Meet in the middle; done + midpoint_wire = curr.wire; + break; + } + auto &curr_data = flat_wires.at(curr.wire); + for (PipId dh : ctx->getPipsDownhill(curr_data.w)) { + // Skip pips outside of box in bounding-box mode + if (is_bb && !hit_test_pip(nd.bb, ctx->getPipLocation(dh))) + continue; + if (!ctx->checkPipAvailForNet(dh, net)) + continue; + WireId next = ctx->getPipDstWire(dh); + int next_idx = wire_to_idx.at(next); + if (was_visited_fwd(next_idx)) { + // Don't expand the same node twice. + continue; + } + auto &nwd = flat_wires.at(next_idx); + if (nwd.unavailable) + continue; + // Reserved for another net + if (nwd.reserved_net != -1 && nwd.reserved_net != net->udata) + continue; + // Don't allow the same wire to be bound to the same net with a different driving pip + auto fnd_wire = nd.wires.find(next); + if (fnd_wire != nd.wires.end() && fnd_wire->second.first != dh) + continue; + if (!thread_test_wire(t, nwd)) + continue; // thread safety issue + WireScore next_score; + next_score.cost = curr.score.cost + score_wire_for_arc(net, i, phys_pin, next, dh, crit_weight); + next_score.togo_cost = + cfg.estimate_weight * get_togo_cost(net, i, next_idx, dst_wire, false, crit_weight); + set_visited_fwd(t, next_idx, dh); + t.fwd_queue.push(QueuedWire(next_idx, next_score, t.rng.rng())); + } + } + if (!t.bwd_queue.empty()) { + // Explore backwards + auto curr = t.bwd_queue.top(); + t.bwd_queue.pop(); + ++explored; + if (was_visited_fwd(curr.wire)) { + // Meet in the middle; done + midpoint_wire = curr.wire; + break; + } + auto &curr_data = flat_wires.at(curr.wire); + // Don't allow the same wire to be bound to the same net with a different driving pip + PipId bound_pip; + auto fnd_wire = nd.wires.find(curr_data.w); + if (fnd_wire != nd.wires.end()) + bound_pip = fnd_wire->second.first; + + for (PipId uh : ctx->getPipsUphill(curr_data.w)) { + if (bound_pip != PipId() && bound_pip != uh) + continue; + if (is_bb && !hit_test_pip(nd.bb, ctx->getPipLocation(uh))) + continue; + if (!ctx->checkPipAvailForNet(uh, net)) + continue; + WireId next = ctx->getPipSrcWire(uh); + int next_idx = wire_to_idx.at(next); + if (was_visited_bwd(next_idx)) { + // Don't expand the same node twice. + continue; + } + auto &nwd = flat_wires.at(next_idx); + if (nwd.unavailable) + continue; + // Reserved for another net + if (nwd.reserved_net != -1 && nwd.reserved_net != net->udata) + continue; + if (!thread_test_wire(t, nwd)) + continue; // thread safety issue + WireScore next_score; + next_score.cost = curr.score.cost + score_wire_for_arc(net, i, phys_pin, next, uh, crit_weight); + next_score.togo_cost = + cfg.estimate_weight * get_togo_cost(net, i, next_idx, src_wire, true, crit_weight); + set_visited_bwd(t, next_idx, uh); + t.bwd_queue.push(QueuedWire(next_idx, next_score, t.rng.rng())); + } + } + } + if (midpoint_wire != -1) + break; + } + ArcRouteResult result = ARC_SUCCESS; + if (midpoint_wire != -1) { + ROUTE_LOG_DBG(" Routed (explored %d wires): ", explored); + int cursor_bwd = midpoint_wire; + while (was_visited_fwd(cursor_bwd)) { + PipId pip = flat_wires.at(cursor_bwd).pip_fwd; + if (pip == PipId() && cursor_bwd != src_wire_idx) + break; + bind_pip_internal(nd, i, cursor_bwd, pip); + if (ctx->debug && !is_mt) { + auto &wd = flat_wires.at(cursor_bwd); + ROUTE_LOG_DBG(" fwd wire: %s (curr %d hist %f share %d)\n", ctx->nameOfWire(wd.w), + wd.curr_cong - 1, wd.hist_cong_cost, nd.wires.at(wd.w).second); + } + if (pip == PipId()) { + break; + } + ROUTE_LOG_DBG(" fwd pip: %s (%d, %d)\n", ctx->nameOfPip(pip), ctx->getPipLocation(pip).x, + ctx->getPipLocation(pip).y); + cursor_bwd = wire_to_idx.at(ctx->getPipSrcWire(pip)); + } + + while (cursor_bwd != src_wire_idx) { + // Tack onto existing routing + WireId bwd_w = flat_wires.at(cursor_bwd).w; + if (!nd.wires.count(bwd_w)) + break; + auto &bound = nd.wires.at(bwd_w); + PipId pip = bound.first; + if (ctx->debug && !is_mt) { + auto &wd = flat_wires.at(cursor_bwd); + ROUTE_LOG_DBG(" ext wire: %s (curr %d hist %f share %d)\n", ctx->nameOfWire(wd.w), + wd.curr_cong - 1, wd.hist_cong_cost, bound.second); + } + bind_pip_internal(nd, i, cursor_bwd, pip); + if (pip == PipId()) + break; + cursor_bwd = wire_to_idx.at(ctx->getPipSrcWire(pip)); + } + + NPNR_ASSERT(cursor_bwd == src_wire_idx); + + int cursor_fwd = midpoint_wire; + while (was_visited_bwd(cursor_fwd)) { + PipId pip = flat_wires.at(cursor_fwd).pip_bwd; + if (pip == PipId()) { + break; + } + ROUTE_LOG_DBG(" bwd pip: %s (%d, %d)\n", ctx->nameOfPip(pip), ctx->getPipLocation(pip).x, + ctx->getPipLocation(pip).y); + cursor_fwd = wire_to_idx.at(ctx->getPipDstWire(pip)); + bind_pip_internal(nd, i, cursor_fwd, pip); + if (ctx->debug && !is_mt) { + auto &wd = flat_wires.at(cursor_fwd); + ROUTE_LOG_DBG(" bwd wire: %s (curr %d hist %f share %d)\n", ctx->nameOfWire(wd.w), + wd.curr_cong - 1, wd.hist_cong_cost, nd.wires.at(wd.w).second); + } + } + NPNR_ASSERT(cursor_fwd == dst_wire_idx); + + update_wire_by_loc(t, net, i, phys_pin, is_mt); + t.processed_sinks.insert(dst_wire); + ad.routed = true; + auto arc_end = std::chrono::high_resolution_clock::now(); + ROUTE_LOG_DBG("Routing arc %d of net '%s' (is_bb = %d) took %02fs\n", i.idx(), ctx->nameOf(net), is_bb, + std::chrono::duration<float>(arc_end - arc_start).count()); + } else { + auto arc_end = std::chrono::high_resolution_clock::now(); + ROUTE_LOG_DBG("Failed routing arc %d of net '%s' (is_bb = %d) took %02fs\n", i.idx(), ctx->nameOf(net), + is_bb, std::chrono::duration<float>(arc_end - arc_start).count()); + result = ARC_RETRY_WITHOUT_BB; + } + reset_wires(t); + return result; + } +#undef ARC_ERR + + bool route_net(ThreadContext &t, NetInfo *net, bool is_mt) + { + +#ifdef ARCH_ECP5 + if (net->is_global) + return true; +#endif + + ROUTE_LOG_DBG("Routing net '%s'...\n", ctx->nameOf(net)); + + auto rstart = std::chrono::high_resolution_clock::now(); + + // Nothing to do if net is undriven + if (net->driver.cell == nullptr) + return true; + + bool have_failures = false; + t.processed_sinks.clear(); + t.route_arcs.clear(); + t.wire_by_loc.clear(); + t.in_wire_by_loc.clear(); + auto &nd = nets.at(net->udata); + bool failed_slack = false; + for (auto usr : net->users.enumerate()) + failed_slack |= arc_failed_slack(net, usr.index); + for (auto usr : net->users.enumerate()) { + auto &ad = nd.arcs.at(usr.index.idx()); + for (size_t j = 0; j < ad.size(); j++) { + // Ripup failed arcs to start with + // Check if arc is already legally routed + if (!failed_slack && check_arc_routing(net, usr.index, j)) { + update_wire_by_loc(t, net, usr.index, j, true); + continue; + } + + // Ripup arc to start with + ripup_arc(net, usr.index, j); + t.route_arcs.emplace_back(usr.index, j); + } + } + // Route most critical arc first + std::stable_sort(t.route_arcs.begin(), t.route_arcs.end(), + [&](std::pair<store_index<PortRef>, size_t> a, std::pair<store_index<PortRef>, size_t> b) { + return get_arc_crit(net, a.first) > get_arc_crit(net, b.first); + }); + for (auto a : t.route_arcs) { + auto res1 = route_arc(t, net, a.first, a.second, is_mt, true); + if (res1 == ARC_FATAL) + return false; // Arc failed irrecoverably + else if (res1 == ARC_RETRY_WITHOUT_BB) { + if (is_mt) { + // Can't break out of bounding box in multi-threaded mode, so mark this arc as a failure + have_failures = true; + } else { + // Attempt a re-route without the bounding box constraint + ROUTE_LOG_DBG("Rerouting arc %d.%d of net '%s' without bounding box, possible tricky routing...\n", + a.first.idx(), int(a.second), ctx->nameOf(net)); + auto res2 = route_arc(t, net, a.first, a.second, is_mt, false); + // If this also fails, no choice but to give up + if (res2 != ARC_SUCCESS) { + if (ctx->debug) { + log_info("Pre-bound routing: \n"); + for (auto &wire_pair : net->wires) { + log(" %s", ctx->nameOfWire(wire_pair.first)); + if (wire_pair.second.pip != PipId()) + log(" %s", ctx->nameOfPip(wire_pair.second.pip)); + log("\n"); + } + } + log_error("Failed to route arc %d.%d of net '%s', from %s to %s.\n", a.first.idx(), + int(a.second), ctx->nameOf(net), ctx->nameOfWire(ctx->getNetinfoSourceWire(net)), + ctx->nameOfWire(ctx->getNetinfoSinkWire(net, net->users.at(a.first), a.second))); + } + } + } + } + if (cfg.perf_profile) { + auto rend = std::chrono::high_resolution_clock::now(); + nets.at(net->udata).total_route_us += + (std::chrono::duration_cast<std::chrono::microseconds>(rend - rstart).count()); + } + return !have_failures; + } +#undef ROUTE_LOG_DBG + + int total_wire_use = 0; + int overused_wires = 0; + int total_overuse = 0; + std::vector<int> route_queue; + std::set<int> failed_nets; + + void update_congestion() + { + total_overuse = 0; + overused_wires = 0; + total_wire_use = 0; + failed_nets.clear(); + pool<WireId> already_updated; + for (size_t i = 0; i < nets.size(); i++) { + auto &nd = nets.at(i); + for (const auto &w : nd.wires) { + ++total_wire_use; + auto &wd = wire_data(w.first); + if (wd.curr_cong > 1) { + if (already_updated.count(w.first)) { + ++total_overuse; + } else { + if (curr_cong_weight > 0) + wd.hist_cong_cost = + std::min(1e9, wd.hist_cong_cost + (wd.curr_cong - 1) * hist_cong_weight); + already_updated.insert(w.first); + ++overused_wires; + } + failed_nets.insert(i); + } + } + } + for (int n : failed_nets) { + auto &net_data = nets.at(n); + ++net_data.fail_count; + if ((net_data.fail_count % 3) == 0) { + // Every three times a net fails to route, expand the bounding box to increase the search space +#ifndef ARCH_MISTRAL + // This patch seems to make thing worse for CycloneV, as it slows down the resolution of TD congestion, + // disable it + net_data.bb.x0 = std::max(net_data.bb.x0 - 1, 0); + net_data.bb.y0 = std::max(net_data.bb.y0 - 1, 0); + net_data.bb.x1 = std::min(net_data.bb.x1 + 1, ctx->getGridDimX()); + net_data.bb.y1 = std::min(net_data.bb.y1 + 1, ctx->getGridDimY()); +#endif + } + } + } + + bool bind_and_check(NetInfo *net, store_index<PortRef> usr_idx, int phys_pin) + { +#ifdef ARCH_ECP5 + if (net->is_global) + return true; +#endif + bool success = true; + auto &nd = nets.at(net->udata); + auto &ad = nd.arcs.at(usr_idx.idx()).at(phys_pin); + auto &usr = net->users.at(usr_idx); + WireId src = ctx->getNetinfoSourceWire(net); + // Skip routes with no source + if (src == WireId()) + return true; + WireId dst = ctx->getNetinfoSinkWire(net, usr, phys_pin); + if (dst == WireId()) + return true; + + // Skip routes where there is no routing (special cases) + if (!ad.routed) { + if ((src == dst) && ctx->getBoundWireNet(dst) != net) + ctx->bindWire(src, net, STRENGTH_WEAK); + if (ctx->debug) { + log("Net %s not routed, not binding\n", ctx->nameOf(net)); + } + return true; + } + + WireId cursor = dst; + + std::vector<PipId> to_bind; + + while (cursor != src) { + if (!ctx->checkWireAvail(cursor)) { + NetInfo *bound_net = ctx->getBoundWireNet(cursor); + if (bound_net != net) { + if (ctx->verbose) { + if (bound_net != nullptr) { + log_info("Failed to bind wire %s to net %s, bound to net %s\n", ctx->nameOfWire(cursor), + net->name.c_str(ctx), bound_net->name.c_str(ctx)); + } else { + log_info("Failed to bind wire %s to net %s, bound net nullptr\n", ctx->nameOfWire(cursor), + net->name.c_str(ctx)); + } + } + success = false; + break; + } + } + if (!nd.wires.count(cursor)) { + log("Failure details:\n"); + log(" Cursor: %s\n", ctx->nameOfWire(cursor)); + log_error("Internal error; incomplete route tree for arc %d of net %s.\n", usr_idx.idx(), + ctx->nameOf(net)); + } + PipId p = nd.wires.at(cursor).first; + if (ctx->checkPipAvailForNet(p, net)) { + NetInfo *bound_net = ctx->getBoundPipNet(p); + if (bound_net == nullptr) { + to_bind.push_back(p); + } + } else { + if (ctx->verbose) { + log_info("Failed to bind pip %s to net %s\n", ctx->nameOfPip(p), net->name.c_str(ctx)); + } + success = false; + break; + } + cursor = ctx->getPipSrcWire(p); + } + + if (success) { + if (ctx->getBoundWireNet(src) == nullptr) + ctx->bindWire(src, net, STRENGTH_WEAK); + for (auto tb : to_bind) + ctx->bindPip(tb, net, STRENGTH_WEAK); + } else { + ripup_arc(net, usr_idx, phys_pin); + failed_nets.insert(net->udata); + } + return success; + } + + int arch_fail = 0; + bool bind_and_check_all() + { + // Make sure arch is internally consistent before we mess with it. + ctx->check(); + + bool success = true; + std::vector<WireId> net_wires; + for (auto net : nets_by_udata) { +#ifdef ARCH_ECP5 + if (net->is_global) + continue; +#endif + // Ripup wires and pips used by the net in nextpnr's structures + net_wires.clear(); + for (auto &w : net->wires) { + if (w.second.strength <= STRENGTH_STRONG) { + net_wires.push_back(w.first); + } else if (ctx->debug) { + log("Net %s didn't rip up wire %s because strength was %d\n", ctx->nameOf(net), + ctx->nameOfWire(w.first), w.second.strength); + } + } + for (auto w : net_wires) + ctx->unbindWire(w); + + if (ctx->debug) { + log("Ripped up %zu wires on net %s\n", net_wires.size(), ctx->nameOf(net)); + } + + // Bind the arcs using the routes we have discovered + for (auto usr : net->users.enumerate()) { + for (size_t phys_pin = 0; phys_pin < nets.at(net->udata).arcs.at(usr.index.idx()).size(); phys_pin++) { + if (!bind_and_check(net, usr.index, phys_pin)) { + ++arch_fail; + success = false; + } + } + } + } + + // Check that the arch is still internally consistent! + ctx->check(); + + return success; + } + + void write_wiretype_heatmap(std::ostream &out) + { + dict<IdString, std::vector<int>> cong_by_type; + size_t max_cong = 0; + // Build histogram + for (auto &wd : flat_wires) { + size_t val = wd.curr_cong; + IdString type = ctx->getWireType(wd.w); + max_cong = std::max(max_cong, val); + if (cong_by_type[type].size() <= max_cong) + cong_by_type[type].resize(max_cong + 1); + cong_by_type[type].at(val) += 1; + } + // Write csv + out << "type,"; + for (size_t i = 0; i <= max_cong; i++) + out << "bound=" << i << ","; + out << std::endl; + for (auto &ty : cong_by_type) { + out << ctx->nameOf(ty.first) << ","; + for (int count : ty.second) + out << count << ","; + out << std::endl; + } + } + + int mid_x = 0, mid_y = 0; + + void partition_nets() + { + // Create a histogram of positions in X and Y positions + std::map<int, int> cxs, cys; + for (auto &n : nets) { + if (n.cx != -1) + ++cxs[n.cx]; + if (n.cy != -1) + ++cys[n.cy]; + } + // 4-way split for now + int accum_x = 0, accum_y = 0; + int halfway = int(nets.size()) / 2; + for (auto &p : cxs) { + if (accum_x < halfway && (accum_x + p.second) >= halfway) + mid_x = p.first; + accum_x += p.second; + } + for (auto &p : cys) { + if (accum_y < halfway && (accum_y + p.second) >= halfway) + mid_y = p.first; + accum_y += p.second; + } + if (ctx->verbose) { + log_info(" x splitpoint: %d\n", mid_x); + log_info(" y splitpoint: %d\n", mid_y); + } + std::vector<int> bins(5, 0); + for (auto &n : nets) { + if (n.bb.x0 < mid_x && n.bb.x1 < mid_x && n.bb.y0 < mid_y && n.bb.y1 < mid_y) + ++bins[0]; // TL + else if (n.bb.x0 >= mid_x && n.bb.x1 >= mid_x && n.bb.y0 < mid_y && n.bb.y1 < mid_y) + ++bins[1]; // TR + else if (n.bb.x0 < mid_x && n.bb.x1 < mid_x && n.bb.y0 >= mid_y && n.bb.y1 >= mid_y) + ++bins[2]; // BL + else if (n.bb.x0 >= mid_x && n.bb.x1 >= mid_x && n.bb.y0 >= mid_y && n.bb.y1 >= mid_y) + ++bins[3]; // BR + else + ++bins[4]; // cross-boundary + } + if (ctx->verbose) + for (int i = 0; i < 5; i++) + log_info(" bin %d N=%d\n", i, bins[i]); + } + + void router_thread(ThreadContext &t, bool is_mt) + { + for (auto n : t.route_nets) { + bool result = route_net(t, n, is_mt); + if (!result) + t.failed_nets.push_back(n); + } + } + + void do_route() + { + // Don't multithread if fewer than 200 nets (heuristic) + if (route_queue.size() < 200) { + ThreadContext st; + st.rng.rngseed(ctx->rng64()); + st.bb = ArcBounds(0, 0, std::numeric_limits<int>::max(), std::numeric_limits<int>::max()); + for (size_t j = 0; j < route_queue.size(); j++) { + route_net(st, nets_by_udata[route_queue[j]], false); + } + return; + } + const int Nq = 4, Nv = 2, Nh = 2; + const int N = Nq + Nv + Nh; + std::vector<ThreadContext> tcs(N + 1); + for (auto &th : tcs) { + th.rng.rngseed(ctx->rng64()); + } + int le_x = mid_x; + int rs_x = mid_x; + int le_y = mid_y; + int rs_y = mid_y; + // Set up thread bounding boxes + tcs.at(0).bb = ArcBounds(0, 0, mid_x, mid_y); + tcs.at(1).bb = ArcBounds(mid_x + 1, 0, std::numeric_limits<int>::max(), le_y); + tcs.at(2).bb = ArcBounds(0, mid_y + 1, mid_x, std::numeric_limits<int>::max()); + tcs.at(3).bb = + ArcBounds(mid_x + 1, mid_y + 1, std::numeric_limits<int>::max(), std::numeric_limits<int>::max()); + + tcs.at(4).bb = ArcBounds(0, 0, std::numeric_limits<int>::max(), mid_y); + tcs.at(5).bb = ArcBounds(0, mid_y + 1, std::numeric_limits<int>::max(), std::numeric_limits<int>::max()); + + tcs.at(6).bb = ArcBounds(0, 0, mid_x, std::numeric_limits<int>::max()); + tcs.at(7).bb = ArcBounds(mid_x + 1, 0, std::numeric_limits<int>::max(), std::numeric_limits<int>::max()); + + tcs.at(8).bb = ArcBounds(0, 0, std::numeric_limits<int>::max(), std::numeric_limits<int>::max()); + + for (auto n : route_queue) { + auto &nd = nets.at(n); + auto ni = nets_by_udata.at(n); + int bin = N; + // Quadrants + if (nd.bb.x0 < le_x && nd.bb.x1 < le_x && nd.bb.y0 < le_y && nd.bb.y1 < le_y) + bin = 0; + else if (nd.bb.x0 >= rs_x && nd.bb.x1 >= rs_x && nd.bb.y0 < le_y && nd.bb.y1 < le_y) + bin = 1; + else if (nd.bb.x0 < le_x && nd.bb.x1 < le_x && nd.bb.y0 >= rs_y && nd.bb.y1 >= rs_y) + bin = 2; + else if (nd.bb.x0 >= rs_x && nd.bb.x1 >= rs_x && nd.bb.y0 >= rs_y && nd.bb.y1 >= rs_y) + bin = 3; + // Vertical split + else if (nd.bb.y0 < le_y && nd.bb.y1 < le_y) + bin = Nq + 0; + else if (nd.bb.y0 >= rs_y && nd.bb.y1 >= rs_y) + bin = Nq + 1; + // Horizontal split + else if (nd.bb.x0 < le_x && nd.bb.x1 < le_x) + bin = Nq + Nv + 0; + else if (nd.bb.x0 >= rs_x && nd.bb.x1 >= rs_x) + bin = Nq + Nv + 1; + tcs.at(bin).route_nets.push_back(ni); + } + if (ctx->verbose) + log_info("%d/%d nets not multi-threadable\n", int(tcs.at(N).route_nets.size()), int(route_queue.size())); +#ifdef NPNR_DISABLE_THREADS + // Singlethreaded routing - quadrants + for (int i = 0; i < Nq; i++) { + router_thread(tcs.at(i), /*is_mt=*/false); + } + // Vertical splits + for (int i = Nq; i < Nq + Nv; i++) { + router_thread(tcs.at(i), /*is_mt=*/false); + } + // Horizontal splits + for (int i = Nq + Nv; i < Nq + Nv + Nh; i++) { + router_thread(tcs.at(i), /*is_mt=*/false); + } +#else + // Multithreaded part of routing - quadrants + std::vector<boost::thread> threads; + for (int i = 0; i < Nq; i++) { + threads.emplace_back([this, &tcs, i]() { router_thread(tcs.at(i), /*is_mt=*/true); }); + } + for (auto &t : threads) + t.join(); + threads.clear(); + // Vertical splits + for (int i = Nq; i < Nq + Nv; i++) { + threads.emplace_back([this, &tcs, i]() { router_thread(tcs.at(i), /*is_mt=*/true); }); + } + for (auto &t : threads) + t.join(); + threads.clear(); + // Horizontal splits + for (int i = Nq + Nv; i < Nq + Nv + Nh; i++) { + threads.emplace_back([this, &tcs, i]() { router_thread(tcs.at(i), /*is_mt=*/true); }); + } + for (auto &t : threads) + t.join(); + threads.clear(); +#endif + // Singlethreaded part of routing - nets that cross partitions + // or don't fit within bounding box + for (auto st_net : tcs.at(N).route_nets) + route_net(tcs.at(N), st_net, false); + // Failed nets + for (int i = 0; i < N; i++) + for (auto fail : tcs.at(i).failed_nets) + route_net(tcs.at(N), fail, false); + } + + delay_t get_route_delay(int net, store_index<PortRef> usr_idx, int phys_idx) + { + auto &nd = nets.at(net); + auto &ad = nd.arcs.at(usr_idx.idx()).at(phys_idx); + WireId cursor = ad.sink_wire; + if (cursor == WireId() || nd.src_wire == WireId()) + return 0; + delay_t delay = 0; + while (true) { + delay += ctx->getWireDelay(cursor).maxDelay(); + if (!nd.wires.count(cursor)) + break; + auto &bound = nd.wires.at(cursor); + if (bound.first == PipId()) + break; + delay += ctx->getPipDelay(bound.first).maxDelay(); + cursor = ctx->getPipSrcWire(bound.first); + } + NPNR_ASSERT(cursor == nd.src_wire); + return delay; + } + + void update_route_delays() + { + for (int net : route_queue) { + NetInfo *ni = nets_by_udata.at(net); +#ifdef ARCH_ECP5 + if (ni->is_global) + continue; +#endif + auto &nd = nets.at(net); + for (auto usr : ni->users.enumerate()) { + delay_t arc_delay = 0; + for (int j = 0; j < int(nd.arcs.at(usr.index.idx()).size()); j++) + arc_delay = std::max(arc_delay, get_route_delay(net, usr.index, j)); + tmg.set_route_delay(CellPortKey(usr.value), DelayPair(arc_delay)); + } + } + } + + void operator()() + { + log_info("Running router2...\n"); + log_info("Setting up routing resources...\n"); + auto rstart = std::chrono::high_resolution_clock::now(); + setup_nets(); + setup_wires(); + find_all_reserved_wires(); + partition_nets(); + curr_cong_weight = cfg.init_curr_cong_weight; + hist_cong_weight = cfg.hist_cong_weight; + ThreadContext st; + int iter = 1; + + ScopeLock<Context> lock(ctx); + + for (size_t i = 0; i < nets_by_udata.size(); i++) + route_queue.push_back(i); + + timing_driven = ctx->setting<bool>("timing_driven"); + if (ctx->settings.count(ctx->id("router/tmg_ripup"))) + timing_driven_ripup = timing_driven && ctx->setting<bool>("router/tmg_ripup"); + else + timing_driven_ripup = false; + log_info("Running main router loop...\n"); + if (timing_driven) + tmg.run(true); + do { + ctx->sorted_shuffle(route_queue); + + if (timing_driven && int(route_queue.size()) >= 30) { + for (auto n : route_queue) { + NetInfo *ni = nets_by_udata.at(n); + auto &net = nets.at(n); + net.max_crit = 0; + for (auto &usr : ni->users) { + float c = tmg.get_criticality(CellPortKey(usr)); + net.max_crit = std::max(net.max_crit, c); + } + } + std::stable_sort(route_queue.begin(), route_queue.end(), + [&](int na, int nb) { return nets.at(na).max_crit > nets.at(nb).max_crit; }); + } + + do_route(); + update_route_delays(); + route_queue.clear(); + update_congestion(); + + if (!cfg.heatmap.empty()) { + std::string filename(cfg.heatmap + "_" + std::to_string(iter) + ".csv"); + std::ofstream cong_map(filename); + if (!cong_map) + log_error("Failed to open wiretype heatmap %s for writing.\n", filename.c_str()); + write_wiretype_heatmap(cong_map); + log_info(" wrote wiretype heatmap to %s.\n", filename.c_str()); + } + int tmgfail = 0; + if (timing_driven) + tmg.run(false); + if (timing_driven_ripup && iter < 500) { + for (size_t i = 0; i < nets_by_udata.size(); i++) { + NetInfo *ni = nets_by_udata.at(i); + for (auto usr : ni->users.enumerate()) { + if (arc_failed_slack(ni, usr.index)) { + failed_nets.insert(i); + ++tmgfail; + } + } + } + } + if (overused_wires == 0 && tmgfail == 0) { + // Try and actually bind nextpnr Arch API wires + bind_and_check_all(); + } + for (auto cn : failed_nets) + route_queue.push_back(cn); + if (timing_driven_ripup) + log_info(" iter=%d wires=%d overused=%d overuse=%d tmgfail=%d archfail=%s\n", iter, total_wire_use, + overused_wires, total_overuse, tmgfail, + (overused_wires > 0 || tmgfail > 0) ? "NA" : std::to_string(arch_fail).c_str()); + else + log_info(" iter=%d wires=%d overused=%d overuse=%d archfail=%s\n", iter, total_wire_use, + overused_wires, total_overuse, + (overused_wires > 0 || tmgfail > 0) ? "NA" : std::to_string(arch_fail).c_str()); + ++iter; + if (curr_cong_weight < 1e9) + curr_cong_weight += cfg.curr_cong_mult; + } while (!failed_nets.empty()); + if (cfg.perf_profile) { + std::vector<std::pair<int, IdString>> nets_by_runtime; + for (auto &n : nets_by_udata) { + nets_by_runtime.emplace_back(nets.at(n->udata).total_route_us, n->name); + } + std::sort(nets_by_runtime.begin(), nets_by_runtime.end(), std::greater<std::pair<int, IdString>>()); + log_info("1000 slowest nets by runtime:\n"); + for (int i = 0; i < std::min(int(nets_by_runtime.size()), 1000); i++) { + log(" %80s %6d %.1fms\n", nets_by_runtime.at(i).second.c_str(ctx), + int(ctx->nets.at(nets_by_runtime.at(i).second)->users.entries()), + nets_by_runtime.at(i).first / 1000.0); + } + } + auto rend = std::chrono::high_resolution_clock::now(); + log_info("Router2 time %.02fs\n", std::chrono::duration<float>(rend - rstart).count()); + + log_info("Running router1 to check that route is legal...\n"); + + lock.unlock_early(); + + router1(ctx, Router1Cfg(ctx)); + } +}; +} // namespace + +void router2(Context *ctx, const Router2Cfg &cfg) +{ + Router2 rt(ctx, cfg); + rt.ctx = ctx; + rt(); +} + +Router2Cfg::Router2Cfg(Context *ctx) +{ + backwards_max_iter = ctx->setting<int>("router2/bwdMaxIter", 20); + global_backwards_max_iter = ctx->setting<int>("router2/glbBwdMaxIter", 200); + bb_margin_x = ctx->setting<int>("router2/bbMargin/x", 3); + bb_margin_y = ctx->setting<int>("router2/bbMargin/y", 3); + ipin_cost_adder = ctx->setting<float>("router2/ipinCostAdder", 0.0f); + bias_cost_factor = ctx->setting<float>("router2/biasCostFactor", 0.25f); + init_curr_cong_weight = ctx->setting<float>("router2/initCurrCongWeight", 0.5f); + hist_cong_weight = ctx->setting<float>("router2/histCongWeight", 1.0f); + curr_cong_mult = ctx->setting<float>("router2/currCongWeightMult", 2.0f); + estimate_weight = ctx->setting<float>("router2/estimateWeight", 1.25f); + perf_profile = ctx->setting<bool>("router2/perfProfile", false); + if (ctx->settings.count(ctx->id("router2/heatmap"))) + heatmap = ctx->settings.at(ctx->id("router2/heatmap")).as_string(); + else + heatmap = ""; +} + +NEXTPNR_NAMESPACE_END |