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authorgatecat <gatecat@ds0.me>2022-04-08 13:42:54 +0100
committergatecat <gatecat@ds0.me>2022-04-08 13:42:54 +0100
commit49f178ed94b5fad00d25dbd12adea0bf4732f803 (patch)
treeea642e20bc07441a800944390e1f904e6ce5b113 /common/router2.cc
parente42e22575f20b59634f88b5cf694efdb413ff0a0 (diff)
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Split up common into kernel,place,route
Signed-off-by: gatecat <gatecat@ds0.me>
Diffstat (limited to 'common/router2.cc')
-rw-r--r--common/router2.cc1499
1 files changed, 0 insertions, 1499 deletions
diff --git a/common/router2.cc b/common/router2.cc
deleted file mode 100644
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--- a/common/router2.cc
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@@ -1,1499 +0,0 @@
-/*
- * 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