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place_sa: Use int64_t for "wirelength" metric

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Signed-off-by: David Shah <davey1576@gmail.com>
This commit is contained in:
David Shah 2018-06-21 10:45:18 +02:00
parent 1df8a8b440
commit e526a4115b
1 changed files with 19 additions and 16 deletions
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31
common/place_sa.cc
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@ -41,6 +41,8 @@
NEXTPNR_NAMESPACE_BEGIN NEXTPNR_NAMESPACE_BEGIN
typedef int64_t wirelen_t;
class SAPlacer class SAPlacer
{ {
public: public:
@ -143,7 +145,7 @@ class SAPlacer
// Calculate wirelength after initial placement // Calculate wirelength after initial placement
curr_wirelength = 0; curr_wirelength = 0;
for (auto net : ctx->nets) { for (auto net : ctx->nets) {
float wl = get_wirelength(net.second); wirelen_t wl = get_wirelength(net.second);
wirelengths[net.first] = wl; wirelengths[net.first] = wl;
curr_wirelength += wl; curr_wirelength += wl;
} }
@ -159,7 +161,7 @@ class SAPlacer
if (iter % 5 == 0 || iter == 1) if (iter % 5 == 0 || iter == 1)
log_info(" at iteration #%d: temp = %f, wire length = %f\n", log_info(" at iteration #%d: temp = %f, wire length = %f\n",
iter, temp, curr_wirelength); iter, temp, double(curr_wirelength));
for (int m = 0; m < 15; ++m) { for (int m = 0; m < 15; ++m) {
// Loop through all automatically placed cells // Loop through all automatically placed cells
@ -182,7 +184,7 @@ class SAPlacer
if (iter % 5 != 0) if (iter % 5 != 0)
log_info( log_info(
" at iteration #%d: temp = %f, wire length = %f\n", " at iteration #%d: temp = %f, wire length = %f\n",
iter, temp, curr_wirelength); iter, temp, double(curr_wirelength));
break; break;
} }
@ -217,7 +219,7 @@ class SAPlacer
// accumulating over time // accumulating over time
curr_wirelength = 0; curr_wirelength = 0;
for (auto net : ctx->nets) { for (auto net : ctx->nets) {
float wl = get_wirelength(net.second); wirelen_t wl = get_wirelength(net.second);
wirelengths[net.first] = wl; wirelengths[net.first] = wl;
curr_wirelength += wl; curr_wirelength += wl;
} }
@ -304,9 +306,9 @@ class SAPlacer
} }
// Get the total estimated wirelength for a net // Get the total estimated wirelength for a net
float get_wirelength(NetInfo *net) wirelen_t get_wirelength(NetInfo *net)
{ {
float wirelength = 0; wirelen_t wirelength = 0;
int driver_x, driver_y; int driver_x, driver_y;
bool driver_gb; bool driver_gb;
CellInfo *driver_cell = net->driver.cell; CellInfo *driver_cell = net->driver.cell;
@ -331,10 +333,11 @@ class SAPlacer
// wirelength += std::abs(load_x - driver_x) + std::abs(load_y - // wirelength += std::abs(load_x - driver_x) + std::abs(load_y -
// driver_y); // driver_y);
delay_t raw_wl = ctx->estimateDelay(drv_wire, user_wire); delay_t raw_wl = ctx->estimateDelay(drv_wire, user_wire);
wirelength += pow(1.3, (ctx->getDelayNS(raw_wl) - wirelength += wirelen_t((pow(1.3, (ctx->getDelayNS(raw_wl) -
ctx->getDelayNS(load.budget)) / ctx->getDelayNS(load.budget)) /
10) + 10) +
ctx->getDelayNS(raw_wl); ctx->getDelayNS(raw_wl)) *
10);
// wirelength += pow(ctx->estimateDelay(drv_wire, user_wire), 2.0); // wirelength += pow(ctx->estimateDelay(drv_wire, user_wire), 2.0);
} }
return wirelength; return wirelength;
@ -344,13 +347,13 @@ class SAPlacer
bool try_swap_position(CellInfo *cell, BelId newBel) bool try_swap_position(CellInfo *cell, BelId newBel)
{ {
static std::unordered_set<NetInfo *> update; static std::unordered_set<NetInfo *> update;
static std::vector<std::pair<IdString, float>> new_lengths; static std::vector<std::pair<IdString, wirelen_t>> new_lengths;
new_lengths.clear(); new_lengths.clear();
update.clear(); update.clear();
BelId oldBel = cell->bel; BelId oldBel = cell->bel;
IdString other = ctx->getBelCell(newBel, true); IdString other = ctx->getBelCell(newBel, true);
CellInfo *other_cell = nullptr; CellInfo *other_cell = nullptr;
float new_wirelength = 0, delta; wirelen_t new_wirelength = 0, delta;
ctx->unbindBel(oldBel); ctx->unbindBel(oldBel);
if (other != IdString()) { if (other != IdString()) {
other_cell = ctx->cells[other]; other_cell = ctx->cells[other];
@ -390,7 +393,7 @@ class SAPlacer
// Recalculate wirelengths for all nets touched by the peturbation // Recalculate wirelengths for all nets touched by the peturbation
for (auto net : update) { for (auto net : update) {
new_wirelength -= wirelengths.at(net->name); new_wirelength -= wirelengths.at(net->name);
float net_new_wl = get_wirelength(net); wirelen_t net_new_wl = get_wirelength(net);
new_wirelength += net_new_wl; new_wirelength += net_new_wl;
new_lengths.push_back(std::make_pair(net->name, net_new_wl)); new_lengths.push_back(std::make_pair(net->name, net_new_wl));
} }
@ -400,7 +403,7 @@ class SAPlacer
if (delta < 0 || (temp > 1e-6 && (ctx->rng() / float(0x3fffffff)) <= if (delta < 0 || (temp > 1e-6 && (ctx->rng() / float(0x3fffffff)) <=
std::exp(-delta / temp))) { std::exp(-delta / temp))) {
n_accept++; n_accept++;
if (delta < 0) if (delta < 2)
improved = true; improved = true;
} else { } else {
if (other != IdString()) if (other != IdString())
@ -450,8 +453,8 @@ class SAPlacer
} }
Context *ctx; Context *ctx;
std::unordered_map<IdString, float> wirelengths; std::unordered_map<IdString, wirelen_t> wirelengths;
float curr_wirelength = std::numeric_limits<float>::infinity(); wirelen_t curr_wirelength = std::numeric_limits<wirelen_t>::max();
float temp = 1000; float temp = 1000;
bool improved = false; bool improved = false;
int n_move, n_accept; int n_move, n_accept;