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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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35
common/place_sa.cc
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@ -41,6 +41,8 @@
NEXTPNR_NAMESPACE_BEGIN
typedef int64_t wirelen_t;
class SAPlacer
{
public:
@ -143,7 +145,7 @@ class SAPlacer
// Calculate wirelength after initial placement
curr_wirelength = 0;
for (auto net : ctx->nets) {
float wl = get_wirelength(net.second);
wirelen_t wl = get_wirelength(net.second);
wirelengths[net.first] = wl;
curr_wirelength += wl;
}
@ -159,7 +161,7 @@ class SAPlacer
if (iter % 5 == 0 || iter == 1)
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) {
// Loop through all automatically placed cells
@ -182,7 +184,7 @@ class SAPlacer
if (iter % 5 != 0)
log_info(
" at iteration #%d: temp = %f, wire length = %f\n",
iter, temp, curr_wirelength);
iter, temp, double(curr_wirelength));
break;
}
@ -217,7 +219,7 @@ class SAPlacer
// accumulating over time
curr_wirelength = 0;
for (auto net : ctx->nets) {
float wl = get_wirelength(net.second);
wirelen_t wl = get_wirelength(net.second);
wirelengths[net.first] = wl;
curr_wirelength += wl;
}
@ -304,9 +306,9 @@ class SAPlacer
}
// 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;
bool driver_gb;
CellInfo *driver_cell = net->driver.cell;
@ -331,10 +333,11 @@ class SAPlacer
// wirelength += std::abs(load_x - driver_x) + std::abs(load_y -
// driver_y);
delay_t raw_wl = ctx->estimateDelay(drv_wire, user_wire);
wirelength += pow(1.3, (ctx->getDelayNS(raw_wl) -
ctx->getDelayNS(load.budget)) /
10) +
ctx->getDelayNS(raw_wl);
wirelength += wirelen_t((pow(1.3, (ctx->getDelayNS(raw_wl) -
ctx->getDelayNS(load.budget)) /
10) +
ctx->getDelayNS(raw_wl)) *
10);
// wirelength += pow(ctx->estimateDelay(drv_wire, user_wire), 2.0);
}
return wirelength;
@ -344,13 +347,13 @@ class SAPlacer
bool try_swap_position(CellInfo *cell, BelId newBel)
{
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();
update.clear();
BelId oldBel = cell->bel;
IdString other = ctx->getBelCell(newBel, true);
CellInfo *other_cell = nullptr;
float new_wirelength = 0, delta;
wirelen_t new_wirelength = 0, delta;
ctx->unbindBel(oldBel);
if (other != IdString()) {
other_cell = ctx->cells[other];
@ -390,7 +393,7 @@ class SAPlacer
// Recalculate wirelengths for all nets touched by the peturbation
for (auto net : update) {
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_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)) <=
std::exp(-delta / temp))) {
n_accept++;
if (delta < 0)
if (delta < 2)
improved = true;
} else {
if (other != IdString())
@ -450,8 +453,8 @@ class SAPlacer
}
Context *ctx;
std::unordered_map<IdString, float> wirelengths;
float curr_wirelength = std::numeric_limits<float>::infinity();
std::unordered_map<IdString, wirelen_t> wirelengths;
wirelen_t curr_wirelength = std::numeric_limits<wirelen_t>::max();
float temp = 1000;
bool improved = false;
int n_move, n_accept;