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common/placer1: In random pick, only use grid if there is more than 64 BELs

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If you have a large grid and very few BELs of a given type, picking a
random grid location yields very little odds of finding a BEL of that
type.

So for those, just put all of them at (0,0) and do a true random pick.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
This commit is contained in:
Sylvain Munaut 2018-11-17 19:19:32 +01:00
parent 1851ebb1c6
commit d6fd0e7e5b
2 changed files with 23 additions and 10 deletions
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32
common/placer1.cc
View File

@ -50,16 +50,21 @@ class SAPlacer
SAPlacer(Context *ctx, Placer1Cfg cfg) : ctx(ctx), cfg(cfg) SAPlacer(Context *ctx, Placer1Cfg cfg) : ctx(ctx), cfg(cfg)
{ {
int num_bel_types = 0; int num_bel_types = 0;
for (auto bel : ctx->getBels()) {
IdString type = ctx->getBelType(bel);
if (bel_types.find(type) == bel_types.end()) {
bel_types[type] = std::tuple<int, int>(num_bel_types++, 1);
} else {
std::get<1>(bel_types.at(type))++;
}
}
for (auto bel : ctx->getBels()) { for (auto bel : ctx->getBels()) {
Loc loc = ctx->getBelLocation(bel); Loc loc = ctx->getBelLocation(bel);
IdString type = ctx->getBelType(bel); IdString type = ctx->getBelType(bel);
int type_idx; int type_idx = std::get<0>(bel_types.at(type));
if (bel_types.find(type) == bel_types.end()) { int type_cnt = std::get<1>(bel_types.at(type));
type_idx = num_bel_types++; if (type_cnt < cfg.minBelsForGridPick)
bel_types[type] = type_idx; loc.x = loc.y = 0;
} else {
type_idx = bel_types.at(type);
}
if (int(fast_bels.size()) < type_idx + 1) if (int(fast_bels.size()) < type_idx + 1)
fast_bels.resize(type_idx + 1); fast_bels.resize(type_idx + 1);
if (int(fast_bels.at(type_idx).size()) < (loc.x + 1)) if (int(fast_bels.at(type_idx).size()) < (loc.x + 1))
@ -463,7 +468,10 @@ class SAPlacer
while (true) { while (true) {
int nx = ctx->rng(2 * diameter + 1) + std::max(curr_loc.x - diameter, 0); int nx = ctx->rng(2 * diameter + 1) + std::max(curr_loc.x - diameter, 0);
int ny = ctx->rng(2 * diameter + 1) + std::max(curr_loc.y - diameter, 0); int ny = ctx->rng(2 * diameter + 1) + std::max(curr_loc.y - diameter, 0);
int beltype_idx = bel_types.at(targetType); int beltype_idx, beltype_cnt;
std::tie(beltype_idx, beltype_cnt) = bel_types.at(targetType);
if (beltype_cnt < cfg.minBelsForGridPick)
nx = ny = 0;
if (nx >= int(fast_bels.at(beltype_idx).size())) if (nx >= int(fast_bels.at(beltype_idx).size()))
continue; continue;
if (ny >= int(fast_bels.at(beltype_idx).at(nx).size())) if (ny >= int(fast_bels.at(beltype_idx).at(nx).size()))
@ -485,7 +493,7 @@ class SAPlacer
bool improved = false; bool improved = false;
int n_move, n_accept; int n_move, n_accept;
int diameter = 35, max_x = 1, max_y = 1; int diameter = 35, max_x = 1, max_y = 1;
std::unordered_map<IdString, int> bel_types; std::unordered_map<IdString, std::tuple<int, int>> bel_types;
std::vector<std::vector<std::vector<std::vector<BelId>>>> fast_bels; std::vector<std::vector<std::vector<std::vector<BelId>>>> fast_bels;
std::unordered_set<BelId> locked_bels; std::unordered_set<BelId> locked_bels;
bool require_legal = true; bool require_legal = true;
@ -503,7 +511,11 @@ class SAPlacer
std::vector<decltype(NetInfo::udata)> old_udata; std::vector<decltype(NetInfo::udata)> old_udata;
}; };
Placer1Cfg::Placer1Cfg(Context *ctx) : Settings(ctx) { constraintWeight = get<float>("placer1/constraintWeight", 10); } Placer1Cfg::Placer1Cfg(Context *ctx) : Settings(ctx)
{
constraintWeight = get<float>("placer1/constraintWeight", 10);
minBelsForGridPick = get<int>("placer1/minBelsForGridPick", 64);
}
bool placer1(Context *ctx, Placer1Cfg cfg) bool placer1(Context *ctx, Placer1Cfg cfg)
{ {

1
common/placer1.h
View File

@ -28,6 +28,7 @@ struct Placer1Cfg : public Settings
{ {
Placer1Cfg(Context *ctx); Placer1Cfg(Context *ctx);
float constraintWeight; float constraintWeight;
int minBelsForGridPick;
}; };
extern bool placer1(Context *ctx, Placer1Cfg cfg); extern bool placer1(Context *ctx, Placer1Cfg cfg);