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place: Reformat placer

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Signed-off-by: David Shah <davey1576@gmail.com>
This commit is contained in:
David Shah 2018-06-15 21:29:32 +02:00
parent 23b1fc02fb
commit 71903e29d4
1 changed files with 46 additions and 49 deletions
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95
common/place.cc
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@ -18,6 +18,7 @@
*/ */
#include "place.h" #include "place.h"
#include <algorithm>
#include <cmath> #include <cmath>
#include <iostream> #include <iostream>
#include <limits> #include <limits>
@ -25,14 +26,13 @@
#include <map> #include <map>
#include <ostream> #include <ostream>
#include <queue> #include <queue>
#include <random>
#include <set> #include <set>
#include <stdarg.h> #include <stdarg.h>
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <vector> #include <vector>
#include <random>
#include <algorithm>
#include "arch_place.h" #include "arch_place.h"
#include "log.h" #include "log.h"
@ -126,7 +126,8 @@ void place_design(Design *design)
} }
} }
struct rnd_state { struct rnd_state
{
uint32_t state; uint32_t state;
}; };
@ -142,12 +143,13 @@ static uint32_t xorshift32(rnd_state &rnd)
return x; return x;
} }
static float random_float_upto(rnd_state &rnd, float limit) { static float random_float_upto(rnd_state &rnd, float limit)
{
return xorshift32(rnd) / (4294967296 / limit); return xorshift32(rnd) / (4294967296 / limit);
} }
static int random_int_between(rnd_state &rnd, int a, int b)
static int random_int_between(rnd_state &rnd, int a, int b) { {
return a + int(random_float_upto(rnd, b - a)); return a + int(random_float_upto(rnd, b - a));
} }
@ -156,7 +158,7 @@ static void place_initial(Design *design, CellInfo *cell, rnd_state &rnd)
BelId best_bel = BelId(); BelId best_bel = BelId();
float best_score = std::numeric_limits<float>::infinity(); float best_score = std::numeric_limits<float>::infinity();
Chip &chip = design->chip; Chip &chip = design->chip;
if(cell->bel != BelId()) { if (cell->bel != BelId()) {
chip.unbindBel(cell->bel); chip.unbindBel(cell->bel);
cell->bel = BelId(); cell->bel = BelId();
} }
@ -182,7 +184,8 @@ static void place_initial(Design *design, CellInfo *cell, rnd_state &rnd)
cell->attrs["BEL"] = chip.getBelName(cell->bel).str(); cell->attrs["BEL"] = chip.getBelName(cell->bel).str();
} }
struct SAState { struct SAState
{
std::unordered_map<NetInfo *, float> wirelengths; std::unordered_map<NetInfo *, float> wirelengths;
float best_wirelength = std::numeric_limits<float>::infinity(); float best_wirelength = std::numeric_limits<float>::infinity();
float temp = 1000; float temp = 1000;
@ -192,7 +195,8 @@ struct SAState {
std::vector<std::vector<std::vector<std::vector<BelId>>>> fast_bels; std::vector<std::vector<std::vector<std::vector<BelId>>>> fast_bels;
}; };
static float get_wirelength(Chip *chip, NetInfo *net) { static float get_wirelength(Chip *chip, NetInfo *net)
{
float wirelength = 0; float wirelength = 0;
float driver_x = 0, driver_y = 0; float driver_x = 0, driver_y = 0;
bool consider_driver = false; bool consider_driver = false;
@ -201,7 +205,8 @@ static float get_wirelength(Chip *chip, NetInfo *net) {
return 0; return 0;
if (driver_cell->bel == BelId()) if (driver_cell->bel == BelId())
return 0; return 0;
consider_driver = chip->estimatePosition(driver_cell->bel, driver_x, driver_y); consider_driver =
chip->estimatePosition(driver_cell->bel, driver_x, driver_y);
if (!consider_driver) if (!consider_driver)
return 0; return 0;
for (auto load : net->users) { for (auto load : net->users) {
@ -217,7 +222,9 @@ static float get_wirelength(Chip *chip, NetInfo *net) {
return wirelength; return wirelength;
} }
static bool try_swap_position(Design *design, CellInfo *cell, BelId newBel, rnd_state &rnd, SAState &state) { static bool try_swap_position(Design *design, CellInfo *cell, BelId newBel,
rnd_state &rnd, SAState &state)
{
static std::unordered_set<NetInfo *> update; static std::unordered_set<NetInfo *> update;
static std::vector<std::pair<NetInfo *, float>> new_lengths; static std::vector<std::pair<NetInfo *, float>> new_lengths;
new_lengths.clear(); new_lengths.clear();
@ -271,7 +278,9 @@ static bool try_swap_position(Design *design, CellInfo *cell, BelId newBel, rnd_
delta = new_wirelength - state.best_wirelength; delta = new_wirelength - state.best_wirelength;
state.n_move++; state.n_move++;
if (delta < 0 || (state.temp > 1e-6 && random_float_upto(rnd, 1.0) <= std::exp(-delta/state.temp))) { if (delta < 0 ||
(state.temp > 1e-6 &&
random_float_upto(rnd, 1.0) <= std::exp(-delta / state.temp))) {
state.n_accept++; state.n_accept++;
if (delta < 0) if (delta < 0)
state.improved = true; state.improved = true;
@ -296,7 +305,8 @@ swap_fail:
return false; return false;
} }
BelId random_bel_for_cell(Design *design, CellInfo *cell, SAState& state, rnd_state &rnd) BelId random_bel_for_cell(Design *design, CellInfo *cell, SAState &state,
rnd_state &rnd)
{ {
BelId best_bel = BelId(); BelId best_bel = BelId();
Chip &chip = design->chip; Chip &chip = design->chip;
@ -305,8 +315,10 @@ BelId random_bel_for_cell(Design *design, CellInfo *cell, SAState& state, rnd_st
float x = 0, y = 0; float x = 0, y = 0;
chip.estimatePosition(cell->bel, x, y); chip.estimatePosition(cell->bel, x, y);
while (true) { while (true) {
int nx = random_int_between(rnd, std::max(int(x) - state.diameter, 0), int(x) + state.diameter + 1); int nx = random_int_between(rnd, std::max(int(x) - state.diameter, 0),
int ny = random_int_between(rnd, std::max(int(y) - state.diameter, 0), int(y) + state.diameter + 1); int(x) + state.diameter + 1);
int ny = random_int_between(rnd, std::max(int(y) - state.diameter, 0),
int(y) + state.diameter + 1);
if (nx >= state.fast_bels.at(int(targetType)).size()) if (nx >= state.fast_bels.at(int(targetType)).size())
continue; continue;
if (ny >= state.fast_bels.at(int(targetType)).at(nx).size()) if (ny >= state.fast_bels.at(int(targetType)).at(nx).size())
@ -369,11 +381,11 @@ void place_design_heuristic(Design *design)
float x, y; float x, y;
design->chip.estimatePosition(bel, x, y); design->chip.estimatePosition(bel, x, y);
BelType type = design->chip.getBelType(bel); BelType type = design->chip.getBelType(bel);
if (state.fast_bels.size() < int(type)+1) if (state.fast_bels.size() < int(type) + 1)
state.fast_bels.resize(int(type)+1); state.fast_bels.resize(int(type) + 1);
if (state.fast_bels.at(int(type)).size() < int(x)+1) if (state.fast_bels.at(int(type)).size() < int(x) + 1)
state.fast_bels.at(int(type)).resize(int(x) + 1); state.fast_bels.at(int(type)).resize(int(x) + 1);
if (state.fast_bels.at(int(type)).at(int(x)).size() < int(y)+1) if (state.fast_bels.at(int(type)).at(int(x)).size() < int(y) + 1)
state.fast_bels.at(int(type)).at(int(x)).resize(int(y) + 1); state.fast_bels.at(int(type)).at(int(x)).resize(int(y) + 1);
state.fast_bels.at(int(type)).at(int(x)).at(int((y))).push_back(bel); state.fast_bels.at(int(type)).at(int(x)).at(int((y))).push_back(bel);
} }
@ -388,31 +400,26 @@ void place_design_heuristic(Design *design)
int n_no_progress = 0; int n_no_progress = 0;
double avg_wirelength = state.best_wirelength; double avg_wirelength = state.best_wirelength;
state.temp = 10000; state.temp = 10000;
for (int iter=1;; iter++) for (int iter = 1;; iter++) {
{
state.n_move = state.n_accept = 0; state.n_move = state.n_accept = 0;
state.improved = false; state.improved = false;
//if (iter % 50 == 0) // if (iter % 50 == 0)
log(" at iteration #%d: temp = %f, wire length = %f\n", iter, state.temp, state.best_wirelength); log(" at iteration #%d: temp = %f, wire length = %f\n", iter,
state.temp, state.best_wirelength);
for (int m = 0; m < 15; ++m) for (int m = 0; m < 15; ++m) {
{ for (auto cell : autoplaced) {
for (auto cell : autoplaced)
{
BelId try_bel = random_bel_for_cell(design, cell, state, rnd); BelId try_bel = random_bel_for_cell(design, cell, state, rnd);
if (try_bel != BelId() && try_bel != cell->bel) if (try_bel != BelId() && try_bel != cell->bel)
try_swap_position(design, cell, try_bel, rnd, state); try_swap_position(design, cell, try_bel, rnd, state);
} }
} }
if (state.improved) if (state.improved) {
{
n_no_progress = 0; n_no_progress = 0;
// std::cout << "improved\n"; // std::cout << "improved\n";
} } else
else
++n_no_progress; ++n_no_progress;
if (state.temp <= 1e-3 && n_no_progress >= 5) if (state.temp <= 1e-3 && n_no_progress >= 5)
@ -420,33 +427,23 @@ void place_design_heuristic(Design *design)
double Raccept = (double)state.n_accept / (double)state.n_move; double Raccept = (double)state.n_accept / (double)state.n_move;
int M = 30; int M = 30;
double upper = 0.6, double upper = 0.6, lower = 0.4;
lower = 0.4;
if (state.best_wirelength < 0.95 * avg_wirelength) if (state.best_wirelength < 0.95 * avg_wirelength)
avg_wirelength = 0.8*avg_wirelength + 0.2 * state.best_wirelength; avg_wirelength = 0.8 * avg_wirelength + 0.2 * state.best_wirelength;
else else {
{ if (Raccept >= 0.8) {
if (Raccept >= 0.8)
{
state.temp *= 0.7; state.temp *= 0.7;
} } else if (Raccept > upper) {
else if (Raccept > upper)
{
if (state.diameter < M) if (state.diameter < M)
++state.diameter; ++state.diameter;
else else
state.temp *= 0.9; state.temp *= 0.9;
} } else if (Raccept > lower) {
else if (Raccept > lower)
{
state.temp *= 0.95; state.temp *= 0.95;
} } else {
else
{
// Raccept < 0.3 // Raccept < 0.3
if (state.diameter > 1) if (state.diameter > 1)
--state.diameter; --state.diameter;