/*
* convert slicing tree into actual floorplan
* returns the number of dead blocks compacted
*/
int tree_to_flp(tree_node_t *root, flp_t *flp, int compact_dead,
double compact_ratio)
{
/* for now, only choose the floorplan with
* the minimum area regardless of the overall
* aspect ratio
*/
int pos = min_area_pos(root->curve);
#if VERBOSE > 1
double compacted_area = 0.0;
#endif
int dead_count = recursive_sizing(root, pos, 0.0, 0.0, 0,
compact_dead, compact_ratio,
#if VERBOSE > 1
&compacted_area,
#endif
flp);
int compacted = (flp->n_units - 1) / 2 - dead_count;
flp->n_units -= compacted;
#if VERBOSE > 1
fprintf(stdout, "%d dead blocks, %.2f%% of the core compacted\n", compacted,
compacted_area / (get_total_area(flp)-compacted_area) * 100);
#endif
return compacted;
}
/* print the statistics about this floorplan.
* note that connects_file is NULL if wire
* information is already populated
*/
void print_flp_stats(flp_t *flp, RC_model_t *model,
char *l2_label, char *power_file,
char *connects_file)
{
double core, total, occupied; /* area */
double width, height, aspect, total_w, total_h;
double wire_metric;
double peak, avg; /* temperature */
double *power, *temp;
FILE *fp = NULL;
char str[STR_SIZE];
if (connects_file) {
fp = fopen(connects_file, "r");
if (!fp) {
sprintf(str, "error opening file %s\n", connects_file);
fatal(str);
}
flp_populate_connects(flp, fp);
}
power = hotspot_vector(model);
temp = hotspot_vector(model);
read_power(model, power, power_file);
core = get_core_area(flp, l2_label);
total = get_total_area(flp);
total_w = get_total_width(flp);
total_h = get_total_height(flp);
occupied = get_core_occupied_area(flp, l2_label);
width = get_core_width(flp, l2_label);
height = get_core_height(flp, l2_label);
aspect = (height > width) ? (height/width) : (width/height);
wire_metric = get_wire_metric(flp);
populate_R_model(model, flp);
steady_state_temp(model, power, temp);
peak = find_max_temp(model, temp);
avg = find_avg_temp(model, temp);
fprintf(stdout, "printing summary statistics about the floorplan\n");
fprintf(stdout, "total area:\t%g\n", total);
fprintf(stdout, "total width:\t%g\n", total_w);
fprintf(stdout, "total height:\t%g\n", total_h);
fprintf(stdout, "core area:\t%g\n", core);
fprintf(stdout, "occupied area:\t%g\n", occupied);
fprintf(stdout, "area utilization:\t%.3f\n", occupied / core * 100.0);
fprintf(stdout, "core width:\t%g\n", width);
fprintf(stdout, "core height:\t%g\n", height);
fprintf(stdout, "core aspect ratio:\t%.3f\n", aspect);
fprintf(stdout, "wire length metric:\t%.3f\n", wire_metric);
fprintf(stdout, "peak temperature:\t%.3f\n", peak);
fprintf(stdout, "avg temperature:\t%.3f\n", avg);
free_dvector(power);
free_dvector(temp);
if (fp)
fclose(fp);
}
/*
* this is the metric function used for the floorplanning.
* in order to enable a different metric, just change the
* return statement of this function to return an appropriate
* metric. The current metric used is a linear function of
* area (A), temperature (T) and wire length (W):
* lambdaA * A + lambdaT * T + lambdaW * W
* thermal model and power density are passed as parameters
* since temperature is used in the metric.
*/
double flp_evaluate_metric(flp_t *flp, RC_model_t *model, double *power,
double lambdaA, double lambdaT, double lambdaW)
{
double tmax, area, wire_length, width, height, aspect;
double *temp;
temp = hotspot_vector(model);
populate_R_model(model, flp);
steady_state_temp(model, power, temp);
tmax = find_max_temp(model, temp);
area = get_total_area(flp);
wire_length = get_wire_metric(flp);
width = get_total_width(flp);
height = get_total_height(flp);
if (width > height)
aspect = width / height;
else
aspect = height / width;
free_dvector(temp);
/* can return any arbitrary function of area, tmax and wire_length */
return (lambdaA * area + lambdaT * tmax + lambdaW * wire_length);
}
/*
* wrap the L2 around this floorplan. L2's area information
* is obtained from flp_desc. memory for L2 and its arms has
* already been allocated in the flp. note that flp & flp_desc
* have L2 hidden beyond the boundary at this point
*/
void flp_wrap_l2(flp_t *flp, flp_desc_t *flp_desc)
{
/*
* x is the width of the L2 arms
* y is the height of the bottom portion
*/
double x, y, core_width, core_height, total_side, core_area, l2_area;
unit_t *l2, *l2_left, *l2_right;
/* find L2 dimensions so that the total chip becomes a square */
core_area = get_total_area(flp);
core_width = get_total_width(flp);
core_height = get_total_height(flp);
/* flp_desc has L2 hidden beyond the boundary */
l2_area = flp_desc->units[flp_desc->n_units].area;
total_side = sqrt(core_area + l2_area);
/*
* width of the total chip after L2 wrapping is equal to
* the width of the core plus the width of the two arms
*/
x = (total_side - core_width) / 2.0;
y = total_side - core_height;
/*
* we are trying to solve the equation
* (2*x+core_width) * (y+core_height)
* = l2_area + core_area
* for x and y. it is possible that the values
* turnout to be negative if we restrict the
* total chip to be a square. in that case,
* theoretically, any value of x in the range
* (0, l2_area/(2*core_height)) and the
* corresponding value of y or any value of y
* in the range (0, l2_area/core_width) and the
* corresponding value of x would be a solution
* we look for a solution with a reasonable
* aspect ratio. i.e., we constrain kx = y (or
* ky = x depending on the aspect ratio of the
* core) where k = WRAP_L2_RATIO. solving the equation
* with this constraint, we get the following
*/
if ( x <= 0 || y <= 0.0) {
double sum;
if (core_width >= core_height) {
sum = WRAP_L2_RATIO * core_width + 2 * core_height;
x = (sqrt(sum*sum + 8*WRAP_L2_RATIO*l2_area) - sum) / (4*WRAP_L2_RATIO);
y = WRAP_L2_RATIO * x;
} else {
sum = core_width + 2 * WRAP_L2_RATIO * core_height;
y = (sqrt(sum*sum + 8*WRAP_L2_RATIO*l2_area) - sum) / (4*WRAP_L2_RATIO);
x = WRAP_L2_RATIO * y;
}
total_side = 2 * x + core_width;
}
/* fix the positions of core blocks */
flp_translate(flp, x, y);
/* restore the L2 blocks */
flp->n_units += (L2_ARMS+1);
/* copy L2 info again from flp_desc but from beyond the boundary */
copy_l2_info(flp, flp->n_units-L2_ARMS-1, flp_desc,
flp_desc->n_units, flp_desc->n_units);
/* fix the positions of the L2 blocks. connectivity
* information has already been fixed (in flp_placeholder).
* bottom L2 block - (leftx, bottomy) is already (0,0)
*/
l2 = &flp->units[flp->n_units-1-L2_ARMS];
l2->width = total_side;
l2->height = y;
l2->leftx = l2->bottomy = 0;
/* left L2 arm */
l2_left = &flp->units[flp->n_units-L2_ARMS+L2_LEFT];
l2_left->width = x;
l2_left->height = core_height;
l2_left->leftx = 0;
l2_left->bottomy = y;
/* right L2 arm */
l2_right = &flp->units[flp->n_units-L2_ARMS+L2_RIGHT];
l2_right->width = x;
l2_right->height = core_height;
l2_right->leftx = x + core_width;
l2_right->bottomy = y;
}