1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
/*
* nextpnr -- Next Generation Place and Route
*
* Copyright (C) 2018 David Shah <david@symbioticeda.com>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#include "place_legaliser.h"
#include <algorithm>
#include <vector>
#include "cells.h"
#include "design_utils.h"
#include "log.h"
#include "util.h"
NEXTPNR_NAMESPACE_BEGIN
// Generic chain finder
template <typename F1, typename F2, typename F3>
std::vector<std::vector<CellInfo *>> find_chains(const Context *ctx, F1 cell_type_predicate, F2 get_previous,
F3 get_next, size_t min_length = 2)
{
std::set<IdString> chained;
std::vector<std::vector<CellInfo *>> chains;
for (auto cell : ctx->cells) {
if (chained.find(cell.first) != chained.end())
continue;
CellInfo *ci = cell.second;
if (cell_type_predicate(ctx, ci)) {
CellInfo *start = ci;
CellInfo *prev_start = ci;
while (prev_start != nullptr) {
start = prev_start;
prev_start = get_previous(ctx, start);
}
std::vector<CellInfo *> chain;
CellInfo *end = start;
while (end != nullptr) {
chain.push_back(end);
end = get_next(ctx, end);
}
if (chain.size() >= min_length) {
chains.push_back(chain);
for (auto c : chain)
chained.insert(c->name);
}
}
}
return chains;
};
bool legalise_design(Context *ctx)
{
std::vector<std::vector<CellInfo *>> carry_chains = find_chains(
ctx, is_lc,
[](const Context *ctx, const CellInfo *cell) {
return net_driven_by(ctx, cell->ports.at(ctx->id("CIN")).net, is_lc, ctx->id("COUT"));
},
[](const Context *ctx, const CellInfo *cell) {
return net_only_drives(ctx, cell->ports.at(ctx->id("COUT")).net, is_lc, ctx->id("CIN"), false);
});
// TODO
return true;
}
NEXTPNR_NAMESPACE_END
|