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authorClifford Wolf <clifford@clifford.at>2014-07-18 16:46:40 +0200
committerClifford Wolf <clifford@clifford.at>2014-07-18 16:46:40 +0200
commite441f07d895a673c0bf40dcdc76781b50834fe44 (patch)
tree9d9bfcaa199aa911f602ac76822e98c88f55203c /passes/memory
parent44f13aff92146592fd9399bf96dfcb1f81fde708 (diff)
Added translation from read-feedback to en-signals in memory_share
Diffstat (limited to 'passes/memory')
-rw-r--r--passes/memory/memory.cc4
-rw-r--r--passes/memory/memory_share.cc246
2 files changed, 240 insertions, 10 deletions
diff --git a/passes/memory/memory.cc b/passes/memory/memory.cc
index a0c89a4d..fc309553 100644
--- a/passes/memory/memory.cc
+++ b/passes/memory/memory.cc
@@ -33,7 +33,9 @@ struct MemoryPass : public Pass {
log("This pass calls all the other memory_* passes in a useful order:\n");
log("\n");
log(" memory_dff\n");
+ log(" opt_clean\n");
log(" memory_share\n");
+ log(" opt_clean\n");
log(" memory_collect\n");
log(" memory_map (skipped if called with -nomap)\n");
log("\n");
@@ -59,7 +61,9 @@ struct MemoryPass : public Pass {
extra_args(args, argidx, design);
Pass::call(design, "memory_dff");
+ Pass::call(design, "opt_clean");
Pass::call(design, "memory_share");
+ Pass::call(design, "opt_clean");
Pass::call(design, "memory_collect");
if (!flag_nomap)
diff --git a/passes/memory/memory_share.cc b/passes/memory/memory_share.cc
index 140a4184..e2fa168c 100644
--- a/passes/memory/memory_share.cc
+++ b/passes/memory/memory_share.cc
@@ -36,7 +36,209 @@ struct MemoryShareWorker
{
RTLIL::Design *design;
RTLIL::Module *module;
- SigMap sigmap;
+ SigMap sigmap, sigmap_xmux;
+
+ std::map<RTLIL::SigBit, std::pair<RTLIL::Cell*, int>> sig_to_mux;
+ std::map<std::set<std::map<RTLIL::SigBit, bool>>, RTLIL::SigBit> conditions_logic_cache;
+
+
+ // -----------------------------------------------------------------
+ // Converting feedbacks to async read ports to proper enable signals
+ // -----------------------------------------------------------------
+
+ bool find_data_feedback(const std::set<RTLIL::SigBit> &async_rd_bits, RTLIL::SigBit sig,
+ std::map<RTLIL::SigBit, bool> &state, std::set<std::map<RTLIL::SigBit, bool>> &conditions)
+ {
+ if (async_rd_bits.count(sig)) {
+ conditions.insert(state);
+ return true;
+ }
+
+ if (sig_to_mux.count(sig) == 0)
+ return false;
+
+ RTLIL::Cell *cell = sig_to_mux.at(sig).first;
+ int bit_idx = sig_to_mux.at(sig).second;
+
+ std::vector<RTLIL::SigBit> sig_a = sigmap(cell->connections.at("\\A"));
+ std::vector<RTLIL::SigBit> sig_b = sigmap(cell->connections.at("\\B"));
+ std::vector<RTLIL::SigBit> sig_s = sigmap(cell->connections.at("\\S"));
+ std::vector<RTLIL::SigBit> sig_y = sigmap(cell->connections.at("\\Y"));
+ log_assert(sig_y.at(bit_idx) == sig);
+
+ for (int i = 0; i < int(sig_s.size()); i++)
+ if (state.count(sig_s[i]) && state.at(sig_s[i]) == true) {
+ if (find_data_feedback(async_rd_bits, sig_b.at(bit_idx + i*sig_y.size()), state, conditions))
+ cell->connections.at("\\B").replace(bit_idx + i*sig_y.size(), RTLIL::State::Sx);
+ return false;
+ }
+
+
+ for (int i = 0; i < int(sig_s.size()); i++)
+ {
+ if (state.count(sig_s[i]) && state.at(sig_s[i]) == false)
+ continue;
+
+ std::map<RTLIL::SigBit, bool> new_state = state;
+ new_state[sig_s[i]] = true;
+
+ if (find_data_feedback(async_rd_bits, sig_b.at(bit_idx + i*sig_y.size()), new_state, conditions))
+ cell->connections.at("\\B").replace(bit_idx + i*sig_y.size(), RTLIL::State::Sx);
+ }
+
+ std::map<RTLIL::SigBit, bool> new_state = state;
+ for (int i = 0; i < int(sig_s.size()); i++)
+ new_state[sig_s[i]] = false;
+
+ if (find_data_feedback(async_rd_bits, sig_a.at(bit_idx), new_state, conditions))
+ cell->connections.at("\\A").replace(bit_idx, RTLIL::State::Sx);
+
+ return false;
+ }
+
+ RTLIL::SigBit conditions_to_logic(std::set<std::map<RTLIL::SigBit, bool>> &conditions, int &created_conditions)
+ {
+ if (conditions_logic_cache.count(conditions))
+ return conditions_logic_cache.at(conditions);
+
+ RTLIL::SigSpec terms;
+ for (auto &cond : conditions) {
+ RTLIL::SigSpec sig1, sig2;
+ for (auto &it : cond) {
+ sig1.append_bit(it.first);
+ sig2.append_bit(it.second ? RTLIL::State::S1 : RTLIL::State::S0);
+ }
+ terms.append(module->Ne(NEW_ID, sig1, sig2));
+ created_conditions++;
+ }
+
+ if (terms.width > 1)
+ terms = module->ReduceAnd(NEW_ID, terms);
+
+ return conditions_logic_cache[conditions] = terms;
+ }
+
+ void translate_rd_feedback_to_en(std::string memid, std::vector<RTLIL::Cell*> &rd_ports, std::vector<RTLIL::Cell*> &wr_ports)
+ {
+ std::vector<std::set<RTLIL::SigBit>> async_rd_bits;
+ std::map<RTLIL::SigBit, std::set<RTLIL::SigBit>> muxtree_upstream_map;
+ std::set<RTLIL::SigBit> non_feedback_nets;
+
+ for (auto wire_it : module->wires)
+ if (wire_it.second->port_output) {
+ std::vector<RTLIL::SigBit> bits = RTLIL::SigSpec(wire_it.second);
+ non_feedback_nets.insert(bits.begin(), bits.end());
+ }
+
+ for (auto cell_it : module->cells)
+ {
+ RTLIL::Cell *cell = cell_it.second;
+ bool ignore_data_port = false;
+
+ if (cell->type == "$mux" || cell->type == "$pmux")
+ {
+ std::vector<RTLIL::SigBit> sig_a = sigmap(cell->connections.at("\\A"));
+ std::vector<RTLIL::SigBit> sig_b = sigmap(cell->connections.at("\\B"));
+ std::vector<RTLIL::SigBit> sig_s = sigmap(cell->connections.at("\\S"));
+ std::vector<RTLIL::SigBit> sig_y = sigmap(cell->connections.at("\\Y"));
+
+ non_feedback_nets.insert(sig_s.begin(), sig_s.end());
+
+ for (int i = 0; i < int(sig_y.size()); i++) {
+ muxtree_upstream_map[sig_y[i]].insert(sig_a[i]);
+ for (int j = 0; j < int(sig_s.size()); j++)
+ muxtree_upstream_map[sig_y[i]].insert(sig_b[i + j*sig_y.size()]);
+ }
+
+ continue;
+ }
+
+ if ((cell->type == "$memwr" || cell->type == "$memrd") &&
+ cell->parameters.at("\\MEMID").decode_string() == memid)
+ ignore_data_port = true;
+
+ for (auto conn : cell_it.second->connections)
+ {
+ if (ignore_data_port && conn.first == "\\DATA")
+ continue;
+ std::vector<RTLIL::SigBit> bits = sigmap(conn.second);
+ non_feedback_nets.insert(bits.begin(), bits.end());
+ }
+ }
+
+ std::set<RTLIL::SigBit> expand_non_feedback_nets = non_feedback_nets;
+ while (!expand_non_feedback_nets.empty())
+ {
+ std::set<RTLIL::SigBit> new_expand_non_feedback_nets;
+
+ for (auto &bit : expand_non_feedback_nets)
+ if (muxtree_upstream_map.count(bit))
+ for (auto &new_bit : muxtree_upstream_map.at(bit))
+ if (!non_feedback_nets.count(new_bit)) {
+ non_feedback_nets.insert(new_bit);
+ new_expand_non_feedback_nets.insert(new_bit);
+ }
+
+ expand_non_feedback_nets.swap(new_expand_non_feedback_nets);
+ }
+
+ for (auto cell : rd_ports)
+ {
+ if (cell->parameters.at("\\CLK_ENABLE").as_bool())
+ continue;
+
+ std::vector<RTLIL::SigBit> sig_data = sigmap(cell->connections.at("\\DATA"));
+
+ for (int i = 0; i < int(sig_data.size()); i++)
+ if (non_feedback_nets.count(sig_data[i]))
+ goto not_pure_feedback_port;
+
+ async_rd_bits.resize(std::max(async_rd_bits.size(), sig_data.size()));
+ for (int i = 0; i < int(sig_data.size()); i++)
+ async_rd_bits[i].insert(sig_data[i]);
+
+ not_pure_feedback_port:;
+ }
+
+ if (async_rd_bits.empty())
+ return;
+
+ log("Populating enable bits on write ports of memory %s with aync read feedback:\n", log_id(memid));
+
+ for (auto cell : wr_ports)
+ {
+ log(" Analyzing write port %s.\n", log_id(cell));
+
+ std::vector<RTLIL::SigBit> cell_data = cell->connections.at("\\DATA");
+ std::vector<RTLIL::SigBit> cell_en = cell->connections.at("\\EN");
+
+ int created_conditions = 0;
+ for (int i = 0; i < int(cell_data.size()); i++)
+ if (cell_en[i] != RTLIL::SigBit(RTLIL::State::S0))
+ {
+ std::map<RTLIL::SigBit, bool> state;
+ std::set<std::map<RTLIL::SigBit, bool>> conditions;
+
+ if (cell_en[i].wire != NULL) {
+ state[cell_en[i]] = false;
+ conditions.insert(state);
+ }
+
+ find_data_feedback(async_rd_bits.at(i), cell_data[i], state, conditions);
+ cell_en[i] = conditions_to_logic(conditions, created_conditions);
+ }
+
+ if (created_conditions) {
+ log(" Added enable logic for %d different cases.\n", created_conditions);
+ cell->connections.at("\\EN") = cell_en;
+ }
+ }
+ }
+
+
+ // ------------------------------------------------------
+ // Consolidate write ports that write to the same address
+ // ------------------------------------------------------
RTLIL::SigSpec mask_en_naive(RTLIL::SigSpec do_mask, RTLIL::SigSpec bits, RTLIL::SigSpec mask_bits)
{
@@ -143,7 +345,7 @@ struct MemoryShareWorker
for (int i = 0; i < int(wr_ports.size()); i++)
{
RTLIL::Cell *cell = wr_ports.at(i);
- RTLIL::SigSpec addr = sigmap(cell->connections.at("\\ADDR"));
+ RTLIL::SigSpec addr = sigmap_xmux(cell->connections.at("\\ADDR"));
if (cell->parameters.at("\\CLK_ENABLE").as_bool() != cache_clk_enable ||
(cache_clk_enable && (sigmap(cell->connections.at("\\CLK")) != cache_clk ||
@@ -212,17 +414,18 @@ struct MemoryShareWorker
}
// Then we need to merge the (masked) EN and the DATA signals.
- // Note that we intentionally do not use sigmap() on the DATA ports.
RTLIL::SigSpec merged_data = wr_ports[last_i]->connections.at("\\DATA");
if (found_overlapping_bits) {
log(" Creating logic for merging DATA and EN ports.\n");
- merge_en_data(merged_en, merged_data, sigmap(cell->connections.at("\\EN")), cell->connections.at("\\DATA"));
+ merge_en_data(merged_en, merged_data, sigmap(cell->connections.at("\\EN")), sigmap(cell->connections.at("\\DATA")));
} else {
+ RTLIL::SigSpec cell_en = sigmap(cell->connections.at("\\EN"));
+ RTLIL::SigSpec cell_data = sigmap(cell->connections.at("\\DATA"));
for (int k = 0; k < int(en_bits.size()); k++)
if (!active_bits_on_port[last_i][k]) {
- merged_en.replace(k, cell->connections.at("\\EN").extract(k, 1));
- merged_data.replace(k, cell->connections.at("\\DATA").extract(k, 1));
+ merged_en.replace(k, cell_en.extract(k, 1));
+ merged_data.replace(k, cell_data.extract(k, 1));
}
merged_en.optimize();
merged_data.optimize();
@@ -247,13 +450,28 @@ struct MemoryShareWorker
last_port_by_addr[addr] = i;
}
+
+ // Clean up `wr_ports': remove all NULL entries
+
+ std::vector<RTLIL::Cell*> wr_ports_with_nulls;
+ wr_ports_with_nulls.swap(wr_ports);
+
+ for (auto cell : wr_ports_with_nulls)
+ if (cell != NULL)
+ wr_ports.push_back(cell);
}
+
+ // -------------
+ // Setup and run
+ // -------------
+
MemoryShareWorker(RTLIL::Design *design, RTLIL::Module *module) :
design(design), module(module), sigmap(module)
{
std::map<std::string, std::pair<std::vector<RTLIL::Cell*>, std::vector<RTLIL::Cell*>>> memindex;
+ sigmap_xmux = sigmap;
for (auto &it : module->cells)
{
RTLIL::Cell *cell = it.second;
@@ -266,19 +484,27 @@ struct MemoryShareWorker
if (cell->type == "$mux")
{
- RTLIL::SigSpec sig_a = sigmap(cell->connections.at("\\A"));
- RTLIL::SigSpec sig_b = sigmap(cell->connections.at("\\B"));
+ RTLIL::SigSpec sig_a = sigmap_xmux(cell->connections.at("\\A"));
+ RTLIL::SigSpec sig_b = sigmap_xmux(cell->connections.at("\\B"));
if (sig_a.is_fully_undef())
- sigmap.add(cell->connections.at("\\Y"), sig_b);
+ sigmap_xmux.add(cell->connections.at("\\Y"), sig_b);
else if (sig_b.is_fully_undef())
- sigmap.add(cell->connections.at("\\Y"), sig_a);
+ sigmap_xmux.add(cell->connections.at("\\Y"), sig_a);
+ }
+
+ if (cell->type == "$mux" || cell->type == "$pmux")
+ {
+ std::vector<RTLIL::SigBit> sig_y = sigmap(cell->connections.at("\\Y"));
+ for (int i = 0; i < int(sig_y.size()); i++)
+ sig_to_mux[sig_y[i]] = std::pair<RTLIL::Cell*, int>(cell, i);
}
}
for (auto &it : memindex) {
std::sort(it.second.first.begin(), it.second.first.end(), memcells_cmp);
std::sort(it.second.second.begin(), it.second.second.end(), memcells_cmp);
+ translate_rd_feedback_to_en(it.first, it.second.first, it.second.second);
consolidate_wr_by_addr(it.first, it.second.second);
}
}