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Diffstat (limited to 'passes/memory/memory_dff.cc')
-rw-r--r--passes/memory/memory_dff.cc24
1 files changed, 21 insertions, 3 deletions
diff --git a/passes/memory/memory_dff.cc b/passes/memory/memory_dff.cc
index 40691d16..32df1917 100644
--- a/passes/memory/memory_dff.cc
+++ b/passes/memory/memory_dff.cc
@@ -33,8 +33,20 @@ struct MemoryDffWorker
dict<SigBit, int> sigbit_users_count;
dict<SigSpec, Cell*> mux_cells_a, mux_cells_b;
pool<Cell*> forward_merged_dffs, candidate_dffs;
+ pool<SigBit> init_bits;
- MemoryDffWorker(Module *module) : module(module), sigmap(module) { }
+ MemoryDffWorker(Module *module) : module(module), sigmap(module)
+ {
+ for (auto wire : module->wires()) {
+ if (wire->attributes.count("\\init") == 0)
+ continue;
+ SigSpec sig = sigmap(wire);
+ Const initval = wire->attributes.count("\\init");
+ for (int i = 0; i < GetSize(sig) && i < GetSize(initval); i++)
+ if (initval[i] == State::S0 || initval[i] == State::S1)
+ init_bits.insert(sig[i]);
+ }
+ }
bool find_sig_before_dff(RTLIL::SigSpec &sig, RTLIL::SigSpec &clk, bool &clk_polarity, bool after = false)
{
@@ -45,6 +57,9 @@ struct MemoryDffWorker
if (bit.wire == NULL)
continue;
+ if (!after && init_bits.count(sigmap(bit)))
+ return false;
+
for (auto cell : dff_cells)
{
if (after && forward_merged_dffs.count(cell))
@@ -72,6 +87,9 @@ struct MemoryDffWorker
if (d.size() != 1)
continue;
+ if (after && init_bits.count(d))
+ return false;
+
bit = d;
clk = this_clk;
clk_polarity = this_clk_polarity;
@@ -265,7 +283,7 @@ struct MemoryDffWorker
struct MemoryDffPass : public Pass {
MemoryDffPass() : Pass("memory_dff", "merge input/output DFFs into memories") { }
- virtual void help()
+ void help() YS_OVERRIDE
{
// |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
log("\n");
@@ -279,7 +297,7 @@ struct MemoryDffPass : public Pass {
log(" do not merge registers on read ports\n");
log("\n");
}
- virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+ void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
{
bool flag_wr_only = false;