diff options
Diffstat (limited to 'passes/opt/wreduce.cc')
| -rw-r--r-- | passes/opt/wreduce.cc | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/passes/opt/wreduce.cc b/passes/opt/wreduce.cc index 41de8aad1..1fbc41082 100644 --- a/passes/opt/wreduce.cc +++ b/passes/opt/wreduce.cc @@ -29,6 +29,7 @@ PRIVATE_NAMESPACE_BEGIN struct WreduceConfig { pool<IdString> supported_cell_types; + bool keepdc = false; WreduceConfig() { @@ -82,7 +83,7 @@ struct WreduceWorker SigBit ref = sig_a[i]; for (int k = 0; k < GetSize(sig_s); k++) { - if (ref != Sx && sig_b[k*GetSize(sig_a) + i] != Sx && ref != sig_b[k*GetSize(sig_a) + i]) + if ((config->keepdc || (ref != Sx && sig_b[k*GetSize(sig_a) + i] != Sx)) && ref != sig_b[k*GetSize(sig_a) + i]) goto no_match_ab; if (sig_b[k*GetSize(sig_a) + i] != Sx) ref = sig_b[k*GetSize(sig_a) + i]; @@ -495,6 +496,9 @@ struct WreducePass : public Pass { log(" Do not change the width of memory address ports. Use this options in\n"); log(" flows that use the 'memory_memx' pass.\n"); log("\n"); + log(" -keepdc\n"); + log(" Do not optimize explicit don't-care values.\n"); + log("\n"); } void execute(std::vector<std::string> args, Design *design) YS_OVERRIDE { @@ -509,6 +513,10 @@ struct WreducePass : public Pass { opt_memx = true; continue; } + if (args[argidx] == "-keepdc") { + config.keepdc = true; + continue; + } break; } extra_args(args, argidx, design); @@ -531,6 +539,42 @@ struct WreducePass : public Pass { module->connect(sig, Const(0, GetSize(sig))); } } + + if (c->type.in("$div", "$mod", "$pow")) + { + SigSpec A = c->getPort("\\A"); + int original_a_width = GetSize(A); + if (c->getParam("\\A_SIGNED").as_bool()) { + while (GetSize(A) > 1 && A[GetSize(A)-1] == State::S0 && A[GetSize(A)-2] == State::S0) + A.remove(GetSize(A)-1, 1); + } else { + while (GetSize(A) > 0 && A[GetSize(A)-1] == State::S0) + A.remove(GetSize(A)-1, 1); + } + if (original_a_width != GetSize(A)) { + log("Removed top %d bits (of %d) from port A of cell %s.%s (%s).\n", + original_a_width-GetSize(A), original_a_width, log_id(module), log_id(c), log_id(c->type)); + c->setPort("\\A", A); + c->setParam("\\A_WIDTH", GetSize(A)); + } + + SigSpec B = c->getPort("\\B"); + int original_b_width = GetSize(B); + if (c->getParam("\\B_SIGNED").as_bool()) { + while (GetSize(B) > 1 && B[GetSize(B)-1] == State::S0 && B[GetSize(B)-2] == State::S0) + B.remove(GetSize(B)-1, 1); + } else { + while (GetSize(B) > 0 && B[GetSize(B)-1] == State::S0) + B.remove(GetSize(B)-1, 1); + } + if (original_b_width != GetSize(B)) { + log("Removed top %d bits (of %d) from port B of cell %s.%s (%s).\n", + original_b_width-GetSize(B), original_b_width, log_id(module), log_id(c), log_id(c->type)); + c->setPort("\\B", B); + c->setParam("\\B_WIDTH", GetSize(B)); + } + } + if (!opt_memx && c->type.in("$memrd", "$memwr", "$meminit")) { IdString memid = c->getParam("\\MEMID").decode_string(); RTLIL::Memory *mem = module->memories.at(memid); |