mirrors/yosys
3
0
Fork 0
mirror of https://github.com/YosysHQ/yosys synced 2025-10-31 03:32:29 +00:00
Code Activity

Replace "muxcover -freedecode" with "muxcover -dmux=cost"

Browse source 
Signed-off-by: Clifford Wolf <clifford@clifford.at>
This commit is contained in:
Clifford Wolf 2019-06-21 19:24:41 +02:00
parent 9286b6f013
commit ec979475e7
1 changed files with 14 additions and 15 deletions
Download patch file Download diff file Expand all files Collapse all files

29
passes/techmap/muxcover.cc
View file

@ -23,6 +23,7 @@
USING_YOSYS_NAMESPACE USING_YOSYS_NAMESPACE
PRIVATE_NAMESPACE_BEGIN PRIVATE_NAMESPACE_BEGIN
#define COST_DMUX 90
#define COST_MUX2 100 #define COST_MUX2 100
#define COST_MUX4 220 #define COST_MUX4 220
#define COST_MUX8 460 #define COST_MUX8 460
@ -57,9 +58,9 @@ struct MuxcoverWorker
bool use_mux8; bool use_mux8;
bool use_mux16; bool use_mux16;
bool nodecode; bool nodecode;
bool freedecode;
bool nopartial; bool nopartial;
int cost_dmux;
int cost_mux2; int cost_mux2;
int cost_mux4; int cost_mux4;
int cost_mux8; int cost_mux8;
@ -71,8 +72,8 @@ struct MuxcoverWorker
use_mux8 = false; use_mux8 = false;
use_mux16 = false; use_mux16 = false;
nodecode = false; nodecode = false;
freedecode = false;
nopartial = false; nopartial = false;
cost_dmux = COST_DMUX;
cost_mux2 = COST_MUX2; cost_mux2 = COST_MUX2;
cost_mux4 = COST_MUX4; cost_mux4 = COST_MUX4;
cost_mux8 = COST_MUX8; cost_mux8 = COST_MUX8;
@ -180,10 +181,7 @@ struct MuxcoverWorker
if (A == State::Sx || B == State::Sx) if (A == State::Sx || B == State::Sx)
return 0; return 0;
if (freedecode) return cost_dmux / GetSize(std::get<1>(entry));
return 0;
return std::max((cost_mux2 / GetSize(std::get<1>(entry))) - 1, 1);
} }
void implement_decode_mux(SigBit ctrl_bit) void implement_decode_mux(SigBit ctrl_bit)
@ -620,14 +618,15 @@ struct MuxcoverPass : public Pass {
log(" Default costs: $_MUX_ = %d, $_MUX4_ = %d,\n", COST_MUX2, COST_MUX4); log(" Default costs: $_MUX_ = %d, $_MUX4_ = %d,\n", COST_MUX2, COST_MUX4);
log(" $_MUX8_ = %d, $_MUX16_ = %d\n", COST_MUX8, COST_MUX16); log(" $_MUX8_ = %d, $_MUX16_ = %d\n", COST_MUX8, COST_MUX16);
log("\n"); log("\n");
log(" -dmux=cost\n");
log(" Use the specified cost for $_MUX_ cells used in decoders.\n");
log(" Default cost: %d\n", COST_DMUX);
log("\n");
log(" -nodecode\n"); log(" -nodecode\n");
log(" Do not insert decoder logic. This reduces the number of possible\n"); log(" Do not insert decoder logic. This reduces the number of possible\n");
log(" substitutions, but guarantees that the resulting circuit is not\n"); log(" substitutions, but guarantees that the resulting circuit is not\n");
log(" less efficient than the original circuit.\n"); log(" less efficient than the original circuit.\n");
log("\n"); log("\n");
log(" -freedecode\n");
log(" Do not count cost for generated decode logic\n");
log("\n");
log(" -nopartial\n"); log(" -nopartial\n");
log(" Do not consider mappings that use $_MUX<N>_ to select from less\n"); log(" Do not consider mappings that use $_MUX<N>_ to select from less\n");
log(" than <N> different signals.\n"); log(" than <N> different signals.\n");
@ -641,8 +640,8 @@ struct MuxcoverPass : public Pass {
bool use_mux8 = false; bool use_mux8 = false;
bool use_mux16 = false; bool use_mux16 = false;
bool nodecode = false; bool nodecode = false;
bool freedecode = false;
bool nopartial = false; bool nopartial = false;
int cost_dmux = COST_DMUX;
int cost_mux4 = COST_MUX4; int cost_mux4 = COST_MUX4;
int cost_mux8 = COST_MUX8; int cost_mux8 = COST_MUX8;
int cost_mux16 = COST_MUX16; int cost_mux16 = COST_MUX16;
@ -675,12 +674,12 @@ struct MuxcoverPass : public Pass {
} }
continue; continue;
} }
if (arg == "-nodecode") { if (arg.size() >= 6 && arg.substr(0,6) == "-dmux=") {
nodecode = true; cost_dmux = atoi(arg.substr(6).c_str());
continue; continue;
} }
if (arg == "-freedecode") { if (arg == "-nodecode") {
freedecode = true; nodecode = true;
continue; continue;
} }
if (arg == "-nopartial") { if (arg == "-nopartial") {
@ -703,11 +702,11 @@ struct MuxcoverPass : public Pass {
worker.use_mux4 = use_mux4; worker.use_mux4 = use_mux4;
worker.use_mux8 = use_mux8; worker.use_mux8 = use_mux8;
worker.use_mux16 = use_mux16; worker.use_mux16 = use_mux16;
worker.cost_dmux = cost_dmux;
worker.cost_mux4 = cost_mux4; worker.cost_mux4 = cost_mux4;
worker.cost_mux8 = cost_mux8; worker.cost_mux8 = cost_mux8;
worker.cost_mux16 = cost_mux16; worker.cost_mux16 = cost_mux16;
worker.nodecode = nodecode; worker.nodecode = nodecode;
worker.freedecode = freedecode;
worker.nopartial = nopartial; worker.nopartial = nopartial;
worker.run(); worker.run();
} }