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Diffstat (limited to 'passes/opt/wreduce.cc')
-rw-r--r--passes/opt/wreduce.cc50
1 files changed, 47 insertions, 3 deletions
diff --git a/passes/opt/wreduce.cc b/passes/opt/wreduce.cc
index 52245ce3..1fbc4108 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];
@@ -180,6 +181,8 @@ struct WreduceWorker
}
auto info = mi.query(sig_q[i]);
+ if (info == nullptr)
+ return;
if (!info->is_output && GetSize(info->ports) == 1 && !keep_bits.count(mi.sigmap(sig_q[i]))) {
remove_init_bits.insert(sig_q[i]);
sig_d.remove(i);
@@ -462,12 +465,10 @@ struct WreduceWorker
SigSpec initsig = init_attr_sigmap(w);
int width = std::min(GetSize(initval), GetSize(initsig));
for (int i = 0; i < width; i++) {
- log_dump(initsig[i], remove_init_bits.count(initsig[i]));
if (!remove_init_bits.count(initsig[i]))
new_initval[i] = initval[i];
}
w->attributes.at("\\init") = new_initval;
- log_dump(w->name, initval, new_initval);
}
}
}
@@ -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);