summaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorClifford Wolf <clifford@clifford.at>2014-01-03 17:30:50 +0100
committerClifford Wolf <clifford@clifford.at>2014-01-03 17:30:50 +0100
commit7354a1718e2e3f2eec4843a56410743af0ff7a83 (patch)
tree51fb2734c5119a00f5de5acee456432389a6f2d6 /kernel
parent8a8d444648bd1744c2598854367fd14d143aeb78 (diff)
Fixed SAT and ConstEval undef handling for $pmux and $safe_pmux
Diffstat (limited to 'kernel')
-rw-r--r--kernel/consteval.h10
-rw-r--r--kernel/satgen.h43
2 files changed, 43 insertions, 10 deletions
diff --git a/kernel/consteval.h b/kernel/consteval.h
index a424007e..10116ccf 100644
--- a/kernel/consteval.h
+++ b/kernel/consteval.h
@@ -110,6 +110,7 @@ struct ConstEval
if (cell->type == "$mux" || cell->type == "$pmux" || cell->type == "$safe_pmux" || cell->type == "$_MUX_")
{
std::vector<RTLIL::SigSpec> y_candidates;
+ int count_maybe_set_s_bits = 0;
int count_set_s_bits = 0;
for (int i = 0; i < sig_s.width; i++)
@@ -120,16 +121,17 @@ struct ConstEval
if (s_bit == RTLIL::State::Sx || s_bit == RTLIL::State::S1)
y_candidates.push_back(b_slice);
+ if (s_bit == RTLIL::State::S1 || s_bit == RTLIL::State::Sx)
+ count_maybe_set_s_bits++;
+
if (s_bit == RTLIL::State::S1)
count_set_s_bits++;
}
- if (cell->type == "$safe_pmux" && count_set_s_bits > 1) {
+ if (cell->type == "$safe_pmux" && count_set_s_bits > 1)
y_candidates.clear();
- count_set_s_bits = 0;
- }
- if (count_set_s_bits == 0)
+ if ((cell->type == "$safe_pmux" && count_maybe_set_s_bits > 1) || count_set_s_bits == 0)
y_candidates.push_back(sig_a);
std::vector<RTLIL::Const> y_values;
diff --git a/kernel/satgen.h b/kernel/satgen.h
index 208ae165..a668c73a 100644
--- a/kernel/satgen.h
+++ b/kernel/satgen.h
@@ -318,14 +318,45 @@ struct SatGen
std::vector<int> undef_s = importUndefSigSpec(cell->connections.at("\\S"), timestep);
std::vector<int> undef_y = importUndefSigSpec(cell->connections.at("\\Y"), timestep);
- tmp = a;
- for (size_t i = 0; i < s.size(); i++) {
+ int maybe_one_hot = ez->FALSE;
+ int maybe_many_hot = ez->FALSE;
+
+ int sure_one_hot = ez->FALSE;
+ int sure_many_hot = ez->FALSE;
+
+ std::vector<int> bits_set = std::vector<int>(undef_y.size(), ez->FALSE);
+ std::vector<int> bits_clr = std::vector<int>(undef_y.size(), ez->FALSE);
+
+ for (size_t i = 0; i < s.size(); i++)
+ {
+ std::vector<int> part_of_b(b.begin()+i*a.size(), b.begin()+(i+1)*a.size());
std::vector<int> part_of_undef_b(undef_b.begin()+i*a.size(), undef_b.begin()+(i+1)*a.size());
- tmp = ez->vec_ite(s.at(i), part_of_undef_b, tmp);
+
+ int maybe_s = ez->OR(s.at(i), undef_s.at(i));
+ int sure_s = ez->AND(s.at(i), ez->NOT(undef_s.at(i)));
+
+ maybe_one_hot = ez->OR(maybe_one_hot, maybe_s);
+ maybe_many_hot = ez->OR(maybe_many_hot, ez->AND(maybe_one_hot, maybe_s));
+
+ sure_one_hot = ez->OR(sure_one_hot, sure_s);
+ sure_many_hot = ez->OR(sure_many_hot, ez->AND(sure_one_hot, sure_s));
+
+ bits_set = ez->vec_ite(maybe_s, ez->vec_or(bits_set, ez->vec_or(bits_set, ez->vec_or(part_of_b, part_of_undef_b))), bits_set);
+ bits_clr = ez->vec_ite(maybe_s, ez->vec_or(bits_clr, ez->vec_or(bits_clr, ez->vec_or(ez->vec_not(part_of_b), part_of_undef_b))), bits_clr);
+ }
+
+ int maybe_a = ez->NOT(maybe_one_hot);
+
+ if (cell->type == "$safe_pmux") {
+ maybe_a = ez->OR(maybe_a, maybe_many_hot);
+ bits_set = ez->vec_ite(sure_many_hot, ez->vec_or(a, undef_a), bits_set);
+ bits_clr = ez->vec_ite(sure_many_hot, ez->vec_or(ez->vec_not(a), undef_a), bits_clr);
}
- tmp = ez->vec_ite(ez->onehot(s, true), tmp, cell->type == "$safe_pmux" ? a : std::vector<int>(tmp.size(), ez->TRUE));
- tmp = ez->vec_ite(ez->expression(ezSAT::OpOr, undef_s), std::vector<int>(tmp.size(), ez->TRUE), tmp);
- ez->assume(ez->vec_eq(tmp, undef_y));
+
+ bits_set = ez->vec_ite(maybe_a, ez->vec_or(bits_set, ez->vec_or(bits_set, ez->vec_or(a, undef_a))), bits_set);
+ bits_clr = ez->vec_ite(maybe_a, ez->vec_or(bits_clr, ez->vec_or(bits_clr, ez->vec_or(ez->vec_not(a), undef_a))), bits_clr);
+
+ ez->assume(ez->vec_eq(ez->vec_not(ez->vec_xor(bits_set, bits_clr)), undef_y));
undefGating(y, yy, undef_y);
}
return true;