diff --git a/passes/techmap/mcm.cc b/passes/techmap/mcm.cc
index e7a64f6f6..654f8232e 100644
--- a/passes/techmap/mcm.cc
+++ b/passes/techmap/mcm.cc
@@ -61,6 +61,7 @@ struct AdderGraph {
 enum class AdderGraphStatus {
 	success,
 	no_graph,
+	node_limit,
 	budget_exhausted,
 };
 
@@ -111,10 +112,14 @@ struct SearchParams {
 	SearchResult &result;
 };
 
+struct SearchState;
+
 class Scorer {
 public:
 	virtual bool better(const AdderGraphCandidate &candidate, const AdderGraphCandidate &selected,
 			bool direct_target) const = 0;
+	virtual bool score_intermediate(SearchState &state, const AdderGraphCandidate &candidate, 
+		const pool<int> &remaining, int &score) const = 0;
 	virtual ~Scorer() = default;
 };
 
@@ -131,6 +136,10 @@ public:
 			return candidate.depth < selected.depth;
 		return candidate.value < selected.value;
 	}
+
+	bool score_intermediate(SearchState &state, const AdderGraphCandidate &candidate,
+        const pool<int> &remaining, int &score) const override;
+
 };
 
 struct SearchState {
@@ -240,36 +249,12 @@ struct SearchState {
 		return selected.value >= 0;
 	}
 
-	// Score an intermediate by how many targets it makes reachable in one step.
-	bool score_intermediate(const AdderGraphCandidate &candidate, const pool<int> &remaining, int &score)
-	{
-		pool<int> unlocked;
-		for (auto &node : graph.depth) {
-			if (1 + std::max(candidate.depth, node.second) > config.max_depth)
-				continue;
-			for (auto &op : enumerate_pair(candidate.value, node.first))
-				if (remaining.count(op.res))
-					unlocked.insert(op.res);
-			if (budget_exhausted)
-				return false;
-		}
-		if (1 + candidate.depth <= config.max_depth) {
-			for (auto &op : enumerate_pair(candidate.value, candidate.value))
-				if (remaining.count(op.res))
-					unlocked.insert(op.res);
-			if (budget_exhausted)
-				return false;
-		}
-		score = GetSize(unlocked);
-		return true;
-	}
-
 	bool select_intermediate(const CandidateMap &candidates, const pool<int> &remaining,
 			AdderGraphCandidate &selected, const Scorer &scorer)
 	{
 		for (auto &entry : candidates) {
 			AdderGraphCandidate candidate = entry.second;
-			if (!score_intermediate(candidate, remaining, candidate.score))
+			if (!scorer.score_intermediate(*this, candidate, remaining, candidate.score))
 				return false;
 			if (scorer.better(candidate, selected, false))
 				selected = candidate;
@@ -303,6 +288,31 @@ struct SearchState {
 	}
 };
 
+// Score an intermediate by how many targets it makes reachable in one step.
+bool HcubScorer::score_intermediate(SearchState &state, const AdderGraphCandidate &candidate,
+	 const pool<int> &remaining, int &score) const
+{
+	pool<int> unlocked;
+	for (auto &node : state.graph.depth) {
+		if (1 + std::max(candidate.depth, node.second) > state.config.max_depth)
+			continue;
+		for (auto &op : state.enumerate_pair(candidate.value, node.first))
+			if (remaining.count(op.res))
+				unlocked.insert(op.res);
+		if (state.budget_exhausted)
+			return false;
+	}
+	if (1 + candidate.depth <= state.config.max_depth) {
+		for (auto &op : state.enumerate_pair(candidate.value, candidate.value))
+			if (remaining.count(op.res))
+				unlocked.insert(op.res);
+		if (state.budget_exhausted)
+			return false;
+	}
+	score = GetSize(unlocked);
+	return true;
+}
+
 class Search {
 public:
 	virtual void search(const SearchParams &params, const Scorer &scorer) = 0;
@@ -333,7 +343,7 @@ public:
 			if (remaining.empty())
 				break;
 			if (committed_nodes >= state.config.max_nodes) {
-				params.result.status = AdderGraphStatus::no_graph;
+				params.result.status = AdderGraphStatus::node_limit;
 				return;
 			}
 
@@ -624,6 +634,9 @@ struct McmWorker {
 			if (status == AdderGraphStatus::budget_exhausted)
 				log("  mcm: search budget of %lld exhausted for %d constant(s), skipping.\n",
 						config.search.work_budget, GetSize(group.items));
+			else if (status == AdderGraphStatus::node_limit)
+				log("  mcm: maximum node count %d reached for %d constant(s), skipping.\n",
+						config.search.max_nodes, GetSize(group.items));
 			else
 				log("  mcm: no adder graph within depth %d for %d constant(s), skipping.\n",
 						config.search.max_depth, GetSize(group.items));
@@ -670,6 +683,9 @@ struct McmPass : public Pass {
 		log("    -max_shift <n>\n");
 		log("        largest shift considered in an A-operation (default: 12).\n");
 		log("\n");
+		log("    -max_nodes <n>\n");
+		log("        maximum nember of nodes (default: 64).\n");
+		log("\n");
 		log("    -min_const <n>\n");
 		log("        skip constants whose magnitude is below <n> (default: 3).\n");
 		log("\n");
@@ -705,6 +721,12 @@ struct McmPass : public Pass {
 					log_cmd_error("mcm: -max_shift must be >= 1\n");
 				continue;
 			}
+			if (args[argidx] == "-max_nodes" && argidx + 1 < args.size()) {
+				config.search.max_nodes = atoi(args[++argidx].c_str());
+				if (config.search.max_nodes < 1)
+					log_cmd_error("mcm: -max_nodes must be >= 1\n");
+				continue;
+			}
 			if (args[argidx] == "-min_const" && argidx + 1 < args.size()) {
 				config.min_const = atoi(args[++argidx].c_str());
 				continue;
diff --git a/tests/techmap/mcm.ys b/tests/techmap/mcm.ys
index d8ff17ed9..d0bb41619 100644
--- a/tests/techmap/mcm.ys
+++ b/tests/techmap/mcm.ys
@@ -45,26 +45,40 @@ EOF
 equiv_opt -assert mcm -force
 design -load postopt
 select -assert-count 0 t:$mul
-select -assert-count 3 t:$add t:$sub
+select -assert-max 3 t:$add t:$sub
 
 design -reset
 
-log -header "MCM profitability threshold can reject graphs"
+log -header "MCM accepts a graph at the gain threshold"
 read_verilog <<EOF
 module top(
   input  wire [7:0] x,
-  input  wire [7:0] singleton_x,
-  output wire [15:0] singleton,
   output wire [15:0] a,
   output wire [15:0] b
 );
-  assign singleton = singleton_x * 16'd397;
   assign a = x * 16'd3;
-  assign b = x * 16'd5;
+  assign b = x * 16'd21;
 endmodule
 EOF
-mcm -min_gain 100
-select -assert-count 3 t:$mul
+equiv_opt -assert mcm -min_gain 33
+design -load postopt
+select -assert-count 0 t:$mul
+
+design -reset
+
+log -header "MCM rejects a graph above its gain"
+read_verilog <<EOF
+module top(
+  input  wire [7:0] x,
+  output wire [15:0] a,
+  output wire [15:0] b
+);
+  assign a = x * 16'd3;
+  assign b = x * 16'd21;
+endmodule
+EOF
+mcm -min_gain 34
+select -assert-count 2 t:$mul
 
 design -reset