From 26f982ac0b69deb3cb9eda69e5cf687a69de4606 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Sat, 19 Jul 2014 15:32:14 +0200
Subject: [PATCH] Fixed bug in memory_share feedback-to-en code

---
 passes/memory/memory_share.cc   | 16 ++++++++++++----
 tests/memories/no_implicit_en.v | 24 ++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 4 deletions(-)
 create mode 100644 tests/memories/no_implicit_en.v

diff --git a/passes/memory/memory_share.cc b/passes/memory/memory_share.cc
index e2fa168c3..4af0ebdca 100644
--- a/passes/memory/memory_share.cc
+++ b/passes/memory/memory_share.cc
@@ -120,7 +120,7 @@ struct MemoryShareWorker
 
 	void translate_rd_feedback_to_en(std::string memid, std::vector<RTLIL::Cell*> &rd_ports, std::vector<RTLIL::Cell*> &wr_ports)
 	{
-		std::vector<std::set<RTLIL::SigBit>> async_rd_bits;
+		std::map<RTLIL::SigSpec, std::vector<std::set<RTLIL::SigBit>>> async_rd_bits;
 		std::map<RTLIL::SigBit, std::set<RTLIL::SigBit>> muxtree_upstream_map;
 		std::set<RTLIL::SigBit> non_feedback_nets;
 
@@ -187,15 +187,16 @@ struct MemoryShareWorker
 			if (cell->parameters.at("\\CLK_ENABLE").as_bool())
 				continue;
 
+			RTLIL::SigSpec sig_addr = sigmap(cell->connections.at("\\ADDR"));
 			std::vector<RTLIL::SigBit> sig_data = sigmap(cell->connections.at("\\DATA"));
 
 			for (int i = 0; i < int(sig_data.size()); i++)
 				if (non_feedback_nets.count(sig_data[i]))
 					goto not_pure_feedback_port;
 
-			async_rd_bits.resize(std::max(async_rd_bits.size(), sig_data.size()));
+			async_rd_bits[sig_addr].resize(std::max(async_rd_bits.size(), sig_data.size()));
 			for (int i = 0; i < int(sig_data.size()); i++)
-				async_rd_bits[i].insert(sig_data[i]);
+				async_rd_bits[sig_addr][i].insert(sig_data[i]);
 
 		not_pure_feedback_port:;
 		}
@@ -207,6 +208,10 @@ struct MemoryShareWorker
 
 		for (auto cell : wr_ports)
 		{
+			RTLIL::SigSpec sig_addr = sigmap_xmux(cell->connections.at("\\ADDR"));
+			if (!async_rd_bits.count(sig_addr))
+				continue;
+
 			log("  Analyzing write port %s.\n", log_id(cell));
 
 			std::vector<RTLIL::SigBit> cell_data = cell->connections.at("\\DATA");
@@ -224,7 +229,7 @@ struct MemoryShareWorker
 						conditions.insert(state);
 					}
 
-					find_data_feedback(async_rd_bits.at(i), cell_data[i], state, conditions);
+					find_data_feedback(async_rd_bits.at(sig_addr).at(i), cell_data[i], state, conditions);
 					cell_en[i] = conditions_to_logic(conditions, created_conditions);
 				}
 
@@ -333,6 +338,9 @@ struct MemoryShareWorker
 
 	void consolidate_wr_by_addr(std::string memid, std::vector<RTLIL::Cell*> &wr_ports)
 	{
+		if (wr_ports.size() <= 1)
+			return;
+
 		log("Consolidating write ports of memory %s by address:\n", log_id(memid));
 
 		std::map<RTLIL::SigSpec, int> last_port_by_addr;
diff --git a/tests/memories/no_implicit_en.v b/tests/memories/no_implicit_en.v
new file mode 100644
index 000000000..0e96e4ae1
--- /dev/null
+++ b/tests/memories/no_implicit_en.v
@@ -0,0 +1,24 @@
+// expect-wr-ports 1
+// expect-rd-ports 2
+
+module test(clk, rd_addr, rd_data, cp_addr, wr_addr, wr_en, wr_data);
+
+input clk;
+
+input [3:0] rd_addr;
+output reg [31:0] rd_data;
+
+input [3:0] cp_addr, wr_addr, wr_en;
+input [31:0] wr_data;
+
+reg [31:0] mem [0:15];
+
+always @(posedge clk) begin
+	mem[wr_addr][ 7: 0] <= wr_en[0] ? wr_data[ 7: 0] : mem[cp_addr][ 7: 0];
+	mem[wr_addr][15: 8] <= wr_en[1] ? wr_data[15: 8] : mem[cp_addr][15: 8];
+	mem[wr_addr][23:16] <= wr_en[2] ? wr_data[23:16] : mem[cp_addr][23:16];
+	mem[wr_addr][31:24] <= wr_en[3] ? wr_data[31:24] : mem[cp_addr][31:24];
+	rd_data <= mem[rd_addr];
+end
+
+endmodule
-- 
2.30.2