dfflibmap: reproduce dffe test oddity

YosysHQ · Dec 9, 2024 · 1f125a5 · 1f125a5
1 parent 5233636
commit 1f125a5
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Showing 3 changed files with 44 additions and 6 deletions.
diff --git a/tests/techmap/dfflibmap-sim.v b/tests/techmap/dfflibmap-sim.v
@@ -20,3 +20,12 @@ always @(posedge CLK, posedge CLEAR, posedge PRESET)
 assign QN = ~Q;
 
 endmodule
+
+module dffe(input CLK, EN, D, output reg Q, output QN);
+
+always @(negedge CLK)
+	if (EN) Q <= D;
+
+assign QN = ~Q;
+
+endmodule
diff --git a/tests/techmap/dfflibmap.lib b/tests/techmap/dfflibmap.lib
@@ -52,4 +52,28 @@ library(test) {
       function : "IQN";
     } 
   }
+  cell (dffe) {
+    area : 6;
+    ff("IQ", "IQN") {
+      next_state : "(D&DE) | (IQ&!DE)";
+      clocked_on : "!CLK";
+    } 
+    pin(D) {
+      direction : input;
+    }
+    pin(DE) {
+      direction : input;
+    }
+    pin(CLK) {
+      direction : input;
+    }
+    pin(Q) {
+      direction: output;
+      function : "IQ";
+    }
+    pin(QN) {
+      direction: output;
+      function : "IQN";
+    } 
+  }
 }
diff --git a/tests/techmap/dfflibmap.ys b/tests/techmap/dfflibmap.ys
@@ -1,14 +1,15 @@
+# $_DFF_PP0_ ff1 (.C(C), .D(D), .R(R), .Q(Q[1]));
+# $_DFF_PP1_ ff2 (.C(C), .D(D), .R(R), .Q(Q[2]));
+# $_DFFSR_PPP_ ff3 (.C(C), .D(D), .R(R), .S(S), .Q(Q[3]));
+# $_DFFSR_NNN_ ff4 (.C(C), .D(D), .R(R), .S(S), .Q(Q[4]));
 read_verilog -icells <<EOT
 
-module top(input C, D, S, R, output [9:0] Q);
+module top(input C, D, E, S, R, output [11:0] Q);
 
 $_DFF_P_ ff0 (.C(C), .D(D), .Q(Q[0]));
-$_DFF_PP0_ ff1 (.C(C), .D(D), .R(R), .Q(Q[1]));
-$_DFF_PP1_ ff2 (.C(C), .D(D), .R(R), .Q(Q[2]));
-$_DFFSR_PPP_ ff3 (.C(C), .D(D), .R(R), .S(S), .Q(Q[3]));
-$_DFFSR_NNN_ ff4 (.C(C), .D(D), .R(R), .S(S), .Q(Q[4]));
+$_DFFE_PP_ ff5 (.C(C), .D(D), .E(E), .Q(Q[5]));
 
-assign Q[9:5] = ~Q[4:0];
+assign Q[11:6] = ~Q[5:0];
 
 endmodule
 
@@ -19,6 +20,10 @@ simplemap
 design -save orig
 read_liberty -lib dfflibmap.lib
 
+dfflibmap -liberty dfflibmap.lib
+stat
+debug techmap -assert -wb -D EQUIV -autoproc -map dfflibmap-sim.v
+
 equiv_opt -map dfflibmap-sim.v -assert -multiclock dfflibmap -liberty dfflibmap.lib
 equiv_opt -map dfflibmap-sim.v -assert -multiclock dfflibmap -prepare -liberty dfflibmap.lib