Fix expression coverage + VarXRefs (#5797)

src/V3Coverage.cpp

@@ -726,7 +726,7 @@ class CoverageVisitor final : public VNVisitor {
                 // not be flagged as redundant or impossible, however the results will
                 // still be valid, albeit messier
                 for (CoverTerm& term : l) {
-                    if (AstNodeVarRef* const refp = VN_CAST(term.m_exprp, NodeVarRef)) {
+                    if (AstVarRef* const refp = VN_CAST(term.m_exprp, VarRef)) {
                         varps[term.m_objective].insert(refp->varp());
                     } else {
                         strs[term.m_objective].insert(term.m_emitV);

test_regress/t/t_cover_expr.out

@@ -43,6 +43,13 @@
 -000005  point: comment=(b==0) => 0 hier=top.t
             endfunction
         
+            localparam int num_intfs = 4;
+            intf the_intfs [num_intfs-1:0] ();
+            genvar intf_i;
+            for (intf_i = 0; intf_i < num_intfs; intf_i++) begin
+                always_comb the_intfs[intf_i].t = cyc[intf_i];
+            end
+        
             always @ (posedge clk) begin
                 cyc <= cyc + 1;
 %000004         if ((~cyc[0] && cyc[1]) || (~cyc[2] && cyc[3])) $write("");
@@ -59,6 +66,13 @@
 -000002  point: comment=(cyc2[33]==0 && cyc2[34]==1) => 0 hier=top.t
 -000003  point: comment=(cyc2[33]==0 && cyc2[35]==0) => 0 hier=top.t
 -000002  point: comment=(cyc2[34]==0 && cyc2[35]==1) => 1 hier=top.t
+%000004         if ((~the_intfs[0].t && the_intfs[1].t) || (~the_intfs[2].t && the_intfs[3].t)) $write("");
+-000002  point: comment=(the_intfs[0].t==0 && the_intfs[1].t==1) => 1 hier=top.t
+-000002  point: comment=(the_intfs[0].t==1 && the_intfs[2].t==1) => 0 hier=top.t
+-000004  point: comment=(the_intfs[0].t==1 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[1].t==0 && the_intfs[2].t==1) => 0 hier=top.t
+-000003  point: comment=(the_intfs[1].t==0 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[2].t==0 && the_intfs[3].t==1) => 1 hier=top.t
 %000004         if ((~t1 && t2) || (~t3 && t4)) $write("");
 -000002  point: comment=(t1==0 && t2==1) => 1 hier=top.t
 -000002  point: comment=(t1==1 && t3==1) => 0 hier=top.t
@@ -325,3 +339,7 @@
         
         endmodule
         
+        interface intf();
+            logic t;
+        endinterface
+        

test_regress/t/t_cover_expr.v

@@ -37,10 +37,18 @@ module t (/*AUTOARG*/
         return a & b;
     endfunction
 
+    localparam int num_intfs = 4;
+    intf the_intfs [num_intfs-1:0] ();
+    genvar intf_i;
+    for (intf_i = 0; intf_i < num_intfs; intf_i++) begin
+        always_comb the_intfs[intf_i].t = cyc[intf_i];
+    end
+
     always @ (posedge clk) begin
         cyc <= cyc + 1;
         if ((~cyc[0] && cyc[1]) || (~cyc[2] && cyc[3])) $write("");
         if ((~cyc2[32] && cyc2[33]) || (~cyc2[34] && cyc2[35])) $write("");
+        if ((~the_intfs[0].t && the_intfs[1].t) || (~the_intfs[2].t && the_intfs[3].t)) $write("");
         if ((~t1 && t2) || (~t3 && t4)) $write("");
         if (t3 && (t1 == t2)) $write("");
         if (123 == (124 - 32'(t1 || t2))) $write("");
@@ -163,3 +171,7 @@ module sub (
     end
 
 endmodule
+
+interface intf();
+    logic t;
+endinterface

test_regress/t/t_cover_expr_max.out

@@ -43,6 +43,13 @@
 -000005  point: comment=(b==0) => 0 hier=top.t
             endfunction
         
+            localparam int num_intfs = 4;
+            intf the_intfs [num_intfs-1:0] ();
+            genvar intf_i;
+            for (intf_i = 0; intf_i < num_intfs; intf_i++) begin
+                always_comb the_intfs[intf_i].t = cyc[intf_i];
+            end
+        
             always @ (posedge clk) begin
                 cyc <= cyc + 1;
 %000004         if ((~cyc[0] && cyc[1]) || (~cyc[2] && cyc[3])) $write("");
@@ -59,6 +66,13 @@
 -000002  point: comment=(cyc2[33]==0 && cyc2[34]==1) => 0 hier=top.t
 -000003  point: comment=(cyc2[33]==0 && cyc2[35]==0) => 0 hier=top.t
 -000002  point: comment=(cyc2[34]==0 && cyc2[35]==1) => 1 hier=top.t
+%000004         if ((~the_intfs[0].t && the_intfs[1].t) || (~the_intfs[2].t && the_intfs[3].t)) $write("");
+-000002  point: comment=(the_intfs[0].t==0 && the_intfs[1].t==1) => 1 hier=top.t
+-000002  point: comment=(the_intfs[0].t==1 && the_intfs[2].t==1) => 0 hier=top.t
+-000004  point: comment=(the_intfs[0].t==1 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[1].t==0 && the_intfs[2].t==1) => 0 hier=top.t
+-000003  point: comment=(the_intfs[1].t==0 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[2].t==0 && the_intfs[3].t==1) => 1 hier=top.t
 %000004         if ((~t1 && t2) || (~t3 && t4)) $write("");
 -000002  point: comment=(t1==0 && t2==1) => 1 hier=top.t
 -000002  point: comment=(t1==1 && t3==1) => 0 hier=top.t
@@ -453,3 +467,7 @@
         
         endmodule
         
+        interface intf();
+            logic t;
+        endinterface
+        

test_regress/t/t_cover_expr_trace.out

@@ -43,6 +43,13 @@
 -000005  point: comment=(b==0) => 0 hier=top.t
             endfunction
         
+            localparam int num_intfs = 4;
+            intf the_intfs [num_intfs-1:0] ();
+            genvar intf_i;
+            for (intf_i = 0; intf_i < num_intfs; intf_i++) begin
+                always_comb the_intfs[intf_i].t = cyc[intf_i];
+            end
+        
             always @ (posedge clk) begin
                 cyc <= cyc + 1;
 %000004         if ((~cyc[0] && cyc[1]) || (~cyc[2] && cyc[3])) $write("");
@@ -59,6 +66,13 @@
 -000002  point: comment=(cyc2[33]==0 && cyc2[34]==1) => 0 hier=top.t
 -000003  point: comment=(cyc2[33]==0 && cyc2[35]==0) => 0 hier=top.t
 -000002  point: comment=(cyc2[34]==0 && cyc2[35]==1) => 1 hier=top.t
+%000004         if ((~the_intfs[0].t && the_intfs[1].t) || (~the_intfs[2].t && the_intfs[3].t)) $write("");
+-000002  point: comment=(the_intfs[0].t==0 && the_intfs[1].t==1) => 1 hier=top.t
+-000002  point: comment=(the_intfs[0].t==1 && the_intfs[2].t==1) => 0 hier=top.t
+-000004  point: comment=(the_intfs[0].t==1 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[1].t==0 && the_intfs[2].t==1) => 0 hier=top.t
+-000003  point: comment=(the_intfs[1].t==0 && the_intfs[3].t==0) => 0 hier=top.t
+-000002  point: comment=(the_intfs[2].t==0 && the_intfs[3].t==1) => 1 hier=top.t
 %000004         if ((~t1 && t2) || (~t3 && t4)) $write("");
 -000002  point: comment=(t1==0 && t2==1) => 1 hier=top.t
 -000002  point: comment=(t1==1 && t3==1) => 0 hier=top.t
@@ -325,3 +339,7 @@
         
         endmodule
         
+        interface intf();
+            logic t;
+        endinterface
+