Fix panic with explicit clock and implicit reset

crates/emitter/src/emitter.rs

@@ -580,6 +580,25 @@ impl Emitter {
         }
     }
 
+    fn always_ff_explicit_event_list(
+        &mut self,
+        arg: &AlwaysFfEventList,
+        decl: &AlwaysFfDeclaration,
+    ) {
+        self.l_paren(&arg.l_paren);
+        self.always_ff_clock(&arg.always_ff_clock);
+        if let Some(ref x) = arg.always_ff_event_list_opt {
+            if self.always_ff_reset_exist_in_sensitivity_list(&x.always_ff_reset) {
+                self.comma(&x.comma);
+                self.space(1);
+            }
+            self.always_ff_reset(&x.always_ff_reset);
+        } else if self.always_ff_if_reset_exists(decl) {
+            self.always_ff_implicit_reset_event();
+        }
+        self.r_paren(&arg.r_paren);
+    }
+
     fn always_ff_implicit_event_list(&mut self, arg: &AlwaysFfDeclaration) {
         self.str("(");
         self.always_ff_implicit_clock_event();
@@ -2303,7 +2322,7 @@ impl VerylWalker for Emitter {
         self.str("@");
         self.space(1);
         if let Some(ref x) = arg.always_ff_declaration_opt {
-            self.always_ff_event_list(&x.always_ff_event_list);
+            self.always_ff_explicit_event_list(&x.always_ff_event_list, arg);
         } else {
             self.always_ff_implicit_event_list(arg);
         }
@@ -2312,20 +2331,6 @@ impl VerylWalker for Emitter {
         self.in_always_ff = false;
     }
 
-    /// Semantic action for non-terminal 'AlwaysFfEventList'
-    fn always_ff_event_list(&mut self, arg: &AlwaysFfEventList) {
-        self.l_paren(&arg.l_paren);
-        self.always_ff_clock(&arg.always_ff_clock);
-        if let Some(ref x) = arg.always_ff_event_list_opt {
-            if self.always_ff_reset_exist_in_sensitivity_list(&x.always_ff_reset) {
-                self.comma(&x.comma);
-                self.space(1);
-            }
-            self.always_ff_reset(&x.always_ff_reset);
-        }
-        self.r_paren(&arg.r_paren);
-    }
-
     /// Semantic action for non-terminal 'AlwaysFfClock'
     fn always_ff_clock(&mut self, arg: &AlwaysFfClock) {
         if let Ok(found) = symbol_table::resolve(arg.hierarchical_identifier.as_ref()) {

testcases/sv/12_always.sv

@@ -4,6 +4,15 @@ module veryl_testcase_Module12_1 (
 );
     logic a;
     logic b;
+    logic c;
+
+    always_ff @ (posedge i_clk, negedge i_rst_n) begin
+        if (!i_rst_n) begin
+            c <= 0;
+        end else begin
+            c <= ~a;
+        end
+    end
 
     always_ff @ (posedge i_clk, negedge i_rst_n) begin
         if (!i_rst_n) begin

testcases/veryl/12_always.veryl

@@ -4,6 +4,15 @@ module Module12_1 (
 ) {
     var a: logic;
     var b: logic;
+    var c: logic;
+
+    always_ff (i_clk) {
+        if_reset {
+            c = 0;
+        } else {
+            c = ~a;
+        }
+    }
 
     always_ff {
         if_reset {