Parse Verilog concatenation

src/vlog/vlog-dump.c

@@ -521,6 +521,19 @@ static void vlog_dump_cond_expr(vlog_node_t v, int indent)
    vlog_dump(vlog_right(v), 0);
 }
 
+static void vlog_dump_concat(vlog_node_t v, int indent)
+{
+   print_syntax("{");
+
+   const int nparams = vlog_params(v);
+   for (int i = 0; i < nparams; i++) {
+      if (i > 0) print_syntax(", ");
+      vlog_dump(vlog_param(v, i), 0);
+   }
+
+   print_syntax("}");
+}
+
 void vlog_dump(vlog_node_t v, int indent)
 {
    switch (vlog_kind(v)) {
@@ -631,6 +644,9 @@ void vlog_dump(vlog_node_t v, int indent)
    case V_COND_EXPR:
       vlog_dump_cond_expr(v, indent);
       break;
+   case V_CONCAT:
+      vlog_dump_concat(v, indent);
+      break;
    default:
       print_syntax("\n");
       fflush(stdout);

src/vlog/vlog-node.c

@@ -171,6 +171,9 @@ static const imask_t has_map[V_LAST_NODE_KIND] = {
 
    // V_REAL
    (I_DVAL),
+
+   // V_CONCAT
+   (I_PARAMS),
 };
 
 static const char *kind_text_map[V_LAST_NODE_KIND] = {
@@ -186,7 +189,7 @@ static const char *kind_text_map[V_LAST_NODE_KIND] = {
    "V_UNION_DECL", "V_STRUCT_DECL", "V_EVENT_CONTROL", "V_EMPTY",
    "V_REPEAT",     "V_WHILE",       "V_DO_WHILE",      "V_TASK_DECL",
    "V_FUNC_DECL",  "V_WAIT",        "V_PARAM_DECL",    "V_COND_EXPR",
-   "V_REAL",
+   "V_REAL",       "V_CONCAT",
 };
 
 static const change_allowed_t change_allowed[] = {

src/vlog/vlog-node.h

@@ -93,6 +93,7 @@ typedef enum {
    V_PARAM_DECL,
    V_COND_EXPR,
    V_REAL,
+   V_CONCAT,
 
    V_LAST_NODE_KIND
 } vlog_kind_t;

src/vlog/vlog-parse.c

@@ -1156,6 +1156,26 @@ static vlog_node_t p_mintypmax_expression(void)
    return p_expression();
 }
 
+static vlog_node_t p_concatenation(void)
+{
+   // { expression { , expression } }
+
+   BEGIN("concatenation");
+
+   consume(tLBRACE);
+
+   vlog_node_t v = vlog_new(V_CONCAT);
+
+   do {
+      vlog_add_param(v, p_expression());
+   } while (optional(tCOMMA));
+
+   consume(tRBRACE);
+
+   vlog_set_loc(v, CURRENT_LOC);
+   return v;
+}
+
 static vlog_node_t p_primary(void)
 {
    // primary_literal | empty_queue
@@ -1186,8 +1206,11 @@ static vlog_node_t p_primary(void)
          consume(tRPAREN);
          return expr;
       }
+   case tLBRACE:
+      return p_concatenation();
    default:
-      one_of(tID, tSTRING, tNUMBER, tUNSIGNED, tREAL, tSYSTASK, tLPAREN);
+      one_of(tID, tSTRING, tNUMBER, tUNSIGNED, tREAL, tSYSTASK, tLPAREN,
+             tLBRACE);
       return p_select(error_marker());
    }
 }
@@ -1255,9 +1278,10 @@ static vlog_node_t p_nonbinary_expression(void)
    case tSTRING:
    case tNUMBER:
    case tUNSIGNED:
+   case tREAL:
    case tSYSTASK:
    case tLPAREN:
-   case tREAL:
+   case tLBRACE:
       return p_primary();
    case tMINUS:
    case tTILDE:
@@ -1270,7 +1294,8 @@ static vlog_node_t p_nonbinary_expression(void)
          return v;
       }
    default:
-      one_of(tID, tSTRING, tNUMBER, tUNSIGNED, tMINUS, tTILDE, tBANG, tSYSTASK);
+      one_of(tID, tSTRING, tNUMBER, tUNSIGNED, tREAL, tSYSTASK, tLPAREN,
+             tLBRACE, tMINUS, tTILDE, tBANG);
       return p_select(error_marker());
    }
 }
@@ -1493,11 +1518,25 @@ static vlog_node_t p_net_lvalue(void)
 
    BEGIN("net lvalue");
 
-   ident_t id = p_identifier();
-   vlog_node_t v = p_constant_select(id);
+   if (optional(tLBRACE)) {
+      vlog_node_t v = vlog_new(V_CONCAT);
 
-   vlog_set_loc(v, CURRENT_LOC);
-   return v;
+      do {
+         vlog_add_param(v, p_net_lvalue());
+      } while (optional(tCOMMA));
+
+      consume(tRBRACE);
+
+      vlog_set_loc(v, CURRENT_LOC);
+      return v;
+   }
+   else {
+      ident_t id = p_identifier();
+      vlog_node_t v = p_constant_select(id);
+
+      vlog_set_loc(v, CURRENT_LOC);
+      return v;
+   }
 }
 
 static vlog_node_t p_operator_assignment(vlog_node_t lhs)

src/vlog/vlog-pp.l

@@ -103,6 +103,8 @@ ID    [a-zA-Z_]([a-zA-Z0-9_$])*
 `timescale              |
 `resetall               |
 `pragma                 |
+`begin_keywords         |
+`end_keywords           |
 `celldefine             |
 `endcelldefine          { tb_cat(output, vlogpp_text); }
 

src/vlog/vlog-sem.c

@@ -244,6 +244,40 @@ static void vlog_check_bassign(vlog_node_t stmt)
    vlog_check_variable_target(target);
 }
 
+static void vlog_check_net_lvalue(vlog_node_t v, vlog_node_t where)
+{
+   switch (vlog_kind(v)) {
+   case V_NET_DECL:
+      break;
+   case V_PORT_DECL:
+      if (vlog_has_ref(v))
+         vlog_check_net_lvalue(vlog_ref(v), where);
+      break;
+   case V_BIT_SELECT:
+   case V_REF:
+      if (vlog_has_ref(v))
+         vlog_check_net_lvalue(vlog_ref(v), v);
+      break;
+   case V_CONCAT:
+      {
+         const int nparams = vlog_params(v);
+         for (int i = 0; i < nparams; i++) {
+            vlog_node_t p = vlog_param(v, i);
+            vlog_check_net_lvalue(p, p);
+         }
+      }
+      break;
+   default:
+      {
+         diag_t *d = diag_new(DIAG_ERROR, vlog_loc(where));
+         name_for_diag(d, where, "target");
+         diag_suppress(d, has_error(where));
+         diag_printf(d, " cannot be driven by continuous assignment");
+         diag_emit(d);
+      }
+   }
+}
+
 static void vlog_check_assign(vlog_node_t stmt)
 {
    vlog_node_t target = vlog_target(stmt);
@@ -252,13 +286,7 @@ static void vlog_check_assign(vlog_node_t stmt)
    vlog_node_t value = vlog_value(stmt);
    vlog_check(value);
 
-   if (!vlog_is_net(target)) {
-      diag_t *d = diag_new(DIAG_ERROR, vlog_loc(target));
-      name_for_diag(d, target, "target");
-      diag_suppress(d, has_error(target));
-      diag_printf(d, " cannot be driven by continuous assignment");
-      diag_emit(d);
-   }
+   vlog_check_net_lvalue(target, target);
 }
 
 static void vlog_check_timing(vlog_node_t timing)
@@ -613,6 +641,15 @@ static void vlog_check_cond_expr(vlog_node_t expr)
    vlog_check(vlog_right(expr));
 }
 
+static void vlog_check_concat(vlog_node_t expr)
+{
+   const int nparams = vlog_params(expr);
+   for (int i = 0; i < nparams; i++) {
+      vlog_node_t p = vlog_param(expr, i);
+      vlog_check(p);
+   }
+}
+
 void vlog_check(vlog_node_t v)
 {
    switch (vlog_kind(v)) {
@@ -729,6 +766,9 @@ void vlog_check(vlog_node_t v)
    case V_COND_EXPR:
       vlog_check_cond_expr(v);
       break;
+   case V_CONCAT:
+      vlog_check_concat(v);
+      break;
    default:
       fatal_at(vlog_loc(v), "cannot check verilog node %s",
                vlog_kind_str(vlog_kind(v)));

test/dump/vlog1.v

@@ -50,5 +50,6 @@ module mod3;   // Check operator precedence
   end
   real v1 = 1.5;
   integer v2 = x ? 1 : 2;
+  assign z = {x, y};
 endmodule // mod3
 

test/run_ivtest.rb

@@ -18,7 +18,7 @@
 IvtestDir = Pathname.new(ARGV[0]).realpath
 GitRev = IO::popen("git rev-parse --short HEAD").read.chomp
 Tool = ENV['NVC'] || 'nvc'
-ExpectFails = 1324
+ExpectFails = 1280
 
 ENV['NVC_COLORS'] = 'always'
 

test/test_dump.c

@@ -564,6 +564,7 @@ START_TEST(test_vlog1)
              "    if ((x == y) || (y == z));\n"
              "    if ((x & y) == z);\n"
              "  end\n"
+             "  assign z = {x, y};\n"
              "endmodule // mod3\n\n");
    tb_rewind(tb);
 

test/test_vlog.c

@@ -169,7 +169,7 @@ START_TEST(test_parse1)
    vlog_node_t m = vlog_parse();
    fail_if(m == NULL);
    fail_unless(vlog_kind(m) == V_MODULE);
-   fail_unless(vlog_stmts(m) == 12);
+   fail_unless(vlog_stmts(m) == 14);
    fail_unless(vlog_ports(m) == 0);
    fail_unless(vlog_decls(m) == 14);
 
@@ -632,6 +632,28 @@ START_TEST(test_pp3)
 }
 END_TEST
 
+START_TEST(test_concat1)
+{
+   input_from_file(TESTDIR "/vlog/concat1.v");
+
+   const error_t expect[] = {
+      { 10, "'q' cannot be driven by continuous assignment" },
+      { -1, NULL }
+   };
+   expect_errors(expect);
+
+   vlog_node_t m = vlog_parse();
+   fail_if(m == NULL);
+   fail_unless(vlog_kind(m) == V_MODULE);
+
+   vlog_check(m);
+
+   fail_unless(vlog_parse() == NULL);
+
+   check_expected_errors();
+}
+END_TEST
+
 Suite *get_vlog_tests(void)
 {
    Suite *s = suite_create("vlog");
@@ -656,6 +678,7 @@ Suite *get_vlog_tests(void)
    tcase_add_test(tc, test_union1);
    tcase_add_test(tc, test_param1);
    tcase_add_test(tc, test_pp3);
+   tcase_add_test(tc, test_concat1);
    suite_add_tcase(s, tc);
 
    return s;

test/vlog/concat1.v

@@ -0,0 +1,12 @@
+module concat1;
+  wire       x, y;
+  wire [7:0] z;
+  real       r1;
+  reg        q;
+
+  assign a1 = {x, y};   // OK
+  assign a2 = {r1, x};  // Error
+  assign {z[0], z[4]} = {x, y};   // OK
+  assign {x, q} = 2'b11;  // Error
+
+endmodule // concat1

test/vlog/parse1.v

@@ -54,4 +54,6 @@ module parse1;
   real      r3 = 1.0;
   shortreal r4 = 6.7;
   realtime  r5 = 1.0;
+  assign r2 = {x, y};
+  assign {r1, r2} = {x, y};
 endmodule // parse1