Add regression tests for prefix labels on procedural blocks

Check the reproducer from GitHub issue #1321, which uses a prefix label on a
begin-end block inside an `always_comb` process.

Check prefix labels on sequential and parallel blocks. Place attributes between
the labels and block keywords, verify that the sequential label creates a named
scope, cover all fork join types, and use matching closing labels.

Check separately that visible type identifiers can be shadowed by prefix labels
on sequential and parallel blocks.

Check that matching and different block names after `begin` or `fork` are
rejected when a prefix label is already present.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>

ivtest/ivltests/br_gh1321.v

@@ -0,0 +1,18 @@
+module test;
+  logic a;
+
+  always_comb begin
+    my_blk: begin
+      a = 1'b1;
+    end
+  end
+
+  initial begin
+    #1;
+    if (a !== 1'b1) begin
+      $display("FAILED(%0d). Expected 1, got %b", `__LINE__, a);
+    end else begin
+      $display("PASSED");
+    end
+  end
+endmodule

ivtest/ivltests/sv_block_prefix_label.v

@@ -0,0 +1,29 @@
+// Check that sequential block prefix labels work.
+
+module test;
+
+  reg failed;
+  reg value;
+
+  initial begin
+    failed = 1'b0;
+    value = 1'b0;
+
+    BLOCK_LABEL: (* keep = 1 *) begin
+      value = 1'b1;
+      disable BLOCK_LABEL;
+      value = 1'b0;
+    end : BLOCK_LABEL
+
+    if (value !== 1'b1) begin
+      $display("FAILED(%0d). Block prefix label did not create a named scope",
+               `__LINE__);
+      failed = 1'b1;
+    end
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_block_prefix_name_diff_fail.v

@@ -0,0 +1,6 @@
+// Check that different prefix and post-begin labels are rejected.
+
+module test;
+  initial LABEL_A: begin : LABEL_B
+  end
+endmodule

ivtest/ivltests/sv_block_prefix_name_same_fail.v

@@ -0,0 +1,6 @@
+// Check that matching prefix and post-begin labels are rejected.
+
+module test;
+  initial LABEL: begin : LABEL
+  end
+endmodule

ivtest/ivltests/sv_fork_prefix_label.v

@@ -0,0 +1,36 @@
+// Check that fork prefix labels work with all join types.
+
+module test;
+
+  reg failed;
+  reg [2:0] value;
+
+  initial begin
+    failed = 1'b0;
+    value = 3'b000;
+
+    FORK_LABEL: (* keep = 1 *) fork
+      value[0] = 1'b1;
+    join : FORK_LABEL
+
+    FORK_ANY_LABEL: (* keep = 1 *) fork
+      value[1] = 1'b1;
+    join_any : FORK_ANY_LABEL
+
+    FORK_NONE_LABEL: (* keep = 1 *) fork
+      value[2] = 1'b1;
+    join_none : FORK_NONE_LABEL
+    wait fork;
+
+    if (value !== 3'b111) begin
+      $display("FAILED(%0d). Fork prefix labels did not execute all blocks",
+               `__LINE__);
+      failed = 1'b1;
+    end
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_fork_prefix_name_diff_fail.v

@@ -0,0 +1,6 @@
+// Check that different prefix and post-fork labels are rejected.
+
+module test;
+  initial LABEL_A: fork : LABEL_B
+  join
+endmodule

ivtest/ivltests/sv_fork_prefix_name_same_fail.v

@@ -0,0 +1,6 @@
+// Check that matching prefix and post-fork labels are rejected.
+
+module test;
+  initial LABEL: fork : LABEL
+  join
+endmodule

ivtest/ivltests/sv_type_identifier_block_prefix_label_name.v

@@ -0,0 +1,29 @@
+// Check that sequential block prefix labels can shadow type identifiers.
+
+typedef int T;
+
+module test;
+
+  reg failed;
+  reg value;
+
+  initial begin
+    failed = 1'b0;
+    value = 1'b0;
+
+    T: begin
+      value = 1'b1;
+    end : T
+
+    if (value !== 1'b1) begin
+      $display("FAILED(%0d). Block prefix label did not hide typedef",
+               `__LINE__);
+      failed = 1'b1;
+    end
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_type_identifier_fork_prefix_label_name.v

@@ -0,0 +1,29 @@
+// Check that fork prefix labels can shadow type identifiers.
+
+typedef int T;
+
+module test;
+
+  reg failed;
+  reg value;
+
+  initial begin
+    failed = 1'b0;
+    value = 1'b0;
+
+    T: fork
+      value = 1'b1;
+    join : T
+
+    if (value !== 1'b1) begin
+      $display("FAILED(%0d). Fork prefix label did not hide typedef",
+               `__LINE__);
+      failed = 1'b1;
+    end
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule

ivtest/regress-vvp.list

@@ -82,6 +82,7 @@ br_gh1256b			vvp_tests/br_gh1256b.json
 br_gh1258a			vvp_tests/br_gh1258a.json
 br_gh1258b			vvp_tests/br_gh1258b.json
 br_gh1286			vvp_tests/br_gh1286.json
+br_gh1321			vvp_tests/br_gh1321.json
 br_gh1323			vvp_tests/br_gh1323.json
 br_gh1384			vvp_tests/br_gh1384.json
 br_gh1385			vvp_tests/br_gh1385.json
@@ -264,6 +265,9 @@ sv_array_cassign_single_fail1	vvp_tests/sv_array_cassign_single_fail1.json
 sv_assign_pattern_auto_force_fail	vvp_tests/sv_assign_pattern_auto_force_fail.json
 sv_automatic_2state		vvp_tests/sv_automatic_2state.json
 sv_bad_member_lval_proc_fail	vvp_tests/sv_bad_member_lval_proc_fail.json
+sv_block_prefix_label			vvp_tests/sv_block_prefix_label.json
+sv_block_prefix_name_diff_fail		vvp_tests/sv_block_prefix_name_diff_fail.json
+sv_block_prefix_name_same_fail		vvp_tests/sv_block_prefix_name_same_fail.json
 sv_byte_array_string1		vvp_tests/sv_byte_array_string1.json
 sv_byte_array_string2		vvp_tests/sv_byte_array_string2.json
 sv_byte_array_string3		vvp_tests/sv_byte_array_string3.json
@@ -315,6 +319,9 @@ sv_default_port_value2		vvp_tests/sv_default_port_value2.json
 sv_default_port_value3		vvp_tests/sv_default_port_value3.json
 sv_foreach9			vvp_tests/sv_foreach9.json
 sv_foreach10			vvp_tests/sv_foreach10.json
+sv_fork_prefix_label			vvp_tests/sv_fork_prefix_label.json
+sv_fork_prefix_name_diff_fail		vvp_tests/sv_fork_prefix_name_diff_fail.json
+sv_fork_prefix_name_same_fail		vvp_tests/sv_fork_prefix_name_same_fail.json
 sv_interface			vvp_tests/sv_interface.json
 sv_interface_identifier_block_name	vvp_tests/sv_interface_identifier_block_name.json
 sv_interface_identifier_instance_name	vvp_tests/sv_interface_identifier_instance_name.json
@@ -411,6 +418,7 @@ sv_type_identifier_assert_label	vvp_tests/sv_type_identifier_assert_label.json
 sv_type_identifier_attribute_name	vvp_tests/sv_type_identifier_attribute_name.json
 sv_type_identifier_attribute_target	vvp_tests/sv_type_identifier_attribute_target.json
 sv_type_identifier_block_label_name	vvp_tests/sv_type_identifier_block_label_name.json
+sv_type_identifier_block_prefix_label_name	vvp_tests/sv_type_identifier_block_prefix_label_name.json
 sv_type_identifier_config_name	vvp_tests/sv_type_identifier_config_name.json
 sv_type_identifier_discipline_name	vvp_tests/sv_type_identifier_discipline_name.json
 sv_type_identifier_discipline_nature_ref	vvp_tests/sv_type_identifier_discipline_nature_ref.json
@@ -420,6 +428,7 @@ sv_type_identifier_for_name	vvp_tests/sv_type_identifier_for_name.json
 sv_type_identifier_foreach_array_name	vvp_tests/sv_type_identifier_foreach_array_name.json
 sv_type_identifier_foreach_name	vvp_tests/sv_type_identifier_foreach_name.json
 sv_type_identifier_fork_label_name	vvp_tests/sv_type_identifier_fork_label_name.json
+sv_type_identifier_fork_prefix_label_name	vvp_tests/sv_type_identifier_fork_prefix_label_name.json
 sv_type_identifier_function_name	vvp_tests/sv_type_identifier_function_name.json
 sv_type_identifier_generate_label_name	vvp_tests/sv_type_identifier_generate_label_name.json
 sv_type_identifier_genvar_name	vvp_tests/sv_type_identifier_genvar_name.json

ivtest/vvp_tests/br_gh1321.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "normal",
+    "source"        : "br_gh1321.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_block_prefix_label.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "normal",
+    "source"        : "sv_block_prefix_label.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_block_prefix_name_diff_fail.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "CE",
+    "source"        : "sv_block_prefix_name_diff_fail.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_block_prefix_name_same_fail.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "CE",
+    "source"        : "sv_block_prefix_name_same_fail.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_fork_prefix_label.json

@@ -0,0 +1,9 @@
+{
+    "type"          : "normal",
+    "source"        : "sv_fork_prefix_label.v",
+    "iverilog-args" : [ "-g2005-sv" ],
+    "vlog95" : {
+        "__comment" : "join_any, join_none, and wait fork are not supported",
+        "type"      : "CE"
+    }
+}

ivtest/vvp_tests/sv_fork_prefix_name_diff_fail.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "CE",
+    "source"        : "sv_fork_prefix_name_diff_fail.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_fork_prefix_name_same_fail.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "CE",
+    "source"        : "sv_fork_prefix_name_same_fail.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_type_identifier_block_prefix_label_name.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "normal",
+    "source"        : "sv_type_identifier_block_prefix_label_name.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}

ivtest/vvp_tests/sv_type_identifier_fork_prefix_label_name.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "normal",
+    "source"        : "sv_type_identifier_fork_prefix_label_name.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}