Add regression test for $bits() on array identifiers

Check that for array identifiers $bits() includes the total size of the
signal.

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

ivtest/ivltests/bits4.v

@@ -0,0 +1,37 @@
+// Check that passing a array identifiers and array slices to $bits works as expected
+
+module test;
+
+  bit failed = 1'b0;
+
+  `define check(expr, value) do begin \
+    if ($bits(expr) !== value) begin \
+      $display("FAILED(%d): $bits(", `"expr`", ") is %0d", `__LINE__, $bits(expr), " expected %0d", value); \
+      failed = 1'b1; \
+    end \
+  end while (0)
+
+  typedef bit T[3:0];
+
+  T x;
+  byte y[7:0][2:0];
+
+  initial begin
+    integer i;
+    i = 4;
+
+    `check(x, 4);
+    `check(y, $bits(byte) * 3 * 8);
+    `check(y[0], $bits(byte) * 3);
+    `check(y[1:0], $bits(byte) * 3 * 2);
+    `check(y[1+:3], $bits(byte) * 3 * 3);
+    `check(y[4-:4], $bits(byte) * 3 * 4);
+    `check(y[i-:2], $bits(byte) * 3 * 2);
+    `check(y[i+:2], $bits(byte) * 3 * 2);
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule

ivtest/regress-vvp.list

@@ -3,6 +3,7 @@
 # describes the test.
 
 array_packed_write_read		vvp_tests/array_packed_write_read.json
+bits4				vvp_tests/bits4.json
 bitsel11			vvp_tests/bitsel11.json
 br_gh13a			vvp_tests/br_gh13a.json
 br_gh13a-vlog95			vvp_tests/br_gh13a-vlog95.json

ivtest/vvp_tests/bits4.json

@@ -0,0 +1,5 @@
+{
+    "type"          : "normal",
+    "source"        : "bits4.v",
+    "iverilog-args" : [ "-g2005-sv" ]
+}