From edfb1489c44f473f4d9924a02d562c95edefb9f6 Mon Sep 17 00:00:00 2001
From: Sean Anderson <sean.anderson@seco.com>
Date: Mon, 22 May 2023 12:01:38 -0400
Subject: [PATCH] Fix coverage generation for unary operators

Unary functions (such as reductions) cause an assertion failure in
lower_logic_expr_coverage. As they operate on arrays, and arrays are
skipped anyway, modify this function to skip such operators. Also remove
a debug print while we're here.

Add a test case to ensure such functions are excluded from coverage.

Closes: #698
---
 src/lower.c                   | 13 ++++---------
 test/regress/cover16.sh       | 12 ++++++++++++
 test/regress/cover16.vhd      | 26 ++++++++++++++++++++++++++
 test/regress/gold/cover16.txt |  7 +++++++
 test/regress/testlist.txt     |  1 +
 5 files changed, 50 insertions(+), 9 deletions(-)
 create mode 100755 test/regress/cover16.sh
 create mode 100644 test/regress/cover16.vhd
 create mode 100644 test/regress/gold/cover16.txt

diff --git a/src/lower.c b/src/lower.c
index 78c3d503..2ba27e5d 100644
--- a/src/lower.c
+++ b/src/lower.c
@@ -1913,23 +1913,18 @@ static vcode_reg_t lower_logic_expr_coverage_for(tree_t fcall,
 static void lower_logic_expr_coverage(lower_unit_t *lu, tree_t fcall,
                                       tree_t decl, vcode_reg_t *args)
 {
-   fmt_loc(stdout, tree_loc(decl));
-
    unsigned flags = cover_get_std_log_expr_flags(decl);
    if (!flags)
       return;
 
    flags |= COV_FLAG_EXPR_STD_LOGIC;
 
-   assert(tree_params(fcall) == 2);
-
-   bool is_array[2] = {
-      type_is_array(type_param(tree_type(decl), 0)),
-      type_is_array(type_param(tree_type(decl), 1))
-   };
+   if (tree_params(fcall) != 2)
+      return;
 
    // Skip arrays -> Matches behavior of VCS and Modelsim
-   if (is_array[0] || is_array[1])
+   if (type_is_array(type_param(tree_type(decl), 0)) ||
+       type_is_array(type_param(tree_type(decl), 1)))
       return;
 
    vcode_reg_t mask =
diff --git a/test/regress/cover16.sh b/test/regress/cover16.sh
new file mode 100755
index 00000000..aa87f722
--- /dev/null
+++ b/test/regress/cover16.sh
@@ -0,0 +1,12 @@
+set -xe
+
+pwd
+which nvc
+
+nvc --std=2019 -a $TESTDIR/regress/cover16.vhd -e --cover cover16 -r
+nvc -c --report html work/_WORK.COVER16.elab.covdb  2>&1 | tee out.txt
+
+# Adjust output to be work directory relative
+sed -i -e "s/[^ ]*regress\/data\//data\//g" out.txt
+
+diff -u $TESTDIR/regress/gold/cover16.txt out.txt
diff --git a/test/regress/cover16.vhd b/test/regress/cover16.vhd
new file mode 100644
index 00000000..aab9cd5d
--- /dev/null
+++ b/test/regress/cover16.vhd
@@ -0,0 +1,26 @@
+library ieee;
+use ieee.std_logic_1164.all;
+
+entity cover16 is
+end cover16;
+
+architecture test of cover16 is
+    signal a, b: std_logic := '0';
+    signal c, d: std_logic_vector(7 downto 0) := X"00";
+begin
+
+    process begin
+        c <= d and d;
+        wait for 1 ns;
+        c <= b and d;
+        wait for 1 ns;
+        c <= d and b;
+        wait for 1 ns;
+        a <= and d;
+        wait for 1 ns;
+        -- Ensure we have at least one covered expression
+        a <= '1' and b;
+        wait;
+    end process;
+
+end architecture;
diff --git a/test/regress/gold/cover16.txt b/test/regress/gold/cover16.txt
new file mode 100644
index 00000000..dbb96dbb
--- /dev/null
+++ b/test/regress/gold/cover16.txt
@@ -0,0 +1,7 @@
+** Note: Code coverage report folder: html.
+** Note: Code coverage report contains: covered, uncovered, excluded coverage details.
+** Note: code coverage results for: WORK.COVER16
+** Note:      statement:     100.0 % (10/10)
+** Note:      branch:        N.A.
+** Note:      toggle:        N.A.
+** Note:      expression:    33.3 % (1/3)
diff --git a/test/regress/testlist.txt b/test/regress/testlist.txt
index 0877df0b..7de69223 100644
--- a/test/regress/testlist.txt
+++ b/test/regress/testlist.txt
@@ -781,3 +781,4 @@ func23          normal,2019
 protected9      normal,2019
 func24          normal,2019
 vhpi6           normal,vhpi
+cover16         cover,shell
-- 
2.39.2