From 4c14ee0cd0ea4b913304293250497c6232ac5703 Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Thu, 17 Aug 2023 22:33:40 +0100
Subject: [PATCH] Branch over concatenation in assert message

---
 src/lower.c            |  2 ++
 test/lower/assert2.vhd | 18 ++++++++++++++++++
 test/test_lower.c      | 20 ++++++++++++++++++++
 3 files changed, 40 insertions(+)
 create mode 100644 test/lower/assert2.vhd

diff --git a/src/lower.c b/src/lower.c
index be2542e73..090ce1643 100644
--- a/src/lower.c
+++ b/src/lower.c
@@ -1884,6 +1884,8 @@ static bool lower_side_effect_free(tree_t expr)
          if (kind == S_DIV || kind == S_DIV_PR || kind == S_DIV_RI
              || kind == S_REM || kind == S_MOD)
             return false;
+         else if (kind == S_CONCAT)
+            return false;   // Allocates memory
          else if (!is_builtin(kind))
             return false;
 
diff --git a/test/lower/assert2.vhd b/test/lower/assert2.vhd
new file mode 100644
index 000000000..c10c6d07f
--- /dev/null
+++ b/test/lower/assert2.vhd
@@ -0,0 +1,18 @@
+entity assert2 is
+end entity;
+
+architecture test of assert2 is
+    procedure test(x : integer; s : string) is
+    begin
+        assert x > 0 report "s=" & s;   -- Message has allocation side-effect
+    end procedure;
+begin
+
+    p1: process is
+        variable x : integer;
+    begin
+        test(-6, "hello");
+        wait;
+    end process;
+
+end architecture;
diff --git a/test/test_lower.c b/test/test_lower.c
index ddec455a0..53b3ca7f7 100644
--- a/test/test_lower.c
+++ b/test/test_lower.c
@@ -5241,6 +5241,25 @@ START_TEST(test_protpcall)
 }
 END_TEST
 
+START_TEST(test_assert2)
+{
+   input_from_file(TESTDIR "/lower/assert2.vhd");
+
+   run_elab();
+
+   vcode_unit_t vu = find_unit("WORK.ASSERT2.TEST(IS)");
+   vcode_select_unit(vu);
+
+   EXPECT_BB(0) = {
+      { VCODE_OP_CONST, .value = 0 },
+      { VCODE_OP_CMP, .cmp = VCODE_CMP_GT },
+      { VCODE_OP_COND, .target = 2, .target_else = 1 },
+   };
+
+   CHECK_BB(0);
+}
+END_TEST
+
 Suite *get_lower_tests(void)
 {
    Suite *s = suite_create("lower");
@@ -5368,6 +5387,7 @@ Suite *get_lower_tests(void)
    tcase_add_test(tc, test_issue725);
    tcase_add_test(tc, test_cond2);
    tcase_add_test(tc, test_protpcall);
+   tcase_add_test(tc, test_assert2);
    suite_add_tcase(s, tc);
 
    return s;