From 5d630f7ebe98fc4fe96706ca4b79e3f80c9e91bf Mon Sep 17 00:00:00 2001
From: Nick Gasson <nick@nickg.me.uk>
Date: Sun, 11 Jul 2021 09:29:07 +0800
Subject: [PATCH] Fix signal3 case

---
 src/elab.c       |  9 ++++++---
 src/enode.c      |  3 +++
 test/test_elab.c | 31 +++++++++++++++++++++++++++++--
 3 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/src/elab.c b/src/elab.c
index 9d62b4a5..a48b308f 100644
--- a/src/elab.c
+++ b/src/elab.c
@@ -2503,8 +2503,11 @@ static void drv_add(int op, vcode_reg_t target, unsigned count,
             drive = n;
          }
          else if (offset > o && offset < o + length) {
-            printf("need to split nexus %d for offset %d\n", i, offset);
+            printf("need to split nexus %d for offset %d length %d o %d\n", i,
+                   offset, length, o);
             drive = e_split_nexus(ctx->root, n, offset - o);
+            if (length - offset + o > count)
+               e_split_nexus(ctx->root, drive, count);
          }
          else if (offset + length < o)
             break;
@@ -2518,8 +2521,8 @@ static void drv_add(int op, vcode_reg_t target, unsigned count,
                have = e_nexus(proc, j) == n;
 
             if (!have) {
-               e_add_nexus(proc, n);
-               e_add_proc(n, proc);
+               e_add_nexus(proc, drive);
+               e_add_proc(drive, proc);
             }
          }
       }
diff --git a/src/enode.c b/src/enode.c
index fbcba5a0..7acca686 100644
--- a/src/enode.c
+++ b/src/enode.c
@@ -389,10 +389,13 @@ e_node_t e_split_nexus(e_node_t root, e_node_t orig, unsigned width)
 {
    assert(root->object.kind == E_ROOT);
    assert(orig->object.kind == E_NEXUS);
+   assert(width > 0);
 
    const unsigned owidth = e_width(orig);
    e_slice_t oslice = e_slice(orig);
 
+   assert(width < owidth);
+
    e_node_t new = e_new(E_NEXUS);
    e_set_ident(new, e_ident(orig));
    e_set_width(new, owidth - width);
diff --git a/test/test_elab.c b/test/test_elab.c
index 8b571e71..6c9ecc16 100644
--- a/test/test_elab.c
+++ b/test/test_elab.c
@@ -181,8 +181,6 @@ START_TEST(test_elab3)
    e_node_t e = run_elab();
    check_elab(e);
 
-   e_dump(e);
-
    e_node_t n0 = e_nexus(e, 0);
    fail_unless(e_pos(n0) == 0);
    fail_unless(e_width(n0) == 4);
@@ -882,6 +880,34 @@ START_TEST(test_arrayref1)
 
    const int nnexus = e_nexuses(root);
    ck_assert_int_eq(nnexus, 16);   // Would have been 15 with old grouping code
+
+   // TODO: detailed checking here
+}
+END_TEST
+
+START_TEST(test_signal3)
+{
+   input_from_file(TESTDIR "/group/signal3.vhd");
+
+   e_node_t root = run_elab();
+   check_elab(root);
+
+   e_dump(root);
+
+   e_node_t proc1 = e_proc(e_scope(root, 0), 0);
+   e_node_t proc2 = e_proc(e_scope(root, 0), 1);
+
+   ck_assert_int_eq(e_nexuses(root), 4);
+   fail_unless(e_width(e_nexus(root, 0)) == 1);
+   fail_unless(e_procs(e_nexus(root, 0)) == 0);
+   fail_unless(e_width(e_nexus(root, 1)) == 1);
+   fail_unless(e_procs(e_nexus(root, 1)) == 1);
+   fail_unless(e_proc(e_nexus(root, 1), 0) == proc1);
+   fail_unless(e_width(e_nexus(root, 2)) == 1);
+   fail_unless(e_procs(e_nexus(root, 2)) == 0);
+   fail_unless(e_width(e_nexus(root, 3)) == 1);
+   fail_unless(e_procs(e_nexus(root, 3)) == 1);
+   fail_unless(e_proc(e_nexus(root, 3), 0) == proc2);
 }
 END_TEST
 
@@ -940,6 +966,7 @@ Suite *get_elab_tests(void)
 
    TCase *tc_group = nvc_unit_test("group");
    tcase_add_test(tc_group, test_arrayref1);
+   tcase_add_test(tc_group, test_signal3);
    suite_add_tcase(s, tc_group);
 
    return s;
-- 
2.39.2