WIP

nickg · Jul 25, 2023 · 6a84191 · 6a84191
1 parent 9ca6ee7
commit 6a84191
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Showing 5 changed files with 78 additions and 30 deletions.
diff --git a/src/eval.c b/src/eval.c
@@ -239,7 +239,7 @@ bool eval_possible(tree_t t, unit_registry_t *ur)
             if (tree_has_value(decl))
                return eval_possible(tree_value(decl), ur);
             else
-               return true;
+               return false;
 
          default:
             return eval_not_possible(t, "reference");

diff --git a/src/lower.c b/src/lower.c
@@ -2698,11 +2698,37 @@ static vcode_reg_t lower_link_var(lower_unit_t *lu, tree_t decl)
                      istr(tree_ident(decl)));
       }
    }
-   else if (mode == LOWER_THUNK && lu->parent == NULL
-            && !arena_frozen(tree_arena(container))) {
+   else if (mode == LOWER_THUNK && lu->parent == NULL) {
       // Handle a special case of simplifying locally static expressions
       // that reference constant declarations
-      return lower_rvalue(lu, tree_value(decl));
+      assert(tree_kind(decl) == T_CONST_DECL);
+
+      type_t type = tree_type(decl);
+      tree_t value = tree_value(decl);
+      vcode_reg_t value_reg = lower_rvalue(lu, value), ptr_reg;
+
+      switch (vcode_reg_kind(value_reg)) {
+      case VCODE_TYPE_POINTER:
+      case VCODE_TYPE_UARRAY:
+         ptr_reg = value_reg;
+         break;
+      default:
+         {
+            vcode_type_t vtype = lower_type(type);
+            vcode_type_t vbounds = lower_bounds(type);
+            vcode_var_t var = emit_var(vtype, vbounds, tree_ident(decl), 0);
+            lower_put_vcode_obj(decl, var, lu);
+            emit_store(value_reg, var);
+
+            ptr_reg = emit_index(var, VCODE_INVALID_REG);
+         }
+         break;
+      }
+
+      if (type_is_array(type))
+         return lower_coerce_arrays(lu, tree_type(value), type, ptr_reg);
+      else
+         return ptr_reg;
    }
 
    assert(!is_uninstantiated_package(container));

diff --git a/test/simp/issue742.vhd b/test/simp/issue742.vhd
@@ -0,0 +1,24 @@
+PACKAGE tb_test_package IS
+
+	CONSTANT C_VEC    : bit_vector(2 DOWNTO 0) := "111";
+
+	PROCEDURE test (
+		o: OUT bit
+	);
+
+END PACKAGE tb_test_package;
+
+PACKAGE BODY tb_test_package IS
+
+	PROCEDURE test (
+		o: OUT bit
+	) IS
+	BEGIN
+		IF C_VEC /= "000" THEN
+			o := '1';
+		ELSE
+			o := '0';
+		END IF;
+	END test;
+
+END PACKAGE BODY tb_test_package;
diff --git a/test/test_lower.c b/test/test_lower.c
@@ -2702,8 +2702,9 @@ START_TEST(test_thunk)
       vcode_select_unit(t0);
 
       EXPECT_BB(0) = {
-         { VCODE_OP_PACKAGE_INIT, .name = "WORK.PACK" },
-         { VCODE_OP_LINK_VAR, .name = "C" },
+         { VCODE_OP_CONST, .value = 1 },
+         { VCODE_OP_CONST_ARRAY, .length = 4 },
+         { VCODE_OP_ADDRESS_OF },
          { VCODE_OP_CONST, .value = 2 },
          { VCODE_OP_ARRAY_REF },
          { VCODE_OP_LOAD_INDIRECT },
@@ -2715,29 +2716,6 @@ START_TEST(test_thunk)
 
       vcode_unit_unref(t0);
    }
-
-   {
-      vcode_unit_t t1 = lower_thunk(NULL, tree_value(tree_decl(arch, 1)));
-      fail_if(t1 == NULL);
-      vcode_select_unit(t1);
-
-      EXPECT_BB(0) = {
-         { VCODE_OP_PACKAGE_INIT, .name = "WORK.PACK" },
-         { VCODE_OP_LINK_VAR, .name = "D" },
-         { VCODE_OP_CONST, .value = 0 },
-         { VCODE_OP_CONST, .value = 1 },
-         { VCODE_OP_ARRAY_REF },
-         { VCODE_OP_RECORD_REF, .field = 0 },
-         { VCODE_OP_LOAD_INDIRECT },
-         { VCODE_OP_DEBUG_LOCUS },
-         { VCODE_OP_TRAP_ADD },
-         { VCODE_OP_RETURN },
-      };
-
-      CHECK_BB(0);
-
-      vcode_unit_unref(t1);
-   }
 }
 END_TEST
 

diff --git a/test/test_simp.c b/test/test_simp.c
@@ -1380,7 +1380,11 @@ START_TEST(test_genpack1)
 
    tree_t b0 = tree_stmt(top, 0);
    fail_unless(tree_kind(b0) == T_BLOCK);
-   fail_unless(tree_stmts(b0) == 0);
+   fail_unless(tree_stmts(b0) == 1);
+
+   tree_t p1 = tree_stmt(b0, 0);
+   fail_unless(tree_kind(p1) == T_PROCESS);
+   fail_unless(tree_stmts(p1) == 2);   // Should have been eliminated
 
    fail_if_errors();
 }
@@ -1520,6 +1524,21 @@ START_TEST(test_ieee1)
 }
 END_TEST
 
+START_TEST(test_issue742)
+{
+   input_from_file(TESTDIR "/simp/issue742.vhd");
+
+   tree_t b = parse_check_and_simplify(T_PACKAGE, T_PACK_BODY);
+
+   tree_t test = tree_decl(b, 0);
+   fail_unless(tree_kind(test) == T_PROC_BODY);
+   fail_unless(tree_stmts(test) == 1);
+   fail_unless(tree_kind(tree_stmt(test, 0)) == T_VAR_ASSIGN);
+
+   fail_if_errors();
+}
+END_TEST
+
 Suite *get_simp_tests(void)
 {
    Suite *s = suite_create("simplify");
@@ -1578,6 +1597,7 @@ Suite *get_simp_tests(void)
    tcase_add_test(tc_core, test_casegen);
    tcase_add_test(tc_core, test_condexpr);
    tcase_add_test(tc_core, test_ieee1);
+   tcase_add_test(tc_core, test_issue742);
    suite_add_tcase(s, tc_core);
 
    return s;