d: Fix associative array literals that don't have alignment holes filled

Associative array literal keys with alignment holes are now filled using
memset() prior to usage, with LTR evaluation of side-effects enforced.

gcc/d/ChangeLog:

	PR d/96152
	* d-codegen.cc (build_array_from_exprs): New function.
	* d-tree.h (build_array_from_exprs): Declare.
	* expr.cc (ExprVisitor::visit (AssocArrayLiteralExp *)): Use
	build_array_from_exprs to generate key and value arrays.

gcc/testsuite/ChangeLog:

	PR d/96152
	* gdc.dg/pr96152.d: New test.

gcc/d/d-codegen.cc

@@ -1722,6 +1722,42 @@ build_array_from_val (Type *type, tree val)
   return build_constructor (build_ctype (type), elms);
 }
 
+/* Build a static array of type TYPE from an array of EXPS.
+   If CONST_P is true, then all elements in EXPS are constants.  */
+
+tree
+build_array_from_exprs (Type *type, Expressions *exps, bool const_p)
+{
+  /* Build a CONSTRUCTOR from all expressions.  */
+  vec <constructor_elt, va_gc> *elms = NULL;
+  vec_safe_reserve (elms, exps->length);
+
+  Type *etype = type->nextOf ();
+  tree satype = make_array_type (etype, exps->length);
+
+  for (size_t i = 0; i < exps->length; i++)
+    {
+      Expression *expr = (*exps)[i];
+      tree t = build_expr (expr, const_p);
+      CONSTRUCTOR_APPEND_ELT (elms, size_int (i),
+			      convert_expr (t, expr->type, etype));
+    }
+
+  /* Create a new temporary to store the array.  */
+  tree var = build_local_temp (satype);
+
+  /* Fill any alignment holes with zeroes.  */
+  TypeStruct *ts = etype->baseElemOf ()->isTypeStruct ();
+  tree init = NULL;
+  if (ts && (!identity_compare_p (ts->sym) || ts->sym->isUnionDeclaration ()))
+    init = build_memset_call (var);
+
+  /* Initialize the temporary.  */
+  tree assign = modify_expr (var, build_constructor (satype, elms));
+  return compound_expr (compound_expr (init, assign), var);
+}
+
+
 /* Implicitly converts void* T to byte* as D allows { void[] a; &a[3]; }  */
 
 tree

gcc/d/d-tree.h

@@ -562,6 +562,7 @@ extern tree build_offset (tree, tree);
 extern tree build_memref (tree, tree, tree);
 extern tree build_array_set (tree, tree, tree);
 extern tree build_array_from_val (Type *, tree);
+extern tree build_array_from_exprs (Type *, Expressions *, bool);
 extern tree void_okay_p (tree);
 extern tree build_array_bounds_call (const Loc &);
 extern tree build_bounds_condition (const Loc &, tree, tree, bool);

gcc/d/expr.cc

@@ -2799,30 +2799,14 @@ public:
 
     /* Build an expression that assigns all expressions in KEYS
        to a constructor.  */
-    vec <constructor_elt, va_gc> *kelts = NULL;
-    vec_safe_reserve (kelts, e->keys->length);
-    for (size_t i = 0; i < e->keys->length; i++)
-      {
-	Expression *key = (*e->keys)[i];
-	tree t = build_expr (key);
-	CONSTRUCTOR_APPEND_ELT (kelts, size_int (i),
-				convert_expr (t, key->type, ta->index));
-      }
-    tree tkeys = make_array_type (ta->index, e->keys->length);
-    tree akeys = build_constructor (tkeys, kelts);
+    tree akeys = build_array_from_exprs (ta->index->sarrayOf (e->keys->length),
+					 e->keys, this->constp_);
+    tree init = stabilize_expr (&akeys);
 
     /* Do the same with all expressions in VALUES.  */
-    vec <constructor_elt, va_gc> *velts = NULL;
-    vec_safe_reserve (velts, e->values->length);
-    for (size_t i = 0; i < e->values->length; i++)
-      {
-	Expression *value = (*e->values)[i];
-	tree t = build_expr (value);
-	CONSTRUCTOR_APPEND_ELT (velts, size_int (i),
-				convert_expr (t, value->type, ta->next));
-      }
-    tree tvals = make_array_type (ta->next, e->values->length);
-    tree avals = build_constructor (tvals, velts);
+    tree avals = build_array_from_exprs (ta->next->sarrayOf (e->values->length),
+					 e->values, this->constp_);
+    init = compound_expr (init, stabilize_expr (&avals));
 
     /* Generate: _d_assocarrayliteralTX (ti, keys, vals);  */
     tree keys = d_array_value (build_ctype (ta->index->arrayOf ()),
@@ -2840,8 +2824,9 @@ public:
     vec <constructor_elt, va_gc> *ce = NULL;
     CONSTRUCTOR_APPEND_ELT (ce, TYPE_FIELDS (aatype), mem);
 
-    this->result_ = build_nop (build_ctype (e->type),
-			       build_constructor (aatype, ce));
+    tree result = build_nop (build_ctype (e->type),
+			     build_constructor (aatype, ce));
+    this->result_ = compound_expr (init, result);
   }
 
   /* Build a struct literal.  */

gcc/testsuite/gdc.dg/pr96152.d

@@ -0,0 +1,32 @@
+// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96152
+// { dg-additional-options "-fmain -funittest" }
+// { dg-do run { target hw } }
+// { dg-skip-if "needs gcc/config.d" { ! d_runtime } }
+auto assocArray(Keys, Values)(Keys keys, Values values)
+{
+    void* aa;
+    {
+        if (values.length > keys.length)
+            values = values[0 .. keys.length];
+        else if (keys.length > values.length)
+            keys = keys[0 .. values.length];
+        aa = aaLiteral(keys, values);
+    }
+    alias Key = typeof(keys[0]);
+    alias Value = typeof(values[0]);
+    return (() @trusted => cast(Value[Key]) aa)();
+}
+
+@safe unittest
+{
+    struct ThrowingElement
+    {
+        int i;
+        static bool b;
+        ~this(){
+            if (b)
+                throw new Exception("");
+        }
+    }
+    assert(assocArray([ThrowingElement()], [0]) == [ThrowingElement(): 0]);
+}