return lab;
}
+/* Subroutine for find_single_pointer_decl. */
+
+static tree
+find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
+ void *data)
+{
+ tree *pdecl = (tree *) data;
+
+ if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
+ {
+ if (*pdecl)
+ {
+ /* We already found a pointer decl; return anything other
+ than NULL_TREE to unwind from walk_tree signalling that
+ we have a duplicate. */
+ return *tp;
+ }
+ *pdecl = *tp;
+ }
+
+ return NULL_TREE;
+}
+
+/* Find the single DECL of pointer type in the tree T and return it.
+ If there are zero or more than one such DECLs, return NULL. */
+
+static tree
+find_single_pointer_decl (tree t)
+{
+ tree decl = NULL_TREE;
+
+ if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
+ {
+ /* find_single_pointer_decl_1 returns a non-zero value, causing
+ walk_tree to return a non-zero value, to indicate that it
+ found more than one pointer DECL. */
+ return NULL_TREE;
+ }
+
+ return decl;
+}
+
/* Create a new temporary name with PREFIX. Returns an identifier. */
static GTY(()) unsigned int tmp_var_id_num;
static inline tree
create_tmp_from_val (tree val)
{
- return create_tmp_var (TREE_TYPE (val), get_name (val));
+ return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val)), get_name (val));
}
/* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse
t = lookup_tmp_var (val, is_formal);
+ if (is_formal)
+ {
+ tree u = find_single_pointer_decl (val);
+
+ if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
+ u = DECL_GET_RESTRICT_BASE (u);
+ if (u && TYPE_RESTRICT (TREE_TYPE (u)))
+ {
+ if (DECL_BASED_ON_RESTRICT_P (t))
+ gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
+ else
+ {
+ DECL_BASED_ON_RESTRICT_P (t) = 1;
+ SET_DECL_RESTRICT_BASE (t, u);
+ }
+ }
+ }
+
if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
return GS_OK;
}
+/* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a
+ DECL_VALUE_EXPR, and it's worth re-examining things. */
+
+static enum gimplify_status
+gimplify_var_or_parm_decl (tree *expr_p)
+{
+ tree decl = *expr_p;
+
+ /* ??? If this is a local variable, and it has not been seen in any
+ outer BIND_EXPR, then it's probably the result of a duplicate
+ declaration, for which we've already issued an error. It would
+ be really nice if the front end wouldn't leak these at all.
+ Currently the only known culprit is C++ destructors, as seen
+ in g++.old-deja/g++.jason/binding.C. */
+ if (TREE_CODE (decl) == VAR_DECL
+ && !DECL_SEEN_IN_BIND_EXPR_P (decl)
+ && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
+ && decl_function_context (decl) == current_function_decl)
+ {
+ gcc_assert (errorcount || sorrycount);
+ return GS_ERROR;
+ }
+
+ /* If the decl is an alias for another expression, substitute it now. */
+ if (DECL_HAS_VALUE_EXPR_P (decl))
+ {
+ *expr_p = unshare_expr (DECL_VALUE_EXPR (decl));
+ return GS_OK;
+ }
+
+ return GS_ALL_DONE;
+}
+
+
/* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR
node pointed to by EXPR_P.
/* We can handle anything that get_inner_reference can deal with. */
for (p = expr_p; ; p = &TREE_OPERAND (*p, 0))
{
+ restart:
/* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */
if (TREE_CODE (*p) == INDIRECT_REF)
*p = fold_indirect_ref (*p);
- if (!handled_component_p (*p))
+
+ if (handled_component_p (*p))
+ ;
+ /* Expand DECL_VALUE_EXPR now. In some cases that may expose
+ additional COMPONENT_REFs. */
+ else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL)
+ && gimplify_var_or_parm_decl (p) == GS_OK)
+ goto restart;
+ else
break;
+
VEC_safe_push (tree, heap, stack, *p);
}
}
}
- /* Step 2 is to gimplify the base expression. */
- tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback);
+ /* Step 2 is to gimplify the base expression. Make sure lvalue is set
+ so as to match the min_lval predicate. Failure to do so may result
+ in the creation of large aggregate temporaries. */
+ tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval,
+ fallback | fb_lvalue);
ret = MIN (ret, tret);
/* And finally, the indices and operands to BIT_FIELD_REF. During this
so we don't have to figure out what's missing ourselves. */
gcc_assert (purpose);
- if (zero_sized_field_decl (purpose))
+ /* Skip zero-sized fields, unless value has side-effects. This can
+ happen with calls to functions returning a zero-sized type, which
+ we shouldn't discard. As a number of downstream passes don't
+ expect sets of zero-sized fields, we rely on the gimplification of
+ the MODIFY_EXPR we make below to drop the assignment statement. */
+ if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose))
continue;
/* If we have a RANGE_EXPR, we have to build a loop to assign the
{
tree type_domain;
tree min_val = size_zero_node;
+ tree osub = sub;
sub = fold_indirect_ref_rhs (sub);
if (! sub)
- sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), sub);
+ sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub);
type_domain = TYPE_DOMAIN (TREE_TYPE (sub));
if (type_domain && TYPE_MIN_VALUE (type_domain))
min_val = TYPE_MIN_VALUE (type_domain);
{
unsigned HOST_WIDE_INT ix;
constructor_elt *ce;
+ tree temp = NULL_TREE;
for (ix = 0;
VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (*expr_p),
ix, ce);
ix++)
if (TREE_SIDE_EFFECTS (ce->value))
- gimplify_expr (&ce->value, pre_p, post_p,
- gimple_test_f, fallback);
+ append_to_statement_list (ce->value, &temp);
- *expr_p = NULL_TREE;
+ *expr_p = temp;
+ ret = GS_OK;
}
-
- ret = GS_ALL_DONE;
+ /* C99 code may assign to an array in a constructed
+ structure or union, and this has undefined behavior only
+ on execution, so create a temporary if an lvalue is
+ required. */
+ else if (fallback == fb_lvalue)
+ {
+ *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p);
+ lang_hooks.mark_addressable (*expr_p);
+ }
+ else
+ ret = GS_ALL_DONE;
break;
/* The following are special cases that are not handled by the
break;
case VAR_DECL:
- /* ??? If this is a local variable, and it has not been seen in any
- outer BIND_EXPR, then it's probably the result of a duplicate
- declaration, for which we've already issued an error. It would
- be really nice if the front end wouldn't leak these at all.
- Currently the only known culprit is C++ destructors, as seen
- in g++.old-deja/g++.jason/binding.C. */
- tmp = *expr_p;
- if (!TREE_STATIC (tmp) && !DECL_EXTERNAL (tmp)
- && decl_function_context (tmp) == current_function_decl
- && !DECL_SEEN_IN_BIND_EXPR_P (tmp))
- {
- gcc_assert (errorcount || sorrycount);
- ret = GS_ERROR;
- break;
- }
- /* FALLTHRU */
-
case PARM_DECL:
- tmp = *expr_p;
-
- /* If this is a local variable sized decl, it must be accessed
- indirectly. Perform that substitution. */
- if (DECL_HAS_VALUE_EXPR_P (tmp))
- {
- *expr_p = unshare_expr (DECL_VALUE_EXPR (tmp));
- ret = GS_OK;
- break;
- }
-
- ret = GS_ALL_DONE;
+ ret = gimplify_var_or_parm_decl (expr_p);
break;
case SSA_NAME:
/* Historically, the compiler has treated a bare
reference to a volatile lvalue as forcing a load. */
tree type = TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p));
- tree tmp = create_tmp_var (type, "vol");
+ /* Normally, we do want to create a temporary for a
+ TREE_ADDRESSABLE type because such a type should not be
+ copied by bitwise-assignment. However, we make an
+ exception here, as all we are doing here is ensuring that
+ we read the bytes that make up the type. We use
+ create_tmp_var_raw because create_tmp_var will abort when
+ given a TREE_ADDRESSABLE type. */
+ tree tmp = create_tmp_var_raw (type, "vol");
+ gimple_add_tmp_var (tmp);
*expr_p = build (MODIFY_EXPR, type, tmp, *expr_p);
}
else
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