--- /dev/null
+/* PR tree-optimization/50569 */
+/* Reported by Paul Koning <pkoning@gcc.gnu.org> */
+/* Reduced testcase by Mikael Pettersson <mikpe@it.uu.se> */
+
+struct event {
+ struct {
+ unsigned int sec;
+ } sent __attribute__((packed));
+};
+
+void __attribute__((noinline,noclone)) frob_entry(char *buf)
+{
+ struct event event;
+
+ __builtin_memcpy(&event, buf, sizeof(event));
+ if (event.sent.sec < 64) {
+ event.sent.sec = -1U;
+ __builtin_memcpy(buf, &event, sizeof(event));
+ }
+}
+
+int main(void)
+{
+ union {
+ char buf[1 + sizeof(struct event)];
+ int align;
+ } u;
+
+ __builtin_memset(&u, 0, sizeof u);
+
+ frob_entry(&u.buf[1]);
+
+ return 0;
+}
return fold_build2_loc (loc, MEM_REF, exp_type, base, off);
}
+DEF_VEC_ALLOC_P_STACK (tree);
+#define VEC_tree_stack_alloc(alloc) VEC_stack_alloc (tree, alloc)
+
/* Construct a memory reference to a part of an aggregate BASE at the given
- OFFSET and of the same type as MODEL. In case this is a reference to a
- component, the function will replicate the last COMPONENT_REF of model's
- expr to access it. GSI and INSERT_AFTER have the same meaning as in
- build_ref_for_offset. */
+ OFFSET and of the type of MODEL. In case this is a chain of references
+ to component, the function will replicate the chain of COMPONENT_REFs of
+ the expression of MODEL to access it. GSI and INSERT_AFTER have the same
+ meaning as in build_ref_for_offset. */
static tree
build_ref_for_model (location_t loc, tree base, HOST_WIDE_INT offset,
struct access *model, gimple_stmt_iterator *gsi,
bool insert_after)
{
+ tree type = model->type, t;
+ VEC(tree,stack) *cr_stack = NULL;
+
if (TREE_CODE (model->expr) == COMPONENT_REF)
{
- tree t, exp_type, fld = TREE_OPERAND (model->expr, 1);
- offset -= int_bit_position (fld);
- exp_type = TREE_TYPE (TREE_OPERAND (model->expr, 0));
- t = build_ref_for_offset (loc, base, offset, exp_type, gsi, insert_after);
- return fold_build3_loc (loc, COMPONENT_REF, TREE_TYPE (fld), t, fld,
- NULL_TREE);
+ tree expr = model->expr;
+
+ /* Create a stack of the COMPONENT_REFs so later we can walk them in
+ order from inner to outer. */
+ cr_stack = VEC_alloc (tree, stack, 6);
+
+ do {
+ tree field = TREE_OPERAND (expr, 1);
+ offset -= int_bit_position (field);
+
+ VEC_safe_push (tree, stack, cr_stack, expr);
+
+ expr = TREE_OPERAND (expr, 0);
+ type = TREE_TYPE (expr);
+ } while (TREE_CODE (expr) == COMPONENT_REF);
}
- else
- return build_ref_for_offset (loc, base, offset, model->type,
- gsi, insert_after);
+
+ t = build_ref_for_offset (loc, base, offset, type, gsi, insert_after);
+
+ if (TREE_CODE (model->expr) == COMPONENT_REF)
+ {
+ unsigned i;
+ tree expr;
+
+ /* Now replicate the chain of COMPONENT_REFs from inner to outer. */
+ FOR_EACH_VEC_ELT_REVERSE (tree, cr_stack, i, expr)
+ {
+ tree field = TREE_OPERAND (expr, 1);
+ t = fold_build3_loc (loc, COMPONENT_REF, TREE_TYPE (field), t, field,
+ NULL_TREE);
+ }
+
+ VEC_free (tree, stack, cr_stack);
+ }
+
+ return t;
}
/* Construct a memory reference consisting of component_refs and array_refs to