+/* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that
+ denotes the starting address of the memory access EXP.
+ Returns NULL_TREE if the offset is not constant or any component
+ is not BITS_PER_UNIT-aligned.
+ VALUEIZE if non-NULL is used to valueize SSA names. It should return
+ its argument or a constant if the argument is known to be constant. */
+
+tree
+get_addr_base_and_unit_offset_1 (tree exp, HOST_WIDE_INT *poffset,
+ tree (*valueize) (tree))
+{
+ HOST_WIDE_INT byte_offset = 0;
+
+ /* Compute cumulative byte-offset for nested component-refs and array-refs,
+ and find the ultimate containing object. */
+ while (1)
+ {
+ switch (TREE_CODE (exp))
+ {
+ case BIT_FIELD_REF:
+ {
+ HOST_WIDE_INT this_off = TREE_INT_CST_LOW (TREE_OPERAND (exp, 2));
+ if (this_off % BITS_PER_UNIT)
+ return NULL_TREE;
+ byte_offset += this_off / BITS_PER_UNIT;
+ }
+ break;
+
+ case COMPONENT_REF:
+ {
+ tree field = TREE_OPERAND (exp, 1);
+ tree this_offset = component_ref_field_offset (exp);
+ HOST_WIDE_INT hthis_offset;
+
+ if (!this_offset
+ || TREE_CODE (this_offset) != INTEGER_CST
+ || (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field))
+ % BITS_PER_UNIT))
+ return NULL_TREE;
+
+ hthis_offset = TREE_INT_CST_LOW (this_offset);
+ hthis_offset += (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field))
+ / BITS_PER_UNIT);
+ byte_offset += hthis_offset;
+ }
+ break;
+
+ case ARRAY_REF:
+ case ARRAY_RANGE_REF:
+ {
+ tree index = TREE_OPERAND (exp, 1);
+ tree low_bound, unit_size;
+
+ if (valueize
+ && TREE_CODE (index) == SSA_NAME)
+ index = (*valueize) (index);
+
+ /* If the resulting bit-offset is constant, track it. */
+ if (TREE_CODE (index) == INTEGER_CST
+ && (low_bound = array_ref_low_bound (exp),
+ TREE_CODE (low_bound) == INTEGER_CST)
+ && (unit_size = array_ref_element_size (exp),
+ TREE_CODE (unit_size) == INTEGER_CST))
+ {
+ offset_int woffset
+ = wi::sext (wi::to_offset (index) - wi::to_offset (low_bound),
+ TYPE_PRECISION (TREE_TYPE (index)));
+ woffset *= wi::to_offset (unit_size);
+ byte_offset += woffset.to_shwi ();
+ }
+ else
+ return NULL_TREE;
+ }
+ break;
+
+ case REALPART_EXPR:
+ break;
+
+ case IMAGPART_EXPR:
+ byte_offset += TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (exp)));
+ break;
+
+ case VIEW_CONVERT_EXPR:
+ break;
+
+ case MEM_REF:
+ {
+ tree base = TREE_OPERAND (exp, 0);
+ if (valueize
+ && TREE_CODE (base) == SSA_NAME)
+ base = (*valueize) (base);
+
+ /* Hand back the decl for MEM[&decl, off]. */
+ if (TREE_CODE (base) == ADDR_EXPR)
+ {
+ if (!integer_zerop (TREE_OPERAND (exp, 1)))
+ {
+ offset_int off = mem_ref_offset (exp);
+ byte_offset += off.to_short_addr ();
+ }
+ exp = TREE_OPERAND (base, 0);
+ }
+ goto done;
+ }
+
+ case TARGET_MEM_REF:
+ {
+ tree base = TREE_OPERAND (exp, 0);
+ if (valueize
+ && TREE_CODE (base) == SSA_NAME)
+ base = (*valueize) (base);
+
+ /* Hand back the decl for MEM[&decl, off]. */
+ if (TREE_CODE (base) == ADDR_EXPR)
+ {
+ if (TMR_INDEX (exp) || TMR_INDEX2 (exp))
+ return NULL_TREE;
+ if (!integer_zerop (TMR_OFFSET (exp)))
+ {
+ offset_int off = mem_ref_offset (exp);
+ byte_offset += off.to_short_addr ();
+ }
+ exp = TREE_OPERAND (base, 0);
+ }
+ goto done;
+ }
+
+ default:
+ goto done;
+ }
+
+ exp = TREE_OPERAND (exp, 0);
+ }
+done:
+
+ *poffset = byte_offset;
+ return exp;
+}
+
+/* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that
+ denotes the starting address of the memory access EXP.
+ Returns NULL_TREE if the offset is not constant or any component
+ is not BITS_PER_UNIT-aligned. */
+
+tree
+get_addr_base_and_unit_offset (tree exp, HOST_WIDE_INT *poffset)
+{
+ return get_addr_base_and_unit_offset_1 (exp, poffset, NULL);
+}
+