return tree_to_shwi (size);
}
+
+/* Calculate CRC for the initial CRC and given POLYNOMIAL.
+ CRC_BITS is CRC size. */
+
+static unsigned HOST_WIDE_INT
+calculate_crc (unsigned HOST_WIDE_INT crc,
+ unsigned HOST_WIDE_INT polynomial,
+ unsigned short crc_bits)
+{
+ unsigned HOST_WIDE_INT msb = HOST_WIDE_INT_1U << (crc_bits - 1);
+ crc = crc << (crc_bits - 8);
+ for (short i = 8; i > 0; --i)
+ {
+ if (crc & msb)
+ crc = (crc << 1) ^ polynomial;
+ else
+ crc <<= 1;
+ }
+ /* Zero out bits in crc beyond the specified number of crc_bits. */
+ if (crc_bits < sizeof (crc) * CHAR_BIT)
+ crc &= (HOST_WIDE_INT_1U << crc_bits) - 1;
+ return crc;
+}
+
+/* Assemble CRC table with 256 elements for the given POLYNOM and CRC_BITS with
+ given ID.
+ ID is the identifier of the table, the name of the table is unique,
+ contains CRC size and the polynomial.
+ POLYNOM is the polynomial used to calculate the CRC table's elements.
+ CRC_BITS is the size of CRC, may be 8, 16, ... . */
+
+rtx
+assemble_crc_table (tree id, unsigned HOST_WIDE_INT polynom,
+ unsigned short crc_bits)
+{
+ unsigned table_el_n = 0x100;
+ tree ar = build_array_type (make_unsigned_type (crc_bits),
+ build_index_type (size_int (table_el_n - 1)));
+ tree decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, id, ar);
+ SET_DECL_ASSEMBLER_NAME (decl, id);
+ DECL_ARTIFICIAL (decl) = 1;
+ rtx tab = gen_rtx_SYMBOL_REF (Pmode, IDENTIFIER_POINTER (id));
+ TREE_ASM_WRITTEN (decl) = 0;
+
+ /* Initialize the table. */
+ vec<tree, va_gc> *initial_values;
+ vec_alloc (initial_values, table_el_n);
+ for (size_t i = 0; i < table_el_n; ++i)
+ {
+ unsigned HOST_WIDE_INT crc = calculate_crc (i, polynom, crc_bits);
+ tree element = build_int_cstu (make_unsigned_type (crc_bits), crc);
+ vec_safe_push (initial_values, element);
+ }
+ DECL_INITIAL (decl) = build_constructor_from_vec (ar, initial_values);
+
+ TREE_READONLY (decl) = 1;
+ TREE_STATIC (decl) = 1;
+
+ if (TREE_PUBLIC (id))
+ {
+ TREE_PUBLIC (decl) = 1;
+ make_decl_one_only (decl, DECL_ASSEMBLER_NAME (decl));
+ }
+
+ mark_decl_referenced (decl);
+ varpool_node::finalize_decl (decl);
+
+ return tab;
+}
+
+/* Generate CRC lookup table by calculating CRC for all possible
+ 8-bit data values. The table is stored with a specific name in the read-only
+ static data section.
+ POLYNOM is the polynomial used to calculate the CRC table's elements.
+ CRC_BITS is the size of CRC, may be 8, 16, ... . */
+
+rtx
+generate_crc_table (unsigned HOST_WIDE_INT polynom, unsigned short crc_bits)
+{
+ gcc_assert (crc_bits <= 64);
+
+ /* Buf size - 24 letters + 6 '_'
+ + 20 numbers (2 for crc bit size + 2 for 0x + 16 for 64-bit polynomial)
+ + 1 for \0. */
+ char buf[51];
+ sprintf (buf, "crc_table_for_crc_%u_polynomial_" HOST_WIDE_INT_PRINT_HEX,
+ crc_bits, polynom);
+
+ tree id = maybe_get_identifier (buf);
+ if (id)
+ return gen_rtx_SYMBOL_REF (Pmode, IDENTIFIER_POINTER (id));
+
+ id = get_identifier (buf);
+ return assemble_crc_table (id, polynom, crc_bits);
+}
+
+/* Generate table-based CRC code for the given CRC, INPUT_DATA and the
+ POLYNOMIAL (without leading 1).
+
+ First, using POLYNOMIAL's value generates CRC table of 256 elements,
+ then generates the assembly for the following code,
+ where crc_bit_size and data_bit_size may be 8, 16, 32, 64, depending on CRC:
+
+ for (int i = 0; i < data_bit_size / 8; i++)
+ crc = (crc << 8) ^ crc_table[(crc >> (crc_bit_size - 8))
+ ^ (data >> (data_bit_size - (i + 1) * 8)
+ & 0xFF))];
+
+ So to take values from the table, we need 8-bit data.
+ If input data size is not 8, then first we extract upper 8 bits,
+ then the other 8 bits, and so on. */
+
+void
+calculate_table_based_CRC (rtx *crc, const rtx &input_data,
+ const rtx &polynomial,
+ machine_mode crc_mode, machine_mode data_mode)
+{
+ unsigned short crc_bit_size = GET_MODE_BITSIZE (crc_mode).to_constant ();
+ unsigned short data_size = GET_MODE_SIZE (data_mode).to_constant ();
+ machine_mode mode = GET_MODE (*crc);
+ rtx tab = generate_crc_table (UINTVAL (polynomial), crc_bit_size);
+
+ for (unsigned short i = 0; i < data_size; i++)
+ {
+ /* crc >> (crc_bit_size - 8). */
+ *crc = force_reg (crc_mode, *crc);
+ rtx op1 = expand_shift (RSHIFT_EXPR, mode, *crc, crc_bit_size - 8,
+ NULL_RTX, 1);
+
+ /* data >> (8 * (GET_MODE_SIZE (data_mode).to_constant () - i - 1)). */
+ unsigned range_8 = 8 * (data_size - i - 1);
+ rtx data = force_reg (data_mode, input_data);
+ data = expand_shift (RSHIFT_EXPR, mode, data, range_8, NULL_RTX, 1);
+
+ /* data >> (8 * (GET_MODE_SIZE (data_mode)
+ .to_constant () - i - 1)) & 0xFF. */
+ rtx data_final = expand_and (mode, data,
+ gen_int_mode (255, data_mode), NULL_RTX);
+
+ /* (crc >> (crc_bit_size - 8)) ^ data_8bit. */
+ rtx in = expand_binop (mode, xor_optab, op1, data_final,
+ NULL_RTX, 1, OPTAB_WIDEN);
+
+ /* ((crc >> (crc_bit_size - 8)) ^ data_8bit) & 0xFF. */
+ rtx index = expand_and (mode, in, gen_int_mode (255, mode),
+ NULL_RTX);
+ int log_crc_size = exact_log2 (GET_MODE_SIZE (crc_mode).to_constant ());
+ index = expand_shift (LSHIFT_EXPR, mode, index,
+ log_crc_size, NULL_RTX, 0);
+
+ rtx addr = gen_reg_rtx (Pmode);
+ convert_move (addr, index, 1);
+ addr = expand_binop (Pmode, add_optab, addr, tab, NULL_RTX,
+ 0, OPTAB_DIRECT);
+
+ /* crc_table[(crc >> (crc_bit_size - 8)) ^ data_8bit] */
+ rtx tab_el = validize_mem (gen_rtx_MEM (crc_mode, addr));
+
+ /* (crc << 8) if CRC is larger than 8, otherwise crc = 0. */
+ rtx high = NULL_RTX;
+ if (crc_bit_size != 8)
+ high = expand_shift (LSHIFT_EXPR, mode, *crc, 8, NULL_RTX, 0);
+ else
+ high = gen_int_mode (0, mode);
+
+ /* crc = (crc << 8)
+ ^ crc_table[(crc >> (crc_bit_size - 8)) ^ data_8bit]; */
+ *crc = expand_binop (mode, xor_optab, tab_el, high, NULL_RTX, 1,
+ OPTAB_WIDEN);
+ }
+}
+
+/* Generate table-based CRC code for the given CRC, INPUT_DATA and the
+ POLYNOMIAL (without leading 1).
+
+ CRC is OP1, data is OP2 and the polynomial is OP3.
+ This must generate a CRC table and an assembly for the following code,
+ where crc_bit_size and data_bit_size may be 8, 16, 32, 64:
+ uint_crc_bit_size_t
+ crc_crc_bit_size (uint_crc_bit_size_t crc_init,
+ uint_data_bit_size_t data, size_t size)
+ {
+ uint_crc_bit_size_t crc = crc_init;
+ for (int i = 0; i < data_bit_size / 8; i++)
+ crc = (crc << 8) ^ crc_table[(crc >> (crc_bit_size - 8))
+ ^ (data >> (data_bit_size - (i + 1) * 8)
+ & 0xFF))];
+ return crc;
+ } */
+
+void
+expand_crc_table_based (rtx op0, rtx op1, rtx op2, rtx op3,
+ machine_mode data_mode)
+{
+ gcc_assert (!CONST_INT_P (op0));
+ gcc_assert (CONST_INT_P (op3));
+ machine_mode crc_mode = GET_MODE (op0);
+ rtx crc = gen_reg_rtx (crc_mode);
+ convert_move (crc, op1, 0);
+ calculate_table_based_CRC (&crc, op2, op3, crc_mode, data_mode);
+ convert_move (op0, crc, 0);
+}
+
+/* Generate the common operation for reflecting values:
+ *OP = (*OP & AND1_VALUE) << SHIFT_VAL | (*OP & AND2_VALUE) >> SHIFT_VAL; */
+
+void
+gen_common_operation_to_reflect (rtx *op,
+ unsigned HOST_WIDE_INT and1_value,
+ unsigned HOST_WIDE_INT and2_value,
+ unsigned shift_val)
+{
+ rtx op1 = expand_and (GET_MODE (*op), *op,
+ gen_int_mode (and1_value, GET_MODE (*op)), NULL_RTX);
+ op1 = expand_shift (LSHIFT_EXPR, GET_MODE (*op), op1, shift_val, op1, 0);
+ rtx op2 = expand_and (GET_MODE (*op), *op,
+ gen_int_mode (and2_value, GET_MODE (*op)), NULL_RTX);
+ op2 = expand_shift (RSHIFT_EXPR, GET_MODE (*op), op2, shift_val, op2, 1);
+ *op = expand_binop (GET_MODE (*op), ior_optab, op1,
+ op2, *op, 0, OPTAB_LIB_WIDEN);
+}
+
+/* Reflect 64-bit value for the 64-bit target. */
+
+void
+reflect_64_bit_value (rtx *op)
+{
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x00000000FFFFFFFF),
+ HOST_WIDE_INT_C (0xFFFFFFFF00000000), 32);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0000FFFF0000FFFF),
+ HOST_WIDE_INT_C (0xFFFF0000FFFF0000), 16);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x00FF00FF00FF00FF),
+ HOST_WIDE_INT_C (0xFF00FF00FF00FF00), 8);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0F0F0F0F0F0F0F0F),
+ HOST_WIDE_INT_C (0xF0F0F0F0F0F0F0F0), 4);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x3333333333333333),
+ HOST_WIDE_INT_C (0xCCCCCCCCCCCCCCCC), 2);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x5555555555555555),
+ HOST_WIDE_INT_C (0xAAAAAAAAAAAAAAAA), 1);
+}
+
+/* Reflect 32-bit value for the 32-bit target. */
+
+void
+reflect_32_bit_value (rtx *op)
+{
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0000FFFF),
+ HOST_WIDE_INT_C (0xFFFF0000), 16);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x00FF00FF),
+ HOST_WIDE_INT_C (0xFF00FF00), 8);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0F0F0F0F),
+ HOST_WIDE_INT_C (0xF0F0F0F0), 4);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x33333333),
+ HOST_WIDE_INT_C (0xCCCCCCCC), 2);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x55555555),
+ HOST_WIDE_INT_C (0xAAAAAAAA), 1);
+}
+
+/* Reflect 16-bit value for the 16-bit target. */
+
+void
+reflect_16_bit_value (rtx *op)
+{
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x00FF),
+ HOST_WIDE_INT_C (0xFF00), 8);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0F0F),
+ HOST_WIDE_INT_C (0xF0F0), 4);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x3333),
+ HOST_WIDE_INT_C (0xCCCC), 2);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x5555),
+ HOST_WIDE_INT_C (0xAAAA), 1);
+}
+
+/* Reflect 8-bit value for the 8-bit target. */
+
+void
+reflect_8_bit_value (rtx *op)
+{
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x0F),
+ HOST_WIDE_INT_C (0xF0), 4);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x33),
+ HOST_WIDE_INT_C (0xCC), 2);
+ gen_common_operation_to_reflect (op, HOST_WIDE_INT_C (0x55),
+ HOST_WIDE_INT_C (0xAA), 1);
+}
+
+/* Generate instruction sequence which reflects the value of the OP
+ using shift, and, or operations. OP's mode may be less than word_mode. */
+
+void
+generate_reflecting_code_standard (rtx *op)
+{
+ gcc_assert (GET_MODE_BITSIZE (GET_MODE (*op)).to_constant () >= 8
+ && GET_MODE_BITSIZE (GET_MODE (*op)).to_constant () <= 64);
+
+ if (GET_MODE_BITSIZE (GET_MODE (*op)).to_constant () == 64)
+ reflect_64_bit_value (op);
+ else if (GET_MODE_BITSIZE (GET_MODE (*op)).to_constant () == 32)
+ reflect_32_bit_value (op);
+ else if (GET_MODE_BITSIZE (GET_MODE (*op)).to_constant () == 16)
+ reflect_16_bit_value (op);
+ else
+ reflect_8_bit_value (op);
+}
+
+/* Generate table-based reversed CRC code for the given CRC, INPUT_DATA and
+ the POLYNOMIAL (without leading 1).
+
+ CRC is OP1, data is OP2 and the polynomial is OP3.
+ This must generate CRC table and assembly for the following code,
+ where crc_bit_size and data_bit_size may be 8, 16, 32, 64:
+ uint_crc_bit_size_t
+ crc_crc_bit_size (uint_crc_bit_size_t crc_init,
+ uint_data_bit_size_t data, size_t size)
+ {
+ reflect (crc_init)
+ uint_crc_bit_size_t crc = crc_init;
+ reflect (data);
+ for (int i = 0; i < data_bit_size / 8; i++)
+ crc = (crc << 8) ^ crc_table[(crc >> (crc_bit_size - 8))
+ ^ (data >> (data_bit_size - (i + 1) * 8) & 0xFF))];
+ reflect (crc);
+ return crc;
+ } */
+
+void
+expand_reversed_crc_table_based (rtx op0, rtx op1, rtx op2, rtx op3,
+ machine_mode data_mode,
+ void (*gen_reflecting_code) (rtx *op))
+{
+ gcc_assert (!CONST_INT_P (op0));
+ gcc_assert (CONST_INT_P (op3));
+ machine_mode crc_mode = GET_MODE (op0);
+
+ rtx crc = gen_reg_rtx (crc_mode);
+ convert_move (crc, op1, 0);
+ gen_reflecting_code (&crc);
+
+ rtx data = gen_reg_rtx (data_mode);
+ convert_move (data, op2, 0);
+ gen_reflecting_code (&data);
+
+ calculate_table_based_CRC (&crc, data, op3, crc_mode, data_mode);
+
+ gen_reflecting_code (&crc);
+ convert_move (op0, crc, 0);
+}
#define mask_fold_left_direct { 1, 1, false }
#define mask_len_fold_left_direct { 1, 1, false }
#define check_ptrs_direct { 0, 0, false }
+#define crc_direct { 1, -1, true }
const direct_internal_fn_info direct_internal_fn_array[IFN_LAST + 1] = {
#define DEF_INTERNAL_FN(CODE, FLAGS, FNSPEC) not_direct,
expand_fn_using_insn (stmt, icode, 1, nargs);
}
+/* Expand CRC call STMT. */
+
+static void
+expand_crc_optab_fn (internal_fn fn, gcall *stmt, convert_optab optab)
+{
+ tree lhs = gimple_call_lhs (stmt);
+ tree rhs1 = gimple_call_arg (stmt, 0); // crc
+ tree rhs2 = gimple_call_arg (stmt, 1); // data
+ tree rhs3 = gimple_call_arg (stmt, 2); // polynomial
+
+ tree result_type = TREE_TYPE (lhs);
+ tree data_type = TREE_TYPE (rhs2);
+
+ gcc_assert (TYPE_MODE (result_type) >= TYPE_MODE (data_type));
+
+ rtx dest = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
+ rtx crc = expand_normal (rhs1);
+ rtx data = expand_normal (rhs2);
+ gcc_assert (TREE_CODE (rhs3) == INTEGER_CST);
+ rtx polynomial = gen_rtx_CONST_INT (TYPE_MODE (result_type),
+ TREE_INT_CST_LOW (rhs3));
+
+ /* Use target specific expansion if it exists.
+ Otherwise, generate table-based CRC. */
+ if (direct_internal_fn_supported_p (fn, tree_pair (data_type, result_type),
+ OPTIMIZE_FOR_SPEED))
+ {
+ class expand_operand ops[4];
+ create_call_lhs_operand (&ops[0], dest, TYPE_MODE (result_type));
+ create_input_operand (&ops[1], crc, TYPE_MODE (result_type));
+ create_input_operand (&ops[2], data, TYPE_MODE (data_type));
+ create_input_operand (&ops[3], polynomial, TYPE_MODE (result_type));
+ insn_code icode = convert_optab_handler (optab, TYPE_MODE (data_type),
+ TYPE_MODE (result_type));
+ expand_insn (icode, 4, ops);
+ assign_call_lhs (lhs, dest, &ops[0]);
+ }
+ else
+ {
+ /* We're bypassing all the operand conversions that are done in the
+ case when we get an icode, operands and pass that off to expand_insn.
+
+ That path has special case handling for promoted return values which
+ we must emulate here (is the same kind of special treatment ever
+ needed for input arguments here?).
+
+ In particular we do not want to store directly into a promoted
+ SUBREG destination, instead store into a suitably sized pseudo. */
+ rtx orig_dest = dest;
+ if (SUBREG_P (dest) && SUBREG_PROMOTED_VAR_P (dest))
+ dest = gen_reg_rtx (GET_MODE (dest));
+
+ /* If it's IFN_CRC generate bit-forward CRC. */
+ if (fn == IFN_CRC)
+ expand_crc_table_based (dest, crc, data, polynomial,
+ TYPE_MODE (data_type));
+ else
+ /* If it's IFN_CRC_REV generate bit-reversed CRC. */
+ expand_reversed_crc_table_based (dest, crc, data, polynomial,
+ TYPE_MODE (data_type),
+ generate_reflecting_code_standard);
+
+ /* Now get the return value where it needs to be, taking care to
+ ensure it's promoted appropriately if the ABI demands it.
+
+ Re-use assign_call_lhs to handle the details. */
+ class expand_operand ops[4];
+ create_call_lhs_operand (&ops[0], dest, TYPE_MODE (result_type));
+ ops[0].value = dest;
+ assign_call_lhs (lhs, orig_dest, &ops[0]);
+ }
+}
+
/* Expanders for optabs that can use expand_direct_optab_fn. */
#define expand_unary_optab_fn(FN, STMT, OPTAB) \
#define direct_cond_len_unary_optab_supported_p direct_optab_supported_p
#define direct_cond_len_binary_optab_supported_p direct_optab_supported_p
#define direct_cond_len_ternary_optab_supported_p direct_optab_supported_p
+#define direct_crc_optab_supported_p convert_optab_supported_p
#define direct_mask_load_optab_supported_p convert_optab_supported_p
#define direct_load_lanes_optab_supported_p multi_vector_optab_supported_p
#define direct_mask_load_lanes_optab_supported_p multi_vector_optab_supported_p
projects / thirdparty / gcc.git / commitdiff
