(* * Copyright Data61, CSIRO (ABN 41 687 119 230) * * SPDX-License-Identifier: BSD-2-Clause *) theory Examples imports Bit_Shifts_Infix_Syntax Next_and_Prev Signed_Division_Word Bitwise begin context includes bit_operations_syntax begin section \\<^typ>\nat\\ lemma \bit (1705 :: nat) (Suc (Suc (Suc 0)))\ by simp lemma \bit (1705 :: nat) 3\ by simp lemma \\ bit (1 :: nat) (Suc (Suc (Suc 0)))\ by simp lemma \\ bit (1 :: nat) 3\ by simp lemma \(1705 :: nat) AND 42 = 40\ by simp lemma \(1705 :: nat) AND Suc 0 = 1\ by simp lemma \(1705 :: nat) OR 42 = 1707\ by simp lemma \(1705 :: nat) OR Suc 0 = 1705\ by simp lemma \(1705 :: nat) XOR 42 = 1667\ by simp lemma \(1705 :: nat) XOR 1 = 1704\ by simp lemma \push_bit 3 (1705 :: nat) = 13640\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 13640\ by simp lemma \push_bit 3 (Suc 0) = 8\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (Suc 0) = 8\ by simp lemma \(1705 :: nat) << 3 = 13640\ by simp lemma \(1705 :: nat) << Suc (Suc (Suc 0)) = 13640\ by simp lemma \Suc 0 << 3 = 8\ by simp lemma \Suc 0 << Suc (Suc (Suc 0)) = 8\ by simp lemma \drop_bit 3 (1705 :: nat) = 213\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 213\ by simp lemma \drop_bit 3 (Suc 0) = 0\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (Suc 0) = 0\ by simp lemma \(1705 :: nat) >> 3 = 213\ by simp lemma \(1705 :: nat) >> Suc (Suc (Suc 0)) = 213\ by simp lemma \Suc 0 >> 3 = 0\ by simp lemma \Suc 0 >> Suc (Suc (Suc 0)) = 0\ by simp lemma \take_bit 3 (1705 :: nat) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (1705 :: nat) = 1\ by (simp flip: add_2_eq_Suc) lemma \take_bit 3 (Suc 0) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (Suc 0) = 1\ by simp section \\<^typ>\int\\ lemma \bit (1705 :: int) (Suc (Suc (Suc 0)))\ by simp lemma \bit (1705 :: int) 3\ by simp lemma \\ bit (- 1705 :: int) (Suc (Suc (Suc 0)))\ by simp lemma \\ bit (- 1705 :: int) 3\ by simp lemma \\ bit (1 :: int) (Suc (Suc (Suc 0)))\ by simp lemma \\ bit (1 :: int) 3\ by simp lemma \(NOT 1705 :: int) = - 1706\ by simp lemma \(NOT (- 42 :: int)) = 41\ by simp lemma \(NOT 1 :: int) = - 2\ by simp lemma \(1705 :: int) AND 42 = 40\ by simp lemma \(1705 :: int) AND - 42 = 1664\ by simp lemma \(1705 :: int) AND 1 = 1\ by simp lemma \- (1705 :: int) AND 42 = 2\ by simp lemma \- (1705 :: int) AND - 42 = - 1706\ by simp lemma \- (1705 :: int) AND 1 = 1\ by simp lemma \(1705 :: int) OR 42 = 1707\ by simp lemma \(1705 :: int) OR - 42 = - 1\ by simp lemma \(1705 :: int) OR 1 = 1705\ by simp lemma \- (1705 :: int) OR 42 = - 1665\ by simp lemma \- (1705 :: int) OR - 42 = - 41\ by simp lemma \- (1705 :: int) OR 1 = - 1705\ by simp lemma \(1705 :: int) XOR 42 = 1667\ by simp lemma \(1705 :: int) XOR - 42 = - 1665\ by simp lemma \(1705 :: int) XOR 1 = 1704\ by simp lemma \- (1705 :: int) XOR 42 = - 1667\ by simp lemma \- (1705 :: int) XOR - 42 = 1665\ by simp lemma \- (1705 :: int) XOR 1 = - 1706\ by simp lemma \push_bit 3 (1705 :: int) = 13640\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (1705 :: int) = 13640\ by simp lemma \push_bit 3 (- 1705 :: int) = - 13640\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = - 13640\ by simp lemma \push_bit 3 (1 :: int) = 8\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (1 :: int) = 8\ by simp lemma \push_bit 3 (- 1 :: int) = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \push_bit (Suc (Suc (Suc 0))) (- 1 :: int) = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \(1705 :: int) << 3 = 13640\ by simp lemma \(1705 :: int) << Suc (Suc (Suc 0)) = 13640\ by simp lemma \(- 1705 :: int) << 3 = - 13640\ by simp lemma \(- 1705 :: int) << Suc (Suc (Suc 0)) = - 13640\ by simp lemma \(1 :: int) << 3 = 8\ by simp lemma \(1 :: int) << Suc (Suc (Suc 0)) = 8\ by simp lemma \(- 1 :: int) << 3 = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \(- 1 :: int) << Suc (Suc (Suc 0)) = - 8\ by simp lemma \drop_bit 3 (1705 :: int) = 213\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (1705 :: int) = 213\ by simp lemma \drop_bit 3 (- 1705 :: int) = - 214\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = - 214\ by simp lemma \drop_bit 3 (1 :: int) = 0\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (1 :: int) = 0\ by simp lemma \(1705 :: int) >> 3 = 213\ by simp lemma \(1705 :: int) >> Suc (Suc (Suc 0)) = 213\ by simp lemma \(- 1705 :: int) >> 3 = - 214\ by simp lemma \(- 1705 :: int) >> Suc (Suc (Suc 0)) = - 214\ by simp lemma \(1 :: int) >> 3 = 0\ by simp lemma \(1 :: int) >> Suc (Suc (Suc 0)) = 0\ by simp lemma \take_bit 3 (1705 :: int) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (1705 :: int) = 1\ by (simp flip: add_2_eq_Suc) lemma \take_bit 3 (- 1705 :: int) = 7\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = 7\ by (simp flip: add_2_eq_Suc) lemma \take_bit 3 (1 :: int) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (1 :: int) = 1\ by simp lemma \take_bit 3 (- 1 :: int) = 7\ by (simp add: mask_eq_exp_minus_1) lemma \take_bit (Suc (Suc (Suc 0))) (- 1 :: int) = 7\ by (simp add: mask_eq_exp_minus_1) lemma \signed_take_bit 3 (1705 :: int) = - 7\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (1705 :: int) = - 7\ by simp lemma \signed_take_bit 3 (- 1705 :: int) = 7\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (- 1705 :: int) = 7\ by simp lemma \signed_take_bit 3 (1 :: int) = 1\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (1 :: int) = 1\ by simp section \\<^typ>\'a word\\ lemma \(1705 :: 8 word) = 169\ by simp lemma \(- 1705 :: 8 word) = 87\ by simp lemma \(257 :: 8 word) = 1\ by simp lemma \(42 :: 8 word) \ 1705\ by simp lemma \(- 42 :: 8 word) \ 230\ by simp lemma \(42 :: 8 word) \ - 1705\ by simp lemma \- (42 :: 8 word) \ 235\ by simp lemma \(1 :: 8 word) \ 1705\ by simp lemma \(- 1 :: 8 word) \ 65535\ by simp lemma \(42 :: 8 word) < 1705\ by simp lemma \(- 42 :: 8 word) < 230\ by simp lemma \(42 :: 8 word) < - 1705\ by simp lemma \- (42 :: 8 word) < 230\ by simp lemma \(1 :: 8 word) < 1705\ by simp lemma \(1705 :: 8 word) < - 1\ by simp lemma \(42 :: 8 word) \s 1333\ by simp lemma \(- 42 :: 8 word) \s 230\ by simp lemma \(42 :: 8 word) \s - 1705\ by simp lemma \- (42 :: 8 word) \s - 1705\ by simp lemma \(1 :: 8 word) \s 42\ by simp lemma \(42 :: 8 word) by simp lemma \(- 42 :: 8 word) by simp lemma \(42 :: 8 word) by simp lemma \- (42 :: 8 word) by simp lemma \(1 :: 8 word) by simp lemma \bit (1705 :: 16 word) (Suc (Suc (Suc 0)))\ by simp lemma \bit (1705 :: 16 word) 3\ by simp lemma \\ bit (- 1705 :: 16 word) (Suc (Suc (Suc 0)))\ by simp lemma \\ bit (- 1705 :: 16 word) 3\ by simp lemma \\ bit (1 :: 'a::len word) (Suc (Suc (Suc 0)))\ by simp lemma \\ bit (1 :: 'a::len word) 3\ by simp lemma \(NOT 1705 :: 'a::len word) = - 1706\ by simp lemma \(NOT (- 42 :: 'a::len word)) = 41\ by simp lemma \(NOT 1 :: 'a::len word) = - 2\ by simp lemma \(1705 :: 'a::len word) AND 42 = 40\ by simp lemma \(1705 :: 'a::len word) AND - 42 = 1664\ by simp lemma \(1705 :: 'a::len word) AND 1 = 1\ by simp lemma \- (1705 :: 'a::len word) AND 42 = 2\ by simp lemma \- (1705 :: 'a::len word) AND - 42 = - 1706\ by simp lemma \- (1705 :: 'a::len word) AND 1 = 1\ by simp lemma \(1705 :: 'a::len word) OR 42 = 1707\ by simp lemma \(1705 :: 'a::len word) OR - 42 = - 1\ by simp lemma \(1705 :: 'a::len word) OR 1 = 1705\ by simp lemma \- (1705 :: 'a::len word) OR 42 = - 1665\ by simp lemma \- (1705 :: 'a::len word) OR - 42 = - 41\ by simp lemma \- (1705 :: 'a::len word) OR 1 = - 1705\ by simp lemma \(1705 :: 'a::len word) XOR 42 = 1667\ by simp lemma \(1705 :: 'a::len word) XOR - 42 = - 1665\ by simp lemma \(1705 :: 'a::len word) XOR 1 = 1704\ by simp lemma \- (1705 :: 'a::len word) XOR 42 = - 1667\ by simp lemma \- (1705 :: 'a::len word) XOR - 42 = 1665\ by simp lemma \- (1705 :: 'a::len word) XOR 1 = - 1706\ by simp lemma \push_bit 3 (1705 :: 'a::len word) = 13640\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (1705 :: 'a::len word) = 13640\ by simp lemma \push_bit 3 (- 1705 :: 'a::len word) = - 13640\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (- 1705 :: 'a::len word) = - 13640\ by simp lemma \push_bit 3 (1 :: 'a::len word) = 8\ by simp lemma \push_bit (Suc (Suc (Suc 0))) (1 :: 'a::len word) = 8\ by simp lemma \push_bit 3 (- 1 :: 'a::len word) = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \push_bit (Suc (Suc (Suc 0))) (- 1 :: 'a::len word) = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \(1705 :: 'a::len word) << 3 = 13640\ by simp lemma \(1705 :: 'a::len word) << Suc (Suc (Suc 0)) = 13640\ by simp lemma \(- 1705 :: 'a::len word) << 3 = - 13640\ by simp lemma \(- 1705 :: 'a::len word) << Suc (Suc (Suc 0)) = - 13640\ by simp lemma \(1 :: 'a::len word) << 3 = 8\ by simp lemma \(1 :: 'a::len word) << Suc (Suc (Suc 0)) = 8\ by simp lemma \(- 1 :: 'a::len word) << 3 = - 8\ by (simp add: mask_eq_exp_minus_1) lemma \(- 1 :: 'a::len word) << Suc (Suc (Suc 0)) = - 8\ by simp lemma \drop_bit 3 (1705 :: 16 word) = 213\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 213\ by simp lemma \drop_bit 3 (- 1705 :: 16 word) = 7978\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7978\ by simp lemma \drop_bit 3 (1 :: 16 word) = 0\ by simp lemma \drop_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 0\ by simp lemma \(1705 :: 16 word) >> 3 = 213\ by simp lemma \(1705 :: 16 word) >> Suc (Suc (Suc 0)) = 213\ by simp lemma \(- 1705 :: 16 word) >> 3 = 7978\ by simp lemma \(- 1705 :: 16 word) >> Suc (Suc (Suc 0)) = 7978\ by simp lemma \(1 :: 16 word) >> 3 = 0\ by simp lemma \(1 :: 16 word) >> Suc (Suc (Suc 0)) = 0\ by simp lemma \signed_drop_bit 3 (1705 :: 16 word) = 213\ by simp lemma \signed_drop_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 213\ by simp lemma \signed_drop_bit 3 (- 1705 :: 16 word) = - 214\ by simp lemma \signed_drop_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = - 214\ by simp lemma \signed_drop_bit 3 (1 :: 16 word) = 0\ by simp lemma \signed_drop_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 0\ by simp lemma \(1705 :: 16 word) >>> 3 = 213\ by simp lemma \(1705 :: 16 word) >>> Suc (Suc (Suc 0)) = 213\ by simp lemma \(- 1705 :: 16 word) >>> 3 = - 214\ by simp lemma \(- 1705 :: 16 word) >>> Suc (Suc (Suc 0)) = - 214\ by simp lemma \(1 :: 16 word) >>> 3 = 0\ by simp lemma \(1 :: 16 word) >>> Suc (Suc (Suc 0)) = 0\ by simp lemma \take_bit 3 (1705 :: 16 word) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = 1\ by (simp flip: add_2_eq_Suc) lemma \take_bit 3 (- 1705 :: 16 word) = 7\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7\ by (simp flip: add_2_eq_Suc) lemma \take_bit 3 (1 :: 16 word) = 1\ by simp lemma \take_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 1\ by simp lemma \take_bit 3 (- 1 :: 16 word) = 7\ by (simp add: mask_eq_exp_minus_1) lemma \take_bit (Suc (Suc (Suc 0))) (- 1 :: 16 word) = 7\ by (simp add: mask_eq_exp_minus_1) lemma \signed_take_bit 3 (1705 :: 16 word) = - 7\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (1705 :: 16 word) = - 7\ by simp lemma \signed_take_bit 3 (- 1705 :: 16 word) = 7\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (- 1705 :: 16 word) = 7\ by simp lemma \signed_take_bit 3 (1 :: 16 word) = 1\ by simp lemma \signed_take_bit (Suc (Suc (Suc 0))) (1 :: 16 word) = 1\ by simp lemma \(1705 :: 16 word) div 42 = 40\ by simp lemma \(- 1705 :: 16 word) div 42 = 1519\ by simp lemma \(1705 :: 16 word) div - 42 = 0\ by simp lemma \(- 1705 :: 16 word) div - 42 = 0\ by simp lemma \(1705 :: 16 word) div 1 = 1705\ by simp lemma \(1705 :: 16 word) div - 1 = 0\ by simp lemma \(1 :: 16 word) div 42 = 0\ by simp lemma \(- 1 :: 16 word) div 42 = 1560\ by simp lemma \(1705 :: 16 word) mod 42 = 25\ by simp lemma \(- 1705 :: 16 word) mod 42 = 33\ by simp lemma \(1705 :: 16 word) mod - 42 = 1705\ by simp lemma \(- 1705 :: 16 word) mod - 42 = 63831\ by simp lemma \(1705 :: 16 word) mod 1 = 0\ by simp lemma \(1705 :: 16 word) mod - 1 = 1705\ by simp lemma \(1 :: 16 word) mod 42 = 1\ by simp lemma \(- 1 :: 16 word) mod 42 = 15\ by simp lemma \(1705 :: 16 word) sdiv 42 = 40\ by simp lemma \(- 1705 :: 16 word) sdiv 42 = 65496\ by simp lemma \(1705 :: 16 word) sdiv - 42 = 65496\ by simp lemma \(- 1705 :: 16 word) sdiv - 42 = 40\ by simp lemma \(1705 :: 16 word) sdiv 1 = 1705\ by simp lemma \(1705 :: 16 word) sdiv - 1 = 63831\ by simp lemma \(1 :: 16 word) sdiv 42 = 0\ by simp lemma \(- 1 :: 16 word) sdiv 42 = 0\ by simp lemma \(1705 :: 16 word) smod 42 = 25\ by simp lemma \(- 1705 :: 16 word) smod 42 = 65511\ by simp lemma \(1705 :: 16 word) smod - 42 = 25\ by simp lemma \(- 1705 :: 16 word) smod - 42 = 65511\ by simp lemma \(1705 :: 16 word) smod 1 = 0\ by simp lemma \(1705 :: 16 word) smod - 1 = 0\ by simp lemma \(1 :: 16 word) smod 42 = 1\ by simp lemma \(- 1 :: 16 word) smod 42 = 65535\ by simp text "modulus" lemma "(27 :: 4 word) = -5" by simp lemma "(27 :: 4 word) = 11" by simp lemma "27 \ (11 :: 6 word)" by simp text "signed" lemma "(127 :: 6 word) = -1" by simp text "number ring simps" lemma "27 + 11 = (38::'a::len word)" "27 + 11 = (6::5 word)" "7 * 3 = (21::'a::len word)" "11 - 27 = (-16::'a::len word)" "- (- 11) = (11::'a::len word)" "-40 + 1 = (-39::'a::len word)" by simp_all lemma "word_pred 2 = 1" by simp lemma "word_succ (- 3) = -2" by simp lemma "23 < (27::8 word)" by simp lemma "23 \ (27::8 word)" by simp lemma "\ 23 < (27::2 word)" by simp lemma "0 < (4::3 word)" by simp lemma "1 < (4::3 word)" by simp lemma "0 < (1::3 word)" by simp text "ring operations" lemma "a + 2 * b + c - b = (b + c) + (a :: 32 word)" by simp text "casting" lemma "uint (234567 :: 10 word) = 71" by simp lemma "uint (-234567 :: 10 word) = 953" by simp lemma "sint (234567 :: 10 word) = 71" by simp lemma "sint (-234567 :: 10 word) = -71" by simp lemma "uint (1 :: 10 word) = 1" by simp lemma "unat (-234567 :: 10 word) = 953" by simp lemma "unat (1 :: 10 word) = 1" by simp lemma "ucast (0b1010 :: 4 word) = (0b10 :: 2 word)" by simp lemma "ucast (0b1010 :: 4 word) = (0b1010 :: 10 word)" by simp lemma "scast (0b1010 :: 4 word) = (0b111010 :: 6 word)" by simp lemma "ucast (1 :: 4 word) = (1 :: 2 word)" by simp text "reducing goals to nat or int and arith:" lemma "i < x \ i < i + 1" for i x :: "'a::len word" by unat_arith lemma "i < x \ i < i + 1" for i x :: "'a::len word" by unat_arith text "bit operations" lemma "0b110 AND 0b101 = (0b100 :: 32 word)" by simp lemma "0b110 OR 0b011 = (0b111 :: 8 word)" by simp lemma "0xF0 XOR 0xFF = (0x0F :: 8 word)" by simp lemma "NOT (0xF0 :: 16 word) = 0xFF0F" by simp lemma "0 AND 5 = (0 :: 8 word)" by simp lemma "1 AND 1 = (1 :: 8 word)" by simp lemma "1 AND 0 = (0 :: 8 word)" by simp lemma "1 AND 5 = (1 :: 8 word)" by simp lemma "1 OR 6 = (7 :: 8 word)" by simp lemma "1 OR 1 = (1 :: 8 word)" by simp lemma "1 XOR 7 = (6 :: 8 word)" by simp lemma "1 XOR 1 = (0 :: 8 word)" by simp lemma "NOT 1 = (254 :: 8 word)" by simp lemma "NOT 0 = (255 :: 8 word)" by simp lemma "(-1 :: 32 word) = 0xFFFFFFFF" by simp lemma "bit (0b0010 :: 4 word) 1" by simp lemma "\ bit (0b0010 :: 4 word) 0" by simp lemma "\ bit (0b1000 :: 3 word) 4" by simp lemma "\ bit (1 :: 3 word) 2" by simp lemma "bit (0b11000 :: 10 word) n = (n = 4 \ n = 3)" by (auto simp add: bit_numeral_rec bit_1_iff split: nat.splits) lemma "set_bit 55 7 True = (183::'a::len word)" by simp lemma "set_bit 0b0010 7 True = (0b10000010::'a::len word)" by simp lemma "set_bit 0b0010 1 False = (0::'a::len word)" by simp lemma "set_bit 1 3 True = (0b1001::'a::len word)" by simp lemma "set_bit 1 0 False = (0::'a::len word)" by simp lemma "set_bit 0 3 True = (0b1000::'a::len word)" by simp lemma "set_bit 0 3 False = (0::'a::len word)" by simp lemma "odd (0b0101::'a::len word)" by simp lemma "even (0b1000::'a::len word)" by simp lemma "odd (1::'a::len word)" by simp lemma "even (0::'a::len word)" by simp lemma "\ msb (0b0101::4 word)" by simp lemma "msb (0b1000::4 word)" by simp lemma "\ msb (1::4 word)" by simp lemma "\ msb (0::4 word)" by simp lemma "word_cat (27::4 word) (27::8 word) = (2843::'a::len word)" by simp lemma "word_cat (0b0011::4 word) (0b1111::6word) = (0b0011001111 :: 10 word)" by simp lemma "0b1011 << 2 = (0b101100::'a::len word)" by simp lemma "0b1011 >> 2 = (0b10::8 word)" by simp lemma "0b1011 >>> 2 = (0b10::8 word)" by simp lemma "1 << 2 = (0b100::'a::len word)" apply simp? oops lemma "slice 3 (0b101111::6 word) = (0b101::3 word)" by simp lemma "slice 3 (1::6 word) = (0::3 word)" apply simp? oops lemma "word_rotr 2 0b0110 = (0b1001::4 word)" by simp lemma "word_rotl 1 0b1110 = (0b1101::4 word)" by simp lemma "word_roti 2 0b1110 = (0b1011::4 word)" by simp lemma "word_roti (- 2) 0b0110 = (0b1001::4 word)" by simp lemma "word_rotr 2 0 = (0::4 word)" by simp lemma "word_rotr 2 1 = (0b0100::4 word)" apply simp? oops lemma "word_rotl 2 1 = (0b0100::4 word)" apply simp? oops lemma "word_roti (- 2) 1 = (0b0100::4 word)" apply simp? oops lemma "(x AND 0xff00) OR (x AND 0x00ff) = (x::16 word)" proof - have "(x AND 0xff00) OR (x AND 0x00ff) = x AND (0xff00 OR 0x00ff)" by (simp only: word_ao_dist2) also have "0xff00 OR 0x00ff = (-1::16 word)" by simp also have "x AND -1 = x" by simp finally show ?thesis . qed lemma "word_next (2:: 8 word) = 3" by eval lemma "word_next (255:: 8 word) = 255" by eval lemma "word_prev (2:: 8 word) = 1" by eval lemma "word_prev (0:: 8 word) = 0" by eval text \singed division\ lemma "( 4 :: 32 word) sdiv 4 = 1" "(-4 :: 32 word) sdiv 4 = -1" "(-3 :: 32 word) sdiv 4 = 0" "( 3 :: 32 word) sdiv -4 = 0" "(-3 :: 32 word) sdiv -4 = 0" "(-5 :: 32 word) sdiv -4 = 1" "( 5 :: 32 word) sdiv -4 = -1" by (simp_all add: sdiv_word_def signed_divide_int_def) lemma "( 4 :: 32 word) smod 4 = 0" "( 3 :: 32 word) smod 4 = 3" "(-3 :: 32 word) smod 4 = -3" "( 3 :: 32 word) smod -4 = 3" "(-3 :: 32 word) smod -4 = -3" "(-5 :: 32 word) smod -4 = -1" "( 5 :: 32 word) smod -4 = 1" by (simp_all add: smod_word_def signed_modulo_int_def signed_divide_int_def) text \comparison\ lemma "1 < (1024::32 word) \ 1 \ (1024::32 word)" by simp text "bool lists" lemma "of_bl [True, False, True, True] = (0b1011::'a::len word)" by simp lemma "to_bl (0b110::4 word) = [False, True, True, False]" by simp lemma "of_bl (replicate 32 True) = (0xFFFFFFFF::32 word)" by (simp add: numeral_eq_Suc) text "proofs using bitwise expansion" lemma "(x AND 0xff00) OR (x AND 0x00ff) = (x::16 word)" by word_bitwise lemma "(x AND NOT 3) >> 4 << 2 = ((x >> 2) AND NOT 3)" for x :: "10 word" by word_bitwise lemma "((x AND -8) >> 3) AND 7 = (x AND 56) >> 3" for x :: "12 word" by word_bitwise text "some problems require further reasoning after bit expansion" lemma "x \ 42 \ x \ 89" for x :: "8 word" apply word_bitwise apply blast done lemma "(x AND 1023) = 0 \ x \ -1024" for x :: \32 word\ apply word_bitwise apply clarsimp done text "operations like shifts by non-numerals will expose some internal list representations but may still be easy to solve" lemma shiftr_overflow: "32 \ a \ b >> a = 0" for b :: \32 word\ apply word_bitwise apply simp done (* testing for presence of word_bitwise *) lemma "((x :: 32 word) >> 3) AND 7 = (x AND 56) >> 3" by word_bitwise end end