1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 (* ********************************************************************** *)
16 (* Progetto FreeScale *)
19 (* Cosimo Oliboni, oliboni@cs.unibo.it *)
21 (* Questo materiale fa parte della tesi: *)
22 (* "Formalizzazione Interattiva dei Microcontroller a 8bit FreeScale" *)
24 (* data ultima modifica 15/11/2007 *)
25 (* ********************************************************************** *)
27 include "freescale/byte8.ma".
33 nrecord word16 : Type ≝
39 ndefinition word16_ind : ΠP:word16 → Prop.(Πb:byte8.Πb1:byte8.P (mk_word16 b b1)) → Πw:word16.P w ≝
40 λP:word16 → Prop.λf:Πb:byte8.Πb1:byte8.P (mk_word16 b b1).λw:word16.
41 match w with [ mk_word16 (b:byte8) (b1:byte8) ⇒ f b b1 ].
43 ndefinition word16_rec : ΠP:word16 → Set.(Πb:byte8.Πb1:byte8.P (mk_word16 b b1)) → Πw:word16.P w ≝
44 λP:word16 → Set.λf:Πb:byte8.Πb1:byte8.P (mk_word16 b b1).λw:word16.
45 match w with [ mk_word16 (b:byte8) (b1:byte8) ⇒ f b b1 ].
47 ndefinition word16_rect : ΠP:word16 → Type.(Πb:byte8.Πb1:byte8.P (mk_word16 b b1)) → Πw:word16.P w ≝
48 λP:word16 → Type.λf:Πb:byte8.Πb1:byte8.P (mk_word16 b b1).λw:word16.
49 match w with [ mk_word16 (b:byte8) (b1:byte8) ⇒ f b b1 ].
51 ndefinition w16h ≝ λw:word16.match w with [ mk_word16 x _ ⇒ x ].
52 ndefinition w16l ≝ λw:word16.match w with [ mk_word16 _ x ⇒ x ].
55 notation "〈x:y〉" non associative with precedence 80
56 for @{ 'mk_word16 $x $y }.
57 interpretation "mk_word16" 'mk_word16 x y = (mk_word16 x y).
60 ndefinition eq_w16 ≝ λw1,w2.(eq_b8 (w16h w1) (w16h w2)) ⊗ (eq_b8 (w16l w1) (w16l w2)).
64 λw1,w2:word16.match lt_b8 (w16h w1) (w16h w2) with
66 | false ⇒ match gt_b8 (w16h w1) (w16h w2) with
68 | false ⇒ lt_b8 (w16l w1) (w16l w2) ]].
71 ndefinition le_w16 ≝ λw1,w2:word16.(eq_w16 w1 w2) ⊕ (lt_w16 w1 w2).
74 ndefinition gt_w16 ≝ λw1,w2:word16.⊖ (le_w16 w1 w2).
77 ndefinition ge_w16 ≝ λw1,w2:word16.⊖ (lt_w16 w1 w2).
81 λw1,w2:word16.mk_word16 (and_b8 (w16h w1) (w16h w2)) (and_b8 (w16l w1) (w16l w2)).
85 λw1,w2:word16.mk_word16 (or_b8 (w16h w1) (w16h w2)) (or_b8 (w16l w1) (w16l w2)).
89 λw1,w2:word16.mk_word16 (xor_b8 (w16h w1) (w16h w2)) (xor_b8 (w16l w1) (w16l w2)).
91 (* operatore rotazione destra con carry *)
93 λw:word16.λc:bool.match rcr_b8 (w16h w) c with
94 [ pair wh' c' ⇒ match rcr_b8 (w16l w) c' with
95 [ pair wl' c'' ⇒ pair ?? (mk_word16 wh' wl') c'' ]].
97 (* operatore shift destro *)
99 λw:word16.match rcr_b8 (w16h w) false with
100 [ pair wh' c' ⇒ match rcr_b8 (w16l w) c' with
101 [ pair wl' c'' ⇒ pair ?? (mk_word16 wh' wl') c'' ]].
103 (* operatore rotazione destra *)
104 ndefinition ror_w16 ≝
105 λw:word16.match rcr_b8 (w16h w) false with
106 [ pair wh' c' ⇒ match rcr_b8 (w16l w) c' with
107 [ pair wl' c'' ⇒ match c'' with
108 [ true ⇒ mk_word16 (or_b8 (mk_byte8 x8 x0) wh') wl'
109 | false ⇒ mk_word16 wh' wl' ]]].
111 (* operatore rotazione destra n-volte *)
112 nlet rec ror_w16_n (w:word16) (n:nat) on n ≝
115 | S n' ⇒ ror_w16_n (ror_w16 w) n' ].
117 (* operatore rotazione sinistra con carry *)
118 ndefinition rcl_w16 ≝
119 λw:word16.λc:bool.match rcl_b8 (w16l w) c with
120 [ pair wl' c' ⇒ match rcl_b8 (w16h w) c' with
121 [ pair wh' c'' ⇒ pair ?? (mk_word16 wh' wl') c'' ]].
123 (* operatore shift sinistro *)
124 ndefinition shl_w16 ≝
125 λw:word16.match rcl_b8 (w16l w) false with
126 [ pair wl' c' ⇒ match rcl_b8 (w16h w) c' with
127 [ pair wh' c'' ⇒ pair ?? (mk_word16 wh' wl') c'' ]].
129 (* operatore rotazione sinistra *)
130 ndefinition rol_w16 ≝
131 λw:word16.match rcl_b8 (w16l w) false with
132 [ pair wl' c' ⇒ match rcl_b8 (w16h w) c' with
133 [ pair wh' c'' ⇒ match c'' with
134 [ true ⇒ mk_word16 wh' (or_b8 (mk_byte8 x0 x1) wl')
135 | false ⇒ mk_word16 wh' wl' ]]].
137 (* operatore rotazione sinistra n-volte *)
138 nlet rec rol_w16_n (w:word16) (n:nat) on n ≝
141 | S n' ⇒ rol_w16_n (rol_w16 w) n' ].
143 (* operatore not/complemento a 1 *)
144 ndefinition not_w16 ≝
145 λw:word16.mk_word16 (not_b8 (w16h w)) (not_b8 (w16l w)).
147 (* operatore somma con data+carry → data+carry *)
148 ndefinition plus_w16_dc_dc ≝
149 λw1,w2:word16.λc:bool.
150 match plus_b8_dc_dc (w16l w1) (w16l w2) c with
151 [ pair l c ⇒ match plus_b8_dc_dc (w16h w1) (w16h w2) c with
152 [ pair h c' ⇒ pair ?? 〈h:l〉 c' ]].
154 (* operatore somma con data+carry → data *)
155 ndefinition plus_w16_dc_d ≝
156 λw1,w2:word16.λc:bool.
157 match plus_b8_dc_dc (w16l w1) (w16l w2) c with
158 [ pair l c ⇒ 〈plus_b8_dc_d (w16h w1) (w16h w2) c:l〉 ].
160 (* operatore somma con data+carry → c *)
161 ndefinition plus_w16_dc_c ≝
162 λw1,w2:word16.λc:bool.
163 plus_b8_dc_c (w16h w1) (w16h w2) (plus_b8_dc_c (w16l w1) (w16l w2) c).
165 (* operatore somma con data → data+carry *)
166 ndefinition plus_w16_d_dc ≝
168 match plus_b8_d_dc (w16l w1) (w16l w2) with
169 [ pair l c ⇒ match plus_b8_dc_dc (w16h w1) (w16h w2) c with
170 [ pair h c' ⇒ pair ?? 〈h:l〉 c' ]].
172 (* operatore somma con data → data *)
173 ndefinition plus_w16_d_d ≝
175 match plus_b8_d_dc (w16l w1) (w16l w2) with
176 [ pair l c ⇒ 〈plus_b8_dc_d (w16h w1) (w16h w2) c:l〉 ].
178 (* operatore somma con data → c *)
179 ndefinition plus_w16_d_c ≝
181 plus_b8_dc_c (w16h w1) (w16h w2) (plus_b8_d_c (w16l w1) (w16l w2)).
183 (* operatore Most Significant Bit *)
184 ndefinition MSB_w16 ≝ λw:word16.eq_ex x8 (and_ex x8 (b8h (w16h w))).
186 (* word → naturali *)
187 ndefinition nat_of_word16 ≝ λw:word16. 256 * (nat_of_byte8 (w16h w)) + (nat_of_byte8 (w16l w)).
189 (* operatore predecessore *)
190 ndefinition pred_w16 ≝
191 λw:word16.match eq_b8 (w16l w) (mk_byte8 x0 x0) with
192 [ true ⇒ mk_word16 (pred_b8 (w16h w)) (pred_b8 (w16l w))
193 | false ⇒ mk_word16 (w16h w) (pred_b8 (w16l w)) ].
195 (* operatore successore *)
196 ndefinition succ_w16 ≝
197 λw:word16.match eq_b8 (w16l w) (mk_byte8 xF xF) with
198 [ true ⇒ mk_word16 (succ_b8 (w16h w)) (succ_b8 (w16l w))
199 | false ⇒ mk_word16 (w16h w) (succ_b8 (w16l w)) ].
201 (* operatore neg/complemento a 2 *)
202 ndefinition compl_w16 ≝
203 λw:word16.match MSB_w16 w with
204 [ true ⇒ succ_w16 (not_w16 w)
205 | false ⇒ not_w16 (pred_w16 w) ].
208 operatore moltiplicazione senza segno: b*b=[0x0000,0xFE01]
209 ... in pratica (〈a,b〉*〈c,d〉) = (a*c)<<8+(a*d)<<4+(b*c)<<4+(b*d)
212 λb1,b2:byte8.match b1 with
213 [ mk_byte8 b1h b1l ⇒ match b2 with
214 [ mk_byte8 b2h b2l ⇒ match mul_ex b1l b2l with
215 [ mk_byte8 t1_h t1_l ⇒ match mul_ex b1h b2l with
216 [ mk_byte8 t2_h t2_l ⇒ match mul_ex b2h b1l with
217 [ mk_byte8 t3_h t3_l ⇒ match mul_ex b1h b2h with
218 [ mk_byte8 t4_h t4_l ⇒
221 (plus_w16_d_d 〈〈x0,t3_h〉:〈t3_l,x0〉〉 〈〈x0,t2_h〉:〈t2_l,x0〉〉) 〈〈t4_h,t4_l〉:〈x0,x0〉〉)〈〈x0,x0〉:〈t1_h,t1_l〉〉
224 (* divisione senza segno (secondo la logica delle ALU): (quoziente resto) overflow *)
225 nlet rec div_b8_aux (divd:word16) (divs:word16) (molt:byte8) (q:byte8) (c:nat) on c ≝
226 let w' ≝ plus_w16_d_d divd (compl_w16 divs) in
228 [ O ⇒ match le_w16 divs divd with
229 [ true ⇒ triple ??? (or_b8 molt q) (w16l w') (⊖ (eq_b8 (w16h w') 〈x0,x0〉))
230 | false ⇒ triple ??? q (w16l divd) (⊖ (eq_b8 (w16h divd) 〈x0,x0〉)) ]
231 | S c' ⇒ match le_w16 divs divd with
232 [ true ⇒ div_b8_aux w' (ror_w16 divs) (ror_b8 molt) (or_b8 molt q) c'
233 | false ⇒ div_b8_aux divd (ror_w16 divs) (ror_b8 molt) q c' ]].
236 λw:word16.λb:byte8.match eq_b8 b 〈x0,x0〉 with
238 la combinazione n/0 e' illegale, segnala solo overflow senza dare risultato
240 [ true ⇒ triple ??? 〈xF,xF〉 (w16l w) true
241 | false ⇒ match eq_w16 w 〈〈x0,x0〉:〈x0,x0〉〉 with
242 (* 0 diviso qualsiasi cosa diverso da 0 da' q=0 r=0 o=false *)
243 [ true ⇒ triple ??? 〈x0,x0〉 〈x0,x0〉 false
244 (* 1) e' una divisione sensata che produrra' overflow/risultato *)
245 (* 2) parametri: dividendo, divisore, moltiplicatore, quoziente, contatore *)
246 (* 3) ad ogni ciclo il divisore e il moltiplicatore vengono scalati di 1 a dx *)
247 (* 4) il moltiplicatore e' la quantita' aggiunta al quoziente se il divisore *)
248 (* puo' essere sottratto al dividendo *)
249 | false ⇒ div_b8_aux w (rol_w16_n 〈〈x0,x0〉:b〉 7) 〈x8,x0〉 〈x0,x0〉 7 ]].
251 (* operatore x in [inf,sup] *)
252 ndefinition in_range ≝
253 λx,inf,sup:word16.(le_w16 inf sup) ⊗ (ge_w16 x inf) ⊗ (le_w16 x sup).
255 (* iteratore sulle word *)
256 ndefinition forall_word16 ≝
260 P (mk_word16 bh bl ))).