diff options
Diffstat (limited to 'theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v')
| -rw-r--r-- | theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v | 324 |
1 files changed, 162 insertions, 162 deletions
diff --git a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v index 075aef59..9204b4e0 100644 --- a/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v +++ b/theories/Numbers/Cyclic/DoubleCyclic/DoubleDiv.v @@ -8,7 +8,7 @@ (* Benjamin Gregoire, Laurent Thery, INRIA, 2007 *) (************************************************************************) -(*i $Id: DoubleDiv.v 10964 2008-05-22 11:08:13Z letouzey $ i*) +(*i $Id$ i*) Set Implicit Arguments. @@ -20,7 +20,7 @@ Require Import DoubleDivn1. Require Import DoubleAdd. Require Import DoubleSub. -Open Local Scope Z_scope. +Local Open Scope Z_scope. Ltac zarith := auto with zarith. @@ -41,13 +41,13 @@ Section POS_MOD. Variable ww_zdigits : zn2z w. - Definition ww_pos_mod p x := + Definition ww_pos_mod p x := let zdigits := w_0W w_zdigits in match x with | W0 => W0 | WW xh xl => match ww_compare p zdigits with - | Eq => w_WW w_0 xl + | Eq => w_WW w_0 xl | Lt => w_WW w_0 (w_pos_mod (low p) xl) | Gt => match ww_compare p ww_zdigits with @@ -87,7 +87,7 @@ Section POS_MOD. | Lt => [[x]] < [[y]] | Gt => [[x]] > [[y]] end. - Variable spec_ww_sub: forall x y, + Variable spec_ww_sub: forall x y, [[ww_sub x y]] = ([[x]] - [[y]]) mod wwB. Variable spec_zdigits : [| w_zdigits |] = Zpos w_digits. @@ -106,7 +106,7 @@ Section POS_MOD. unfold ww_pos_mod; case w1. simpl; rewrite Zmod_small; split; auto with zarith. intros xh xl; generalize (spec_ww_compare p (w_0W w_zdigits)); - case ww_compare; + case ww_compare; rewrite spec_w_0W; rewrite spec_zdigits; fold wB; intros H1. rewrite H1; simpl ww_to_Z. @@ -135,13 +135,13 @@ Section POS_MOD. autorewrite with w_rewrite rm10. rewrite Zmod_mod; auto with zarith. generalize (spec_ww_compare p ww_zdigits); - case ww_compare; rewrite spec_ww_zdigits; + case ww_compare; rewrite spec_ww_zdigits; rewrite spec_zdigits; intros H2. replace (2^[[p]]) with wwB. rewrite Zmod_small; auto with zarith. unfold base; rewrite H2. rewrite spec_ww_digits; auto. - assert (HH0: [|low (ww_sub p (w_0W w_zdigits))|] = + assert (HH0: [|low (ww_sub p (w_0W w_zdigits))|] = [[p]] - Zpos w_digits). rewrite spec_low. rewrite spec_ww_sub. @@ -152,11 +152,11 @@ generalize (spec_ww_compare p ww_zdigits); apply Zlt_le_trans with (Zpos w_digits); auto with zarith. unfold base; apply Zpower2_le_lin; auto with zarith. exists wB; unfold base; rewrite <- Zpower_exp; auto with zarith. - rewrite spec_ww_digits; + rewrite spec_ww_digits; apply f_equal with (f := Zpower 2); rewrite Zpos_xO; auto with zarith. simpl ww_to_Z; autorewrite with w_rewrite. rewrite spec_pos_mod; rewrite HH0. - pattern [|xh|] at 2; + pattern [|xh|] at 2; rewrite Z_div_mod_eq with (b := 2 ^ ([[p]] - Zpos w_digits)); auto with zarith. rewrite (fun x => (Zmult_comm (2 ^ x))); rewrite Zmult_plus_distr_l. @@ -196,7 +196,7 @@ generalize (spec_ww_compare p ww_zdigits); split; auto with zarith. rewrite Zpos_xO; auto with zarith. Qed. - + End POS_MOD. Section DoubleDiv32. @@ -222,24 +222,24 @@ Section DoubleDiv32. match w_compare a1 b1 with | Lt => let (q,r) := w_div21 a1 a2 b1 in - match ww_sub_c (w_WW r a3) (w_mul_c q b2) with + match ww_sub_c (w_WW r a3) (w_mul_c q b2) with | C0 r1 => (q,r1) | C1 r1 => let q := w_pred q in - ww_add_c_cont w_WW w_add_c w_add_carry_c + ww_add_c_cont w_WW w_add_c w_add_carry_c (fun r2=>(w_pred q, ww_add w_add_c w_add w_add_carry r2 (WW b1 b2))) (fun r2 => (q,r2)) r1 (WW b1 b2) end | Eq => - ww_add_c_cont w_WW w_add_c w_add_carry_c + ww_add_c_cont w_WW w_add_c w_add_carry_c (fun r => (w_Bm2, ww_add w_add_c w_add w_add_carry r (WW b1 b2))) (fun r => (w_Bm1,r)) (WW (w_sub a2 b2) a3) (WW b1 b2) | Gt => (w_0, W0) (* cas absurde *) end. - (* Proof *) + (* Proof *) Variable w_digits : positive. Variable w_to_Z : w -> Z. @@ -253,8 +253,8 @@ Section DoubleDiv32. (interp_carry (-1) wB w_to_Z c) (at level 0, x at level 99). Notation "[[ x ]]" := (ww_to_Z w_digits w_to_Z x)(at level 0, x at level 99). - Notation "[-[ c ]]" := - (interp_carry (-1) wwB (ww_to_Z w_digits w_to_Z) c) + Notation "[-[ c ]]" := + (interp_carry (-1) wwB (ww_to_Z w_digits w_to_Z) c) (at level 0, x at level 99). @@ -273,7 +273,7 @@ Section DoubleDiv32. | Gt => [|x|] > [|y|] end. Variable spec_w_add_c : forall x y, [+|w_add_c x y|] = [|x|] + [|y|]. - Variable spec_w_add_carry_c : + Variable spec_w_add_carry_c : forall x y, [+|w_add_carry_c x y|] = [|x|] + [|y|] + 1. Variable spec_w_add : forall x y, [|w_add x y|] = ([|x|] + [|y|]) mod wB. @@ -315,8 +315,8 @@ Section DoubleDiv32. wB/2 <= [|b1|] -> [[WW a1 a2]] < [[WW b1 b2]] -> let (q,r) := w_div32 a1 a2 a3 b1 b2 in - [|a1|] * wwB + [|a2|] * wB + [|a3|] = - [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ + [|a1|] * wwB + [|a2|] * wB + [|a3|] = + [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ 0 <= [[r]] < [|b1|] * wB + [|b2|]. Proof. intros a1 a2 a3 b1 b2 Hle Hlt. @@ -327,17 +327,17 @@ Section DoubleDiv32. match w_compare a1 b1 with | Lt => let (q,r) := w_div21 a1 a2 b1 in - match ww_sub_c (w_WW r a3) (w_mul_c q b2) with + match ww_sub_c (w_WW r a3) (w_mul_c q b2) with | C0 r1 => (q,r1) | C1 r1 => let q := w_pred q in - ww_add_c_cont w_WW w_add_c w_add_carry_c + ww_add_c_cont w_WW w_add_c w_add_carry_c (fun r2=>(w_pred q, ww_add w_add_c w_add w_add_carry r2 (WW b1 b2))) (fun r2 => (q,r2)) r1 (WW b1 b2) end | Eq => - ww_add_c_cont w_WW w_add_c w_add_carry_c + ww_add_c_cont w_WW w_add_c w_add_carry_c (fun r => (w_Bm2, ww_add w_add_c w_add w_add_carry r (WW b1 b2))) (fun r => (w_Bm1,r)) (WW (w_sub a2 b2) a3) (WW b1 b2) @@ -360,7 +360,7 @@ Section DoubleDiv32. [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ 0 <= [[r]] < [|b1|] * wB + [|b2|]);eauto. rewrite H0;intros r. - repeat + repeat (rewrite spec_ww_add;eauto || rewrite spec_w_Bm1 || rewrite spec_w_Bm2); simpl ww_to_Z;try rewrite Zmult_1_l;intros H1. assert (0<= ([[r]] + ([|b1|] * wB + [|b2|])) - wwB < [|b1|] * wB + [|b2|]). @@ -385,7 +385,7 @@ Section DoubleDiv32. 1 ([[r]] + ([|b1|] * wB + [|b2|]) - wwB));zarith;try (ring;fail). split. rewrite H1;rewrite Hcmp;ring. trivial. Spec_ww_to_Z (WW b1 b2). simpl in HH4;zarith. - rewrite H0;intros r;repeat + rewrite H0;intros r;repeat (rewrite spec_w_Bm1 || rewrite spec_w_Bm2); simpl ww_to_Z;try rewrite Zmult_1_l;intros H1. assert ([[r]]=([|a2|]-[|b2|])*wB+[|a3|]+([|b1|]*wB+[|b2|])). zarith. @@ -409,7 +409,7 @@ Section DoubleDiv32. as [r1|r1];repeat (rewrite spec_w_WW || rewrite spec_mul_c); unfold interp_carry;intros H1. rewrite H1. - split. ring. split. + split. ring. split. rewrite <- H1;destruct (spec_ww_to_Z w_digits w_to_Z spec_to_Z r1);trivial. apply Zle_lt_trans with ([|r|] * wB + [|a3|]). assert ( 0 <= [|q|] * [|b2|]);zarith. @@ -418,7 +418,7 @@ Section DoubleDiv32. rewrite <- H1;ring. Spec_ww_to_Z r1; assert (0 <= [|r|]*wB). zarith. assert (0 < [|q|] * [|b2|]). zarith. - assert (0 < [|q|]). + assert (0 < [|q|]). apply Zmult_lt_0_reg_r_2 with [|b2|];zarith. eapply spec_ww_add_c_cont with (P := fun (x y:zn2z w) (res:w*zn2z w) => @@ -440,18 +440,18 @@ Section DoubleDiv32. wwB * 1 + ([|r|] * wB + [|a3|] - [|q|] * [|b2|] + 2 * ([|b1|] * wB + [|b2|]))). rewrite H7;rewrite H2;ring. - assert - ([|r|]*wB + [|a3|] - [|q|]*[|b2|] + 2 * ([|b1|]*wB + [|b2|]) + assert + ([|r|]*wB + [|a3|] - [|q|]*[|b2|] + 2 * ([|b1|]*wB + [|b2|]) < [|b1|]*wB + [|b2|]). Spec_ww_to_Z r2;omega. Spec_ww_to_Z (WW b1 b2). simpl in HH5. - assert - (0 <= [|r|]*wB + [|a3|] - [|q|]*[|b2|] + 2 * ([|b1|]*wB + [|b2|]) + assert + (0 <= [|r|]*wB + [|a3|] - [|q|]*[|b2|] + 2 * ([|b1|]*wB + [|b2|]) < wwB). split;try omega. replace (2*([|b1|]*wB+[|b2|])) with ((2*[|b1|])*wB+2*[|b2|]). 2:ring. assert (H12:= wB_div2 Hle). assert (wwB <= 2 * [|b1|] * wB). rewrite wwB_wBwB; rewrite Zpower_2; zarith. omega. - rewrite <- (Zmod_unique + rewrite <- (Zmod_unique ([[r2]] + ([|b1|] * wB + [|b2|])) wwB 1 @@ -486,7 +486,7 @@ Section DoubleDiv21. Definition ww_div21 a1 a2 b := match a1 with - | W0 => + | W0 => match ww_compare a2 b with | Gt => (ww_1, ww_sub a2 b) | Eq => (ww_1, W0) @@ -529,8 +529,8 @@ Section DoubleDiv21. Notation wwB := (base (ww_digits w_digits)). Notation "[| x |]" := (w_to_Z x) (at level 0, x at level 99). Notation "[[ x ]]" := (ww_to_Z w_digits w_to_Z x)(at level 0, x at level 99). - Notation "[-[ c ]]" := - (interp_carry (-1) wwB (ww_to_Z w_digits w_to_Z) c) + Notation "[-[ c ]]" := + (interp_carry (-1) wwB (ww_to_Z w_digits w_to_Z) c) (at level 0, x at level 99). Variable spec_w_0 : [|w_0|] = 0. @@ -540,8 +540,8 @@ Section DoubleDiv21. wB/2 <= [|b1|] -> [[WW a1 a2]] < [[WW b1 b2]] -> let (q,r) := w_div32 a1 a2 a3 b1 b2 in - [|a1|] * wwB + [|a2|] * wB + [|a3|] = - [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ + [|a1|] * wwB + [|a2|] * wB + [|a3|] = + [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ 0 <= [[r]] < [|b1|] * wB + [|b2|]. Variable spec_ww_1 : [[ww_1]] = 1. Variable spec_ww_compare : forall x y, @@ -591,10 +591,10 @@ Section DoubleDiv21. intros Hlt H; match goal with |-context [w_div32 ?X ?Y ?Z ?T ?U] => generalize (@spec_w_div32 X Y Z T U); case (w_div32 X Y Z T U); intros q1 r H0 - end; (assert (Eq1: wB / 2 <= [|b1|]);[ + end; (assert (Eq1: wB / 2 <= [|b1|]);[ apply (@beta_lex (wB / 2) 0 [|b1|] [|b2|] wB); auto with zarith; autorewrite with rm10;repeat rewrite (Zmult_comm wB); - rewrite <- wwB_div_2; trivial + rewrite <- wwB_div_2; trivial | generalize (H0 Eq1 Hlt);clear H0;destruct r as [ |r1 r2];simpl; try rewrite spec_w_0; try rewrite spec_w_0W;repeat rewrite Zplus_0_r; intros (H1,H2) ]). @@ -611,10 +611,10 @@ Section DoubleDiv21. rewrite <- wwB_wBwB;rewrite H1. rewrite spec_w_0 in H4;rewrite Zplus_0_r in H4. repeat rewrite Zmult_plus_distr_l. rewrite <- (Zmult_assoc [|r1|]). - rewrite <- Zpower_2; rewrite <- wwB_wBwB;rewrite H4;simpl;ring. + rewrite <- Zpower_2; rewrite <- wwB_wBwB;rewrite H4;simpl;ring. split;[rewrite wwB_wBwB | split;zarith]. - replace (([|a1h|] * wB + [|a1l|]) * wB^2 + ([|a3|] * wB + [|a4|])) - with (([|a1h|] * wwB + [|a1l|] * wB + [|a3|])*wB+ [|a4|]). + replace (([|a1h|] * wB + [|a1l|]) * wB^2 + ([|a3|] * wB + [|a4|])) + with (([|a1h|] * wwB + [|a1l|] * wB + [|a3|])*wB+ [|a4|]). rewrite H1;ring. rewrite wwB_wBwB;ring. change [|a4|] with (0*wB+[|a4|]);apply beta_lex_inv;zarith. assert (1 <= wB/2);zarith. @@ -624,7 +624,7 @@ Section DoubleDiv21. intros q r H0;generalize (H0 Eq1 H3);clear H0;intros (H4,H5) end. split;trivial. replace (([|a1h|] * wB + [|a1l|]) * wwB + ([|a3|] * wB + [|a4|])) with - (([|a1h|] * wwB + [|a1l|] * wB + [|a3|])*wB + [|a4|]); + (([|a1h|] * wwB + [|a1l|] * wB + [|a3|])*wB + [|a4|]); [rewrite H1 | rewrite wwB_wBwB;ring]. replace (([|q1|]*([|b1|]*wB+[|b2|])+([|r1|]*wB+[|r2|]))*wB+[|a4|]) with (([|q1|]*([|b1|]*wB+[|b2|]))*wB+([|r1|]*wwB+[|r2|]*wB+[|a4|])); @@ -666,22 +666,22 @@ Section DoubleDivGt. Eval lazy beta iota delta [ww_sub ww_opp] in let p := w_head0 bh in match w_compare p w_0 with - | Gt => + | Gt => let b1 := w_add_mul_div p bh bl in let b2 := w_add_mul_div p bl w_0 in let a1 := w_add_mul_div p w_0 ah in let a2 := w_add_mul_div p ah al in let a3 := w_add_mul_div p al w_0 in let (q,r) := w_div32 a1 a2 a3 b1 b2 in - (WW w_0 q, ww_add_mul_div + (WW w_0 q, ww_add_mul_div (ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c w_opp w_sub w_sub_carry _ww_zdigits (w_0W p)) W0 r) | _ => (ww_1, ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c w_opp w_sub w_sub_carry (WW ah al) (WW bh bl)) end. - Definition ww_div_gt a b := - Eval lazy beta iota delta [ww_div_gt_aux double_divn1 + Definition ww_div_gt a b := + Eval lazy beta iota delta [ww_div_gt_aux double_divn1 double_divn1_p double_divn1_p_aux double_divn1_0 double_divn1_0_aux double_split double_0 double_WW] in match a, b with @@ -691,11 +691,11 @@ Section DoubleDivGt. if w_eq0 ah then let (q,r) := w_div_gt al bl in (WW w_0 q, w_0W r) - else + else match w_compare w_0 bh with - | Eq => + | Eq => let(q,r):= - double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 + double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub 1 a bl in (q, w_0W r) | Lt => ww_div_gt_aux ah al bh bl @@ -707,7 +707,7 @@ Section DoubleDivGt. Eval lazy beta iota delta [ww_sub ww_opp] in let p := w_head0 bh in match w_compare p w_0 with - | Gt => + | Gt => let b1 := w_add_mul_div p bh bl in let b2 := w_add_mul_div p bl w_0 in let a1 := w_add_mul_div p w_0 ah in @@ -716,13 +716,13 @@ Section DoubleDivGt. let (q,r) := w_div32 a1 a2 a3 b1 b2 in ww_add_mul_div (ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c w_opp w_sub w_sub_carry _ww_zdigits (w_0W p)) W0 r - | _ => + | _ => ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c w_opp w_sub w_sub_carry (WW ah al) (WW bh bl) end. - Definition ww_mod_gt a b := - Eval lazy beta iota delta [ww_mod_gt_aux double_modn1 + Definition ww_mod_gt a b := + Eval lazy beta iota delta [ww_mod_gt_aux double_modn1 double_modn1_p double_modn1_p_aux double_modn1_0 double_modn1_0_aux double_split double_0 double_WW snd] in match a, b with @@ -730,10 +730,10 @@ Section DoubleDivGt. | _, W0 => W0 | WW ah al, WW bh bl => if w_eq0 ah then w_0W (w_mod_gt al bl) - else + else match w_compare w_0 bh with - | Eq => - w_0W (double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 + | Eq => + w_0W (double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 a bl) | Lt => ww_mod_gt_aux ah al bh bl | Gt => W0 (* cas absurde *) @@ -741,14 +741,14 @@ Section DoubleDivGt. end. Definition ww_gcd_gt_body (cont: w->w->w->w->zn2z w) (ah al bh bl: w) := - Eval lazy beta iota delta [ww_mod_gt_aux double_modn1 + Eval lazy beta iota delta [ww_mod_gt_aux double_modn1 double_modn1_p double_modn1_p_aux double_modn1_0 double_modn1_0_aux double_split double_0 double_WW snd] in match w_compare w_0 bh with | Eq => match w_compare w_0 bl with | Eq => WW ah al (* normalement n'arrive pas si forme normale *) - | Lt => + | Lt => let m := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW ah al) bl in WW w_0 (w_gcd_gt bl m) @@ -757,14 +757,14 @@ Section DoubleDivGt. | Lt => let m := ww_mod_gt_aux ah al bh bl in match m with - | W0 => WW bh bl + | W0 => WW bh bl | WW mh ml => match w_compare w_0 mh with | Eq => match w_compare w_0 ml with | Eq => WW bh bl - | _ => - let r := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 + | _ => + let r := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW bh bl) ml in WW w_0 (w_gcd_gt ml r) end @@ -779,18 +779,18 @@ Section DoubleDivGt. end | Gt => W0 (* absurde *) end. - - Fixpoint ww_gcd_gt_aux - (p:positive) (cont: w -> w -> w -> w -> zn2z w) (ah al bh bl : w) + + Fixpoint ww_gcd_gt_aux + (p:positive) (cont: w -> w -> w -> w -> zn2z w) (ah al bh bl : w) {struct p} : zn2z w := - ww_gcd_gt_body + ww_gcd_gt_body (fun mh ml rh rl => match p with | xH => cont mh ml rh rl | xO p => ww_gcd_gt_aux p (ww_gcd_gt_aux p cont) mh ml rh rl | xI p => ww_gcd_gt_aux p (ww_gcd_gt_aux p cont) mh ml rh rl end) ah al bh bl. - + (* Proof *) Variable w_to_Z : w -> Z. @@ -816,7 +816,7 @@ Section DoubleDivGt. | Gt => [|x|] > [|y|] end. Variable spec_eq0 : forall x, w_eq0 x = true -> [|x|] = 0. - + Variable spec_opp_c : forall x, [-|w_opp_c x|] = -[|x|]. Variable spec_opp : forall x, [|w_opp x|] = (-[|x|]) mod wB. Variable spec_opp_carry : forall x, [|w_opp_carry x|] = wB - [|x|] - 1. @@ -854,8 +854,8 @@ Section DoubleDivGt. wB/2 <= [|b1|] -> [[WW a1 a2]] < [[WW b1 b2]] -> let (q,r) := w_div32 a1 a2 a3 b1 b2 in - [|a1|] * wwB + [|a2|] * wB + [|a3|] = - [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ + [|a1|] * wwB + [|a2|] * wB + [|a3|] = + [|q|] * ([|b1|] * wB + [|b2|]) + [[r]] /\ 0 <= [[r]] < [|b1|] * wB + [|b2|]. Variable spec_w_zdigits: [|w_zdigits|] = Zpos w_digits. @@ -899,14 +899,14 @@ Section DoubleDivGt. change (let (q, r) := let p := w_head0 bh in match w_compare p w_0 with - | Gt => + | Gt => let b1 := w_add_mul_div p bh bl in let b2 := w_add_mul_div p bl w_0 in let a1 := w_add_mul_div p w_0 ah in let a2 := w_add_mul_div p ah al in let a3 := w_add_mul_div p al w_0 in let (q,r) := w_div32 a1 a2 a3 b1 b2 in - (WW w_0 q, ww_add_mul_div + (WW w_0 q, ww_add_mul_div (ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c w_opp w_sub w_sub_carry _ww_zdigits (w_0W p)) W0 r) | _ => (ww_1, ww_sub w_0 w_WW w_opp_c w_opp_carry w_sub_c @@ -931,7 +931,7 @@ Section DoubleDivGt. case (spec_to_Z (w_head0 bh)); auto with zarith. assert ([|w_head0 bh|] < Zpos w_digits). destruct (Z_lt_ge_dec [|w_head0 bh|] (Zpos w_digits));trivial. - elimtype False. + exfalso. assert (2 ^ [|w_head0 bh|] * [|bh|] >= wB);auto with zarith. apply Zle_ge; replace wB with (wB * 1);try ring. Spec_w_to_Z bh;apply Zmult_le_compat;zarith. @@ -945,11 +945,11 @@ Section DoubleDivGt. (spec_add_mul_div bl w_0 Hb); rewrite spec_w_0; repeat rewrite Zmult_0_l;repeat rewrite Zplus_0_l; rewrite Zdiv_0_l;repeat rewrite Zplus_0_r. - Spec_w_to_Z ah;Spec_w_to_Z bh. + Spec_w_to_Z ah;Spec_w_to_Z bh. unfold base;repeat rewrite Zmod_shift_r;zarith. assert (H3:=to_Z_div_minus_p ah HHHH);assert(H4:=to_Z_div_minus_p al HHHH); assert (H5:=to_Z_div_minus_p bl HHHH). - rewrite Zmult_comm in Hh. + rewrite Zmult_comm in Hh. assert (2^[|w_head0 bh|] < wB). unfold base;apply Zpower_lt_monotone;zarith. unfold base in H0;rewrite Zmod_small;zarith. fold wB; rewrite (Zmod_small ([|bh|] * 2 ^ [|w_head0 bh|]));zarith. @@ -964,15 +964,15 @@ Section DoubleDivGt. (w_add_mul_div (w_head0 bh) al w_0) (w_add_mul_div (w_head0 bh) bh bl) (w_add_mul_div (w_head0 bh) bl w_0)) as (q,r). - rewrite V1;rewrite V2. rewrite Zmult_plus_distr_l. - rewrite <- (Zplus_assoc ([|bh|] * 2 ^ [|w_head0 bh|] * wB)). + rewrite V1;rewrite V2. rewrite Zmult_plus_distr_l. + rewrite <- (Zplus_assoc ([|bh|] * 2 ^ [|w_head0 bh|] * wB)). unfold base;rewrite <- shift_unshift_mod;zarith. fold wB. replace ([|bh|] * 2 ^ [|w_head0 bh|] * wB + [|bl|] * 2 ^ [|w_head0 bh|]) with ([[WW bh bl]] * 2^[|w_head0 bh|]). 2:simpl;ring. fold wwB. rewrite wwB_wBwB. rewrite Zpower_2. rewrite U1;rewrite U2;rewrite U3. - rewrite Zmult_assoc. rewrite Zmult_plus_distr_l. + rewrite Zmult_assoc. rewrite Zmult_plus_distr_l. rewrite (Zplus_assoc ([|ah|] / 2^(Zpos(w_digits) - [|w_head0 bh|])*wB * wB)). - rewrite <- Zmult_plus_distr_l. rewrite <- Zplus_assoc. + rewrite <- Zmult_plus_distr_l. rewrite <- Zplus_assoc. unfold base;repeat rewrite <- shift_unshift_mod;zarith. fold wB. replace ([|ah|] * 2 ^ [|w_head0 bh|] * wB + [|al|] * 2 ^ [|w_head0 bh|]) with ([[WW ah al]] * 2^[|w_head0 bh|]). 2:simpl;ring. @@ -1027,7 +1027,7 @@ Section DoubleDivGt. [[a]] = [[q]] * [[b]] + [[r]] /\ 0 <= [[r]] < [[b]]. Proof. - intros a b Hgt Hpos;unfold ww_div_gt. + intros a b Hgt Hpos;unfold ww_div_gt. change (let (q,r) := match a, b with | W0, _ => (W0,W0) | _, W0 => (W0,W0) @@ -1035,23 +1035,23 @@ Section DoubleDivGt. if w_eq0 ah then let (q,r) := w_div_gt al bl in (WW w_0 q, w_0W r) - else + else match w_compare w_0 bh with - | Eq => + | Eq => let(q,r):= - double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 + double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub 1 a bl in (q, w_0W r) | Lt => ww_div_gt_aux ah al bh bl | Gt => (W0,W0) (* cas absurde *) end - end in [[a]] = [[q]] * [[b]] + [[r]] /\ 0 <= [[r]] < [[b]]). + end in [[a]] = [[q]] * [[b]] + [[r]] /\ 0 <= [[r]] < [[b]]). destruct a as [ |ah al]. simpl in Hgt;omega. destruct b as [ |bh bl]. simpl in Hpos;omega. Spec_w_to_Z ah; Spec_w_to_Z al; Spec_w_to_Z bh; Spec_w_to_Z bl. assert (H:=@spec_eq0 ah);destruct (w_eq0 ah). simpl ww_to_Z;rewrite H;trivial. simpl in Hgt;rewrite H in Hgt;trivial. - assert ([|bh|] <= 0). + assert ([|bh|] <= 0). apply beta_lex with (d:=[|al|])(b:=[|bl|]) (beta := wB);zarith. assert ([|bh|] = 0);zarith. rewrite H1 in Hgt;rewrite H1;simpl in Hgt. simpl. simpl in Hpos;rewrite H1 in Hpos;simpl in Hpos. @@ -1066,12 +1066,12 @@ Section DoubleDivGt. w_div21 w_compare w_sub w_to_Z spec_to_Z spec_w_zdigits spec_w_0 spec_w_WW spec_head0 spec_add_mul_div spec_div21 spec_compare spec_sub 1 (WW ah al) bl Hpos). unfold double_to_Z,double_wB,double_digits in H2. - destruct (double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 + destruct (double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW ah al) bl). rewrite spec_w_0W;unfold ww_to_Z;trivial. apply spec_ww_div_gt_aux;trivial. rewrite spec_w_0 in Hcmp;trivial. - rewrite spec_w_0 in Hcmp;elimtype False;omega. + rewrite spec_w_0 in Hcmp;exfalso;omega. Qed. Lemma spec_ww_mod_gt_aux_eq : forall ah al bh bl, @@ -1104,26 +1104,26 @@ Section DoubleDivGt. rewrite Zmult_comm in H;destruct H. symmetry;apply Zmod_unique with [|q|];trivial. Qed. - + Lemma spec_ww_mod_gt_eq : forall a b, [[a]] > [[b]] -> 0 < [[b]] -> [[ww_mod_gt a b]] = [[snd (ww_div_gt a b)]]. Proof. intros a b Hgt Hpos. - change (ww_mod_gt a b) with + change (ww_mod_gt a b) with (match a, b with | W0, _ => W0 | _, W0 => W0 | WW ah al, WW bh bl => if w_eq0 ah then w_0W (w_mod_gt al bl) - else + else match w_compare w_0 bh with - | Eq => - w_0W (double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 + | Eq => + w_0W (double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 a bl) | Lt => ww_mod_gt_aux ah al bh bl | Gt => W0 (* cas absurde *) end end). - change (ww_div_gt a b) with + change (ww_div_gt a b) with (match a, b with | W0, _ => (W0,W0) | _, W0 => (W0,W0) @@ -1131,11 +1131,11 @@ Section DoubleDivGt. if w_eq0 ah then let (q,r) := w_div_gt al bl in (WW w_0 q, w_0W r) - else + else match w_compare w_0 bh with - | Eq => + | Eq => let(q,r):= - double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 + double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub 1 a bl in (q, w_0W r) | Lt => ww_div_gt_aux ah al bh bl @@ -1147,7 +1147,7 @@ Section DoubleDivGt. Spec_w_to_Z ah; Spec_w_to_Z al; Spec_w_to_Z bh; Spec_w_to_Z bl. assert (H:=@spec_eq0 ah);destruct (w_eq0 ah). simpl in Hgt;rewrite H in Hgt;trivial. - assert ([|bh|] <= 0). + assert ([|bh|] <= 0). apply beta_lex with (d:=[|al|])(b:=[|bl|]) (beta := wB);zarith. assert ([|bh|] = 0);zarith. rewrite H1 in Hgt;simpl in Hgt. simpl in Hpos;rewrite H1 in Hpos;simpl in Hpos. @@ -1155,7 +1155,7 @@ Section DoubleDivGt. destruct (w_div_gt al bl);simpl;rewrite spec_w_0W;trivial. clear H. assert (H2 := spec_compare w_0 bh);destruct (w_compare w_0 bh). - rewrite (@spec_double_modn1_aux w w_zdigits w_0 w_WW w_head0 w_add_mul_div + rewrite (@spec_double_modn1_aux w w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub w_to_Z spec_w_0 spec_compare 1 (WW ah al) bl). destruct (double_divn1 w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW ah al) bl);simpl;trivial. @@ -1174,7 +1174,7 @@ Section DoubleDivGt. rewrite Zmult_comm;trivial. Qed. - Lemma Zis_gcd_mod : forall a b d, + Lemma Zis_gcd_mod : forall a b d, 0 < b -> Zis_gcd b (a mod b) d -> Zis_gcd a b d. Proof. intros a b d H H1; apply Zis_gcd_for_euclid with (a/b). @@ -1182,12 +1182,12 @@ Section DoubleDivGt. ring_simplify (b * (a / b) + a mod b - a / b * b);trivial. zarith. Qed. - Lemma spec_ww_gcd_gt_aux_body : + Lemma spec_ww_gcd_gt_aux_body : forall ah al bh bl n cont, - [[WW bh bl]] <= 2^n -> + [[WW bh bl]] <= 2^n -> [[WW ah al]] > [[WW bh bl]] -> - (forall xh xl yh yl, - [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 2^(n-1) -> + (forall xh xl yh yl, + [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 2^(n-1) -> Zis_gcd [[WW xh xl]] [[WW yh yl]] [[cont xh xl yh yl]]) -> Zis_gcd [[WW ah al]] [[WW bh bl]] [[ww_gcd_gt_body cont ah al bh bl]]. Proof. @@ -1196,7 +1196,7 @@ Section DoubleDivGt. | Eq => match w_compare w_0 bl with | Eq => WW ah al (* normalement n'arrive pas si forme normale *) - | Lt => + | Lt => let m := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW ah al) bl in WW w_0 (w_gcd_gt bl m) @@ -1205,14 +1205,14 @@ Section DoubleDivGt. | Lt => let m := ww_mod_gt_aux ah al bh bl in match m with - | W0 => WW bh bl + | W0 => WW bh bl | WW mh ml => match w_compare w_0 mh with | Eq => match w_compare w_0 ml with | Eq => WW bh bl - | _ => - let r := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 + | _ => + let r := double_modn1 w_zdigits w_0 w_head0 w_add_mul_div w_div21 w_compare w_sub 1 (WW bh bl) ml in WW w_0 (w_gcd_gt ml r) end @@ -1227,10 +1227,10 @@ Section DoubleDivGt. end | Gt => W0 (* absurde *) end). - assert (Hbh := spec_compare w_0 bh);destruct (w_compare w_0 bh). + assert (Hbh := spec_compare w_0 bh);destruct (w_compare w_0 bh). simpl ww_to_Z in *. rewrite spec_w_0 in Hbh;rewrite <- Hbh; rewrite Zmult_0_l;rewrite Zplus_0_l. - assert (Hbl := spec_compare w_0 bl); destruct (w_compare w_0 bl). + assert (Hbl := spec_compare w_0 bl); destruct (w_compare w_0 bl). rewrite spec_w_0 in Hbl;rewrite <- Hbl;apply Zis_gcd_0. simpl;rewrite spec_w_0;rewrite Zmult_0_l;rewrite Zplus_0_l. rewrite spec_w_0 in Hbl. @@ -1239,54 +1239,54 @@ Section DoubleDivGt. rewrite <- (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub w_to_Z spec_to_Z spec_w_zdigits spec_w_0 spec_w_WW spec_head0 spec_add_mul_div spec_div21 spec_compare spec_sub 1 (WW ah al) bl Hbl). - apply spec_gcd_gt. - rewrite (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW); trivial. - apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => + apply spec_gcd_gt. + rewrite (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW); trivial. + apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => destruct (Z_mod_lt x y);zarith end. - rewrite spec_w_0 in Hbl;Spec_w_to_Z bl;elimtype False;omega. + rewrite spec_w_0 in Hbl;Spec_w_to_Z bl;exfalso;omega. rewrite spec_w_0 in Hbh;assert (H:= spec_ww_mod_gt_aux _ _ _ Hgt Hbh). - assert (H2 : 0 < [[WW bh bl]]). + assert (H2 : 0 < [[WW bh bl]]). simpl;Spec_w_to_Z bl. apply Zlt_le_trans with ([|bh|]*wB);zarith. apply Zmult_lt_0_compat;zarith. apply Zis_gcd_mod;trivial. rewrite <- H. simpl in *;destruct (ww_mod_gt_aux ah al bh bl) as [ |mh ml]. - simpl;apply Zis_gcd_0;zarith. - assert (Hmh := spec_compare w_0 mh);destruct (w_compare w_0 mh). + simpl;apply Zis_gcd_0;zarith. + assert (Hmh := spec_compare w_0 mh);destruct (w_compare w_0 mh). simpl;rewrite spec_w_0 in Hmh; rewrite <- Hmh;simpl. - assert (Hml := spec_compare w_0 ml);destruct (w_compare w_0 ml). + assert (Hml := spec_compare w_0 ml);destruct (w_compare w_0 ml). rewrite <- Hml;rewrite spec_w_0;simpl;apply Zis_gcd_0. - simpl;rewrite spec_w_0;simpl. + simpl;rewrite spec_w_0;simpl. rewrite spec_w_0 in Hml. apply Zis_gcd_mod;zarith. change ([|bh|] * wB + [|bl|]) with (double_to_Z w_digits w_to_Z 1 (WW bh bl)). rewrite <- (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW w_head0 w_add_mul_div w_div21 w_compare w_sub w_to_Z spec_to_Z spec_w_zdigits spec_w_0 spec_w_WW spec_head0 spec_add_mul_div spec_div21 spec_compare spec_sub 1 (WW bh bl) ml Hml). - apply spec_gcd_gt. - rewrite (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW); trivial. - apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => + apply spec_gcd_gt. + rewrite (@spec_double_modn1 w w_digits w_zdigits w_0 w_WW); trivial. + apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => destruct (Z_mod_lt x y);zarith end. - rewrite spec_w_0 in Hml;Spec_w_to_Z ml;elimtype False;omega. + rewrite spec_w_0 in Hml;Spec_w_to_Z ml;exfalso;omega. rewrite spec_w_0 in Hmh. assert ([[WW bh bl]] > [[WW mh ml]]). - rewrite H;simpl; apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => + rewrite H;simpl; apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => destruct (Z_mod_lt x y);zarith end. assert (H1:= spec_ww_mod_gt_aux _ _ _ H0 Hmh). - assert (H3 : 0 < [[WW mh ml]]). + assert (H3 : 0 < [[WW mh ml]]). simpl;Spec_w_to_Z ml. apply Zlt_le_trans with ([|mh|]*wB);zarith. apply Zmult_lt_0_compat;zarith. apply Zis_gcd_mod;zarith. simpl in *;rewrite <- H1. destruct (ww_mod_gt_aux bh bl mh ml) as [ |rh rl]. simpl; apply Zis_gcd_0. simpl;apply Hcont. simpl in H1;rewrite H1. - apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => + apply Zlt_gt;match goal with | |- ?x mod ?y < ?y => destruct (Z_mod_lt x y);zarith end. - apply Zle_trans with (2^n/2). - apply Zdiv_le_lower_bound;zarith. + apply Zle_trans with (2^n/2). + apply Zdiv_le_lower_bound;zarith. apply Zle_trans with ([|bh|] * wB + [|bl|]);zarith. assert (H3' := Z_div_mod_eq [[WW bh bl]] [[WW mh ml]] (Zlt_gt _ _ H3)). assert (H4' : 0 <= [[WW bh bl]]/[[WW mh ml]]). apply Zge_le;apply Z_div_ge0;zarith. simpl in *;rewrite H1. pattern ([|bh|] * wB + [|bl|]) at 2;rewrite H3'. destruct (Zle_lt_or_eq _ _ H4'). - assert (H6' : [[WW bh bl]] mod [[WW mh ml]] = + assert (H6' : [[WW bh bl]] mod [[WW mh ml]] = [[WW bh bl]] - [[WW mh ml]] * ([[WW bh bl]]/[[WW mh ml]])). simpl;pattern ([|bh|] * wB + [|bl|]) at 2;rewrite H3';ring. simpl in H6'. assert ([[WW mh ml]] <= [[WW mh ml]] * ([[WW bh bl]]/[[WW mh ml]])). @@ -1300,14 +1300,14 @@ Section DoubleDivGt. rewrite Z_div_mult;zarith. assert (2^1 <= 2^n). change (2^1) with 2;zarith. assert (H7 := @Zpower_le_monotone_inv 2 1 n);zarith. - rewrite spec_w_0 in Hmh;Spec_w_to_Z mh;elimtype False;zarith. - rewrite spec_w_0 in Hbh;Spec_w_to_Z bh;elimtype False;zarith. + rewrite spec_w_0 in Hmh;Spec_w_to_Z mh;exfalso;zarith. + rewrite spec_w_0 in Hbh;Spec_w_to_Z bh;exfalso;zarith. Qed. - Lemma spec_ww_gcd_gt_aux : + Lemma spec_ww_gcd_gt_aux : forall p cont n, - (forall xh xl yh yl, - [[WW xh xl]] > [[WW yh yl]] -> + (forall xh xl yh yl, + [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 2^n -> Zis_gcd [[WW xh xl]] [[WW yh yl]] [[cont xh xl yh yl]]) -> forall ah al bh bl , [[WW ah al]] > [[WW bh bl]] -> @@ -1334,7 +1334,7 @@ Section DoubleDivGt. apply Zle_trans with (2 ^ (Zpos p + n -1));zarith. apply Zpower_le_monotone2;zarith. apply Zle_trans with (2 ^ (2*Zpos p + n -1));zarith. - apply Zpower_le_monotone2;zarith. + apply Zpower_le_monotone2;zarith. apply spec_ww_gcd_gt_aux_body with (n := n+1);trivial. rewrite Zplus_comm;trivial. ring_simplify (n + 1 - 1);trivial. @@ -1352,16 +1352,16 @@ Section DoubleDiv. Variable ww_div_gt : zn2z w -> zn2z w -> zn2z w * zn2z w. Variable ww_mod_gt : zn2z w -> zn2z w -> zn2z w. - Definition ww_div a b := - match ww_compare a b with - | Gt => ww_div_gt a b + Definition ww_div a b := + match ww_compare a b with + | Gt => ww_div_gt a b | Eq => (ww_1, W0) | Lt => (W0, a) end. - Definition ww_mod a b := - match ww_compare a b with - | Gt => ww_mod_gt a b + Definition ww_mod a b := + match ww_compare a b with + | Gt => ww_mod_gt a b | Eq => W0 | Lt => a end. @@ -1401,7 +1401,7 @@ Section DoubleDiv. Proof. intros a b Hpos;unfold ww_div. assert (H:=spec_ww_compare a b);destruct (ww_compare a b). - simpl;rewrite spec_ww_1;split;zarith. + simpl;rewrite spec_ww_1;split;zarith. simpl;split;[ring|Spec_ww_to_Z a;zarith]. apply spec_ww_div_gt;trivial. Qed. @@ -1409,7 +1409,7 @@ Section DoubleDiv. Lemma spec_ww_mod : forall a b, 0 < [[b]] -> [[ww_mod a b]] = [[a]] mod [[b]]. Proof. - intros a b Hpos;unfold ww_mod. + intros a b Hpos;unfold ww_mod. assert (H := spec_ww_compare a b);destruct (ww_compare a b). simpl;apply Zmod_unique with 1;try rewrite H;zarith. Spec_ww_to_Z a;symmetry;apply Zmod_small;zarith. @@ -1424,8 +1424,8 @@ Section DoubleDiv. Variable w_gcd_gt : w -> w -> w. Variable _ww_digits : positive. Variable spec_ww_digits_ : _ww_digits = xO w_digits. - Variable ww_gcd_gt_fix : - positive -> (w -> w -> w -> w -> zn2z w) -> + Variable ww_gcd_gt_fix : + positive -> (w -> w -> w -> w -> zn2z w) -> w -> w -> w -> w -> zn2z w. Variable spec_w_0 : [|w_0|] = 0. @@ -1440,10 +1440,10 @@ Section DoubleDiv. Variable spec_eq0 : forall x, w_eq0 x = true -> [|x|] = 0. Variable spec_gcd_gt : forall a b, [|a|] > [|b|] -> Zis_gcd [|a|] [|b|] [|w_gcd_gt a b|]. - Variable spec_gcd_gt_fix : + Variable spec_gcd_gt_fix : forall p cont n, - (forall xh xl yh yl, - [[WW xh xl]] > [[WW yh yl]] -> + (forall xh xl yh yl, + [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 2^n -> Zis_gcd [[WW xh xl]] [[WW yh yl]] [[cont xh xl yh yl]]) -> forall ah al bh bl , [[WW ah al]] > [[WW bh bl]] -> @@ -1451,20 +1451,20 @@ Section DoubleDiv. Zis_gcd [[WW ah al]] [[WW bh bl]] [[ww_gcd_gt_fix p cont ah al bh bl]]. - Definition gcd_cont (xh xl yh yl:w) := + Definition gcd_cont (xh xl yh yl:w) := match w_compare w_1 yl with - | Eq => ww_1 + | Eq => ww_1 | _ => WW xh xl end. - Lemma spec_gcd_cont : forall xh xl yh yl, - [[WW xh xl]] > [[WW yh yl]] -> + Lemma spec_gcd_cont : forall xh xl yh yl, + [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 1 -> Zis_gcd [[WW xh xl]] [[WW yh yl]] [[gcd_cont xh xl yh yl]]. Proof. intros xh xl yh yl Hgt' Hle. simpl in Hle. assert ([|yh|] = 0). - change 1 with (0*wB+1) in Hle. + change 1 with (0*wB+1) in Hle. assert (0 <= 1 < wB). split;zarith. apply wB_pos. assert (H1:= beta_lex _ _ _ _ _ Hle (spec_to_Z yl) H). Spec_w_to_Z yh;zarith. @@ -1473,20 +1473,20 @@ Section DoubleDiv. simpl;rewrite H;simpl;destruct (w_compare w_1 yl). rewrite spec_ww_1;rewrite <- Hcmpy;apply Zis_gcd_mod;zarith. rewrite <- (Zmod_unique ([|xh|]*wB+[|xl|]) 1 ([|xh|]*wB+[|xl|]) 0);zarith. - rewrite H in Hle; elimtype False;zarith. + rewrite H in Hle; exfalso;zarith. assert ([|yl|] = 0). Spec_w_to_Z yl;zarith. rewrite H0;simpl;apply Zis_gcd_0;trivial. Qed. - + Variable cont : w -> w -> w -> w -> zn2z w. - Variable spec_cont : forall xh xl yh yl, - [[WW xh xl]] > [[WW yh yl]] -> + Variable spec_cont : forall xh xl yh yl, + [[WW xh xl]] > [[WW yh yl]] -> [[WW yh yl]] <= 1 -> Zis_gcd [[WW xh xl]] [[WW yh yl]] [[cont xh xl yh yl]]. - - Definition ww_gcd_gt a b := - match a, b with + + Definition ww_gcd_gt a b := + match a, b with | W0, _ => b | _, W0 => a | WW ah al, WW bh bl => @@ -1509,8 +1509,8 @@ Section DoubleDiv. destruct a as [ |ah al]. simpl;apply Zis_gcd_sym;apply Zis_gcd_0. destruct b as [ |bh bl]. simpl;apply Zis_gcd_0. simpl in Hgt. generalize (@spec_eq0 ah);destruct (w_eq0 ah);intros. - simpl;rewrite H in Hgt;trivial;rewrite H;trivial;rewrite spec_w_0;simpl. - assert ([|bh|] <= 0). + simpl;rewrite H in Hgt;trivial;rewrite H;trivial;rewrite spec_w_0;simpl. + assert ([|bh|] <= 0). apply beta_lex with (d:=[|al|])(b:=[|bl|]) (beta := wB);zarith. Spec_w_to_Z bh;assert ([|bh|] = 0);zarith. rewrite H1 in Hgt;simpl in Hgt. rewrite H1;simpl;auto. clear H. @@ -1522,7 +1522,7 @@ Section DoubleDiv. Lemma spec_ww_gcd : forall a b, Zis_gcd [[a]] [[b]] [[ww_gcd a b]]. Proof. intros a b. - change (ww_gcd a b) with + change (ww_gcd a b) with (match ww_compare a b with | Gt => ww_gcd_gt a b | Eq => a |