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diff --git a/powerpc/macosx/Conventions1.v b/powerpc/macosx/Conventions1.v deleted file mode 100644 index 1ec6e88..0000000 --- a/powerpc/macosx/Conventions1.v +++ /dev/null @@ -1,599 +0,0 @@ -(* *********************************************************************) -(* *) -(* The Compcert verified compiler *) -(* *) -(* Xavier Leroy, INRIA Paris-Rocquencourt *) -(* *) -(* Copyright Institut National de Recherche en Informatique et en *) -(* Automatique. All rights reserved. This file is distributed *) -(* under the terms of the INRIA Non-Commercial License Agreement. *) -(* *) -(* *********************************************************************) - -(** Function calling conventions and other conventions regarding the use of - machine registers and stack slots. *) - -Require Import Coqlib. -Require Import AST. -Require Import Locations. - -(** * Classification of machine registers *) - -(** Machine registers (type [mreg] in module [Locations]) are divided in - the following groups: -- Temporaries used for spilling, reloading, and parallel move operations. -- Allocatable registers, that can be assigned to RTL pseudo-registers. - These are further divided into: --- Callee-save registers, whose value is preserved across a function call. --- Caller-save registers that can be modified during a function call. - - We follow the PowerPC/MacOSX application binary interface (ABI) in our choice - of callee- and caller-save registers. -*) - -Definition int_caller_save_regs := - R3 :: R4 :: R5 :: R6 :: R7 :: R8 :: R9 :: R10 :: nil. - -Definition float_caller_save_regs := - F1 :: F2 :: F3 :: F4 :: F5 :: F6 :: F7 :: F8 :: F9 :: F10 :: F11 :: nil. - -Definition int_callee_save_regs := - R14 :: R15 :: R16 :: R17 :: R18 :: R19 :: R20 :: R21 :: R22 :: - R23 :: R24 :: R25 :: R26 :: R27 :: R28 :: R29 :: R30 :: R31 :: nil. - -Definition float_callee_save_regs := - F14 :: F15 :: F16 :: F17 :: F18 :: F19 :: F20 :: F21 :: F22 :: - F23 :: F24 :: F25 :: F26 :: F27 :: F28 :: F29 :: F30 :: F31 :: nil. - -Definition destroyed_at_call_regs := - int_caller_save_regs ++ float_caller_save_regs. - -Definition destroyed_at_call := - List.map R destroyed_at_call_regs. - -Definition int_temporaries := IT1 :: IT2 :: nil. - -Definition float_temporaries := FT1 :: FT2 :: FT3 :: nil. - -Definition temporary_regs := int_temporaries ++ float_temporaries. - -Definition temporaries := List.map R temporary_regs. - -Definition destroyed_at_move_regs: list mreg := nil. - -Definition destroyed_at_move := List.map R destroyed_at_move_regs. - -Definition dummy_int_reg := R3. (**r Used in [Coloring]. *) -Definition dummy_float_reg := F1. (**r Used in [Coloring]. *) - -(** The [index_int_callee_save] and [index_float_callee_save] associate - a unique positive integer to callee-save registers. This integer is - used in [Stacking] to determine where to save these registers in - the activation record if they are used by the current function. *) - -Definition index_int_callee_save (r: mreg) := - match r with - | R14 => 0 | R15 => 1 | R16 => 2 | R17 => 3 - | R18 => 4 | R19 => 5 | R20 => 6 | R21 => 7 - | R22 => 8 | R23 => 9 | R24 => 10 | R25 => 11 - | R26 => 12 | R27 => 13 | R28 => 14 | R29 => 15 - | R30 => 16 | R31 => 17 | _ => -1 - end. - -Definition index_float_callee_save (r: mreg) := - match r with - | F14 => 0 | F15 => 1 | F16 => 2 | F17 => 3 - | F18 => 4 | F19 => 5 | F20 => 6 | F21 => 7 - | F22 => 8 | F23 => 9 | F24 => 10 | F25 => 11 - | F26 => 12 | F27 => 13 | F28 => 14 | F29 => 15 - | F30 => 16 | F31 => 17 | _ => -1 - end. - -Ltac ElimOrEq := - match goal with - | |- (?x = ?y) \/ _ -> _ => - let H := fresh in - (intro H; elim H; clear H; - [intro H; rewrite <- H; clear H | ElimOrEq]) - | |- False -> _ => - let H := fresh in (intro H; contradiction) - end. - -Ltac OrEq := - match goal with - | |- (?x = ?x) \/ _ => left; reflexivity - | |- (?x = ?y) \/ _ => right; OrEq - | |- False => fail - end. - -Ltac NotOrEq := - match goal with - | |- (?x = ?y) \/ _ -> False => - let H := fresh in ( - intro H; elim H; clear H; [intro; discriminate | NotOrEq]) - | |- False -> False => - contradiction - end. - -Lemma index_int_callee_save_pos: - forall r, In r int_callee_save_regs -> index_int_callee_save r >= 0. -Proof. - intro r. simpl; ElimOrEq; unfold index_int_callee_save; omega. -Qed. - -Lemma index_float_callee_save_pos: - forall r, In r float_callee_save_regs -> index_float_callee_save r >= 0. -Proof. - intro r. simpl; ElimOrEq; unfold index_float_callee_save; omega. -Qed. - -Lemma index_int_callee_save_pos2: - forall r, index_int_callee_save r >= 0 -> In r int_callee_save_regs. -Proof. - destruct r; simpl; intro; omegaContradiction || OrEq. -Qed. - -Lemma index_float_callee_save_pos2: - forall r, index_float_callee_save r >= 0 -> In r float_callee_save_regs. -Proof. - destruct r; simpl; intro; omegaContradiction || OrEq. -Qed. - -Lemma index_int_callee_save_inj: - forall r1 r2, - In r1 int_callee_save_regs -> - In r2 int_callee_save_regs -> - r1 <> r2 -> - index_int_callee_save r1 <> index_int_callee_save r2. -Proof. - intros r1 r2. - simpl; ElimOrEq; ElimOrEq; unfold index_int_callee_save; - intros; congruence. -Qed. - -Lemma index_float_callee_save_inj: - forall r1 r2, - In r1 float_callee_save_regs -> - In r2 float_callee_save_regs -> - r1 <> r2 -> - index_float_callee_save r1 <> index_float_callee_save r2. -Proof. - intros r1 r2. - simpl; ElimOrEq; ElimOrEq; unfold index_float_callee_save; - intros; congruence. -Qed. - -(** The following lemmas show that - (temporaries, destroyed at call, integer callee-save, float callee-save) - is a partition of the set of machine registers. *) - -Lemma int_float_callee_save_disjoint: - list_disjoint int_callee_save_regs float_callee_save_regs. -Proof. - red; intros r1 r2. simpl; ElimOrEq; ElimOrEq; discriminate. -Qed. - -Lemma register_classification: - forall r, - (In (R r) temporaries \/ In (R r) destroyed_at_call) \/ - (In r int_callee_save_regs \/ In r float_callee_save_regs). -Proof. - destruct r; - try (left; left; simpl; OrEq); - try (left; right; simpl; OrEq); - try (right; left; simpl; OrEq); - try (right; right; simpl; OrEq). -Qed. - -Lemma int_callee_save_not_destroyed: - forall r, - In (R r) temporaries \/ In (R r) destroyed_at_call -> - ~(In r int_callee_save_regs). -Proof. - intros; red; intros. elim H. - generalize H0. simpl; ElimOrEq; NotOrEq. - generalize H0. simpl; ElimOrEq; NotOrEq. -Qed. - -Lemma float_callee_save_not_destroyed: - forall r, - In (R r) temporaries \/ In (R r) destroyed_at_call -> - ~(In r float_callee_save_regs). -Proof. - intros; red; intros. elim H. - generalize H0. simpl; ElimOrEq; NotOrEq. - generalize H0. simpl; ElimOrEq; NotOrEq. -Qed. - -Lemma int_callee_save_type: - forall r, In r int_callee_save_regs -> mreg_type r = Tint. -Proof. - intro. simpl; ElimOrEq; reflexivity. -Qed. - -Lemma float_callee_save_type: - forall r, In r float_callee_save_regs -> mreg_type r = Tfloat. -Proof. - intro. simpl; ElimOrEq; reflexivity. -Qed. - -Ltac NoRepet := - match goal with - | |- list_norepet nil => - apply list_norepet_nil - | |- list_norepet (?a :: ?b) => - apply list_norepet_cons; [simpl; intuition discriminate | NoRepet] - end. - -Lemma int_callee_save_norepet: - list_norepet int_callee_save_regs. -Proof. - unfold int_callee_save_regs; NoRepet. -Qed. - -Lemma float_callee_save_norepet: - list_norepet float_callee_save_regs. -Proof. - unfold float_callee_save_regs; NoRepet. -Qed. - -(** * Function calling conventions *) - -(** The functions in this section determine the locations (machine registers - and stack slots) used to communicate arguments and results between the - caller and the callee during function calls. These locations are functions - of the signature of the function and of the call instruction. - Agreement between the caller and the callee on the locations to use - is guaranteed by our dynamic semantics for Cminor and RTL, which demand - that the signature of the call instruction is identical to that of the - called function. - - Calling conventions are largely arbitrary: they must respect the properties - proved in this section (such as no overlapping between the locations - of function arguments), but this leaves much liberty in choosing actual - locations. To ensure binary interoperability of code generated by our - compiler with libraries compiled by another PowerPC compiler, we - implement the standard conventions defined in the PowerPC/MacOS X - application binary interface. *) - -(** ** Location of function result *) - -(** The result value of a function is passed back to the caller in - registers [R3] or [F1], depending on the type of the returned value. - We treat a function without result as a function with one integer result. *) - -Definition loc_result (s: signature) : mreg := - match s.(sig_res) with - | None => R3 - | Some Tint => R3 - | Some Tfloat => F1 - end. - -(** The result location has the type stated in the signature. *) - -Lemma loc_result_type: - forall sig, - mreg_type (loc_result sig) = - match sig.(sig_res) with None => Tint | Some ty => ty end. -Proof. - intros; unfold loc_result. - destruct (sig_res sig). - destruct t; reflexivity. - reflexivity. -Qed. - -(** The result location is a caller-save register or a temporary *) - -Lemma loc_result_caller_save: - forall (s: signature), - In (R (loc_result s)) destroyed_at_call \/ In (R (loc_result s)) temporaries. -Proof. - intros; unfold loc_result. left; - destruct (sig_res s). - destruct t; simpl; OrEq. - simpl; OrEq. -Qed. - -(** ** Location of function arguments *) - -(** The PowerPC ABI states the following convention for passing arguments - to a function: -- The first 8 integer arguments are passed in registers [R3] to [R10]. -- The first 11 float arguments are passed in registers [F1] to [F11]. -- Each float argument passed in a float register ``consumes'' two - integer arguments. -- Extra arguments are passed on the stack, in [Outgoing] slots, consecutively - assigned (1 word for an integer argument, 2 words for a float), - starting at word offset 0. -- Stack space is reserved (as unused [Outgoing] slots) for the arguments - that are passed in registers. - -These conventions are somewhat baroque, but they are mandated by the ABI. -*) - -Fixpoint loc_arguments_rec - (tyl: list typ) (iregl: list mreg) (fregl: list mreg) - (ofs: Z) {struct tyl} : list loc := - match tyl with - | nil => nil - | Tint :: tys => - match iregl with - | nil => - S (Outgoing ofs Tint) :: loc_arguments_rec tys nil fregl (ofs + 1) - | ireg :: iregs => - R ireg :: loc_arguments_rec tys iregs fregl ofs - end - | Tfloat :: tys => - match fregl with - | nil => - S (Outgoing ofs Tfloat) :: loc_arguments_rec tys iregl nil (ofs + 2) - | freg :: fregs => - R freg :: loc_arguments_rec tys (list_drop 2%nat iregl) fregs ofs - end - end. - -Definition int_param_regs := - R3 :: R4 :: R5 :: R6 :: R7 :: R8 :: R9 :: R10 :: nil. -Definition float_param_regs := - F1 :: F2 :: F3 :: F4 :: F5 :: F6 :: F7 :: F8 :: F9 :: F10 :: F11 :: nil. - -(** [loc_arguments s] returns the list of locations where to store arguments - when calling a function with signature [s]. *) - -Definition loc_arguments (s: signature) : list loc := - loc_arguments_rec s.(sig_args) int_param_regs float_param_regs 8. - -(** [size_arguments s] returns the number of [Outgoing] slots used - to call a function with signature [s]. *) - -Fixpoint size_arguments_rec - (tyl: list typ) (iregl: list mreg) (fregl: list mreg) - (ofs: Z) {struct tyl} : Z := - match tyl with - | nil => ofs - | Tint :: tys => - match iregl with - | nil => size_arguments_rec tys nil fregl (ofs + 1) - | ireg :: iregs => size_arguments_rec tys iregs fregl ofs - end - | Tfloat :: tys => - match fregl with - | nil => size_arguments_rec tys iregl nil (ofs + 2) - | freg :: fregs => size_arguments_rec tys (list_drop 2%nat iregl) fregs ofs - end - end. - -Definition size_arguments (s: signature) : Z := - size_arguments_rec s.(sig_args) int_param_regs float_param_regs 8. - -(** Argument locations are either non-temporary registers or [Outgoing] - stack slots at nonnegative offsets. *) - -Definition loc_argument_acceptable (l: loc) : Prop := - match l with - | R r => ~(In l temporaries) - | S (Outgoing ofs ty) => ofs >= 0 - | _ => False - end. - -Remark loc_arguments_rec_charact: - forall tyl iregl fregl ofs l, - In l (loc_arguments_rec tyl iregl fregl ofs) -> - match l with - | R r => In r iregl \/ In r fregl - | S (Outgoing ofs' ty) => ofs' >= ofs - | S _ => False - end. -Proof. -Opaque list_drop. - induction tyl; simpl loc_arguments_rec; intros. - elim H. - destruct a. - destruct iregl; elim H; intro. - subst l. omega. - generalize (IHtyl _ _ _ _ H0). destruct l; auto. destruct s; auto. omega. - subst l. auto with coqlib. - generalize (IHtyl _ _ _ _ H0). destruct l; auto. simpl; intuition. - destruct fregl; elim H; intro. - subst l. omega. - generalize (IHtyl _ _ _ _ H0). destruct l; auto. destruct s; auto. omega. - subst l. auto with coqlib. - generalize (IHtyl _ _ _ _ H0). destruct l; auto. - intros [A|B]. left; eapply list_drop_incl; eauto. right; auto with coqlib. -Qed. - -Lemma loc_arguments_acceptable: - forall (s: signature) (r: loc), - In r (loc_arguments s) -> loc_argument_acceptable r. -Proof. - unfold loc_arguments; intros. - generalize (loc_arguments_rec_charact _ _ _ _ _ H). - destruct r. - intro H0; elim H0. simpl. unfold not. ElimOrEq; NotOrEq. - simpl. unfold not. ElimOrEq; NotOrEq. - destruct s0; try contradiction. - simpl. omega. -Qed. -Hint Resolve loc_arguments_acceptable: locs. - -(** Arguments are parwise disjoint (in the sense of [Loc.norepet]). *) - -Remark loc_arguments_rec_notin_reg: - forall tyl iregl fregl ofs r, - ~(In r iregl) -> ~(In r fregl) -> - Loc.notin (R r) (loc_arguments_rec tyl iregl fregl ofs). -Proof. - induction tyl; simpl; intros. - auto. - destruct a. - destruct iregl; simpl. auto. - simpl in H. split. apply sym_not_equal. tauto. - apply IHtyl. tauto. tauto. - destruct fregl; simpl. auto. - simpl in H0. split. apply sym_not_equal. tauto. - apply IHtyl. - red; intro. apply H. eapply list_drop_incl. eauto. - tauto. -Qed. - -Remark loc_arguments_rec_notin_local: - forall tyl iregl fregl ofs ofs0 ty0, - Loc.notin (S (Local ofs0 ty0)) (loc_arguments_rec tyl iregl fregl ofs). -Proof. - induction tyl; simpl; intros. - auto. - destruct a. - destruct iregl; simpl; auto. - destruct fregl; simpl; auto. -Qed. - -Remark loc_arguments_rec_notin_outgoing: - forall tyl iregl fregl ofs ofs0 ty0, - ofs0 + typesize ty0 <= ofs -> - Loc.notin (S (Outgoing ofs0 ty0)) (loc_arguments_rec tyl iregl fregl ofs). -Proof. - induction tyl; simpl; intros. - auto. - destruct a. - destruct iregl; simpl. - split. omega. eapply IHtyl. omega. - auto. - destruct fregl; simpl. - split. omega. eapply IHtyl. omega. - auto. -Qed. - -Lemma loc_arguments_norepet: - forall (s: signature), Loc.norepet (loc_arguments s). -Proof. - assert (forall tyl iregl fregl ofs, - list_norepet iregl -> - list_norepet fregl -> - list_disjoint iregl fregl -> - Loc.norepet (loc_arguments_rec tyl iregl fregl ofs)). - induction tyl; simpl; intros. - constructor. - destruct a. - destruct iregl; constructor. - apply loc_arguments_rec_notin_outgoing. simpl; omega. auto. - apply loc_arguments_rec_notin_reg. inversion H. auto. - apply list_disjoint_notin with (m :: iregl); auto with coqlib. - apply IHtyl. inv H; auto. auto. - eapply list_disjoint_cons_left; eauto. - destruct fregl; constructor. - apply loc_arguments_rec_notin_outgoing. simpl; omega. auto. - apply loc_arguments_rec_notin_reg. - red; intro. apply (H1 m m). eapply list_drop_incl; eauto. - auto with coqlib. auto. inv H0; auto. - apply IHtyl. eapply list_drop_norepet; eauto. - inv H0; auto. - red; intros. apply H1. eapply list_drop_incl; eauto. auto with coqlib. - - intro. unfold loc_arguments. apply H. - unfold int_param_regs. NoRepet. - unfold float_param_regs. NoRepet. - red; intros x y; simpl. ElimOrEq; ElimOrEq; discriminate. -Qed. - -(** The offsets of [Outgoing] arguments are below [size_arguments s]. *) - -Remark size_arguments_rec_above: - forall tyl iregl fregl ofs0, - ofs0 <= size_arguments_rec tyl iregl fregl ofs0. -Proof. - induction tyl; simpl; intros. - omega. - destruct a. - destruct iregl. apply Zle_trans with (ofs0 + 1); auto; omega. auto. - destruct fregl. apply Zle_trans with (ofs0 + 2); auto; omega. auto. -Qed. - -Lemma size_arguments_above: - forall s, size_arguments s >= 0. -Proof. - intros; unfold size_arguments. apply Zle_ge. apply Zle_trans with 8. omega. - apply size_arguments_rec_above. -Qed. - -Lemma loc_arguments_bounded: - forall (s: signature) (ofs: Z) (ty: typ), - In (S (Outgoing ofs ty)) (loc_arguments s) -> - ofs + typesize ty <= size_arguments s. -Proof. - intros. - assert (forall tyl iregl fregl ofs0, - In (S (Outgoing ofs ty)) (loc_arguments_rec tyl iregl fregl ofs0) -> - ofs + typesize ty <= size_arguments_rec tyl iregl fregl ofs0). - induction tyl; simpl; intros. - elim H0. - destruct a. destruct iregl; elim H0; intro. - inv H1. simpl. apply size_arguments_rec_above. auto. - discriminate. auto. - destruct fregl; elim H0; intro. - inv H1. simpl. apply size_arguments_rec_above. auto. - discriminate. auto. - unfold size_arguments. eapply H0. unfold loc_arguments in H. eauto. -Qed. - -(** Temporary registers do not overlap with argument locations. *) - -Lemma loc_arguments_not_temporaries: - forall sig, Loc.disjoint (loc_arguments sig) temporaries. -Proof. - intros; red; intros x1 x2 H. - generalize (loc_arguments_rec_charact _ _ _ _ _ H). - destruct x1. - intro H0; elim H0; simpl; (ElimOrEq; ElimOrEq; congruence). - destruct s; try contradiction. intro. - simpl; ElimOrEq; auto. -Qed. -Hint Resolve loc_arguments_not_temporaries: locs. - -(** Argument registers are caller-save. *) - -Lemma arguments_caller_save: - forall sig r, - In (R r) (loc_arguments sig) -> In (R r) destroyed_at_call. -Proof. - unfold loc_arguments; intros. - elim (loc_arguments_rec_charact _ _ _ _ _ H); simpl. - ElimOrEq; intuition. - ElimOrEq; intuition. -Qed. - -(** Argument locations agree in number with the function signature. *) - -Lemma loc_arguments_length: - forall sig, - List.length (loc_arguments sig) = List.length sig.(sig_args). -Proof. - assert (forall tyl iregl fregl ofs, - List.length (loc_arguments_rec tyl iregl fregl ofs) = List.length tyl). - induction tyl; simpl; intros. - auto. - destruct a. - destruct iregl; simpl; decEq; auto. - destruct fregl; simpl; decEq; auto. - intros. unfold loc_arguments. auto. -Qed. - -(** Argument locations agree in types with the function signature. *) - -Lemma loc_arguments_type: - forall sig, List.map Loc.type (loc_arguments sig) = sig.(sig_args). -Proof. - assert (forall tyl iregl fregl ofs, - (forall r, In r iregl -> mreg_type r = Tint) -> - (forall r, In r fregl -> mreg_type r = Tfloat) -> - List.map Loc.type (loc_arguments_rec tyl iregl fregl ofs) = tyl). - induction tyl; simpl; intros. - auto. - destruct a; [destruct iregl|destruct fregl]; simpl; - f_equal; eauto with coqlib. - apply IHtyl. intros. apply H. eapply list_drop_incl; eauto. - eauto with coqlib. - - intros. unfold loc_arguments. apply H. - intro; simpl. ElimOrEq; reflexivity. - intro; simpl. ElimOrEq; reflexivity. -Qed. |