summaryrefslogtreecommitdiff
path: root/arm/eabi/Conventions1.v
diff options
context:
space:
mode:
Diffstat (limited to 'arm/eabi/Conventions1.v')
-rw-r--r--arm/eabi/Conventions1.v509
1 files changed, 0 insertions, 509 deletions
diff --git a/arm/eabi/Conventions1.v b/arm/eabi/Conventions1.v
deleted file mode 100644
index c26d29e..0000000
--- a/arm/eabi/Conventions1.v
+++ /dev/null
@@ -1,509 +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 Events.
-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 application binary interface (ABI) in our choice
- of callee- and caller-save registers.
-*)
-
-Definition int_caller_save_regs :=
- R0 :: R1 :: R2 :: R3 :: R12 :: nil.
-
-Definition float_caller_save_regs :=
- F0 :: F1 :: F2 :: F3 :: F4 :: F5 :: F6 :: F7 :: nil.
-
-Definition int_callee_save_regs :=
- R4 :: R5 :: R6 :: R7 :: R8 :: R9 :: R10 :: R11 :: nil.
-
-Definition float_callee_save_regs :=
- F8 :: F9 :: F10 :: F11 :: F12 :: F13 :: F14 :: F15 :: nil.
-
-Definition destroyed_at_call :=
- int_caller_save_regs ++ float_caller_save_regs.
-
-Definition dummy_int_reg := R0. (**r Used in [Coloring]. *)
-Definition dummy_float_reg := F0. (**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
- | R4 => 0 | R5 => 1 | R6 => 2 | R7 => 3
- | R8 => 4 | R9 => 5 | R10 => 6 | R11 => 7
- | _ => -1
- end.
-
-Definition index_float_callee_save (r: mreg) :=
- match r with
- | F8 => 0 | F9 => 1 | F10 => 2 | F11 => 3
- | F12 => 4 | F13 => 5 | F14 => 6 | F15 => 7
- | _ => -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 destroyed_at_call \/ In r int_callee_save_regs \/ In r float_callee_save_regs.
-Proof.
- destruct r;
- try (left; simpl; OrEq);
- try (right; left; simpl; OrEq);
- try (right; right; simpl; OrEq).
-Qed.
-
-
-Lemma int_callee_save_not_destroyed:
- forall r,
- In r destroyed_at_call -> In r int_callee_save_regs -> False.
-Proof.
- intros. revert H0 H. simpl. ElimOrEq; NotOrEq.
-Qed.
-
-Lemma float_callee_save_not_destroyed:
- forall r,
- In r destroyed_at_call -> In r float_callee_save_regs -> False.
-Proof.
- intros. revert H0 H. simpl. ElimOrEq; NotOrEq.
-Qed.
-
-Lemma int_callee_save_type:
- forall r, In r int_callee_save_regs -> mreg_type r = Tany32.
-Proof.
- intro. simpl; ElimOrEq; reflexivity.
-Qed.
-
-Lemma float_callee_save_type:
- forall r, In r float_callee_save_regs -> mreg_type r = Tany64.
-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. *)
-
-(** ** Location of function result *)
-
-(** The result value of a function is passed back to the caller in
- registers [R0] or [F0] or [R0,R1], 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) : list mreg :=
- match s.(sig_res) with
- | None => R0 :: nil
- | Some (Tint | Tany32) => R0 :: nil
- | Some (Tfloat | Tsingle | Tany64) => F0 :: nil
- | Some Tlong => R1 :: R0 :: nil
- end.
-
-(** The result registers have types compatible with that given in the signature. *)
-
-Lemma loc_result_type:
- forall sig,
- subtype_list (proj_sig_res' sig) (map mreg_type (loc_result sig)) = true.
-Proof.
- intros. unfold proj_sig_res', loc_result. destruct (sig_res sig) as [[]|]; auto.
-Qed.
-
-(** The result locations are caller-save registers *)
-
-Lemma loc_result_caller_save:
- forall (s: signature) (r: mreg),
- In r (loc_result s) -> In r destroyed_at_call.
-Proof.
- intros.
- assert (r = R0 \/ r = R1 \/ r = F0).
- unfold loc_result in H. destruct (sig_res s); [destruct t|idtac]; simpl in H; intuition.
- destruct H0 as [A | [A | A]]; subst r; simpl; OrEq.
-Qed.
-
-(** ** Location of function arguments *)
-
-(** We use the following calling conventions, adapted from the ARM EABI:
-- The first 4 integer arguments are passed in registers [R0] to [R3].
-- The first 2 double float arguments are passed in registers [F0] and [F2].
-- The first 4 single float arguments are passed in registers [F0] to [F3].
-- The first 2 long integer arguments are passed in an aligned pair of
- two integer registers.
-- Each double argument passed in a float register ``consumes'' an aligned pair
- of two integer registers.
-- Each single argument passed in a float register ``consumes'' an integer
- register.
-- Extra arguments are passed on the stack, in [Outgoing] slots, consecutively
- assigned (1 word for an integer or single argument, 2 words for a double
- or a long), starting at word offset 0.
-
-This convention is not quite that of the ARM EABI, whereas every float
-argument are passed in one or two integer registers. Unfortunately,
-this does not fit the data model of CompCert. In [PrintAsm.ml]
-we insert additional code around function calls and returns that moves
-data appropriately. *)
-
-Definition ireg_param (n: Z) : mreg :=
- if zeq n (-4) then R0
- else if zeq n (-3) then R1
- else if zeq n (-2) then R2
- else R3.
-
-Definition freg_param (n: Z) : mreg :=
- if zeq n (-4) then F0 else F2.
-
-Definition sreg_param (n: Z) : mreg :=
- if zeq n (-4) then F0
- else if zeq n (-3) then F1
- else if zeq n (-2) then F2
- else F3.
-
-Fixpoint loc_arguments_rec (tyl: list typ) (ofs: Z) {struct tyl} : list loc :=
- match tyl with
- | nil => nil
- | (Tint | Tany32) as ty :: tys =>
- (if zle 0 ofs then S Outgoing ofs ty else R (ireg_param ofs))
- :: loc_arguments_rec tys (ofs + 1)
- | (Tfloat | Tany64) as ty :: tys =>
- let ofs := align ofs 2 in
- (if zle 0 ofs then S Outgoing ofs ty else R (freg_param ofs))
- :: loc_arguments_rec tys (ofs + 2)
- | Tsingle :: tys =>
- (if zle 0 ofs then S Outgoing ofs Tsingle else R (sreg_param ofs))
- :: loc_arguments_rec tys (ofs + 1)
- | Tlong :: tys =>
- let ofs := align ofs 2 in
- (if zle 0 ofs then S Outgoing (ofs + 1) Tint else R (ireg_param (ofs + 1)))
- :: (if zle 0 ofs then S Outgoing ofs Tint else R (ireg_param ofs))
- :: loc_arguments_rec tys (ofs + 2)
- end.
-
-(** [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) (-4).
-
-(** [size_arguments s] returns the number of [Outgoing] slots used
- to call a function with signature [s]. *)
-
-Fixpoint size_arguments_rec (tyl: list typ) (ofs: Z) {struct tyl} : Z :=
- match tyl with
- | nil => ofs
- | (Tint | Tsingle | Tany32) :: tys => size_arguments_rec tys (ofs + 1)
- | (Tfloat | Tlong | Tany64) :: tys => size_arguments_rec tys (align ofs 2 + 2)
- end.
-
-Definition size_arguments (s: signature) : Z :=
- Zmax 0 (size_arguments_rec s.(sig_args) (-4)).
-
-(** 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 r destroyed_at_call
- | S Outgoing ofs ty => ofs >= 0 /\ ty <> Tlong
- | _ => False
- end.
-
-Remark ireg_param_caller_save:
- forall n, In (ireg_param n) destroyed_at_call.
-Proof.
- unfold ireg_param; intros.
- destruct (zeq n (-4)). simpl; auto.
- destruct (zeq n (-3)). simpl; auto.
- destruct (zeq n (-2)); simpl; auto.
-Qed.
-
-Remark freg_param_caller_save:
- forall n, In (freg_param n) destroyed_at_call.
-Proof.
- unfold freg_param; intros. destruct (zeq n (-4)); simpl; OrEq.
-Qed.
-
-Remark sreg_param_caller_save:
- forall n, In (sreg_param n) destroyed_at_call.
-Proof.
- unfold sreg_param; intros.
- destruct (zeq n (-4)). simpl; tauto.
- destruct (zeq n (-3)). simpl; tauto.
- destruct (zeq n (-2)); simpl; tauto.
-Qed.
-
-Remark loc_arguments_rec_charact:
- forall tyl ofs l,
- In l (loc_arguments_rec tyl ofs) ->
- match l with
- | R r => In r destroyed_at_call
- | S Outgoing ofs' ty => ofs' >= 0 /\ ofs <= ofs' /\ ty <> Tlong
- | S _ _ _ => False
- end.
-Proof.
- induction tyl; simpl loc_arguments_rec; intros.
- elim H.
- destruct a.
-- (* Tint *)
- destruct H.
- subst l. destruct (zle 0 ofs).
- split. omega. split. omega. congruence.
- apply ireg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-- (* Tfloat *)
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- destruct H.
- subst l. destruct (zle 0 (align ofs 2)).
- split. omega. split. auto. congruence.
- apply freg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-- (* Tlong *)
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- destruct H.
- subst l. destruct (zle 0 (align ofs 2)).
- split. omega. split. omega. congruence.
- apply ireg_param_caller_save.
- destruct H.
- subst l. destruct (zle 0 (align ofs 2)).
- split. omega. split. omega. congruence.
- apply ireg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-- (* Tsingle *)
- destruct H.
- subst l. destruct (zle 0 ofs).
- split. omega. split. omega. congruence.
- apply sreg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-- (* Tany32 *)
- destruct H.
- subst l. destruct (zle 0 ofs).
- split. omega. split. omega. congruence.
- apply ireg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-- (* Tany64 *)
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- destruct H.
- subst l. destruct (zle 0 (align ofs 2)).
- split. omega. split. auto. congruence.
- apply freg_param_caller_save.
- exploit IHtyl; eauto. destruct l; auto. destruct sl; auto. intuition omega.
-Qed.
-
-Lemma loc_arguments_acceptable:
- forall (s: signature) (r: loc),
- In r (loc_arguments s) -> loc_argument_acceptable r.
-Proof.
- unfold loc_arguments, loc_argument_acceptable; intros.
- generalize (loc_arguments_rec_charact _ _ _ H).
- destruct r; auto.
- destruct sl; auto.
- tauto.
-Qed.
-Hint Resolve loc_arguments_acceptable: locs.
-
-(** The offsets of [Outgoing] arguments are below [size_arguments s]. *)
-
-Remark size_arguments_rec_above:
- forall tyl ofs,
- ofs <= size_arguments_rec tyl ofs.
-Proof.
- induction tyl; simpl; intros.
- omega.
- destruct a.
- apply Zle_trans with (ofs + 1); auto; omega.
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- apply Zle_trans with (align ofs 2 + 2); auto; omega.
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- apply Zle_trans with (align ofs 2 + 2); auto; omega.
- apply Zle_trans with (ofs + 1); auto; omega.
- apply Zle_trans with (ofs + 1); auto; omega.
- assert (ofs <= align ofs 2) by (apply align_le; omega).
- apply Zle_trans with (align ofs 2 + 2); auto; omega.
-Qed.
-
-Lemma size_arguments_above:
- forall s, size_arguments s >= 0.
-Proof.
- intros; unfold size_arguments. apply Zle_ge. apply Zmax1.
-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 ofs0,
- 0 <= ofs0 ->
- ofs0 <= Zmax 0 (size_arguments_rec tyl ofs0)).
- {
- intros. generalize (size_arguments_rec_above tyl ofs0). intros.
- rewrite Zmax_spec. rewrite zlt_false. auto. omega.
- }
- assert (forall tyl ofs0,
- In (S Outgoing ofs ty) (loc_arguments_rec tyl ofs0) ->
- ofs + typesize ty <= Zmax 0 (size_arguments_rec tyl ofs0)).
- {
- induction tyl; simpl; intros.
- elim H1.
- destruct a.
- - (* Tint *)
- destruct H1; auto. destruct (zle 0 ofs0); inv H1. apply H0. omega.
- - (* Tfloat *)
- destruct H1; auto. destruct (zle 0 (align ofs0 2)); inv H1. apply H0. omega.
- - (* Tlong *)
- destruct H1.
- destruct (zle 0 (align ofs0 2)); inv H1.
- eapply Zle_trans. 2: apply H0. simpl typesize; omega. omega.
- destruct H1; auto.
- destruct (zle 0 (align ofs0 2)); inv H1.
- eapply Zle_trans. 2: apply H0. simpl typesize; omega. omega.
- - (* Tsingle *)
- destruct H1; auto. destruct (zle 0 ofs0); inv H1. apply H0. omega.
- - (* Tany32 *)
- destruct H1; auto. destruct (zle 0 ofs0); inv H1. apply H0. omega.
- - (* Tany64 *)
- destruct H1; auto. destruct (zle 0 (align ofs0 2)); inv H1. apply H0. omega.
- }
- unfold size_arguments. apply H1. auto.
-Qed.