From 600e5f3be65eeffc80d5c4cad800121fe521a1aa Mon Sep 17 00:00:00 2001 From: xleroy Date: Sat, 20 Apr 2013 15:17:40 +0000 Subject: Rename arm/linux into arm/eabi, more descriptive. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2207 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e --- arm/eabi/Conventions1.v | 453 +++++++++++++++++++++++++++++++++++++++++++++++ arm/eabi/Stacklayout.v | 132 ++++++++++++++ arm/linux/Conventions1.v | 453 ----------------------------------------------- arm/linux/Stacklayout.v | 132 -------------- 4 files changed, 585 insertions(+), 585 deletions(-) create mode 100644 arm/eabi/Conventions1.v create mode 100644 arm/eabi/Stacklayout.v delete mode 100644 arm/linux/Conventions1.v delete mode 100644 arm/linux/Stacklayout.v (limited to 'arm') diff --git a/arm/eabi/Conventions1.v b/arm/eabi/Conventions1.v new file mode 100644 index 0000000..1731eba --- /dev/null +++ b/arm/eabi/Conventions1.v @@ -0,0 +1,453 @@ +(* *********************************************************************) +(* *) +(* 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 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 = 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. *) + +(** ** 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 => R0 :: nil + | Some Tfloat => F0 :: nil + | Some Tlong => R1 :: R0 :: nil + end. + +(** The result location is a caller-save register or a temporary *) + +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 float arguments are passed in registers [F0] and [F1]. +- Each float argument passed in a float register ``consumes'' an aligned pair + of two integer registers. +- Each long integer argument is passed in an aligned pair of two integer + registers. +- Extra arguments are passed on the stack, in [Outgoing] slots, consecutively + assigned (1 word for an integer argument, 2 words for a float or a long), + starting at word offset 0. +*) + +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 F1. + +Fixpoint loc_arguments_rec (tyl: list typ) (ofs: Z) {struct tyl} : list loc := + match tyl with + | nil => nil + | Tint :: tys => + (if zle 0 ofs then S Outgoing ofs Tint else R (ireg_param ofs)) + :: loc_arguments_rec tys (ofs + 1) + | Tfloat :: tys => + let ofs := align ofs 2 in + (if zle 0 ofs then S Outgoing ofs Tfloat else R (freg_param ofs)) + :: loc_arguments_rec tys (ofs + 2) + | 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 :: tys => size_arguments_rec tys (ofs + 1) + | (Tfloat | Tlong) :: 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. + +(* +Lemma align_monotone: + forall x1 x2 y, y > 0 -> x1 <= x2 -> align x1 y <= align x2 y. +Proof. + intros. unfold align. apply Zmult_le_compat_r. apply Z_div_le. + omega. omega. omega. +Qed. +*) + +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 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. +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. +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. + } + unfold size_arguments. apply H1. auto. +Qed. diff --git a/arm/eabi/Stacklayout.v b/arm/eabi/Stacklayout.v new file mode 100644 index 0000000..7694dcf --- /dev/null +++ b/arm/eabi/Stacklayout.v @@ -0,0 +1,132 @@ +(* *********************************************************************) +(* *) +(* 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. *) +(* *) +(* *********************************************************************) + +(** Machine- and ABI-dependent layout information for activation records. *) + +Require Import Coqlib. +Require Import Bounds. + +(** The general shape of activation records is as follows, + from bottom (lowest offsets) to top: +- Space for outgoing arguments to function calls. +- Local stack slots. +- Saved values of integer callee-save registers used by the function. +- Saved values of float callee-save registers used by the function. +- Saved return address into caller. +- Pointer to activation record of the caller. +- Space for the stack-allocated data declared in Cminor. + +The [frame_env] compilation environment records the positions of +the boundaries between areas in the frame part. +*) + +Definition fe_ofs_arg := 0. + +Record frame_env : Type := mk_frame_env { + fe_size: Z; + fe_ofs_link: Z; + fe_ofs_retaddr: Z; + fe_ofs_local: Z; + fe_ofs_int_callee_save: Z; + fe_num_int_callee_save: Z; + fe_ofs_float_callee_save: Z; + fe_num_float_callee_save: Z; + fe_stack_data: Z +}. + +(** Computation of the frame environment from the bounds of the current + function. *) + +Definition make_env (b: bounds) := + let ol := align (4 * b.(bound_outgoing)) 8 in (* locals *) + let oics := ol + 4 * b.(bound_local) in (* integer callee-saves *) + let oendi := oics + 4 * b.(bound_int_callee_save) in + let ofcs := align oendi 8 in (* float callee-saves *) + let ora := ofcs + 8 * b.(bound_float_callee_save) in (* retaddr *) + let olink := ora + 4 in (* back link *) + let ostkdata := olink + 4 in (* stack data *) + let sz := align (ostkdata + b.(bound_stack_data)) 8 in + mk_frame_env sz olink ora ol + oics b.(bound_int_callee_save) + ofcs b.(bound_float_callee_save) + ostkdata. + +(** Separation property *) + +Remark frame_env_separated: + forall b, + let fe := make_env b in + 0 <= fe_ofs_arg + /\ fe_ofs_arg + 4 * b.(bound_outgoing) <= fe.(fe_ofs_local) + /\ fe.(fe_ofs_local) + 4 * b.(bound_local) <= fe.(fe_ofs_int_callee_save) + /\ fe.(fe_ofs_int_callee_save) + 4 * b.(bound_int_callee_save) <= fe.(fe_ofs_float_callee_save) + /\ fe.(fe_ofs_float_callee_save) + 8 * b.(bound_float_callee_save) <= fe.(fe_ofs_retaddr) + /\ fe.(fe_ofs_retaddr) + 4 <= fe.(fe_ofs_link) + /\ fe.(fe_ofs_link) + 4 <= fe.(fe_stack_data) + /\ fe.(fe_stack_data) + b.(bound_stack_data) <= fe.(fe_size). +Proof. + intros. + generalize (align_le (4 * bound_outgoing b) 8 (refl_equal)). + generalize (align_le (fe_ofs_int_callee_save fe + 4 * b.(bound_int_callee_save)) 8 (refl_equal _)). + generalize (align_le (fe_stack_data fe + b.(bound_stack_data)) 8 (refl_equal)). + unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, + fe_ofs_local, fe_ofs_int_callee_save, fe_num_int_callee_save, + fe_ofs_float_callee_save, fe_num_float_callee_save, + fe_stack_data, fe_ofs_arg. + intros. + generalize (bound_local_pos b); intro; + generalize (bound_int_callee_save_pos b); intro; + generalize (bound_float_callee_save_pos b); intro; + generalize (bound_outgoing_pos b); intro; + generalize (bound_stack_data_pos b); intro. + omega. +Qed. + +(** Alignment property *) + +Remark frame_env_aligned: + forall b, + let fe := make_env b in + (4 | fe.(fe_ofs_link)) + /\ (8 | fe.(fe_ofs_local)) + /\ (4 | fe.(fe_ofs_int_callee_save)) + /\ (8 | fe.(fe_ofs_float_callee_save)) + /\ (4 | fe.(fe_ofs_retaddr)) + /\ (8 | fe.(fe_stack_data)) + /\ (8 | fe.(fe_size)). +Proof. + intros. + unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, + fe_ofs_local, fe_ofs_int_callee_save, fe_num_int_callee_save, + fe_ofs_float_callee_save, fe_num_float_callee_save, + fe_stack_data. + set (x1 := 4 * bound_outgoing b). + assert (4 | x1). unfold x1; exists (bound_outgoing b); ring. + set (x2 := align x1 8). + assert (8 | x2). apply align_divides. omega. + set (x3 := x2 + 4 * bound_local b). + assert (4 | x3). apply Zdivide_plus_r. apply Zdivides_trans with 8; auto. exists 2; auto. + exists (bound_local b); ring. + set (x4 := align (x3 + 4 * bound_int_callee_save b) 8). + assert (8 | x4). apply align_divides. omega. + set (x5 := x4 + 8 * bound_float_callee_save b). + assert (8 | x5). apply Zdivide_plus_r; auto. exists (bound_float_callee_save b); ring. + assert (4 | x5). apply Zdivides_trans with 8; auto. exists 2; auto. + set (x6 := x5 + 4). + assert (4 | x6). apply Zdivide_plus_r; auto. exists 1; auto. + set (x7 := x6 + 4). + assert (8 | x7). unfold x7, x6. replace (x5 + 4 + 4) with (x5 + 8) by omega. + apply Zdivide_plus_r; auto. exists 1; auto. + set (x8 := align (x7 + bound_stack_data b) 8). + assert (8 | x8). apply align_divides. omega. + tauto. +Qed. diff --git a/arm/linux/Conventions1.v b/arm/linux/Conventions1.v deleted file mode 100644 index 1731eba..0000000 --- a/arm/linux/Conventions1.v +++ /dev/null @@ -1,453 +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 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 = 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. *) - -(** ** 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 => R0 :: nil - | Some Tfloat => F0 :: nil - | Some Tlong => R1 :: R0 :: nil - end. - -(** The result location is a caller-save register or a temporary *) - -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 float arguments are passed in registers [F0] and [F1]. -- Each float argument passed in a float register ``consumes'' an aligned pair - of two integer registers. -- Each long integer argument is passed in an aligned pair of two integer - registers. -- Extra arguments are passed on the stack, in [Outgoing] slots, consecutively - assigned (1 word for an integer argument, 2 words for a float or a long), - starting at word offset 0. -*) - -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 F1. - -Fixpoint loc_arguments_rec (tyl: list typ) (ofs: Z) {struct tyl} : list loc := - match tyl with - | nil => nil - | Tint :: tys => - (if zle 0 ofs then S Outgoing ofs Tint else R (ireg_param ofs)) - :: loc_arguments_rec tys (ofs + 1) - | Tfloat :: tys => - let ofs := align ofs 2 in - (if zle 0 ofs then S Outgoing ofs Tfloat else R (freg_param ofs)) - :: loc_arguments_rec tys (ofs + 2) - | 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 :: tys => size_arguments_rec tys (ofs + 1) - | (Tfloat | Tlong) :: 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. - -(* -Lemma align_monotone: - forall x1 x2 y, y > 0 -> x1 <= x2 -> align x1 y <= align x2 y. -Proof. - intros. unfold align. apply Zmult_le_compat_r. apply Z_div_le. - omega. omega. omega. -Qed. -*) - -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 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. -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. -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. - } - unfold size_arguments. apply H1. auto. -Qed. diff --git a/arm/linux/Stacklayout.v b/arm/linux/Stacklayout.v deleted file mode 100644 index 7694dcf..0000000 --- a/arm/linux/Stacklayout.v +++ /dev/null @@ -1,132 +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. *) -(* *) -(* *********************************************************************) - -(** Machine- and ABI-dependent layout information for activation records. *) - -Require Import Coqlib. -Require Import Bounds. - -(** The general shape of activation records is as follows, - from bottom (lowest offsets) to top: -- Space for outgoing arguments to function calls. -- Local stack slots. -- Saved values of integer callee-save registers used by the function. -- Saved values of float callee-save registers used by the function. -- Saved return address into caller. -- Pointer to activation record of the caller. -- Space for the stack-allocated data declared in Cminor. - -The [frame_env] compilation environment records the positions of -the boundaries between areas in the frame part. -*) - -Definition fe_ofs_arg := 0. - -Record frame_env : Type := mk_frame_env { - fe_size: Z; - fe_ofs_link: Z; - fe_ofs_retaddr: Z; - fe_ofs_local: Z; - fe_ofs_int_callee_save: Z; - fe_num_int_callee_save: Z; - fe_ofs_float_callee_save: Z; - fe_num_float_callee_save: Z; - fe_stack_data: Z -}. - -(** Computation of the frame environment from the bounds of the current - function. *) - -Definition make_env (b: bounds) := - let ol := align (4 * b.(bound_outgoing)) 8 in (* locals *) - let oics := ol + 4 * b.(bound_local) in (* integer callee-saves *) - let oendi := oics + 4 * b.(bound_int_callee_save) in - let ofcs := align oendi 8 in (* float callee-saves *) - let ora := ofcs + 8 * b.(bound_float_callee_save) in (* retaddr *) - let olink := ora + 4 in (* back link *) - let ostkdata := olink + 4 in (* stack data *) - let sz := align (ostkdata + b.(bound_stack_data)) 8 in - mk_frame_env sz olink ora ol - oics b.(bound_int_callee_save) - ofcs b.(bound_float_callee_save) - ostkdata. - -(** Separation property *) - -Remark frame_env_separated: - forall b, - let fe := make_env b in - 0 <= fe_ofs_arg - /\ fe_ofs_arg + 4 * b.(bound_outgoing) <= fe.(fe_ofs_local) - /\ fe.(fe_ofs_local) + 4 * b.(bound_local) <= fe.(fe_ofs_int_callee_save) - /\ fe.(fe_ofs_int_callee_save) + 4 * b.(bound_int_callee_save) <= fe.(fe_ofs_float_callee_save) - /\ fe.(fe_ofs_float_callee_save) + 8 * b.(bound_float_callee_save) <= fe.(fe_ofs_retaddr) - /\ fe.(fe_ofs_retaddr) + 4 <= fe.(fe_ofs_link) - /\ fe.(fe_ofs_link) + 4 <= fe.(fe_stack_data) - /\ fe.(fe_stack_data) + b.(bound_stack_data) <= fe.(fe_size). -Proof. - intros. - generalize (align_le (4 * bound_outgoing b) 8 (refl_equal)). - generalize (align_le (fe_ofs_int_callee_save fe + 4 * b.(bound_int_callee_save)) 8 (refl_equal _)). - generalize (align_le (fe_stack_data fe + b.(bound_stack_data)) 8 (refl_equal)). - unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, - fe_ofs_local, fe_ofs_int_callee_save, fe_num_int_callee_save, - fe_ofs_float_callee_save, fe_num_float_callee_save, - fe_stack_data, fe_ofs_arg. - intros. - generalize (bound_local_pos b); intro; - generalize (bound_int_callee_save_pos b); intro; - generalize (bound_float_callee_save_pos b); intro; - generalize (bound_outgoing_pos b); intro; - generalize (bound_stack_data_pos b); intro. - omega. -Qed. - -(** Alignment property *) - -Remark frame_env_aligned: - forall b, - let fe := make_env b in - (4 | fe.(fe_ofs_link)) - /\ (8 | fe.(fe_ofs_local)) - /\ (4 | fe.(fe_ofs_int_callee_save)) - /\ (8 | fe.(fe_ofs_float_callee_save)) - /\ (4 | fe.(fe_ofs_retaddr)) - /\ (8 | fe.(fe_stack_data)) - /\ (8 | fe.(fe_size)). -Proof. - intros. - unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, - fe_ofs_local, fe_ofs_int_callee_save, fe_num_int_callee_save, - fe_ofs_float_callee_save, fe_num_float_callee_save, - fe_stack_data. - set (x1 := 4 * bound_outgoing b). - assert (4 | x1). unfold x1; exists (bound_outgoing b); ring. - set (x2 := align x1 8). - assert (8 | x2). apply align_divides. omega. - set (x3 := x2 + 4 * bound_local b). - assert (4 | x3). apply Zdivide_plus_r. apply Zdivides_trans with 8; auto. exists 2; auto. - exists (bound_local b); ring. - set (x4 := align (x3 + 4 * bound_int_callee_save b) 8). - assert (8 | x4). apply align_divides. omega. - set (x5 := x4 + 8 * bound_float_callee_save b). - assert (8 | x5). apply Zdivide_plus_r; auto. exists (bound_float_callee_save b); ring. - assert (4 | x5). apply Zdivides_trans with 8; auto. exists 2; auto. - set (x6 := x5 + 4). - assert (4 | x6). apply Zdivide_plus_r; auto. exists 1; auto. - set (x7 := x6 + 4). - assert (8 | x7). unfold x7, x6. replace (x5 + 4 + 4) with (x5 + 8) by omega. - apply Zdivide_plus_r; auto. exists 1; auto. - set (x8 := align (x7 + bound_stack_data b) 8). - assert (8 | x8). apply align_divides. omega. - tauto. -Qed. -- cgit v1.2.3