Module RegOrd := OrderedIndexed (IndexedMreg).Module RegSet := FSetAVL.Make (RegOrd).(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.(** * Resource bounds for a function *)

(** The [bounds] record capture how many local and outgoing stack slots
  and callee-save registers are used by a function. *)

(** We demand that all bounds are positive or null.
  These properties are used later to reason about the layout of
  the activation record. *)

Record bounds : Type := mkbounds {
  used_callee_save: list mreg;
  bound_local: Z;
  bound_outgoing: Z;
  bound_stack_data: Z;
  bound_local_pos: bound_local >= 0;
  bound_outgoing_pos: bound_outgoing >= 0;
  bound_stack_data_pos: bound_stack_data >= 0;
  used_callee_save_norepet: list_norepet used_callee_save;
  used_callee_save_prop: forall r, In r used_callee_save -> is_callee_save r = true
}.Definition mreg_within_bounds (r: mreg) :=
  is_callee_save r = true -> In r (used_callee_save b).Definition slot_within_bounds (sl: slot) (ofs: Z) (ty: typ) :=
  match sl with
  | Local => ofs + typesize ty <= bound_local b
  | Outgoing => ofs + typesize ty <= bound_outgoing b
  | Incoming => True
  end.Definition instr_within_bounds (i: instruction) :=
  match i with
  | Lgetstack sl ofs ty r => slot_within_bounds sl ofs ty /\ mreg_within_bounds r
  | Lsetstack r sl ofs ty => slot_within_bounds sl ofs ty
  | Lop op args res => mreg_within_bounds res
  | Lload chunk addr args dst => mreg_within_bounds dst
  | Lcall sig ros => size_arguments sig <= bound_outgoing b
  | Lbuiltin ef args res =>
       (forall r, In r (params_of_builtin_res res) \/ In r (destroyed_by_builtin ef) -> mreg_within_bounds r)
    /\ (forall sl ofs ty, In (S sl ofs ty) (params_of_builtin_args args) -> slot_within_bounds sl ofs ty)
  | _ => True
  end.Definition function_within_bounds (f: function) (b: bounds) : Prop :=
  forall instr, In instr f.(fn_code) -> instr_within_bounds b instr.Definition record_reg (u: RegSet.t) (r: mreg) : RegSet.t :=
  if is_callee_save r then RegSet.add r u else u.Definition record_regs (u: RegSet.t) (rl: list mreg) : RegSet.t :=
  fold_left record_reg rl u.(** In the proof of the [Stacking] pass, we only need to bound the
  registers written by an instruction.  Therefore, we examine the
  result registers only, not the argument registers. *)

Definition record_regs_of_instr (u: RegSet.t) (i: instruction) : RegSet.t :=
  match i with
  | Lgetstack sl ofs ty r => record_reg u r
  | Lsetstack r sl ofs ty => record_reg u r
  | Lop op args res => record_reg u res
  | Lload chunk addr args dst => record_reg u dst
  | Lstore chunk addr args src => u
  | Lcall sig ros => u
  | Ltailcall sig ros => u
  | Lbuiltin ef args res =>
      record_regs (record_regs u (params_of_builtin_res res)) (destroyed_by_builtin ef)
  | Llabel lbl => u
  | Lgoto lbl => u
  | Lcond cond args lbl => u
  | Ljumptable arg tbl => u
  | Lreturn => u
  end.Definition record_regs_of_function : RegSet.t :=
  fold_left record_regs_of_instr f.(fn_code) RegSet.empty.Fixpoint slots_of_locs (l: list loc) : list (slot * Z * typ) :=
  match l with
  | nil => nil
  | S sl ofs ty :: l' => (sl, ofs, ty) :: slots_of_locs l'
  | R r :: l' => slots_of_locs l'
  end.Definition slots_of_instr (i: instruction) : list (slot * Z * typ) :=
  match i with
  | Lgetstack sl ofs ty r => (sl, ofs, ty) :: nil
  | Lsetstack r sl ofs ty => (sl, ofs, ty) :: nil
  | Lbuiltin ef args res => slots_of_locs (params_of_builtin_args args)
  | _ => nil
  end.Definition max_over_list {A: Type} (valu: A -> Z) (l: list A) : Z :=
  List.fold_left (fun m l => Z.max m (valu l)) l 0.Definition max_over_instrs (valu: instruction -> Z) : Z :=
  max_over_list valu f.(fn_code).Definition max_over_slots_of_instr (valu: slot * Z * typ -> Z) (i: instruction) : Z :=
  max_over_list valu (slots_of_instr i).Definition max_over_slots_of_funct (valu: slot * Z * typ -> Z) : Z :=
  max_over_instrs (max_over_slots_of_instr valu).Definition local_slot (s: slot * Z * typ) :=
  match s with (Local, ofs, ty) => ofs + typesize ty | _ => 0 end.Definition outgoing_slot (s: slot * Z * typ) :=
  match s with (Outgoing, ofs, ty) => ofs + typesize ty | _ => 0 end.Definition outgoing_space (i: instruction) :=
  match i with Lcall sig _ => size_arguments sig | _ => 0 end.

Lemma max_over_list_pos: forall (A: Type) (valu: A -> Z) (l: list A), max_over_list valu l >= 0.