Merge remote-tracking branch 'origin/mppa-work' into mppa-thread

4 files changed, 171 insertions, 209 deletions

diff --git a/arm/CSE2deps.v b/arm/CSE2deps.v
new file mode 100644
index 00000000..9db51bbb
--- /dev/null
+++ b/arm/CSE2deps.v
@@ -0,0 +1,20 @@
+Require Import BoolEqual Coqlib.
+Require Import AST Integers Floats.
+Require Import Values Memory Globalenvs Events.
+Require Import Op.
+
+
+Definition can_swap_accesses_ofs ofsr chunkr ofsw chunkw :=
+     (0 <=? ofsw) && (ofsw <=? (Ptrofs.modulus - largest_size_chunk))
+  && (0 <=? ofsr) && (ofsr <=? (Ptrofs.modulus - largest_size_chunk))
+  && ((ofsw + size_chunk chunkw <=? ofsr) ||
+      (ofsr + size_chunk chunkr <=? ofsw)).
+
+Definition may_overlap chunk addr args chunk' addr' args' :=
+  match addr, addr', args, args' with
+  | (Aindexed ofs), (Aindexed ofs'),
+    (base :: nil), (base' :: nil) =>
+    if peq base base'
+    then negb (can_swap_accesses_ofs (Int.unsigned ofs') chunk' (Int.unsigned ofs) chunk)
+    else true  | _, _, _, _ => true
+  end.
diff --git a/arm/CSE2depsproof.v b/arm/CSE2depsproof.v
new file mode 100644
index 00000000..61fe5980
--- /dev/null
+++ b/arm/CSE2depsproof.v
@@ -0,0 +1,129 @@
+Require Import Coqlib Maps Errors Integers Floats Lattice Kildall.
+Require Import AST Linking.
+Require Import Memory Registers Op RTL Maps.
+
+Require Import Globalenvs Values.
+Require Import Linking Values Memory Globalenvs Events Smallstep.
+Require Import Registers Op RTL.
+Require Import CSE2 CSE2deps.
+Require Import Lia.
+
+Lemma ptrofs_size :
+  Ptrofs.wordsize = 32%nat.
+Proof.
+  unfold Ptrofs.wordsize.
+  unfold Wordsize_Ptrofs.wordsize.
+  trivial.
+Qed.
+
+Lemma ptrofs_modulus :
+  Ptrofs.modulus = 4294967296.
+Proof.
+  unfold Ptrofs.modulus.
+  rewrite ptrofs_size.
+  destruct Archi.ptr64; reflexivity.
+Qed.
+
+Section SOUNDNESS.
+  Variable F V : Type.
+  Variable genv: Genv.t F V.
+  Variable sp : val.
+
+Section MEMORY_WRITE.
+  Variable m m2 : mem.
+  Variable chunkw chunkr : memory_chunk.
+  Variable base : val.
+  
+  Variable addrw addrr valw : val.
+  Hypothesis STORE : Mem.storev chunkw m addrw valw = Some m2.
+
+  Section INDEXED_AWAY.
+  Variable ofsw ofsr : int.
+  Hypothesis ADDRW : eval_addressing genv sp
+                       (Aindexed ofsw) (base :: nil) = Some addrw. 
+  Hypothesis ADDRR : eval_addressing genv sp
+                       (Aindexed ofsr) (base :: nil) = Some addrr.
+
+  Lemma load_store_away1 :
+    forall RANGEW : 0 <= Int.unsigned ofsw <= Ptrofs.modulus - largest_size_chunk,
+    forall RANGER : 0 <= Int.unsigned ofsr <= Ptrofs.modulus - largest_size_chunk,
+    forall SWAPPABLE :    Int.unsigned ofsw + size_chunk chunkw <= Int.unsigned ofsr
+                       \/ Int.unsigned ofsr + size_chunk chunkr <= Int.unsigned ofsw,
+    Mem.loadv chunkr m2 addrr = Mem.loadv chunkr m addrr.
+  Proof.
+    intros.
+    
+    pose proof (max_size_chunk chunkr) as size_chunkr_bounded.
+    pose proof (max_size_chunk chunkw) as size_chunkw_bounded.
+    unfold largest_size_chunk in *.
+
+    rewrite ptrofs_modulus in *.
+    simpl in *.
+    inv ADDRR.
+    inv ADDRW.
+    destruct base; try discriminate.
+    eapply Mem.load_store_other with (chunk := chunkw) (v := valw) (b := b).
+    exact STORE.
+    right.
+
+    all: try (destruct (Ptrofs.unsigned_add_either i (Ptrofs.of_int ofsr)) as [OFSR | OFSR];
+              rewrite OFSR).
+    all: try (destruct (Ptrofs.unsigned_add_either i (Ptrofs.of_int ofsw)) as [OFSW | OFSW];
+              rewrite OFSW).
+    
+    all: try rewrite ptrofs_modulus in *.
+
+    all: unfold Ptrofs.of_int.
+   
+    all: repeat rewrite Ptrofs.unsigned_repr by (change Ptrofs.max_unsigned with 4294967295; lia).
+    all: intuition lia.
+  Qed.
+  
+  Theorem load_store_away :
+    can_swap_accesses_ofs (Int.unsigned ofsr) chunkr (Int.unsigned ofsw) chunkw = true ->
+    Mem.loadv chunkr m2 addrr =  Mem.loadv chunkr m addrr.
+  Proof.
+    intro SWAP.
+    unfold can_swap_accesses_ofs in SWAP.
+    repeat rewrite andb_true_iff in SWAP.
+    repeat rewrite orb_true_iff in SWAP.
+    repeat rewrite Z.leb_le in SWAP.
+    apply load_store_away1.
+    all: tauto.
+  Qed.
+  End INDEXED_AWAY.
+End MEMORY_WRITE.
+End SOUNDNESS.
+
+
+Section SOUNDNESS.
+  Variable F V : Type.
+  Variable genv: Genv.t F V.
+  Variable sp : val.
+
+Lemma may_overlap_sound:
+  forall m m' : mem,
+  forall chunk addr args chunk' addr' args' v a a' rs,
+    (eval_addressing genv sp addr (rs ## args)) = Some a ->
+    (eval_addressing genv sp addr' (rs ## args')) = Some a' ->
+    (may_overlap chunk addr args chunk' addr' args') = false ->
+    (Mem.storev chunk m a v) = Some m' ->
+    (Mem.loadv chunk' m'  a') = (Mem.loadv chunk' m a').
+Proof.
+  intros until rs.
+  intros ADDR ADDR' OVERLAP STORE.
+  destruct addr; destruct addr'; try discriminate.
+  { (* Aindexed / Aindexed *)
+  destruct args as [ | base [ | ]]. 1,3: discriminate.
+  destruct args' as [ | base' [ | ]]. 1,3: discriminate.
+  simpl in OVERLAP.
+  destruct (peq base base'). 2: discriminate.
+  subst base'.
+  destruct (can_swap_accesses_ofs (Int.unsigned i0) chunk' (Int.unsigned i) chunk) eqn:SWAP.
+  2: discriminate.
+  simpl in *.
+  eapply load_store_away with (F:=F) (V:=V) (genv:=genv) (sp:=sp); eassumption.
+  }
+Qed.
+
+End SOUNDNESS.
diff --git a/arm/Conventions1.v b/arm/Conventions1.v
index 7016c1ee..fe49a781 100644
--- a/arm/Conventions1.v
+++ b/arm/Conventions1.v
@@ -269,48 +269,6 @@ Definition loc_arguments (s: signature) : list (rpair loc) :=
       else loc_arguments_hf s.(sig_args) 0 0 0
   end.
 
-(** [size_arguments s] returns the number of [Outgoing] slots used
-  to call a function with signature [s]. *)
-
-Fixpoint size_arguments_hf (tyl: list typ) (ir fr ofs: Z) {struct tyl} : Z :=
-  match tyl with
-  | nil => ofs
-  | (Tint|Tany32) :: tys =>
-      if zlt ir 4
-      then size_arguments_hf tys (ir + 1) fr ofs
-      else size_arguments_hf tys ir fr (ofs + 1)
-  | (Tfloat|Tany64) :: tys =>
-      if zlt fr 8
-      then size_arguments_hf tys ir (fr + 1) ofs
-      else size_arguments_hf tys ir fr (align ofs 2 + 2)
-  | Tsingle :: tys =>
-      if zlt fr 8
-      then size_arguments_hf tys ir (fr + 1) ofs
-      else size_arguments_hf tys ir fr (ofs + 1)
-  | Tlong :: tys =>
-      let ir := align ir 2 in
-      if zlt ir 4
-      then size_arguments_hf tys (ir + 2) fr ofs
-      else size_arguments_hf tys ir fr (align ofs 2 + 2)
-  end.
-
-Fixpoint size_arguments_sf (tyl: list typ) (ofs: Z) {struct tyl} : Z :=
-  match tyl with
-  | nil => Z.max 0 ofs
-  | (Tint | Tsingle | Tany32) :: tys => size_arguments_sf tys (ofs + 1)
-  | (Tfloat | Tlong | Tany64) :: tys => size_arguments_sf tys (align ofs 2 + 2)
-  end.
-
-Definition size_arguments (s: signature) : Z :=
-  match Archi.abi with
-  | Archi.Softfloat =>
-      size_arguments_sf s.(sig_args) (-4)
-  | Archi.Hardfloat =>
-      if s.(sig_cc).(cc_vararg)
-      then size_arguments_sf s.(sig_args) (-4)
-      else size_arguments_hf s.(sig_args) 0 0 0
-  end.
-
 (** Argument locations are either non-temporary registers or [Outgoing]
   stack slots at nonnegative offsets. *)
 
@@ -471,170 +429,6 @@ Qed.
 
 Hint Resolve loc_arguments_acceptable: locs.
 
-(** The offsets of [Outgoing] arguments are below [size_arguments s]. *)
-
-Remark size_arguments_hf_above:
-  forall tyl ir fr ofs0,
-  ofs0 <= size_arguments_hf tyl ir fr ofs0.
-Proof.
-  induction tyl; simpl; intros.
-  omega.
-  destruct a.
-  destruct (zlt ir 4); eauto. apply Z.le_trans with (ofs0 + 1); auto; omega.
-  destruct (zlt fr 8); eauto.
-  apply Z.le_trans with (align ofs0 2). apply align_le; omega.
-  apply Z.le_trans with (align ofs0 2 + 2); auto; omega.
-  set (ir' := align ir 2).
-  destruct (zlt ir' 4); eauto.
-  apply Z.le_trans with (align ofs0 2). apply align_le; omega.
-  apply Z.le_trans with (align ofs0 2 + 2); auto; omega.
-  destruct (zlt fr 8); eauto.
-  apply Z.le_trans with (ofs0 + 1); eauto. omega.
-  destruct (zlt ir 4); eauto. apply Z.le_trans with (ofs0 + 1); auto; omega.
-  destruct (zlt fr 8); eauto.
-  apply Z.le_trans with (align ofs0 2). apply align_le; omega.
-  apply Z.le_trans with (align ofs0 2 + 2); auto; omega.
-Qed.
-
-Remark size_arguments_sf_above:
-  forall tyl ofs0,
-  Z.max 0 ofs0 <= size_arguments_sf tyl ofs0.
-Proof.
-  induction tyl; simpl; intros.
-  omega.
-  destruct a; (eapply Z.le_trans; [idtac|eauto]).
-  xomega.
-  assert (ofs0 <= align ofs0 2) by (apply align_le; omega). xomega.
-  assert (ofs0 <= align ofs0 2) by (apply align_le; omega). xomega.
-  xomega.
-  xomega.
-  assert (ofs0 <= align ofs0 2) by (apply align_le; omega). xomega.
-Qed.
-
-Lemma size_arguments_above:
-  forall s, size_arguments s >= 0.
-Proof.
-  intros; unfold size_arguments. apply Z.le_ge.
-  assert (0 <= size_arguments_sf (sig_args s) (-4)).
-  { change 0 with (Z.max 0 (-4)). apply size_arguments_sf_above. }
-  assert (0 <= size_arguments_hf (sig_args s) 0 0 0).
-  { apply size_arguments_hf_above. }
-  destruct Archi.abi; [ | destruct (cc_vararg (sig_cc s)) ]; auto.
-Qed.
-
-Lemma loc_arguments_hf_bounded:
-  forall ofs ty tyl ir fr ofs0,
-  In (S Outgoing ofs ty) (regs_of_rpairs (loc_arguments_hf tyl ir fr ofs0)) ->
-  ofs + typesize ty <= size_arguments_hf tyl ir fr ofs0.
-Proof.
-  induction tyl; simpl; intros.
-  elim H.
-  destruct a.
-- (* int *)
-  destruct (zlt ir 4); destruct H.
-  discriminate.
-  eauto.
-  inv H. apply size_arguments_hf_above.
-  eauto.
-- (* float *)
-  destruct (zlt fr 8); destruct H.
-  discriminate.
-  eauto.
-  inv H. apply size_arguments_hf_above.
-  eauto.
-- (* long *)
-  destruct (zlt (align ir 2) 4).
-  destruct H. discriminate. destruct H. discriminate. eauto.
-  destruct Archi.big_endian.
-  destruct H. inv H.
-  eapply Z.le_trans. 2: apply size_arguments_hf_above. simpl; omega.
-  destruct H. inv H.
-  rewrite <- Z.add_assoc. simpl. apply size_arguments_hf_above.
-  eauto.
-  destruct H. inv H.
-  rewrite <- Z.add_assoc. simpl. apply size_arguments_hf_above.
-  destruct H. inv H.
-  eapply Z.le_trans. 2: apply size_arguments_hf_above. simpl; omega.
-  eauto.
-- (* float *)
-  destruct (zlt fr 8); destruct H.
-  discriminate.
-  eauto.
-  inv H. apply size_arguments_hf_above.
-  eauto.
-- (* any32 *)
-  destruct (zlt ir 4); destruct H.
-  discriminate.
-  eauto.
-  inv H. apply size_arguments_hf_above.
-  eauto.
-- (* any64 *)
-  destruct (zlt fr 8); destruct H.
-  discriminate.
-  eauto.
-  inv H. apply size_arguments_hf_above.
-  eauto.
-Qed.
-
-Lemma loc_arguments_sf_bounded:
-  forall ofs ty tyl ofs0,
-  In (S Outgoing ofs ty) (regs_of_rpairs (loc_arguments_sf tyl ofs0)) ->
-  Z.max 0 (ofs + typesize ty) <= size_arguments_sf tyl ofs0.
-Proof.
-  induction tyl; simpl; intros.
-  elim H.
-  destruct a.
-- (* int *)
-  destruct H.
-  destruct (zlt ofs0 0); inv H. apply size_arguments_sf_above.
-  eauto.
-- (* float *)
-  destruct H.
-  destruct (zlt (align ofs0 2) 0); inv H. apply size_arguments_sf_above.
-  eauto.
-- (* long *)
-  destruct H.
-  destruct Archi.big_endian.
-  destruct (zlt (align ofs0 2) 0); inv H.
-  eapply Z.le_trans. 2: apply size_arguments_sf_above. simpl; xomega.
-  destruct (zlt (align ofs0 2) 0); inv H.
-  rewrite <- Z.add_assoc. simpl. apply size_arguments_sf_above.
-  destruct H.
-  destruct Archi.big_endian.
-  destruct (zlt (align ofs0 2) 0); inv H.
-  rewrite <- Z.add_assoc. simpl. apply size_arguments_sf_above.
-  destruct (zlt (align ofs0 2) 0); inv H.
-  eapply Z.le_trans. 2: apply size_arguments_sf_above. simpl; xomega.
-  eauto.
-- (* float *)
-  destruct H.
-  destruct (zlt ofs0 0); inv H. apply size_arguments_sf_above.
-  eauto.
-- (* any32 *)
-  destruct H.
-  destruct (zlt ofs0 0); inv H. apply size_arguments_sf_above.
-  eauto.
-- (* any64 *)
-  destruct H.
-  destruct (zlt (align ofs0 2) 0); inv H. apply size_arguments_sf_above.
-  eauto.
-Qed.
-
-Lemma loc_arguments_bounded:
-  forall (s: signature) (ofs: Z) (ty: typ),
-  In (S Outgoing ofs ty) (regs_of_rpairs (loc_arguments s)) ->
-  ofs + typesize ty <= size_arguments s.
-Proof.
-  unfold loc_arguments, size_arguments; intros.
-  assert (In (S Outgoing ofs ty) (regs_of_rpairs (loc_arguments_sf (sig_args s) (-4))) ->
-          ofs + typesize ty <= size_arguments_sf (sig_args s) (-4)).
-  { intros. eapply Z.le_trans. 2: eapply loc_arguments_sf_bounded; eauto. xomega. }
-  assert (In (S Outgoing ofs ty) (regs_of_rpairs (loc_arguments_hf (sig_args s) 0 0 0)) ->
-          ofs + typesize ty <= size_arguments_hf (sig_args s) 0 0 0).
-  { intros. eapply loc_arguments_hf_bounded; eauto. }
-  destruct Archi.abi; [ | destruct (cc_vararg (sig_cc s)) ]; eauto.
-Qed.
-
 Lemma loc_arguments_main:
   loc_arguments signature_main = nil.
 Proof.
diff --git a/arm/DuplicateOpcodeHeuristic.ml b/arm/DuplicateOpcodeHeuristic.ml
index 85505245..9b6a6409 100644
--- a/arm/DuplicateOpcodeHeuristic.ml
+++ b/arm/DuplicateOpcodeHeuristic.ml
@@ -1,3 +1,22 @@
-exception HeuristicSucceeded
-        
-let opcode_heuristic code cond ifso ifnot preferred = ()
+open Op
+open Integers
+
+let opcode_heuristic code cond ifso ifnot is_loop_header =
+  match cond with
+  | Ccompimm (c, n) | Ccompuimm (c, n) -> if n == Integers.Int.zero then (match c with
+      | Clt | Cle -> Some false
+      | Cgt | Cge -> Some true
+      | _ -> None
+      ) else None
+  | Ccompf c | Ccompfs c -> (match c with
+      | Ceq -> Some false
+      | Cne -> Some true
+      | _ -> None
+      )
+  | Cnotcompf c | Cnotcompfs c -> (match c with
+      | Ceq -> Some true
+      | Cne -> Some false
+      | _ -> None
+      )
+  | _ -> None
+