Porting the BTL non-trap loads approach to RTL

1 files changed, 45 insertions, 43 deletions

diff --git a/backend/Unusedglobproof.v b/backend/Unusedglobproof.v
index aaacf9d1..b9d73a42 100644
--- a/backend/Unusedglobproof.v
+++ b/backend/Unusedglobproof.v
@@ -910,50 +910,52 @@ Proof.
   econstructor; eauto. apply set_reg_inject; auto.
 
 - (* load *)
-  assert (A: exists ta,
-               eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = Some ta
-            /\ Val.inject j a ta).
-  { apply eval_addressing_inj with (ge1 := ge) (sp1 := Vptr sp0 Ptrofs.zero) (vl1 := rs##args).
-    intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
-    apply KEPT. red. exists pc, (Iload trap chunk addr args dst pc'); auto.
-    econstructor; eauto.
-    apply regs_inject; auto.
-    assumption. }
-  destruct A as (ta & B & C).
-  exploit Mem.loadv_inject; eauto. intros (tv & D & E).
-  econstructor; split. eapply exec_Iload; eauto.
-  econstructor; eauto. apply set_reg_inject; auto.
-
-- (* load notrap1 *)
-  assert (eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = None).
-  { eapply eval_addressing_inj_none.
-    intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
-    apply KEPT. red. exists pc, (Iload NOTRAP chunk addr args dst pc'); auto.
-    econstructor; eauto.
-    rewrite Ptrofs.add_zero; reflexivity.
-    apply regs_inject; auto.
-    eassumption.
-    assumption. }
- 
-  econstructor; split. eapply exec_Iload_notrap1; eauto.
-  econstructor; eauto. apply set_reg_inject; auto.
-
-- (* load notrap2 *)
-  assert (A: exists ta,
-               eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = Some ta
-            /\ Val.inject j a ta).
-  { apply eval_addressing_inj with (ge1 := ge) (sp1 := Vptr sp0 Ptrofs.zero) (vl1 := rs##args).
-    intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
-    apply KEPT. red. exists pc, (Iload NOTRAP chunk addr args dst pc'); auto.
-    econstructor; eauto.
-    apply regs_inject; auto.
-    assumption. }
-  destruct A as (ta & B & C).
-  destruct (Mem.loadv chunk tm ta) eqn:Echunk2.
-  + econstructor; split. eapply exec_Iload; eauto.
-    econstructor; eauto. apply set_reg_inject; auto.
-  + econstructor; split. eapply exec_Iload_notrap2; eauto.
+  inv H0.
+  + assert (A: exists ta,
+                 eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = Some ta
+              /\ Val.inject j a ta).
+    { apply eval_addressing_inj with (ge1 := ge) (sp1 := Vptr sp0 Ptrofs.zero) (vl1 := rs##args).
+      intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
+      apply KEPT. red. exists pc, (Iload trap chunk addr args dst pc'); auto.
+      econstructor; eauto.
+      apply regs_inject; auto.
+      assumption. }
+    destruct A as (ta & B & C).
+    exploit Mem.loadv_inject; eauto. intros (tv & D & E).
+    econstructor; split. eapply exec_Iload; eauto. eapply has_loaded_normal; eauto.
     econstructor; eauto. apply set_reg_inject; auto.
+  + destruct (eval_addressing) eqn:EVAL in LOAD.
+    * specialize (LOAD v).
+      assert (A: exists ta,
+                   eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = Some ta
+                /\ Val.inject j v ta).
+      { apply eval_addressing_inj with (ge1 := ge) (sp1 := Vptr sp0 Ptrofs.zero) (vl1 := rs##args).
+        intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
+        apply KEPT. red. exists pc, (Iload NOTRAP chunk addr args dst pc'); auto.
+        econstructor; eauto.
+        apply regs_inject; auto.
+        assumption. }
+      destruct A as (ta & B & C).
+      destruct (Mem.loadv chunk tm ta) eqn:Echunk2.
+      ** econstructor; split. eapply exec_Iload; eauto. eapply has_loaded_normal; eauto.
+         econstructor; eauto. apply set_reg_inject; auto.
+      ** econstructor; split. eapply exec_Iload; eauto. eapply has_loaded_default; eauto.
+         intros a EVAL'; rewrite B in EVAL'; inv EVAL'. auto.
+         econstructor; eauto. apply set_reg_inject; auto.
+    * assert (eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = None).
+      { eapply eval_addressing_inj_none.
+        intros. apply symbol_address_inject. eapply match_stacks_preserves_globals; eauto.
+        apply KEPT. red. exists pc, (Iload NOTRAP chunk addr args dst pc'); auto.
+        econstructor; eauto.
+        rewrite Ptrofs.add_zero; reflexivity.
+        apply regs_inject; auto.
+        eassumption.
+        assumption. }
+     
+      econstructor; split. eapply exec_Iload; eauto. eapply has_loaded_default; eauto.
+      intros a EVAL'; rewrite H0 in EVAL'; inv EVAL'.
+      econstructor; eauto. apply set_reg_inject; auto.
+
 - (* store *)
   assert (A: exists ta,
                eval_addressing tge (Vptr tsp Ptrofs.zero) addr trs##args = Some ta