Make AsValid TC search not loop when there is no instance to be found.

theories/proofmode/monpred.v

@@ -96,29 +96,29 @@ Global Instance from_assumption_make_monPred_ex P Q :
 Proof. intros ?. by rewrite /FromAssumption -monPred_ex_intro. Qed.
 
 Global Instance as_valid_monPred_at φ P (Φ : I → PROP) :
-  AsValid φ P → (∀ i, MakeMonPredAt i P (Φ i)) → AsValid' φ (∀ i, Φ i) | 100.
+  AsValid0 φ P → (∀ i, MakeMonPredAt i P (Φ i)) → AsValid φ (∀ i, Φ i) | 100.
 Proof.
-  rewrite /MakeMonPredAt /AsValid' /AsValid /bi_valid=> -> EQ.
+  rewrite /MakeMonPredAt /AsValid0 /AsValid /bi_valid=> -> EQ.
   setoid_rewrite <-EQ. split.
   - move=>[H]. apply bi.forall_intro=>i. rewrite -H. by rewrite monPred_at_emp.
   - move=>HP. split=>i. rewrite monPred_at_emp HP bi.forall_elim //.
 Qed.
 Global Instance as_valid_monPred_at_wand φ P Q (Φ Ψ : I → PROP) :
-  AsValid φ (P -∗ Q) →
+  AsValid0 φ (P -∗ Q) →
   (∀ i, MakeMonPredAt i P (Φ i)) → (∀ i, MakeMonPredAt i Q (Ψ i)) →
-  AsValid' φ (∀ i, Φ i -∗ Ψ i).
+  AsValid φ (∀ i, Φ i -∗ Ψ i).
 Proof.
-  rewrite /AsValid' /AsValid /MakeMonPredAt. intros -> EQ1 EQ2.
+  rewrite /AsValid0 /AsValid /MakeMonPredAt. intros -> EQ1 EQ2.
   setoid_rewrite <-EQ1. setoid_rewrite <-EQ2. split.
   - move=>/bi.wand_entails HP. setoid_rewrite HP. by iIntros (i) "$".
   - move=>HP. apply bi.entails_wand. split=>i. iIntros "H". by iApply HP.
 Qed.
 Global Instance as_valid_monPred_at_equiv φ P Q (Φ Ψ : I → PROP) :
-  AsValid φ (P ∗-∗ Q) →
+  AsValid0 φ (P ∗-∗ Q) →
   (∀ i, MakeMonPredAt i P (Φ i)) → (∀ i, MakeMonPredAt i Q (Ψ i)) →
-  AsValid' φ (∀ i, Φ i ∗-∗ Ψ i).
+  AsValid φ (∀ i, Φ i ∗-∗ Ψ i).
 Proof.
-  rewrite /AsValid' /AsValid /MakeMonPredAt. intros -> EQ1 EQ2.
+  rewrite /AsValid0 /AsValid /MakeMonPredAt. intros -> EQ1 EQ2.
   setoid_rewrite <-EQ1. setoid_rewrite <-EQ2. split.
   - move=>/bi.wand_iff_equiv HP. setoid_rewrite HP. iIntros. iSplit; iIntros "$".
   - move=>HP. apply bi.equiv_wand_iff. split=>i. by iSplit; iIntros; iApply HP.

theories/proofmode/tactics.v

@@ -57,27 +57,28 @@ Tactic Notation "iMatchHyp" tactic1(tac) :=
 Class AsValid {PROP : bi} (φ : Prop) (P : PROP) := as_valid : φ ↔ P.
 Arguments AsValid {_} _%type _%I.
 
+Class AsValid0 {PROP : bi} (φ : Prop) (P : PROP) :=
+  as_valid_here : AsValid φ P.
+Arguments AsValid0 {_} _%type _%I.
+Existing Instance as_valid_here | 0.
+
 Lemma as_valid_1 (φ : Prop) {PROP : bi} (P : PROP) `{!AsValid φ P} : φ → P.
 Proof. by apply as_valid. Qed.
 Lemma as_valid_2 (φ : Prop) {PROP : bi} (P : PROP) `{!AsValid φ P} : P → φ.
 Proof. by apply as_valid. Qed.
 
-Instance as_valid_valid {PROP : bi} (P : PROP) : AsValid (bi_valid P) P | 0.
+Instance as_valid_valid {PROP : bi} (P : PROP) : AsValid0 (bi_valid P) P | 0.
 Proof. by rewrite /AsValid. Qed.
 
-Instance as_valid_entails {PROP : bi} (P Q : PROP) : AsValid (P ⊢ Q) (P -∗ Q) | 0.
+Instance as_valid_entails {PROP : bi} (P Q : PROP) : AsValid0 (P ⊢ Q) (P -∗ Q).
 Proof. split. apply bi.entails_wand. apply bi.wand_entails. Qed.
 
-Instance as_valid_equiv {PROP : bi} (P Q : PROP) : AsValid (P ≡ Q) (P ∗-∗ Q) | 0.
+Instance as_valid_equiv {PROP : bi} (P Q : PROP) : AsValid0 (P ≡ Q) (P ∗-∗ Q).
 Proof. split. apply bi.equiv_wand_iff. apply bi.wand_iff_equiv. Qed.
 
-Class AsValid' {PROP : bi} (φ : Prop) (P : PROP) := as_valid' :> AsValid φ P.
-Arguments AsValid' {_} _%type _%I.
-Hint Mode AsValid' ! ! - : typeclass_instances.
-
 Instance as_valid_embed `{BiEmbedding PROP PROP'} (φ : Prop) (P : PROP) :
-  AsValid φ P → AsValid' φ ⎡P⎤.
-Proof. rewrite /AsValid' /AsValid=> ->. rewrite bi_embed_valid //. Qed.
+  AsValid0 φ P → AsValid φ ⎡P⎤.
+Proof. rewrite /AsValid0 /AsValid=> ->. rewrite bi_embed_valid //. Qed.
 
 (** * Start a proof *)
 Tactic Notation "iStartProof" uconstr(PROP) :=