SILCloner: Fix logic error when cloning without a substitution map

If we have no substitution map, we still substitute types appearing
in the original function, because we need to remap any local
archetypes, which are always cloned.

However, the conformance lookup callback used for this substitution
was wrong. We should only do mapTypeOutOfContext() if we're going
to callSubstitutionMap::lookupConformance(), otherwise we form a
new abstract conformance with an interface type, and not a primary
archetype as expected.

Author: slavapestov

include/swift/SIL/SILCloner.h

@@ -86,11 +86,12 @@ struct SubstitutionMapWithLocalArchetypes {
     if (origType->is<LocalArchetypeType>())
       return swift::lookupConformance(origType.subst(IFS), proto);
 
-    if (origType->is<PrimaryArchetypeType>() ||
-        origType->is<PackArchetypeType>())
-      origType = origType->mapTypeOutOfContext();
-
     if (SubsMap) {
+      if (origType->is<PrimaryArchetypeType>() ||
+          origType->is<PackArchetypeType>()) {
+        origType = origType->mapTypeOutOfContext();
+      }
+
       return SubsMap->lookupConformance(
         origType->getCanonicalType(), proto);
     }

test/SILOptimizer/sil_cloner_no_substitution_map.sil

@@ -0,0 +1,44 @@
+// RUN: %target-sil-opt %s -mandatory-allocbox-to-stack
+
+// This tickled a bug in the SILCloner that was caught by the verifier.
+
+sil_stage raw
+
+import Builtin
+import Swift
+import SwiftShims
+
+protocol P {
+    associatedtype A
+}
+
+protocol Q: AnyObject {
+}
+
+struct S: P {
+  typealias A = Int
+}
+
+sil [ossa] @testit : $@convention(thin) (Int, @guaranteed any Q, @in_guaranteed Int, @in_guaranteed S) -> () {
+bb0(%0 : $Int, %3 : @guaranteed $any Q, %4 : $*Int, %5 : $*S):
+  %6 = alloc_box ${ var Int }, var, name "duration"
+  %7 = begin_borrow [var_decl] %6
+  %8 = project_box %7, 0
+  store %0 to [trivial] %8
+  %66 = function_ref @closure : $@convention(thin) <τ_0_0, τ_0_1 where τ_0_0 == τ_0_1.A, τ_0_1 : P> (@in_guaranteed τ_0_0, @in_guaranteed τ_0_1, @guaranteed { var Int }, @guaranteed any Q) -> ()
+  %67 = apply %66<Int, S>(%4, %5, %7, %3) : $@convention(thin) <τ_0_0, τ_0_1 where τ_0_0 == τ_0_1.A, τ_0_1 : P> (@in_guaranteed τ_0_0, @in_guaranteed τ_0_1, @guaranteed { var Int }, @guaranteed any Q) -> ()
+  end_borrow %7
+  destroy_value %6
+  %75 = tuple ()
+  return %75
+}
+
+sil private [ossa] @closure : $@convention(thin) <T, V where T == V.A, V : P> (@in_guaranteed T, @in_guaranteed V, @guaranteed { var Int }, @guaranteed any Q) -> () {
+bb0(%0 : $*T, %1 : $*V, %2 : @closureCapture @guaranteed ${ var Int }, %3 : @closureCapture @guaranteed $any Q):
+  %13 = open_existential_ref %3 to $@opened("891BD9C8-56A2-11F0-A4DF-0EA13E3AABAF", any Q) Self
+  %17 = apply undef<@opened("891BD9C8-56A2-11F0-A4DF-0EA13E3AABAF", any Q) Self, V>(%0, %1) : $@convention(thin) <τ_0_0><τ_1_0 where τ_1_0 : P> (@in_guaranteed τ_1_0.A, @in_guaranteed τ_1_0) -> ()
+  %20 = tuple ()
+  return %20
+}
+
+