Merge pull request swiftlang#30365 from jckarter/substitution-map-mismatches

Create an inherited conformance in SubstitutionMap::lookupConformance when needed.

Author: jckarter

include/swift/Basic/LangOptions.h

@@ -322,6 +322,9 @@ namespace swift {
     /// `@differentiable` declaration attribute, etc.
     bool EnableExperimentalDifferentiableProgramming = false;
 
+    /// Enable verification when every SubstitutionMap is constructed.
+    bool VerifyAllSubstitutionMaps = false;
+
     /// Sets the target we are building for and updates platform conditions
     /// to match.
     ///
@@ -512,6 +515,7 @@ namespace swift {
     /// Enable constraint solver support for experimental
     ///        operator protocol designator feature.
     bool SolverEnableOperatorDesignatedTypes = false;
+    
   };
 } // end namespace swift
 

include/swift/Option/FrontendOptions.td

@@ -548,6 +548,9 @@ def sil_merge_partial_modules : Flag<["-"], "sil-merge-partial-modules">,
 
 def sil_verify_all : Flag<["-"], "sil-verify-all">,
   HelpText<"Verify SIL after each transform">;
+  
+def verify_all_substitution_maps : Flag<["-"], "verify-all-substitution-maps">,
+  HelpText<"Verify all SubstitutionMaps on construction">;
 
 def sil_debug_serialization : Flag<["-"], "sil-debug-serialization">,
   HelpText<"Do not eliminate functions in Mandatory Inlining/SILCombine dead "

lib/AST/ASTDumper.cpp

@@ -3679,8 +3679,26 @@ namespace {
 
     void visitSILFunctionType(SILFunctionType *T, StringRef label) {
       printCommon(label, "sil_function_type");
-      // FIXME: Print the structure of the type.
       printField("type", T->getString());
+
+      for (auto param : T->getParameters()) {
+        printRec("input", param.getInterfaceType());
+      }
+      for (auto yield : T->getYields()) {
+        printRec("yield", yield.getInterfaceType());
+      }
+      for (auto result : T->getResults()) {
+        printRec("result", result.getInterfaceType());
+      }
+      if (auto error  = T->getOptionalErrorResult()) {
+        printRec("error", error->getInterfaceType());
+      }
+      OS << '\n';
+      T->getPatternSubstitutions().dump(OS, SubstitutionMap::DumpStyle::Full,
+                                        Indent+2);
+      OS << '\n';
+      T->getInvocationSubstitutions().dump(OS, SubstitutionMap::DumpStyle::Full,
+                                           Indent+2);
       PrintWithColorRAII(OS, ParenthesisColor) << ')';
     }
 

lib/AST/SubstitutionMap.cpp

@@ -56,7 +56,12 @@ SubstitutionMap::SubstitutionMap(
                                 GenericSignature genericSig,
                                 ArrayRef<Type> replacementTypes,
                                 ArrayRef<ProtocolConformanceRef> conformances)
-  : storage(Storage::get(genericSig, replacementTypes, conformances)) { }
+  : storage(Storage::get(genericSig, replacementTypes, conformances)) {
+#ifndef NDEBUG
+  if (genericSig->getASTContext().LangOpts.VerifyAllSubstitutionMaps)
+    verify();
+#endif
+}
 
 ArrayRef<Type> SubstitutionMap::getReplacementTypesBuffer() const {
   return storage ? storage->getReplacementTypes() : ArrayRef<Type>();
@@ -355,8 +360,10 @@ SubstitutionMap::lookupConformance(CanType type, ProtocolDecl *proto) const {
   // Check whether the superclass conforms.
   if (auto superclass = genericSig->getSuperclassBound(type)) {
     LookUpConformanceInSignature lookup(getGenericSignature().getPointer());
-    if (auto conformance = lookup(type->getCanonicalType(), superclass, proto))
+    auto substType = type.subst(*this);
+    if (auto conformance = lookup(type->getCanonicalType(), substType, proto)){
       return conformance;
+    }
   }
 
   // If the type doesn't conform to this protocol, the result isn't formed
@@ -474,7 +481,7 @@ SubstitutionMap SubstitutionMap::subst(TypeSubstitutionFn subs,
       newConformances.push_back(
         conformance.subst(substType, subs, conformances, options));
     }
-
+    
     oldConformances = oldConformances.slice(1);
   }
 
@@ -657,6 +664,7 @@ void SubstitutionMap::verify() const {
     if (req.getKind() != RequirementKind::Conformance)
       continue;
 
+    SWIFT_DEFER { ++conformanceIndex; };
     auto substType = req.getFirstType().subst(*this);
     if (substType->isTypeParameter() ||
         substType->is<ArchetypeType>() ||
@@ -677,15 +685,44 @@ void SubstitutionMap::verify() const {
       llvm::dbgs() << "SubstitutionMap:\n";
       dump(llvm::dbgs());
       llvm::dbgs() << "\n";
+      llvm::dbgs() << "Requirement:\n";
+      req.dump(llvm::dbgs());
+      llvm::dbgs() << "\n";
     }
     assert(conformance.isConcrete() && "Conformance should be concrete");
+    
+    if (substType->is<UnboundGenericType>())
+      continue;
+    
+    auto conformanceTy = conformance.getConcrete()->getType();
+    if (conformanceTy->hasTypeParameter()
+        && !substType->hasTypeParameter()) {
+      conformanceTy = conformance.getConcrete()->getDeclContext()
+        ->mapTypeIntoContext(conformanceTy);
+    }
+    
+    if (!substType->isEqual(conformanceTy)) {
+      llvm::dbgs() << "Conformance must match concrete replacement type:\n";
+      substType->dump(llvm::dbgs());
+      llvm::dbgs() << "Conformance type:\n";
+      conformance.getConcrete()->getType()->dump(llvm::dbgs());
+      llvm::dbgs() << "Conformance:\n";
+      conformance.dump(llvm::dbgs());
+      llvm::dbgs() << "\n";
+      llvm::dbgs() << "SubstitutionMap:\n";
+      dump(llvm::dbgs());
+      llvm::dbgs() << "\n";
+      llvm::dbgs() << "Requirement:\n";
+      req.dump(llvm::dbgs());
+      llvm::dbgs() << "\n";
+    }
+    assert(substType->isEqual(conformanceTy)
+           && "conformance should match corresponding type");
 
     if (substType->isExistentialType()) {
       assert(isa<SelfProtocolConformance>(conformance.getConcrete()) &&
               "Existential type cannot have normal conformance");
     }
-
-    ++conformanceIndex;
   }
 #endif
 }

lib/AST/Type.cpp

@@ -2400,7 +2400,7 @@ getForeignRepresentable(Type type, ForeignLanguage language,
 
   if (wasOptional && !result.isRepresentableAsOptional())
     return failure();
-
+  
   // If our nominal type has type arguments, make sure they are
   // representable as well. Because type arguments are not actually
   // translated separately, whether they are trivially representable
@@ -2447,6 +2447,16 @@ getForeignRepresentable(Type type, ForeignLanguage language,
         break;
       }
     }
+    
+    // Specialize the conformance we were given for the type we're testing.
+    if (result.getKind() == ForeignRepresentableKind::Bridged
+        && !result.getConformance()->getType()->isEqual(type)) {
+      auto specialized = type->getASTContext()
+        .getSpecializedConformance(type, result.getConformance(),
+             boundGenericType->getContextSubstitutionMap(dc->getParentModule(),
+                                                 boundGenericType->getDecl()));
+      result = ForeignRepresentationInfo::forBridged(specialized);
+    }
   }
 
   return { result.getKind(), result.getConformance() };

lib/Frontend/CompilerInvocation.cpp

@@ -565,6 +565,8 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
                    Target.isOSDarwin());
   Opts.EnableSILOpaqueValues |= Args.hasArg(OPT_enable_sil_opaque_values);
 
+  Opts.VerifyAllSubstitutionMaps |= Args.hasArg(OPT_verify_all_substitution_maps);
+
   Opts.UseDarwinPreStableABIBit =
     (Target.isMacOSX() && Target.isMacOSXVersionLT(10, 14, 4)) ||
     (Target.isiOS() && Target.isOSVersionLT(12, 2)) ||
@@ -795,7 +797,7 @@ static bool ParseSearchPathArgs(SearchPathOptions &Opts,
   // Assumes exactly one of setMainExecutablePath() or setRuntimeIncludePath() 
   // is called before setTargetTriple() and parseArgs().
   // TODO: improve the handling of RuntimeIncludePath.
-
+  
   return false;
 }
 

lib/SILGen/SILGenType.cpp

@@ -749,7 +749,7 @@ static SILFunction *emitSelfConformanceWitness(SILGenModule &SGM,
   auto protocolType = protocol->getDeclaredInterfaceType();
   auto reqtSubs = SubstitutionMap::getProtocolSubstitutions(protocol,
                                           protocolType,
-                                          ProtocolConformanceRef(protocol));
+                                          ProtocolConformanceRef(conformance));
 
   // Open the protocol type.
   auto openedType = OpenedArchetypeType::get(protocolType);

test/SILGen/function_type_lowering_inherited_conformance.swift

@@ -0,0 +1,15 @@
+// RUN: %target-swift-emit-silgen %s | %FileCheck %s
+protocol P {}
+
+class C: P {}
+class D: C {}
+
+struct Butt<T: P> {}
+
+func foo<T: P>(_: (Butt<T>) -> ()) {}
+
+// CHECK-LABEL: sil{{.*}}3bar
+func bar(_ f: (Butt<D>) -> ()) {
+  // CHECK: convert_function {{.*}} $@noescape @callee_guaranteed (Butt<D>) -> () to $@noescape @callee_guaranteed @substituted <τ_0_0 where τ_0_0 : P> (Butt<τ_0_0>) -> () for <D>
+  foo(f)
+}