Cleanup shouldExpose to avoid hardcoding access level, and update doc comment

Author: hyp

include/swift/IRGen/SwiftIRDetailsProvider.h

@@ -25,9 +25,8 @@ class SILModule;
 
 class IRDetailsProviderImpl;
 
-/// An abstract interface provided to \c IRDetailsVisitor that provides access
-/// to the queries that can be performed on declarations to get their various
-/// ABI details.
+/// Provides access to the IRGen-based queries that can be performed on
+/// declarations to get their various ABI details.
 class IRDetailsProvider {
 public:
   IRDetailsProvider(const IRGenOptions &opts, SILModule &SILMod);

lib/PrintAsClang/ExposedDeclFilter.h

@@ -15,12 +15,17 @@
 
 #include "OutputLanguageMode.h"
 #include "swift/AST/Decl.h"
+#include "swift/AST/Module.h"
 #include "swift/AST/SwiftNameTranslation.h"
 
 namespace swift {
 
 namespace clang_translation {
 
+inline AccessLevel getRequiredAccess(const ModuleDecl &M) {
+  return M.isExternallyConsumed() ? AccessLevel::Public : AccessLevel::Internal;
+}
+
 /// Returns true if the given declaration should be exposed in the generated
 /// Objective-C/C/C++ header, as depending on the specified output language.
 inline bool shouldExpose(const ValueDecl *VD, OutputLanguageMode outputLang,
@@ -35,7 +40,8 @@ inline bool shouldExpose(const ValueDecl *VD, OutputLanguageMode outputLang,
 /// Returns true if the given declaration should be exposed in generated
 /// Objective-C/C/C++ header, regardless of what language the declaration is
 /// exposed to.
-inline bool shouldExpose(const ValueDecl *VD, AccessLevel minRequiredAccess) {
+inline bool shouldExpose(const ValueDecl *VD, const ModuleDecl &M) {
+  auto minRequiredAccess = getRequiredAccess(M);
   return shouldExpose(VD, OutputLanguageMode::ObjC, minRequiredAccess) ||
          shouldExpose(VD, OutputLanguageMode::Cxx, minRequiredAccess);
 }

lib/PrintAsClang/ModuleContentsWriter.cpp

@@ -14,6 +14,7 @@
 
 #include "ClangSyntaxPrinter.h"
 #include "DeclAndTypePrinter.h"
+#include "ExposedDeclFilter.h"
 #include "OutputLanguageMode.h"
 #include "PrimitiveTypeMapping.h"
 
@@ -635,15 +636,12 @@ class ModuleWriter {
 };
 } // end anonymous namespace
 
-static AccessLevel getRequiredAccess(const ModuleDecl &M) {
-  return M.isExternallyConsumed() ? AccessLevel::Public : AccessLevel::Internal;
-}
-
 void swift::printModuleContentsAsObjC(
     raw_ostream &os, llvm::SmallPtrSetImpl<ImportModuleTy> &imports,
     ModuleDecl &M, SwiftToClangInteropContextImpl &interopContext) {
   llvm::raw_null_ostream prologueOS;
-  ModuleWriter(os, prologueOS, imports, M, interopContext, getRequiredAccess(M),
+  ModuleWriter(os, prologueOS, imports, M, interopContext,
+               clang_translation::getRequiredAccess(M),
                OutputLanguageMode::ObjC)
       .write();
 }
@@ -657,7 +655,7 @@ void swift::printModuleContentsAsCxx(
   llvm::raw_string_ostream prologueOS{modulePrologueBuf};
 
   ModuleWriter(moduleOS, prologueOS, imports, M, interopContext,
-               getRequiredAccess(M), OutputLanguageMode::Cxx)
+               clang_translation::getRequiredAccess(M), OutputLanguageMode::Cxx)
       .write();
 
   // FIXME: refactor.

lib/PrintAsClang/SwiftToClangInteropContext.cpp

@@ -39,7 +39,7 @@ void SwiftToClangInteropContext::collectSwiftIRGenDetails(
 
   for (auto decl : decls) {
     const auto *VD = dyn_cast<ValueDecl>(decl);
-    if (!VD || !clang_translation::shouldExpose(VD, AccessLevel::Public))
+    if (!VD || !clang_translation::shouldExpose(VD, M))
       continue;
     if (const auto *SD = dyn_cast<StructDecl>(VD)) {
       if (auto typeInfo = irDetails.getTypeSizeAlignment(SD))