Merge pull request #27658 from DougGregor/legacy-type-layout-vfs

[IRGen] Query the VFS for legacy type layouts.

Author: DougGregor

lib/IRGen/GenType.cpp

@@ -1105,8 +1105,9 @@ TypeConverter::createImmovable(llvm::Type *type, Size size, Alignment align) {
 
 static TypeInfo *invalidTypeInfo() { return (TypeInfo*) 1; }
 
-bool TypeConverter::readLegacyTypeInfo(StringRef path) {
-  auto fileOrErr = llvm::MemoryBuffer::getFile(path);
+bool TypeConverter::readLegacyTypeInfo(llvm::vfs::FileSystem &fs,
+                                       StringRef path) {
+  auto fileOrErr = fs.getBufferForFile(path);
   if (!fileOrErr)
     return true;
 
@@ -1209,6 +1210,8 @@ TypeConverter::TypeConverter(IRGenModule &IGM)
   llvm::SmallString<128> defaultPath;
 
   StringRef path = IGM.IRGen.Opts.ReadLegacyTypeInfoPath;
+  auto fs =
+      IGM.getSwiftModule()->getASTContext().SourceMgr.getFileSystem();
   if (path.empty()) {
     const auto &Triple = IGM.Context.LangOpts.Target;
 
@@ -1225,7 +1228,7 @@ TypeConverter::TypeConverter(IRGenModule &IGM)
     bool found = false;
     for (auto &RuntimeLibraryPath
          : IGM.Context.SearchPathOpts.RuntimeLibraryPaths) {
-      if (llvm::sys::fs::exists(RuntimeLibraryPath)) {
+      if (fs->exists(RuntimeLibraryPath)) {
         defaultPath.append(RuntimeLibraryPath);
         found = true;
         break;
@@ -1245,7 +1248,7 @@ TypeConverter::TypeConverter(IRGenModule &IGM)
     path = defaultPath;
   }
 
-  bool error = readLegacyTypeInfo(path);
+  bool error = readLegacyTypeInfo(*fs, path);
   if (error)
     llvm::report_fatal_error("Cannot read '" + path + "'");
 }

lib/IRGen/GenType.h

@@ -208,7 +208,7 @@ class TypeConverter {
 
   /// Read a YAML legacy type layout dump. Returns false on success, true on
   /// error.
-  bool readLegacyTypeInfo(StringRef path);
+  bool readLegacyTypeInfo(llvm::vfs::FileSystem &fs, StringRef path);
 
   Optional<YAMLTypeInfoNode> getLegacyTypeInfo(NominalTypeDecl *decl) const;
 

test/IRGen/Inputs/legacy_type_info/vfsoverlay.yaml

@@ -0,0 +1,14 @@
+{
+  'version': 0,
+  'use-external-names': false,
+  'roots': [
+    {
+      'name': 'OUT_DIR', 'type': 'directory',
+      'contents': [
+        { 'name': 'a_moved.yaml', 'type': 'file',
+          'external-contents': 'INPUT_DIR/legacy_type_info/a.yaml'
+        },
+      ]
+    },
+  ]
+}

test/IRGen/class_update_callback_with_fixed_layout.sil

@@ -4,6 +4,10 @@
 // RUN: %target-swift-frontend  -I %t -emit-ir -enable-library-evolution %s -read-legacy-type-info-path=%S/Inputs/legacy_type_info/a.yaml | %FileCheck %s --check-prefix=CHECK --check-prefix=CHECK-%target-ptrsize -DINT=i%target-ptrsize
 // RUN: %target-swift-frontend  -I %t -emit-ir -enable-library-evolution -O %s -read-legacy-type-info-path=%S/Inputs/legacy_type_info/a.yaml
 
+// Verify that this feature works with the VFS.
+// RUN: sed -e "s|INPUT_DIR|%/S/Inputs|g" -e "s|OUT_DIR|%/t|g" %S/Inputs/legacy_type_info/vfsoverlay.yaml > %t/overlay.yaml
+// RUN: %target-swift-frontend -vfsoverlay %/t/overlay.yaml -I %t -emit-ir -enable-library-evolution -O %s -read-legacy-type-info-path=%t/a_moved.yaml
+
 // We only use fragile class layouts when Objective-C interop is enabled.
 
 // REQUIRES: objc_interop