Merge pull request #66107 from mikeash/standard-concurrency-manglings-go-faster

[Runtime] Fast lookups of Concurrency types with standard manglings.

Author: mikeash

include/swift/Runtime/Metadata.h

@@ -992,6 +992,21 @@ void swift_enableDynamicReplacementScope(const DynamicReplacementScope *scope);
 SWIFT_RUNTIME_EXPORT
 void swift_disableDynamicReplacementScope(const DynamicReplacementScope *scope);
 
+/// A struct containing pointers to all of the type descriptors in the
+/// Concurrency runtime which have standard manglings.
+struct ConcurrencyStandardTypeDescriptors {
+#define STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#define STANDARD_TYPE_CONCURRENCY(KIND, MANGLING, TYPENAME)                    \
+  const ContextDescriptor *TYPENAME;
+#include "swift/Demangling/StandardTypesMangling.def"
+};
+
+/// Register the type descriptors with standard manglings from the Concurrency
+/// runtime. The passed-in struct must be immortal.
+SWIFT_RUNTIME_STDLIB_SPI
+void _swift_registerConcurrencyStandardTypeDescriptors(
+    const ConcurrencyStandardTypeDescriptors *descriptors);
+
 #pragma clang diagnostic pop
 
 } // end namespace swift

stdlib/public/Concurrency/CMakeLists.txt

@@ -107,6 +107,7 @@ add_swift_target_library(swift_Concurrency ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} I
   GlobalActor.swift
   MainActor.swift
   PartialAsyncTask.swift
+  Setup.cpp
   SourceCompatibilityShims.swift
   Task.cpp
   Task.swift

stdlib/public/Concurrency/Setup.cpp

@@ -0,0 +1,47 @@
+//===--- Setup.cpp - Load-time setup code ---------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include "swift/Runtime/Metadata.h"
+
+// Helper macros for figuring out the mangled name of a context descriptor.
+#define DESCRIPTOR_MANGLING_SUFFIX_Structure Mn
+#define DESCRIPTOR_MANGLING_SUFFIX_Class Mn
+#define DESCRIPTOR_MANGLING_SUFFIX_Enum Mn
+#define DESCRIPTOR_MANGLING_SUFFIX_Protocol Mp
+
+#define DESCRIPTOR_MANGLING_SUFFIX_(X) X
+#define DESCRIPTOR_MANGLING_SUFFIX(KIND)                                       \
+  DESCRIPTOR_MANGLING_SUFFIX_(DESCRIPTOR_MANGLING_SUFFIX_##KIND)
+
+#define DESCRIPTOR_MANGLING_(CHAR, SUFFIX) $sSc##CHAR##SUFFIX
+#define DESCRIPTOR_MANGLING(CHAR, SUFFIX) DESCRIPTOR_MANGLING_(CHAR, SUFFIX)
+
+// Declare context descriptors for all of the concurrency descriptors with
+// standard manglings.
+#define STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#define STANDARD_TYPE_CONCURRENCY(KIND, MANGLING, TYPENAME)                    \
+  extern "C" const swift::ContextDescriptor DESCRIPTOR_MANGLING(               \
+      MANGLING, DESCRIPTOR_MANGLING_SUFFIX(KIND));
+#include "swift/Demangling/StandardTypesMangling.def"
+
+// Register our type descriptors with standard manglings when the concurrency
+// runtime is loaded. This allows the runtime to quickly resolve those standard
+// manglings.
+__attribute__((constructor)) static void setupStandardConcurrencyDescriptors() {
+  static const swift::ConcurrencyStandardTypeDescriptors descriptors = {
+#define STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#define STANDARD_TYPE_CONCURRENCY(KIND, MANGLING, TYPENAME)                    \
+  &DESCRIPTOR_MANGLING(MANGLING, DESCRIPTOR_MANGLING_SUFFIX(KIND)),
+#include "swift/Demangling/StandardTypesMangling.def"
+  };
+  _swift_registerConcurrencyStandardTypeDescriptors(&descriptors);
+}

stdlib/public/runtime/MetadataLookup.cpp

@@ -770,6 +770,8 @@ _searchTypeMetadataRecords(TypeMetadataPrivateState &T,
 
 #include "swift/Demangling/StandardTypesMangling.def"
 
+static const ConcurrencyStandardTypeDescriptors *concurrencyDescriptors;
+
 static const ContextDescriptor *
 _findContextDescriptor(Demangle::NodePointer node,
                        Demangle::Demangler &Dem) {
@@ -797,7 +799,10 @@ _findContextDescriptor(Demangle::NodePointer node,
     }
   // FIXME: When the _Concurrency library gets merged into the Standard Library,
   // we will be able to reference those symbols directly as well.
-#define STANDARD_TYPE_CONCURRENCY(KIND, MANGLING, TYPENAME)
+#define STANDARD_TYPE_CONCURRENCY(KIND, MANGLING, TYPENAME)                    \
+  if (concurrencyDescriptors && name.equals(#TYPENAME)) {                      \
+    return concurrencyDescriptors->TYPENAME;                                   \
+  }
 #if !SWIFT_OBJC_INTEROP
 # define OBJC_INTEROP_STANDARD_TYPE(KIND, MANGLING, TYPENAME)
 #endif
@@ -851,6 +856,11 @@ _findContextDescriptor(Demangle::NodePointer node,
   return foundContext;
 }
 
+void swift::_swift_registerConcurrencyStandardTypeDescriptors(
+    const ConcurrencyStandardTypeDescriptors *descriptors) {
+  concurrencyDescriptors = descriptors;
+}
+
 #pragma mark Protocol descriptor cache
 namespace {
   struct ProtocolSection {