Merge pull request #27185 from jckarter/fast-path-short-mangling-lookups

Runtime: Fast path lookup for short manglings.

Author: jckarter

include/swift/Demangling/StandardTypesMangling.def

@@ -13,10 +13,18 @@
 /// STANDARD_TYPE(KIND, MANGLING, TYPENAME)
 ///   The 1-character MANGLING for a known TYPENAME of KIND.
 
-STANDARD_TYPE(Structure, A, AutoreleasingUnsafeMutablePointer)
+/// OBJC_INTEROP_STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+///   The 1-character MANGLING for a known TYPENAME of KIND, for a type that's
+///   only available with ObjC interop enabled.
+
+#ifndef OBJC_INTEROP_STANDARD_TYPE
+#define OBJC_INTEROP_STANDARD_TYPE(KIND, MANGLING, TYPENAME) \
+  STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#endif
+
+OBJC_INTEROP_STANDARD_TYPE(Structure, A, AutoreleasingUnsafeMutablePointer)
 STANDARD_TYPE(Structure, a, Array)
 STANDARD_TYPE(Structure, b, Bool)
-STANDARD_TYPE(Structure, c, UnicodeScalar)
 STANDARD_TYPE(Structure, D, Dictionary)
 STANDARD_TYPE(Structure, d, Double)
 STANDARD_TYPE(Structure, f, Float)
@@ -66,3 +74,4 @@ STANDARD_TYPE(Protocol, Z, SignedInteger)
 STANDARD_TYPE(Protocol, z, BinaryInteger)
 
 #undef STANDARD_TYPE
+#undef OBJC_INTEROP_STANDARD_TYPE

stdlib/public/runtime/MetadataLookup.cpp

@@ -718,21 +718,61 @@ _findContextDescriptorInCache(TypeMetadataPrivateState &T,
   return iter->getSecond();
 }
 
+#define DESCRIPTOR_MANGLING_SUFFIX_Structure 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) \
+  $sS ## CHAR ## SUFFIX
+#define DESCRIPTOR_MANGLING(CHAR, SUFFIX) DESCRIPTOR_MANGLING_(CHAR, SUFFIX)
+
+#define STANDARD_TYPE(KIND, MANGLING, TYPENAME) \
+  extern "C" const ContextDescriptor DESCRIPTOR_MANGLING(MANGLING, DESCRIPTOR_MANGLING_SUFFIX(KIND));
+
+#if !SWIFT_OBJC_INTEROP
+# define OBJC_INTEROP_STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#endif
+
+#include "swift/Demangling/StandardTypesMangling.def"
+
 static const ContextDescriptor *
 _findContextDescriptor(Demangle::NodePointer node,
-                           Demangle::Demangler &Dem) {
-  const ContextDescriptor *foundContext = nullptr;
-  auto &T = TypeMetadataRecords.get();
-
-  // If we have a symbolic reference to a context, resolve it immediately.
+                       Demangle::Demangler &Dem) {
   NodePointer symbolicNode = node;
   if (symbolicNode->getKind() == Node::Kind::Type)
     symbolicNode = symbolicNode->getChild(0);
+
+  // If we have a symbolic reference to a context, resolve it immediately.
   if (symbolicNode->getKind() == Node::Kind::TypeSymbolicReference) {
     return cast<TypeContextDescriptor>(
       (const ContextDescriptor *)symbolicNode->getIndex());
   }
 
+  // Fast-path lookup for standard library type references with short manglings.
+  if (symbolicNode->getNumChildren() >= 2
+      && symbolicNode->getChild(0)->getKind() == Node::Kind::Module
+      && symbolicNode->getChild(0)->getText().equals("Swift")
+      && symbolicNode->getChild(1)->getKind() == Node::Kind::Identifier) {
+    auto name = symbolicNode->getChild(1)->getText();
+
+#define STANDARD_TYPE(KIND, MANGLING, TYPENAME) \
+    if (name.equals(#TYPENAME)) { \
+      return &DESCRIPTOR_MANGLING(MANGLING, DESCRIPTOR_MANGLING_SUFFIX(KIND)); \
+    }
+#if !SWIFT_OBJC_INTEROP
+# define OBJC_INTEROP_STANDARD_TYPE(KIND, MANGLING, TYPENAME)
+#endif
+
+#include "swift/Demangling/StandardTypesMangling.def"
+  }
+  
+  const ContextDescriptor *foundContext = nullptr;
+  auto &T = TypeMetadataRecords.get();
+
   // Nothing to resolve if have a generic parameter.
   if (symbolicNode->getKind() == Node::Kind::DependentGenericParamType)
     return nullptr;

test/SILGen/arguments.swift

@@ -25,7 +25,7 @@ func arg_tuple(x: Int, y: Float) {}
 arg_tuple(x: i, y: f)
 
 func arg_deep_tuples(x: Int, y: (Float, UnicodeScalar)) {}
-// CHECK-LABEL: sil hidden [ossa] @$ss15arg_deep_tuples1x1yySi_Sf_ScttF
+// CHECK-LABEL: sil hidden [ossa] @$ss15arg_deep_tuples1x1yySi_Sf_s13UnicodeScalarVttF
 // CHECK: bb0([[X:%[0-9]+]] : $Int, [[Y_0:%[0-9]+]] : $Float, [[Y_1:%[0-9]+]] : $UnicodeScalar):
 
 arg_deep_tuples(x:i, y:(f, c))
@@ -37,7 +37,7 @@ var named_subtuple = (x:f, y:c)
 arg_deep_tuples(x:i, y: named_subtuple)
 
 func arg_deep_tuples_2(x: Int, _: (y: Float, z: UnicodeScalar)) {}
-// CHECK-LABEL: sil hidden [ossa] @$ss17arg_deep_tuples_21x_ySi_Sf1y_Sc1zttF
+// CHECK-LABEL: sil hidden [ossa] @$ss17arg_deep_tuples_21x_ySi_Sf1y_s13UnicodeScalarV1zttF
 // CHECK: bb0([[X:%[0-9]+]] : $Int, [[Y:%[0-9]+]] : $Float, [[Z:%[0-9]+]] : $UnicodeScalar):
 
 arg_deep_tuples_2(x: i, (f, c))