Merge pull request swiftlang#209 from swiftwasm/master

[pull] swiftwasm from master

Author: kateinoigakukun

benchmark/CMakeLists.txt

@@ -62,6 +62,7 @@ set(SWIFT_BENCH_MODULES
     single-source/Combos
     single-source/DataBenchmarks
     single-source/DeadArray
+    single-source/DevirtualizeProtocolComposition
     single-source/DictOfArraysToArrayOfDicts
     single-source/DictTest
     single-source/DictTest2

benchmark/single-source/DevirtualizeProtocolComposition.swift

@@ -0,0 +1,45 @@
+//===--- DevirtualizeProtocolComposition.swift -------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2019 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
+//
+//===----------------------------------------------------------------------===//
+
+import TestsUtils
+
+public let DevirtualizeProtocolComposition = [
+  BenchmarkInfo(name: "DevirtualizeProtocolComposition", runFunction: run_DevirtualizeProtocolComposition, tags: [.validation, .api]),
+]
+
+protocol Pingable { func ping() -> Int; func pong() -> Int}
+
+public class Game<T> {
+  func length() -> Int { return 10 }
+}
+
+public class PingPong: Game<String> { }
+
+extension PingPong : Pingable {
+  func ping() -> Int { return 1 }
+  func pong() -> Int { return 2 }
+}
+
+func playGame<T>(_ x: Game<T> & Pingable) -> Int {
+  var sum = 0
+  for _ in 0..<x.length() {
+    sum += x.ping() + x.pong()
+  }
+  return sum
+}
+
+@inline(never)
+public func run_DevirtualizeProtocolComposition(N: Int) {
+  for _ in 0..<N * 20_000 {
+    blackHole(playGame(PingPong()))
+  }
+}

benchmark/utils/main.swift

@@ -50,6 +50,7 @@ import Codable
 import Combos
 import DataBenchmarks
 import DeadArray
+import DevirtualizeProtocolComposition
 import DictOfArraysToArrayOfDicts
 import DictTest
 import DictTest2
@@ -231,6 +232,7 @@ registerBenchmark(Combos)
 registerBenchmark(ClassArrayGetter)
 registerBenchmark(DataBenchmarks)
 registerBenchmark(DeadArray)
+registerBenchmark(DevirtualizeProtocolComposition)
 registerBenchmark(DictOfArraysToArrayOfDicts)
 registerBenchmark(Dictionary)
 registerBenchmark(Dictionary2)

docs/OptimizationTips.rst

@@ -544,6 +544,38 @@ protocols as class-only protocols to get better runtime performance.
 
 .. https://developer.apple.com/library/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Protocols.html
 
+The Cost of Let/Var when Captured by Escaping Closures
+======================================================
+
+While one may think that the distinction in between let/var is just
+about language semantics, there are also performance
+considerations. Remember that any time one creates a binding for a
+closure, one is forcing the compiler to emit an escaping closure,
+e.x.:
+
+::
+
+  let f: () -> () = { ... } // Escaping closure
+  // Contrasted with:
+  ({ ... })() // Non Escaping closure
+  x.map { ... } // Non Escaping closure
+
+When a var is captured by an escaping closure, the compiler must
+allocate a heap box to store the var so that both the closure
+creator/closure can read/write to the value. This even includes
+situations where the underlying type of the captured binding is
+trivial! In contrast, when captured a `let` is captured by value. As
+such, the compiler stores a copy of the value directly into the
+closure's storage without needing a box.
+
+Advice: Pass var as an `inout` if closure not actually escaping
+---------------------------------------------------------------
+
+If one is using an escaping closure for expressivity purposes, but is
+actually using a closure locally, pass vars as inout parameters
+instead of by using captures. The inout will ensure that a heap box is
+not allocated for the variables and avoid any retain/release traffic
+from the heap box being passed around.
 
 Unsupported Optimization Attributes
 ===================================

docs/TypeChecker.rst

@@ -985,4 +985,3 @@ The things in the queue yet to be ported are:
 
   - Missing explicit ``Self.`` and ``self.``
   - Logic related to overload candidate ranking (``CalleeCandidateInfo``)
-  - ``diagnoseParameterErrors``

include/swift/AST/DiagnosticsSIL.def

@@ -447,12 +447,12 @@ ERROR(constexpr_imported_func_not_onone, none, "imported constant evaluable "
 
 ERROR(non_physical_addressof,none,
       "addressof only works with purely physical lvalues; "
-      "use `withUnsafePointer` or `withUnsafeBytes` unless you're implementing "
-      "`withUnsafePointer` or `withUnsafeBytes`", ())
+      "use 'withUnsafePointer' or 'withUnsafeBytes' unless you're implementing "
+      "'withUnsafePointer' or 'withUnsafeBytes'", ())
 ERROR(non_borrowed_indirect_addressof,none,
       "addressof only works with borrowable in-memory rvalues; "
-      "use `withUnsafePointer` or `withUnsafeBytes` unless you're implementing "
-      "`withUnsafePointer` or `withUnsafeBytes`", ())
+      "use 'withUnsafePointer' or 'withUnsafeBytes' unless you're implementing "
+      "'withUnsafePointer' or 'withUnsafeBytes'", ())
 
 REMARK(opt_remark_passed, none, "%0", (StringRef))
 REMARK(opt_remark_missed, none, "%0", (StringRef))

include/swift/AST/DiagnosticsSema.def

@@ -1133,6 +1133,9 @@ ERROR(argument_out_of_order_unnamed_named,none,
 ERROR(argument_out_of_order_unnamed_unnamed,none,
       "unnamed argument #%0 must precede unnamed argument #%1",
       (unsigned, unsigned))
+ERROR(argument_out_of_order_binary_op,none,
+      "operator argument #%0 must precede operator argument #%1",
+      (unsigned, unsigned))
 NOTE(candidate_expected_different_labels,none,
      "incorrect labels for candidate (have: '%0', expected: '%1')",
      (StringRef, StringRef))
@@ -4843,10 +4846,10 @@ ERROR(property_wrapper_type_not_usable_from_inline,none,
       "must be '@usableFromInline' or public",
       (bool, bool))
 WARNING(property_wrapper_wrapperValue,none,
-        "property wrapper's `wrapperValue` property should be renamed to "
+        "property wrapper's 'wrapperValue' property should be renamed to "
         "'projectedValue'; use of 'wrapperValue' is deprecated", ())
 WARNING(property_wrapper_init_initialValue,none,
-        "property wrapper's `init(initialValue:)` should be renamed "
+        "property wrapper's 'init(initialValue:)' should be renamed "
         "to 'init(wrappedValue:)'; use of 'init(initialValue:)' is deprecated",
         ())
 ERROR(property_wrapper_projection_value_missing,none,

include/swift/AST/IRGenOptions.h

@@ -262,7 +262,7 @@ class IRGenOptions {
         EnableAnonymousContextMangledNames(false), ForcePublicLinkage(false),
         LazyInitializeClassMetadata(false),
         LazyInitializeProtocolConformances(false), DisableLegacyTypeInfo(false),
-        PrespecializeGenericMetadata(true), UseIncrementalLLVMCodeGen(true),
+        PrespecializeGenericMetadata(false), UseIncrementalLLVMCodeGen(true),
         UseSwiftCall(false), GenerateProfile(false),
         EnableDynamicReplacementChaining(false),
         DisableRoundTripDebugTypes(false), DisableDebuggerShadowCopies(false),

include/swift/AST/SourceFile.h

@@ -257,12 +257,6 @@ class SourceFile final : public FileUnit {
 
   bool isImportedImplementationOnly(const ModuleDecl *module) const;
 
-  /// This is a hack for 'main' file parsing and the integrated REPL.
-  ///
-  /// FIXME: Refactor main file parsing to not pump the parser incrementally.
-  /// FIXME: Remove the integrated REPL.
-  void clearLookupCache();
-
   void cacheVisibleDecls(SmallVectorImpl<ValueDecl *> &&globals) const;
   const SmallVectorImpl<ValueDecl *> &getCachedVisibleDecls() const;
 

include/swift/AST/Types.h

@@ -2780,7 +2780,8 @@ class AnyFunctionType : public TypeBase {
                    Identifier l = Identifier(),
                    ParameterTypeFlags f = ParameterTypeFlags())
         : Ty(t), Label(l), Flags(f) {
-      assert(!t || !t->is<InOutType>() && "set flags instead");
+      assert(t && "param type must be non-null");
+      assert(!t->is<InOutType>() && "set flags instead");
     }
 
   private: