Merge pull request #23923 from slavapestov/noescape-diagnostics-5.1

Redo diagnostics for escaping captures and non-escaping parameter call restriction [5.1]

Author: slavapestov

include/swift/AST/DiagnosticsParse.def

@@ -1379,21 +1379,6 @@ WARNING(attr_availability_nonspecific_platform_unexpected_version,none,
       "unexpected version number in '%0' attribute for non-specific platform "
       "'*'", (StringRef))
 
-// autoclosure
-ERROR(attr_autoclosure_expected_r_paren,PointsToFirstBadToken,
-      "expected ')' in @autoclosure", ())
-ERROR(attr_noescape_conflicts_escaping_autoclosure,none,
-      "@noescape conflicts with @autoclosure(escaping)", ())
-ERROR(attr_noescape_implied_by_autoclosure,none,
-      "@noescape is implied by @autoclosure and should not be "
-      "redundantly specified", ())
-ERROR(attr_autoclosure_escaping_deprecated,none,
-      "@autoclosure(escaping) has been removed; use @autoclosure @escaping instead",
-      ())
-ERROR(attr_noescape_deprecated,none,
-      "@noescape is the default and has been removed",
-      ())
-
 // convention
 ERROR(convention_attribute_expected_lparen,none,
       "expected '(' after 'convention' attribute", ())

include/swift/AST/DiagnosticsSIL.def

@@ -116,6 +116,33 @@ ERROR(unsupported_c_function_pointer_conversion,none,
 ERROR(objc_selector_malformed,none,"the type ObjectiveC.Selector is malformed",
       ())
 
+// Invalid escaping capture diagnostics.
+ERROR(escaping_inout_capture,none,
+      "escaping closure captures 'inout' parameter %0", (Identifier))
+NOTE(inout_param_defined_here,none,
+     "parameter %0 is declared 'inout'", (Identifier))
+ERROR(escaping_mutable_self_capture,none,
+      "escaping closure captures mutating 'self' parameter", ())
+
+ERROR(escaping_noescape_param_capture,none,
+      "escaping closure captures non-escaping parameter %0", (Identifier))
+NOTE(noescape_param_defined_here,none,
+     "parameter %0 is implicitly non-escaping", (Identifier))
+
+ERROR(escaping_noescape_var_capture,none,
+      "escaping closure captures non-escaping value", ())
+
+NOTE(value_captured_here,none,"captured here", ())
+
+NOTE(value_captured_transitively,none,
+     "captured indirectly by this call", ())
+
+ERROR(err_noescape_param_call,none,
+      "passing a %select{|closure which captures a }1non-escaping function "
+      "parameter %0 to a call to a non-escaping function parameter can allow "
+      "re-entrant modification of a variable",
+      (DeclName, unsigned))
+
 // Definite initialization diagnostics.
 NOTE(variable_defined_here,none,
      "%select{variable|constant}0 defined here", (bool))

include/swift/AST/DiagnosticsSema.def

@@ -293,11 +293,6 @@ ERROR(incorrect_explicit_closure_result,none,
       "declared closure result %0 is incompatible with contextual type %1",
       (Type, Type))
 
-ERROR(err_noescape_param_call,none,
-      "passing a %select{|closure which captures a }1non-escaping function "
-      "parameter %0 to a call to a non-escaping function parameter can allow "
-      "re-entrant modification of a variable",
-      (DeclName, unsigned))
 ERROR(cannot_call_function_value,none,
       "cannot invoke value of function type with argument list '%0'",
       (StringRef))
@@ -2905,21 +2900,6 @@ NOTE(transitive_capture_through_here,none,
      "%0, declared here, captures %1",
      (Identifier, Identifier))
 
-ERROR(closure_implicit_capture_without_noescape,none,
-      "escaping closures can only capture inout parameters explicitly by value",
-      ())
-ERROR(closure_implicit_capture_mutating_self,none,
-      "escaping closure cannot capture a mutating self parameter",
-      ())
-NOTE(create_mutating_copy_or_capture_self,none,
-     "create a mutating copy of self, or explicitly capture self for immutability",
-     ())
-ERROR(nested_function_with_implicit_capture_argument,none,
-      "nested function with %select{an |}0implicitly captured inout "
-      "parameter%select{|s}0 can only be used as a non-escaping argument", (bool))
-ERROR(nested_function_escaping_inout_capture,none,
-      "nested function cannot capture inout parameter and escape", ())
-
 WARNING(recursive_accessor_reference,none,
         "attempting to %select{access|modify}1 %0 within its own "
         "%select{getter|setter}1", (Identifier, bool))
@@ -3044,19 +3024,10 @@ WARNING(debug_description_in_string_interpolation_segment,none,
 NOTE(silence_debug_description_in_interpolation_segment_call,none,
      "use 'String(describing:)' to silence this warning", ())
 
-ERROR(invalid_noescape_use,none,
-      "non-escaping %select{value|parameter}1 %0 may only be called",
-      (Identifier, bool))
 NOTE(noescape_parameter,none,
     "parameter %0 is implicitly non-escaping",
      (Identifier))
 
-ERROR(closure_noescape_use,none,
-      "closure use of non-escaping parameter %0 may allow it to escape",
-      (Identifier))
-ERROR(decl_closure_noescape_use,none,
-      "declaration closing over non-escaping parameter %0 may allow it to escape",
-      (Identifier))
 ERROR(passing_noescape_to_escaping,none,
       "passing non-escaping parameter %0 to function expecting an @escaping closure",
       (Identifier))
@@ -3529,8 +3500,6 @@ NOTE(overridden_required_initializer_here,none,
 // Functions
 ERROR(attribute_requires_function_type,none,
       "@%0 attribute only applies to function types", (StringRef))
-ERROR(attribute_not_supported,none,
-      "this attribute is not supported", ())
 ERROR(unsupported_convention,none,
       "convention '%0' not supported", (StringRef))
 ERROR(unreferenced_generic_parameter,none,

include/swift/AST/Types.h

@@ -622,10 +622,14 @@ class alignas(1 << TypeAlignInBits) TypeBase {
     return getRecursiveProperties().isLValue();
   }
 
-  /// Is a type with these properties materializable: that is, is it a
-  /// first-class value type?
+  /// Is this a first-class value type, meaning it is not an InOutType or a
+  /// tuple type containing an InOutType?
   bool isMaterializable();
 
+  /// Is this a non-escaping type, that is, a non-escaping function type or a
+  /// tuple type containing a non-escaping type?
+  bool isNoEscape() const;
+
   /// Determine whether the type is dependent on DynamicSelf.
   bool hasDynamicSelfType() const {
     return getRecursiveProperties().hasDynamicSelf();

include/swift/Migrator/FixitFilter.h

@@ -127,8 +127,6 @@ struct FixitFilter {
         Info.ID == diag::where_inside_brackets.ID ||
         Info.ID == diag::selector_construction_suggest.ID ||
         Info.ID == diag::selector_literal_deprecated_suggest.ID ||
-        Info.ID == diag::attr_noescape_deprecated.ID ||
-        Info.ID == diag::attr_autoclosure_escaping_deprecated.ID ||
         Info.ID == diag::attr_warn_unused_result_removed.ID ||
         Info.ID == diag::any_as_anyobject_fixit.ID ||
         Info.ID == diag::deprecated_protocol_composition.ID ||

include/swift/SILOptimizer/PassManager/Passes.def

@@ -134,6 +134,8 @@ PASS(Devirtualizer, "devirtualizer",
      "Indirect Call Devirtualization")
 PASS(DiagnoseInfiniteRecursion, "diagnose-infinite-recursion",
      "Diagnose Infinitely-Recursive Code")
+PASS(DiagnoseInvalidEscapingCaptures, "diagnose-invalid-escaping-captures",
+     "Diagnose Invalid Escaping Captures")
 PASS(DiagnoseStaticExclusivity, "diagnose-static-exclusivity",
      "Static Enforcement of Law of Exclusivity")
 PASS(DiagnoseUnreachable, "diagnose-unreachable",

lib/AST/Type.cpp

@@ -3079,6 +3079,24 @@ const DependentMemberType *TypeBase::findUnresolvedDependentMemberType() {
   return unresolvedDepMemTy;
 }
 
+bool TypeBase::isNoEscape() const {
+  auto type = getCanonicalType();
+
+  if (auto silFuncTy = dyn_cast<SILFunctionType>(type))
+    return silFuncTy->isNoEscape();
+
+  if (auto funcTy = dyn_cast<FunctionType>(type))
+    return funcTy->isNoEscape();
+
+  if (auto tupleTy = dyn_cast<TupleType>(type)) {
+    for (auto eltTy : tupleTy.getElementTypes())
+      if (eltTy->isNoEscape())
+        return true;
+  }
+
+  return false;
+}
+
 static Type getConcreteTypeForSuperclassTraversing(Type t) {
   if (t->isExistentialType()) {
     return t->getExistentialLayout().getSuperclass();

lib/Parse/ParseDecl.cpp

@@ -1940,31 +1940,10 @@ bool Parser::parseTypeAttribute(TypeAttributes &Attributes, bool justChecking) {
   StringRef Text = Tok.getText();
   SourceLoc Loc = consumeToken();
 
-  bool isAutoclosureEscaping = false;
-  SourceRange autoclosureEscapingParenRange;
   StringRef conventionName;
   StringRef witnessMethodProtocol;
 
-  // Handle @autoclosure(escaping)
-  if (attr == TAK_autoclosure) {
-    // We need to do a bit of lookahead here to make sure we parse a (weird)
-    // type like: "@autoclosure (escaping) -> Int" correctly (escaping is the
-    // name of a type here).  We also want to support the case where the
-    // function type coming up is a typealias, e.g. "@autoclosure (escaping) T".
-    if (Tok.is(tok::l_paren) && peekToken().getText() == "escaping") {
-      Parser::BacktrackingScope Backtrack(*this);
-      consumeToken(tok::l_paren);
-      consumeToken(tok::identifier);
-      isAutoclosureEscaping =
-        Tok.is(tok::r_paren) && peekToken().isNot(tok::arrow);
-    }
-
-    if (isAutoclosureEscaping) {
-      autoclosureEscapingParenRange.Start = consumeToken(tok::l_paren);
-      consumeToken(tok::identifier);
-      autoclosureEscapingParenRange.End = consumeToken(tok::r_paren);
-    }
-  } else if (attr == TAK_convention) {
+  if (attr == TAK_convention) {
     SourceLoc LPLoc;
     if (!consumeIfNotAtStartOfLine(tok::l_paren)) {
       if (!justChecking)
@@ -2027,48 +2006,10 @@ bool Parser::parseTypeAttribute(TypeAttributes &Attributes, bool justChecking) {
   switch (attr) {
   default: break;
   case TAK_autoclosure:
-    // Handle @autoclosure(escaping)
-    if (isAutoclosureEscaping) {
-      // @noescape @autoclosure(escaping) makes no sense.
-      if (Attributes.has(TAK_noescape)) {
-        diagnose(Loc, diag::attr_noescape_conflicts_escaping_autoclosure);
-      } else {
-        diagnose(Loc, diag::attr_autoclosure_escaping_deprecated)
-            .fixItReplace(autoclosureEscapingParenRange, " @escaping ");
-      }
-      Attributes.setAttr(TAK_escaping, Loc);
-    } else if (Attributes.has(TAK_noescape) && !isInSILMode()) {
-      diagnose(Loc, diag::attr_noescape_implied_by_autoclosure);
-    }
-    break;
-
-  case TAK_noescape:
-    // You can't specify @noescape and @escaping together.
-    if (Attributes.has(TAK_escaping)) {
-      diagnose(Loc, diag::attr_escaping_conflicts_noescape);
-      return false;
-    }
-
-    // @noescape after @autoclosure is redundant.
-    if (Attributes.has(TAK_autoclosure) && !isInSILMode()) {
-      diagnose(Loc, diag::attr_noescape_implied_by_autoclosure);
-    }
-
-    // @noescape is deprecated and no longer used
-    // In SIL, the polarity of @escaping is reversed.
-    // @escaping is the default and @noescape is explicit.
-    if (!isInSILMode()) {
-      diagnose(Loc, diag::attr_noescape_deprecated)
-        .fixItRemove({Attributes.AtLoc, Loc});
-    }
-    break;
   case TAK_escaping:
-    // You can't specify @noescape and @escaping together.
-    if (Attributes.has(TAK_noescape)) {
-      diagnose(Loc, diag::attr_escaping_conflicts_noescape);
-      return false;
-    }
+  case TAK_noescape:
     break;
+
   case TAK_out:
   case TAK_in:
   case TAK_owned:

lib/SILOptimizer/Mandatory/CMakeLists.txt

@@ -7,6 +7,7 @@ silopt_register_sources(
   DIMemoryUseCollector.cpp
   DataflowDiagnostics.cpp
   DiagnoseInfiniteRecursion.cpp
+  DiagnoseInvalidEscapingCaptures.cpp
   DiagnoseStaticExclusivity.cpp
   DiagnoseUnreachable.cpp
   GuaranteedARCOpts.cpp