SwiftCompilerSources: consider indirect error results in Function.numArguments

Author: eeckstein

SwiftCompilerSources/Sources/SIL/Function.swift

@@ -55,9 +55,9 @@ final public class Function : CustomStringConvertible, HasShortDescription, Hash
     blocks.reversed().lazy.flatMap { $0.instructions.reversed() }
   }
 
-  /// The number of indirect result arguments.
   public var numIndirectResultArguments: Int { bridged.getNumIndirectFormalResults() }
-  
+  public var hasIndirectErrorArgument: Bool { bridged.hasIndirectErrorResult() }
+
   /// The number of arguments which correspond to parameters (and not to indirect results).
   public var numParameterArguments: Int { bridged.getNumParameters() }
 
@@ -66,7 +66,9 @@ final public class Function : CustomStringConvertible, HasShortDescription, Hash
   /// This is the sum of indirect result arguments and parameter arguments.
   /// If the function is a definition (i.e. it has at least an entry block), this is the
   /// number of arguments of the function's entry block.
-  public var numArguments: Int { numIndirectResultArguments + numParameterArguments }
+  public var numArguments: Int {
+    numIndirectResultArguments + (hasIndirectErrorArgument ? 1 : 0) + numParameterArguments
+  }
 
   public var hasSelfArgument: Bool {
     bridged.getSelfArgumentIndex() >= 0

include/swift/AST/Types.h

@@ -4785,6 +4785,9 @@ class SILFunctionType final
   unsigned getNumPackResults() const {
     return isCoroutine() ? 0 : NumPackResults;
   }
+  bool hasIndirectErrorResult() const {
+    return hasErrorResult() && getErrorResult().isFormalIndirect();
+  }
 
   struct IndirectFormalResultFilter {
     bool operator()(SILResultInfo result) const {

include/swift/SIL/SILBridging.h

@@ -295,6 +295,7 @@ struct BridgedFunction {
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE OptionalBridgedBasicBlock getFirstBlock() const;
   SWIFT_IMPORT_UNSAFE BRIDGED_INLINE OptionalBridgedBasicBlock getLastBlock() const;
   BRIDGED_INLINE SwiftInt getNumIndirectFormalResults() const;
+  BRIDGED_INLINE bool hasIndirectErrorResult() const;
   BRIDGED_INLINE SwiftInt getNumParameters() const;
   BRIDGED_INLINE SwiftInt getSelfArgumentIndex() const;
   BRIDGED_INLINE SwiftInt getNumSILArguments() const;

include/swift/SIL/SILBridgingImpl.h

@@ -413,6 +413,10 @@ SwiftInt BridgedFunction::getNumIndirectFormalResults() const {
   return (SwiftInt)getFunction()->getLoweredFunctionType()->getNumIndirectFormalResults();
 }
 
+bool BridgedFunction::hasIndirectErrorResult() const {
+  return (SwiftInt)getFunction()->getLoweredFunctionType()->hasIndirectErrorResult();
+}
+
 SwiftInt BridgedFunction::getNumParameters() const {
   return (SwiftInt)getFunction()->getLoweredFunctionType()->getNumParameters();
 }