SIL/AST: add some APIs

* `GenericSignature.isEmpty`
* `Builder.emitDestroy`
* `Function.abi`
* `KeyPathInst.substitutionMap`
* `KeyPathInst.hasPattern`

Author: eeckstein

SwiftCompilerSources/Sources/AST/GenericSignature.swift

@@ -33,4 +33,6 @@ public struct GenericSignature: CustomStringConvertible, NoReflectionChildren {
   public func mapTypeIntoContext(_ type: Type) -> Type {
     Type(bridged: bridged.mapTypeIntoContext(type.bridged))
   }
+
+  public var isEmpty: Bool { bridged.impl == nil }
 }

SwiftCompilerSources/Sources/SIL/Builder.swift

@@ -756,3 +756,23 @@ public struct Builder {
     return notifyNew(convertFunction.getAs(ConvertEscapeToNoEscapeInst.self))
   }
 }
+
+
+//===----------------------------------------------------------------------===//
+//                                  Utilities
+//===----------------------------------------------------------------------===//
+
+extension Builder {
+  public func emitDestroy(of value: Value) {
+    if value.type.isTrivial(in: value.parentFunction) {
+      return
+    }
+    if value.parentFunction.hasOwnership {
+      createDestroyValue(operand: value)
+    } else if value.type.isClass {
+      createStrongRelease(operand: value)
+    } else {
+      createReleaseValue(operand: value)
+    }
+  }
+}

SwiftCompilerSources/Sources/SIL/Function.swift

@@ -327,6 +327,20 @@ final public class Function : CustomStringConvertible, HasShortDescription, Hash
     }
   }
 
+  public enum ABILanguage {
+    case C
+    case Swift
+  }
+
+  public var abi: ABILanguage {
+    switch bridged.getSILFunctionLanguage() {
+      case .C:     return .C
+      case .Swift: return .Swift
+      default:
+        fatalError()
+    }
+  }
+
   public enum SourceFileKind {
     case library         /// A normal .swift file.
     case main            /// A .swift file that can have top-level code.

SwiftCompilerSources/Sources/SIL/Instruction.swift

@@ -1111,6 +1111,14 @@ final public class RefTailAddrInst : SingleValueInstruction, UnaryInstruction {
 }
 
 final public class KeyPathInst : SingleValueInstruction {
+  public var substitutionMap: SubstitutionMap {
+    SubstitutionMap(bridged: bridged.KeyPathInst_getSubstitutionMap())
+  }
+
+  public var hasPattern: Bool {
+    bridged.KeyPathInst_hasPattern()
+  }
+
   public override func visitReferencedFunctions(_ cl: (Function) -> ()) {
     var results = BridgedInstruction.KeyPathFunctionResults()
     for componentIdx in 0..<bridged.KeyPathInst_getNumComponents() {

include/swift/SIL/SILBridging.h

@@ -469,6 +469,10 @@ struct BridgedFunction {
     AlwaysInline
   };
 
+  enum class ABILanguage {
+    Swift, C
+  };
+
   enum class ThunkKind {
     IsNotThunk,
     IsThunk,
@@ -530,6 +534,7 @@ struct BridgedFunction {
   BRIDGED_INLINE EffectsKind getEffectAttribute() const;
   BRIDGED_INLINE PerformanceConstraints getPerformanceConstraints() const;
   BRIDGED_INLINE InlineStrategy getInlineStrategy() const;
+  BRIDGED_INLINE ABILanguage getSILFunctionLanguage() const;
   BRIDGED_INLINE SerializedKind getSerializedKind() const;
   BRIDGED_INLINE bool canBeInlinedIntoCaller(SerializedKind) const;
   BRIDGED_INLINE bool hasValidLinkageForFragileRef(SerializedKind) const;
@@ -861,6 +866,8 @@ struct BridgedInstruction {
   BRIDGED_INLINE bool AllocRefInst_isBare() const;
   BRIDGED_INLINE void AllocRefInst_setIsBare() const;
   BRIDGED_INLINE void TermInst_replaceBranchTarget(BridgedBasicBlock from, BridgedBasicBlock to) const;
+  BRIDGED_INLINE BridgedSubstitutionMap KeyPathInst_getSubstitutionMap() const;
+  BRIDGED_INLINE bool KeyPathInst_hasPattern() const;
   BRIDGED_INLINE SwiftInt KeyPathInst_getNumComponents() const;
   BRIDGED_INLINE void KeyPathInst_getReferencedFunctions(SwiftInt componentIdx, KeyPathFunctionResults * _Nonnull results) const;
   BRIDGED_INLINE void GlobalAddrInst_clearToken() const;

include/swift/SIL/SILBridgingImpl.h

@@ -823,6 +823,11 @@ BridgedFunction::InlineStrategy BridgedFunction::getInlineStrategy() const {
   return (InlineStrategy)getFunction()->getInlineStrategy();
 }
 
+BridgedFunction::ABILanguage BridgedFunction::getSILFunctionLanguage() const {
+  auto rep = getFunction()->getLoweredFunctionType()->getRepresentation();
+  return (ABILanguage)swift::getSILFunctionLanguage(rep);
+}
+
 BridgedFunction::ThunkKind BridgedFunction::isThunk() const {
   return (ThunkKind)getFunction()->isThunk();
 }
@@ -1578,6 +1583,14 @@ void BridgedInstruction::TermInst_replaceBranchTarget(BridgedBasicBlock from, Br
                                                 to.unbridged());
 }
 
+BridgedSubstitutionMap BridgedInstruction::KeyPathInst_getSubstitutionMap() const {
+  return getAs<swift::KeyPathInst>()->getSubstitutions();
+}
+
+bool BridgedInstruction::KeyPathInst_hasPattern() const {
+  return getAs<swift::KeyPathInst>()->hasPattern();
+}
+
 SwiftInt BridgedInstruction::KeyPathInst_getNumComponents() const {
   if (swift::KeyPathPattern *pattern = getAs<swift::KeyPathInst>()->getPattern()) {
     return (SwiftInt)pattern->getComponents().size();

lib/SIL/Utils/SILBridging.cpp

@@ -190,6 +190,9 @@ static_assert((int)BridgedFunction::InlineStrategy::InlineDefault == (int)swift:
 static_assert((int)BridgedFunction::InlineStrategy::NoInline == (int)swift::NoInline);
 static_assert((int)BridgedFunction::InlineStrategy::AlwaysInline == (int)swift::AlwaysInline);
 
+static_assert((int)BridgedFunction::ABILanguage::Swift == (int)swift::SILFunctionLanguage::Swift);
+static_assert((int)BridgedFunction::ABILanguage::C == (int)swift::SILFunctionLanguage::C);
+
 static_assert((int)BridgedFunction::ThunkKind::IsNotThunk == (int)swift::IsNotThunk);
 static_assert((int)BridgedFunction::ThunkKind::IsThunk == (int)swift::IsThunk);
 static_assert((int)BridgedFunction::ThunkKind::IsReabstractionThunk == (int)swift::IsReabstractionThunk);