[NFC] Rename swift_runtime_unreachable to swift_unreachable and make it use LLVM's support when available.

include/swift/ABI/Metadata.h

@@ -38,7 +38,7 @@
 #include "swift/Basic/RelativePointer.h"
 #include "swift/Demangling/Demangle.h"
 #include "swift/Demangling/ManglingMacros.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include "../../../stdlib/public/SwiftShims/HeapObject.h"
 #if SWIFT_OBJC_INTEROP
 #include <objc/runtime.h>
@@ -4664,7 +4664,7 @@ int32_t TargetTypeContextDescriptor<Runtime>::getGenericArgumentOffset() const {
     return llvm::cast<TargetStructDescriptor<Runtime>>(this)
         ->getGenericArgumentOffset();
   default:
-    swift_runtime_unreachable("Not a type context descriptor.");
+    swift_unreachable("Not a type context descriptor.");
   }
 }
 
@@ -4682,7 +4682,7 @@ TargetTypeContextDescriptor<Runtime>::getFullGenericContextHeader() const {
     return llvm::cast<TargetStructDescriptor<Runtime>>(this)
         ->getFullGenericContextHeader();
   default:
-    swift_runtime_unreachable("Not a type context descriptor.");
+    swift_unreachable("Not a type context descriptor.");
   }
 }
 
@@ -4699,7 +4699,7 @@ TargetTypeContextDescriptor<Runtime>::getGenericParams() const {
   case ContextDescriptorKind::OpaqueType:
     return llvm::cast<TargetOpaqueTypeDescriptor<Runtime>>(this)->getGenericParams();
   default:
-    swift_runtime_unreachable("Not a type context descriptor.");
+    swift_unreachable("Not a type context descriptor.");
   }
 }
 
@@ -4717,7 +4717,7 @@ TargetTypeContextDescriptor<Runtime>::getForeignMetadataInitialization() const {
     return llvm::cast<TargetStructDescriptor<Runtime>>(this)
         ->getForeignMetadataInitialization();
   default:
-    swift_runtime_unreachable("Not a type context descriptor.");
+    swift_unreachable("Not a type context descriptor.");
   }
 }
 
@@ -4735,7 +4735,7 @@ TargetTypeContextDescriptor<Runtime>::getSingletonMetadataInitialization() const
     return llvm::cast<TargetClassDescriptor<Runtime>>(this)
         ->getSingletonMetadataInitialization();
   default:
-    swift_runtime_unreachable("Not a enum, struct or class type descriptor.");
+    swift_unreachable("Not a enum, struct or class type descriptor.");
   }
 }
 
@@ -4753,7 +4753,7 @@ TargetTypeContextDescriptor<Runtime>::getCanonicicalMetadataPrespecializations()
     return llvm::cast<TargetClassDescriptor<Runtime>>(this)
         ->getCanonicicalMetadataPrespecializations();
   default:
-    swift_runtime_unreachable("Not a type context descriptor.");
+    swift_unreachable("Not a type context descriptor.");
   }
 }
 

include/swift/ABI/ProtocolDispatchStrategy.h

@@ -19,7 +19,7 @@
 #ifndef SWIFT_ABI_PROTOCOLDISPATCHSTRATEGY_H
 #define SWIFT_ABI_PROTOCOLDISPATCHSTRATEGY_H
 
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 namespace swift {
 
@@ -46,7 +46,7 @@ inline bool protocolRequiresWitnessTable(ProtocolDispatchStrategy strategy) {
     return true;
   }
 
-  swift_runtime_unreachable("Unhandled ProtocolDispatchStrategy in switch.");
+  swift_unreachable("Unhandled ProtocolDispatchStrategy in switch.");
 }
 
 }

include/swift/Basic/Unreachable.h

@@ -1,4 +1,4 @@
-//===--- Unreachable.h - Implements swift_runtime_unreachable ---*- C++ -*-===//
+//===--- Unreachable.h - Implements swift_unreachable ---*- C++ -*-===//
 //
 // This source file is part of the Swift.org open source project
 //
@@ -10,13 +10,25 @@
 //
 //===----------------------------------------------------------------------===//
 //
-//  This file defines swift_runtime_unreachable, an LLVM-independent
-//  implementation of llvm_unreachable.
+//  This file defines swift_unreachable, which provides the
+//  functionality of llvm_unreachable without necessarily depending on
+//  the LLVM support libraries.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef SWIFT_RUNTIME_UNREACHABLE_H
-#define SWIFT_RUNTIME_UNREACHABLE_H
+#ifndef SWIFT_BASIC_UNREACHABLE_H
+#define SWIFT_BASIC_UNREACHABLE_H
+
+#ifdef SWIFT_LLVM_SUPPORT_IS_AVAILABLE
+
+// The implementation when LLVM is available.
+
+#include "llvm/Support/ErrorHandling.h"
+#define swift_unreachable llvm_unreachable
+
+#else
+
+// The implementation when LLVM is not available.
 
 #include <assert.h>
 #include <stdlib.h>
@@ -24,10 +36,12 @@
 #include "swift/Runtime/Config.h"
 
 SWIFT_RUNTIME_ATTRIBUTE_NORETURN
-inline static void swift_runtime_unreachable(const char *msg) {
+inline static void swift_unreachable(const char *msg) {
   assert(false && msg);
   (void)msg;
   abort();
 }
 
-#endif // SWIFT_RUNTIME_UNREACHABLE_H
+#endif
+
+#endif

include/swift/Demangling/TypeDecoder.h

@@ -24,7 +24,7 @@
 #include "swift/Demangling/Demangler.h"
 #include "swift/Demangling/NamespaceMacros.h"
 #include "swift/Runtime/Portability.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include "swift/Strings.h"
 #include "llvm/ADT/ArrayRef.h"
 #include <vector>

include/swift/Reflection/ReflectionContext.h

@@ -33,7 +33,7 @@
 #include "swift/Reflection/TypeLowering.h"
 #include "swift/Reflection/TypeRef.h"
 #include "swift/Reflection/TypeRefBuilder.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 #include <set>
 #include <unordered_map>
@@ -1302,7 +1302,7 @@ private:
       return true;
     }
 
-    swift_runtime_unreachable("Unhandled MetadataSourceKind in switch.");
+    swift_unreachable("Unhandled MetadataSourceKind in switch.");
   }
 
   /// Read metadata for a captured generic type from a closure context.

include/swift/Reflection/TypeRef.h

@@ -22,7 +22,7 @@
 #include "llvm/Support/Casting.h"
 #include "swift/ABI/MetadataValues.h"
 #include "swift/Remote/MetadataReader.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 namespace swift {
 namespace reflection {
@@ -856,7 +856,7 @@ public:
 #include "swift/Reflection/TypeRefs.def"
     }
 
-    swift_runtime_unreachable("Unhandled TypeRefKind in switch.");
+    swift_unreachable("Unhandled TypeRefKind in switch.");
   }
 };
 

include/swift/Remote/MetadataReader.h

@@ -28,7 +28,7 @@
 #include "swift/ABI/TypeIdentity.h"
 #include "swift/Runtime/ExistentialContainer.h"
 #include "swift/Runtime/HeapObject.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 #include <vector>
 #include <unordered_map>
@@ -923,7 +923,7 @@ public:
     }
     }
 
-    swift_runtime_unreachable("Unhandled MetadataKind in switch");
+    swift_unreachable("Unhandled MetadataKind in switch");
   }
 
   TypeLookupErrorOr<typename BuilderType::BuiltType>
@@ -1295,7 +1295,7 @@ public:
     }
     }
 
-    swift_runtime_unreachable("Unhandled IsaEncodingKind in switch.");
+    swift_unreachable("Unhandled IsaEncodingKind in switch.");
   }
 
   /// Read the offset of the generic parameters of a class from the nominal

include/swift/Runtime/Debug.h

@@ -18,7 +18,7 @@
 #define SWIFT_RUNTIME_DEBUG_HELPERS_H
 
 #include "swift/Runtime/Config.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include <atomic>
 #include <cstdarg>
 #include <functional>
@@ -79,7 +79,7 @@ static inline void crash(const char *message) {
   CRSetCrashLogMessage(message);
 
   SWIFT_RUNTIME_BUILTIN_TRAP;
-  swift_runtime_unreachable("Expected compiler to crash.");
+  swift_unreachable("Expected compiler to crash.");
 }
 
 // swift::fatalError() halts with a crash log message, 

lib/AST/CMakeLists.txt

@@ -9,6 +9,8 @@ else()
   )
 endif()
 
+set_swift_llvm_is_available()
+
 add_swift_host_library(swiftAST STATIC
   AbstractSourceFileDepGraphFactory.cpp
   AccessRequests.cpp

lib/ASTSectionImporter/CMakeLists.txt

@@ -1,3 +1,5 @@
+set_swift_llvm_is_available()
+
 add_swift_host_library(swiftASTSectionImporter STATIC
   ASTSectionImporter.cpp
   LLVM_LINK_COMPONENTS core)

lib/ClangImporter/CMakeLists.txt

@@ -4,6 +4,8 @@ set(SWIFT_GYB_FLAGS
 add_gyb_target(generated_sorted_cf_database
     SortedCFDatabase.def.gyb)
 
+set_swift_llvm_is_available()
+
 add_swift_host_library(swiftClangImporter STATIC
   CFTypeInfo.cpp
   ClangAdapter.cpp

lib/Driver/CMakeLists.txt

@@ -1,3 +1,5 @@
+set_swift_llvm_is_available()
+
 set(swiftDriver_sources
   Action.cpp
   Compilation.cpp

lib/Frontend/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftFrontend STATIC
   ArgsToFrontendInputsConverter.cpp
   ArgsToFrontendOptionsConverter.cpp

lib/FrontendTool/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftFrontendTool STATIC
   FrontendTool.cpp
   ImportedModules.cpp

lib/IDE/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftIDE STATIC
   CodeCompletion.cpp
   CodeCompletionCache.cpp

lib/IRGen/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftIRGen STATIC
   AllocStackHoisting.cpp
   ClassLayout.cpp

lib/LLVMPasses/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftLLVMPasses STATIC
   LLVMSwiftAA.cpp
   LLVMSwiftRCIdentity.cpp

lib/Migrator/CMakeLists.txt

@@ -47,6 +47,8 @@ swift_install_in_component(FILES ${datafiles}
                            DESTINATION "lib/swift/migrator"
                            COMPONENT compiler)
 
+set_swift_llvm_is_available()
+
 add_swift_host_library(swiftMigrator STATIC
   APIDiffMigratorPass.cpp
   EditorAdapter.cpp

lib/Parse/CMakeLists.txt

@@ -1,3 +1,5 @@
+set_swift_llvm_is_available()
+
 if(CMAKE_HOST_SYSTEM_NAME STREQUAL Windows)
   set(SWIFT_GYB_FLAGS --line-directive "^\"#line %(line)d \\\"%(file)s\\\"^\"")
 else()

lib/PrintAsObjC/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftPrintAsObjC STATIC
   DeclAndTypePrinter.cpp
   ModuleContentsWriter.cpp

lib/SIL/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSIL STATIC
   SIL.cpp)
 target_link_libraries(swiftSIL PUBLIC

lib/SILGen/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSILGen STATIC
   ArgumentSource.cpp
   Cleanup.cpp

lib/SILOptimizer/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSILOptimizer STATIC
   SILOptimizer.cpp)
 target_link_libraries(swiftSILOptimizer PRIVATE

lib/Sema/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSema STATIC
   BuilderTransform.cpp
   CSApply.cpp

lib/Serialization/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSerialization STATIC
   Deserialization.cpp
   DeserializeSIL.cpp

lib/SyntaxParse/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftSyntaxParse STATIC
   RawSyntaxTokenCache.cpp
   SyntaxTreeCreator.cpp)

lib/TBDGen/CMakeLists.txt

@@ -1,3 +1,4 @@
+set_swift_llvm_is_available()
 add_swift_host_library(swiftTBDGen STATIC
   TBDGen.cpp
   TBDGenRequests.cpp

stdlib/public/Reflection/TypeLowering.cpp

@@ -23,7 +23,7 @@
 #include "swift/Reflection/TypeLowering.h"
 #include "swift/Reflection/TypeRef.h"
 #include "swift/Reflection/TypeRefBuilder.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 #ifdef DEBUG_TYPE_LOWERING
   #define DEBUG_LOG(expr) expr;
@@ -212,7 +212,7 @@ public:
     }
     }
 
-    swift_runtime_unreachable("Bad TypeInfo kind");
+    swift_unreachable("Bad TypeInfo kind");
   }
 };
 
@@ -2007,7 +2007,7 @@ public:
       return nullptr;
     }
 
-    swift_runtime_unreachable("Unhandled FieldDescriptorKind in switch.");
+    swift_unreachable("Unhandled FieldDescriptorKind in switch.");
   }
 
   const TypeInfo *visitNominalTypeRef(const NominalTypeRef *N) {
@@ -2039,7 +2039,7 @@ public:
       return TC.getTypeInfo(TC.getThinFunctionTypeRef(), ExternalTypeInfo);
     }
 
-    swift_runtime_unreachable("Unhandled FunctionMetadataConvention in switch.");
+    swift_unreachable("Unhandled FunctionMetadataConvention in switch.");
   }
 
   const TypeInfo *
@@ -2060,7 +2060,7 @@ public:
       return TC.getTypeInfo(TC.getAnyMetatypeTypeRef(), ExternalTypeInfo);
     }
 
-    swift_runtime_unreachable("Unhandled MetatypeRepresentation in switch.");
+    swift_unreachable("Unhandled MetatypeRepresentation in switch.");
   }
 
   const TypeInfo *
@@ -2256,7 +2256,7 @@ const TypeInfo *TypeConverter::getClassInstanceTypeInfo(
     return nullptr;
   }
 
-  swift_runtime_unreachable("Unhandled FieldDescriptorKind in switch.");
+  swift_unreachable("Unhandled FieldDescriptorKind in switch.");
 }
 
 } // namespace reflection

stdlib/public/SwiftRemoteMirror/SwiftRemoteMirror.cpp

@@ -23,7 +23,7 @@ unsigned long long swift_reflection_classIsSwiftMask = 2;
 #include "swift/Reflection/ReflectionContext.h"
 #include "swift/Reflection/TypeLowering.h"
 #include "swift/Remote/CMemoryReader.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 
 #if defined(__APPLE__) && defined(__MACH__)
 #include <TargetConditionals.h>
@@ -406,7 +406,7 @@ swift_layout_kind_t getTypeInfoKind(const TypeInfo &TI) {
   }
   }
 
-  swift_runtime_unreachable("Unhandled TypeInfoKind in switch");
+  swift_unreachable("Unhandled TypeInfoKind in switch");
 }
 
 static swift_typeinfo_t convertTypeInfo(const TypeInfo *TI) {

stdlib/public/runtime/Casting.cpp

@@ -35,7 +35,7 @@
 # define SWIFT_CASTING_SUPPORTS_MUTEX 1
 # include "swift/Runtime/Mutex.h"
 #endif
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/PointerIntPair.h"
 #if SWIFT_OBJC_INTEROP
@@ -1016,7 +1016,7 @@ static bool _dynamicCastToExistential(OpaqueValue *dest,
   }
   }
 
-  swift_runtime_unreachable("Unhandled ExistentialTypeRepresentation in switch.");
+  swift_unreachable("Unhandled ExistentialTypeRepresentation in switch.");
 }
 
 /******************************************************************************/
@@ -1214,7 +1214,7 @@ swift_dynamicCastMetatypeImpl(const Metadata *sourceType,
     return nullptr;
   }
 
-  swift_runtime_unreachable("Unhandled MetadataKind in switch.");
+  swift_unreachable("Unhandled MetadataKind in switch.");
 }
 
 static const Metadata *
@@ -1424,7 +1424,7 @@ static bool _dynamicCastToUnknownClassFromExistential(OpaqueValue *dest,
   }
   }
 
-  swift_runtime_unreachable(
+  swift_unreachable(
       "Unhandled ExistentialTypeRepresentation in switch.");
 }
 

stdlib/public/runtime/DynamicCast.cpp

@@ -1806,7 +1806,7 @@ static tryCastFunctionType *selectCasterForDest(const Metadata *destType) {
     case ExistentialTypeRepresentation::Error: // => Error existential
       return tryCastToErrorExistential;
     }
-    swift_runtime_unreachable(
+    swift_unreachable(
       "Unknown existential type representation in dynamic cast dispatch");
   }
   case MetadataKind::Metatype:
@@ -1821,14 +1821,14 @@ static tryCastFunctionType *selectCasterForDest(const Metadata *destType) {
     // These are internal details of runtime-only structures,
     // so will never appear in compiler-generated types.
     // As such, they don't need support here.
-    swift_runtime_unreachable(
+    swift_unreachable(
       "Unexpected MetadataKind in dynamic cast dispatch");
     return nullptr;
   default:
     // If you see this message, then there is a new MetadataKind that I didn't
     // know about when I wrote this code.  Please figure out what it is, how to
     // handle it, and add a case for it.
-    swift_runtime_unreachable(
+    swift_unreachable(
       "Unknown MetadataKind in dynamic cast dispatch");
   }
 }

stdlib/public/runtime/Exclusivity.cpp

@@ -219,7 +219,7 @@ public:
       }
     }
 
-    swift_runtime_unreachable("access not found in set");
+    swift_unreachable("access not found in set");
   }
 
 #ifndef NDEBUG

stdlib/public/runtime/Metadata.cpp

@@ -194,7 +194,7 @@ computeMetadataBoundsForSuperclass(const void *ref,
 #endif
   }
   }
-  swift_runtime_unreachable("unsupported superclass reference kind");
+  swift_unreachable("unsupported superclass reference kind");
 }
 
 static ClassMetadataBounds computeMetadataBoundsFromSuperclass(
@@ -3716,7 +3716,7 @@ getExistentialValueWitnesses(ProtocolClassConstraint classConstraint,
     return getOpaqueExistentialValueWitnesses(numWitnessTables);
   }
 
-  swift_runtime_unreachable("Unhandled ProtocolClassConstraint in switch.");
+  swift_unreachable("Unhandled ProtocolClassConstraint in switch.");
 }
 
 template<> ExistentialTypeRepresentation
@@ -3761,7 +3761,7 @@ ExistentialTypeMetadata::mayTakeValue(const OpaqueValue *container) const {
   }
   }
 
-  swift_runtime_unreachable(
+  swift_unreachable(
       "Unhandled ExistentialTypeRepresentation in switch.");
 }
 
@@ -3810,7 +3810,7 @@ ExistentialTypeMetadata::projectValue(const OpaqueValue *container) const {
   }
   }
 
-  swift_runtime_unreachable(
+  swift_unreachable(
       "Unhandled ExistentialTypeRepresentation in switch.");
 }
 
@@ -3835,7 +3835,7 @@ ExistentialTypeMetadata::getDynamicType(const OpaqueValue *container) const {
   }
   }
 
-  swift_runtime_unreachable(
+  swift_unreachable(
       "Unhandled ExistentialTypeRepresentation in switch.");
 }
 
@@ -4030,7 +4030,7 @@ class ForeignMetadataCacheEntry
     return Value;
   }
   void setValue(ValueType value) {
-    swift_runtime_unreachable("should never be called");
+    swift_unreachable("should never be called");
   }
 
 public:
@@ -4094,7 +4094,7 @@ public:
   }
 
   AllocationResult allocate(Metadata *candidate) {
-    swift_runtime_unreachable(
+    swift_unreachable(
                         "always flags allocation complete during construction");
   }
 
@@ -4555,7 +4555,7 @@ static void initProtocolWitness(void **slot, void *witness,
                                       reqt);
     return;
   }
-  swift_runtime_unreachable("bad witness kind");
+  swift_unreachable("bad witness kind");
 #else
   *slot = witness;
 #endif
@@ -4588,7 +4588,7 @@ static void copyProtocolWitness(void **dest, void * const *src,
     swift_ptrauth_copy(dest, src, reqt.Flags.getExtraDiscriminator());
     return;
   }
-  swift_runtime_unreachable("bad witness kind");
+  swift_unreachable("bad witness kind");
 #else
   *dest = *src;
 #endif
@@ -5141,7 +5141,7 @@ static const WitnessTable *swift_getAssociatedConformanceWitnessSlowImpl(
     return assocWitnessTable;
   }
 
-  swift_runtime_unreachable("Invalid mangled associate conformance");
+  swift_unreachable("Invalid mangled associate conformance");
 }
 
 const WitnessTable *swift::swift_getAssociatedConformanceWitness(
@@ -5234,7 +5234,7 @@ static Result performOnMetadataCache(const Metadata *metadata,
     case TypeContextDescriptorFlags::SingletonMetadataInitialization:
       return std::move(callbacks).forSingletonMetadata(description);
     }
-    swift_runtime_unreachable("bad metadata initialization kind");
+    swift_unreachable("bad metadata initialization kind");
   }
 
   auto &generics = description->getFullGenericContextHeader();
@@ -5280,7 +5280,7 @@ bool swift::addToMetadataQueue(MetadataCompletionQueueEntry *queueEntry,
     }
 
     bool forOtherMetadata(const Metadata *metadata) && {
-      swift_runtime_unreachable("metadata should always be complete");
+      swift_unreachable("metadata should always be complete");
     }
   } callbacks = { queueEntry, dependency };
 
@@ -5312,7 +5312,7 @@ void swift::resumeMetadataCompletion(MetadataCompletionQueueEntry *queueEntry) {
     }
 
     void forOtherMetadata(const Metadata *metadata) && {
-      swift_runtime_unreachable("metadata should always be complete");
+      swift_unreachable("metadata should always be complete");
     }
   } callbacks = { queueEntry };
 

stdlib/public/runtime/MetadataCache.h

@@ -366,7 +366,7 @@ public:
   template <class... ArgTys>
   Status beginInitialization(ConcurrencyControl &concurrency,
                              ArgTys &&...args) {
-    swift_runtime_unreachable("beginAllocation always short-circuits");
+    swift_unreachable("beginAllocation always short-circuits");
   }
 };
 
@@ -592,7 +592,7 @@ inline bool satisfies(PrivateMetadataState state, MetadataState requirement) {
   case MetadataState::Complete:
     return state >= PrivateMetadataState::Complete;
   }
-  swift_runtime_unreachable("unsupported requirement kind");
+  swift_unreachable("unsupported requirement kind");
 }
 
 class PrivateMetadataTrackingInfo {
@@ -642,7 +642,7 @@ public:
   MetadataState getAccomplishedRequestState() const {
     switch (getState()) {
     case PrivateMetadataState::Allocating:
-      swift_runtime_unreachable("cannot call on allocating state");
+      swift_unreachable("cannot call on allocating state");
     case PrivateMetadataState::Abstract:
       return MetadataState::Abstract;
     case PrivateMetadataState::LayoutComplete:
@@ -652,7 +652,7 @@ public:
     case PrivateMetadataState::Complete:
       return MetadataState::Complete;
     }
-    swift_runtime_unreachable("bad state");
+    swift_unreachable("bad state");
   }
 
   bool satisfies(MetadataState requirement) {
@@ -678,7 +678,7 @@ public:
       // Otherwise, if it's a non-blocking request, we do not need to block.
       return (request.isBlocking() && !satisfies(request.getState()));
     }
-    swift_runtime_unreachable("bad state");
+    swift_unreachable("bad state");
   }
 
   constexpr RawType getRawValue() const { return Data; }
@@ -1124,9 +1124,9 @@ private:
       return;
 
     case LSK::Complete:
-      swift_runtime_unreachable("preparing to enqueue when already complete?");
+      swift_unreachable("preparing to enqueue when already complete?");
     }
-    swift_runtime_unreachable("bad kind");
+    swift_unreachable("bad kind");
   }
 
   /// Claim all the satisfied completion queue entries, given that
@@ -1288,7 +1288,7 @@ public:
 
       switch (LockedStorageKind) {
       case LSK::Complete:
-        swift_runtime_unreachable("enqueuing on complete cache entry?");
+        swift_unreachable("enqueuing on complete cache entry?");
 
       case LSK::AllocatingThread:
         LockedStorageKind = LSK::CompletionQueue;
@@ -1340,7 +1340,7 @@ public:
       // Check for an existing dependency.
       switch (LockedStorageKind) {
       case LSK::Complete:
-        swift_runtime_unreachable("dependency on complete cache entry?");
+        swift_unreachable("dependency on complete cache entry?");
 
       case LSK::AllocatingThread:
       case LSK::CompletionQueue:

stdlib/public/runtime/MetadataLookup.cpp

@@ -88,10 +88,10 @@ static uintptr_t resolveSymbolicReferenceOffset(SymbolicReferenceKind kind,
       return (uintptr_t)contextPtr;
     }
     case SymbolicReferenceKind::AccessorFunctionReference: {
-      swift_runtime_unreachable("should not be indirectly referenced");
+      swift_unreachable("should not be indirectly referenced");
     }
     }
-    swift_runtime_unreachable("unknown symbolic reference kind");
+    swift_unreachable("unknown symbolic reference kind");
   } else {
     return ptr;
   }
@@ -176,7 +176,7 @@ _buildDemanglingForSymbolicReference(SymbolicReferenceKind kind,
                           (uintptr_t)resolvedReference);
   }
   
-  swift_runtime_unreachable("invalid symbolic reference kind");
+  swift_unreachable("invalid symbolic reference kind");
 }
   
 NodePointer
@@ -1168,7 +1168,7 @@ findAssociatedTypeByName(const ProtocolDescriptor *protocol, StringRef name) {
     ++currentAssocTypeIdx;
   }
 
-  swift_runtime_unreachable("associated type names don't line up");
+  swift_unreachable("associated type names don't line up");
 }
 
 namespace {

stdlib/public/runtime/ProtocolConformance.cpp

@@ -20,7 +20,7 @@
 #include "swift/Runtime/Concurrent.h"
 #include "swift/Runtime/HeapObject.h"
 #include "swift/Runtime/Metadata.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include "CompatibilityOverride.h"
 #include "ImageInspection.h"
 #include "Private.h"
@@ -116,7 +116,7 @@ const ClassMetadata *TypeReference::getObjCClass(TypeReferenceKind kind) const {
     return nullptr;
   }
 
-  swift_runtime_unreachable("Unhandled TypeReferenceKind in switch.");
+  swift_unreachable("Unhandled TypeReferenceKind in switch.");
 }
 #endif
 
@@ -155,7 +155,7 @@ ProtocolConformanceDescriptor::getCanonicalTypeMetadata() const {
   }
   }
 
-  swift_runtime_unreachable("Unhandled TypeReferenceKind in switch.");
+  swift_unreachable("Unhandled TypeReferenceKind in switch.");
 }
 
 template<>

stdlib/public/runtime/ReflectionMirror.cpp

@@ -17,7 +17,7 @@
 #include "swift/Runtime/HeapObject.h"
 #include "swift/Runtime/Metadata.h"
 #include "swift/Runtime/Enum.h"
-#include "swift/Runtime/Unreachable.h"
+#include "swift/Basic/Unreachable.h"
 #include "swift/Demangling/Demangle.h"
 #include "swift/Runtime/Debug.h"
 #include "swift/Runtime/Portability.h"

stdlib/toolchain/Compatibility51/ProtocolConformance.cpp

@@ -231,7 +231,7 @@ override_getCanonicalTypeMetadata(const ProtocolConformanceDescriptor *conf) {
   }
   }
 
-  swift_runtime_unreachable("Unhandled TypeReferenceKind in switch.");
+  swift_unreachable("Unhandled TypeReferenceKind in switch.");
 }
 
   class ConformanceCandidate {