[Backtracing][Linux] Add Linux support.

include/swift/AST/SemanticAttrs.def

@@ -144,5 +144,8 @@ SEMANTICS_ATTR(NO_PERFORMANCE_ANALYSIS, "no_performance_analysis")
 // that may cause the user to think there is a bug in the compiler.
 SEMANTICS_ATTR(NO_MOVEONLY_DIAGNOSTICS, "sil.optimizer.moveonly.diagnostic.ignore")
 
+// Force the use of the frame pointer for the specified function
+SEMANTICS_ATTR(USE_FRAME_POINTER, "use_frame_pointer")
+
 #undef SEMANTICS_ATTR
 

include/swift/Runtime/Backtrace.h

@@ -17,10 +17,17 @@
 #ifndef SWIFT_RUNTIME_BACKTRACE_H
 #define SWIFT_RUNTIME_BACKTRACE_H
 
+#ifdef __linux__
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <signal.h>
+#endif // defined(__linux__)
+
 #include "swift/Runtime/Config.h"
+#include "swift/Runtime/CrashInfo.h"
 
 #include "swift/shims/Visibility.h"
-#include "swift/shims/CrashInfo.h"
 
 #include <inttypes.h>
 
@@ -50,7 +57,11 @@ typedef int ErrorCode;
 
 SWIFT_RUNTIME_STDLIB_INTERNAL ErrorCode _swift_installCrashHandler();
 
+#ifdef __linux__
+SWIFT_RUNTIME_STDLIB_INTERNAL bool _swift_spawnBacktracer(const ArgChar * const *argv, int memserver_fd);
+#else
 SWIFT_RUNTIME_STDLIB_INTERNAL bool _swift_spawnBacktracer(const ArgChar * const *argv);
+#endif
 
 enum class UnwindAlgorithm {
   Auto = 0,
@@ -123,8 +134,15 @@ struct BacktraceSettings {
 
 SWIFT_RUNTIME_STDLIB_INTERNAL BacktraceSettings _swift_backtraceSettings;
 
-SWIFT_RUNTIME_STDLIB_SPI SWIFT_CC(swift) bool _swift_isThunkFunction(const char *mangledName);
+SWIFT_RUNTIME_STDLIB_SPI
+bool _swift_backtrace_isThunkFunction(const char *mangledName);
 
+SWIFT_RUNTIME_STDLIB_SPI
+char *_swift_backtrace_demangle(const char *mangledName,
+                                size_t mangledNameLength,
+                                char *outputBuffer,
+                                size_t *outputBufferSize,
+                                int *status);
 #ifdef __cplusplus
 } // namespace backtrace
 } // namespace runtime

include/swift/Runtime/Config.h

@@ -493,8 +493,8 @@ swift_auth_code(T value, unsigned extra) {
 #elif defined(_WIN32)
 #  define SWIFT_BACKTRACE_ON_CRASH_SUPPORTED 0
 #  define SWIFT_BACKTRACE_SECTION ".sw5bckt"
-#elif defined(__linux__)
-#  define SWIFT_BACKTRACE_ON_CRASH_SUPPORTED 0
+#elif defined(__linux__) && (defined(__aarch64__) || defined(__x86_64__))
+#  define SWIFT_BACKTRACE_ON_CRASH_SUPPORTED 1
 #  define SWIFT_BACKTRACE_SECTION "swift5_backtrace"
 #else
 #  define SWIFT_BACKTRACE_ON_CRASH_SUPPORTED 0

stdlib/public/SwiftShims/swift/shims/CrashInfo.h → include/swift/Runtime/CrashInfo.h

@@ -18,22 +18,52 @@
 #ifndef SWIFT_CRASHINFO_H
 #define SWIFT_CRASHINFO_H
 
-#include "SwiftStdint.h"
+#include <inttypes.h>
 
 #ifdef __cplusplus
 namespace swift {
+namespace runtime {
+namespace backtrace {
 extern "C" {
 #endif
 
 struct CrashInfo {
-  __swift_uint64_t crashing_thread;
-  __swift_uint64_t signal;
-  __swift_uint64_t fault_address;
-  __swift_uint64_t mctx;
+  uint64_t crashing_thread;
+  uint64_t signal;
+  uint64_t fault_address;
+
+#ifdef __APPLE__
+  uint64_t mctx;
+#elif defined(__linux__)
+  uint64_t thread_list;
+#endif
+};
+
+#ifdef __linux__
+
+struct memserver_req {
+  uint64_t addr;
+  uint64_t len;
 };
 
+struct memserver_resp {
+  uint64_t addr;
+  int64_t  len;
+  /* Then len bytes of data */
+};
+
+struct thread {
+  uint64_t next;
+  int64_t  tid;
+  uint64_t uctx;
+};
+
+#endif
+
 #ifdef __cplusplus
 } // extern "C"
+} // namespace backtrace
+} // namespace runtime
 } // namespace swift
 #endif
 

include/swift/Runtime/Debug.h

@@ -124,6 +124,9 @@ swift_dynamicCastFailure(const void *sourceType, const char *sourceName,
 SWIFT_RUNTIME_EXPORT
 void swift_reportError(uint32_t flags, const char *message);
 
+SWIFT_RUNTIME_EXPORT
+void swift_reportWarning(uint32_t flags, const char *message);
+
 // Halt due to an overflow in swift_retain().
 SWIFT_RUNTIME_ATTRIBUTE_NORETURN SWIFT_RUNTIME_ATTRIBUTE_NOINLINE
 void swift_abortRetainOverflow();

lib/IRGen/IRGenSIL.cpp

@@ -21,6 +21,7 @@
 #include "swift/AST/IRGenOptions.h"
 #include "swift/AST/ParameterList.h"
 #include "swift/AST/Pattern.h"
+#include "swift/AST/SemanticAttrs.h"
 #include "swift/AST/SubstitutionMap.h"
 #include "swift/AST/Types.h"
 #include "swift/Basic/ExternalUnion.h"
@@ -1835,6 +1836,11 @@ IRGenSILFunction::IRGenSILFunction(IRGenModule &IGM, SILFunction *f)
     }
   }
 
+  // If we have @_semantics("use_frame_pointer"), force the use of a
+  // frame pointer for this function.
+  if (f->hasSemanticsAttr(semantics::USE_FRAME_POINTER))
+    CurFn->addFnAttr("frame-pointer", "all");
+
   // Disable inlining of coroutine functions until we split.
   if (f->getLoweredFunctionType()->isCoroutine()) {
     CurFn->addFnAttr(llvm::Attribute::NoInline);

stdlib/public/Backtracing/ArrayImageSource.swift

@@ -0,0 +1,50 @@
+//===--- ArrayImageSource.swift - An image source backed by an Array -------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2023 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines ArrayImageSource, an image source that is backed by a Swift Array.
+//
+//===----------------------------------------------------------------------===//
+
+import Swift
+
+@_implementationOnly import OS.Libc
+
+enum ArrayImageSourceError: Error {
+  case outOfBoundsRead(UInt64, UInt64)
+}
+
+struct ArrayImageSource<T>: ImageSource {
+  private var array: Array<T>
+
+  public init(array: Array<T>) {
+    self.array = array
+  }
+
+  public var isMappedImage: Bool { return false }
+  public var path: String? { return nil }
+  public var bounds: Bounds? {
+    return Bounds(base: 0, size: Size(array.count * MemoryLayout<T>.stride))
+  }
+
+  public func fetch<U>(from addr: Address,
+                       into buffer: UnsafeMutableBufferPointer<U>) throws {
+    try array.withUnsafeBytes{
+      let size = Size($0.count)
+      let requested = Size(buffer.count * MemoryLayout<U>.stride)
+      if addr > size || requested > size - addr {
+        throw ArrayImageSourceError.outOfBoundsRead(addr, requested)
+      }
+
+      memcpy(buffer.baseAddress!, $0.baseAddress! + Int(addr), Int(requested))
+    }
+  }
+}