[Backtracing][Linux] Reorganise modules for _Backtracing.

Using `SwiftShims` is undesirable - it creates all kinds of build issues,
and means shipping the `_SwiftBacktracing.h` header in the SDK, which is
not necessary.

While we're doing this, add the necessary definitions for reading ELF
and DWARF information.

rdar://110261712

Author: al45tair

stdlib/public/SwiftShims/swift/shims/CrashInfo.h renamed to 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
 

stdlib/public/Backtracing/CMakeLists.txt

@@ -30,12 +30,26 @@ set(BACKTRACING_SOURCES
   Registers.swift
   SymbolicatedBacktrace.swift
   Utils.swift
-  Shims.cpp
+  Win32Extras.cpp
 
   get-cpu-context.${SWIFT_ASM_EXT}
 )
 
-set(BACKTRACING_COMPILE_FLAGS)
+set(BACKTRACING_COMPILE_FLAGS
+  "-Xfrontend;-experimental-spi-only-imports"
+  "-Xcc;-I${SWIFT_SOURCE_DIR}/include"
+  "-Xcc;-I${CMAKE_BINARY_DIR}/include"
+  "-Xcc;-fno-implicit-module-maps"
+  "-Xcc;-fbuiltin-module-map"
+  "-Xcc;-fmodule-map-file=${SWIFT_STDLIB_SOURCE_DIR}/public/SwiftShims/swift/shims/module.modulemap"
+  "-Xcc;-fmodule-map-file=${SWIFT_STDLIB_SOURCE_DIR}/public/Backtracing/modules/module.modulemap")
+
+###TODO: Add these when we add static linking support
+#
+#list(APPEND BACKTRACING_COMPILE_FLAGS
+#  "-Xcc;-I${SWIFT_PATH_TO_ZLIB_SOURCE}"
+#  "-Xcc;-I${SWIFT_PATH_TO_ZSTD_SOURCE}/lib"
+#  "-Xcc;-I${SWIFT_PATH_TO_LIBLZMA_SOURCE}/src/liblzma/api")
 
 if(SWIFT_ASM_AVAILABLE)
   list(APPEND BACKTRACING_SOURCES get-cpu-context.${SWIFT_ASM_EXT})
@@ -52,7 +66,7 @@ set(LLVM_OPTIONAL_SOURCES
 add_swift_target_library(swift_Backtracing ${SWIFT_STDLIB_LIBRARY_BUILD_TYPES} IS_STDLIB
   ${BACKTRACING_SOURCES}
 
-  SWIFT_MODULE_DEPENDS ${concurrency}
+  SWIFT_MODULE_DEPENDS ${concurrency} _StringProcessing
 
   LINK_LIBRARIES ${swift_backtracing_link_libraries}
 

stdlib/public/Backtracing/Shims.cpp

@@ -0,0 +1,168 @@
+//===--- Compression.h - C decls for compression libraries ------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Includes and definitions to allow us to use the compression libraries
+// (zlib, zstd and liblzma) in the backtracing module.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_BACKTRACING_COMPRESSION_H
+#define SWIFT_BACKTRACING_COMPRESSION_H
+
+#include <stdint.h>
+#include <stdlib.h>
+
+// Right now, we're soft linking to zlib/zstd/liblzma, so that users don't
+// need it installed (but if they try to do something that requires it,
+// they'll see an error message).
+//
+// As a result, we've grabbed copies of the relevant definitions here so
+// that we don't need to install the -dev packages in order to build Swift.
+
+#if SWIFT_BACKTRACE_STATIC_ZLIB
+#include "zlib.h"
+#else
+// This is the version we took the z_stream structure from
+#define ZLIB_VERSION "1.2.11"
+
+#define Z_OK 0
+#define Z_STREAM_END 1
+
+#define Z_NO_FLUSH 0
+
+typedef struct z_stream_s {
+  uint8_t *next_in;
+  unsigned avail_in;
+  unsigned long total_in;
+
+  uint8_t *next_out;
+  unsigned avail_out;
+  unsigned long total_out;
+
+  const char *msg;
+  struct internal_state *state;
+
+  void (*zalloc)(void *, unsigned, unsigned);
+  void (*zfree)(void *, void *);
+  void *opaque;
+
+  int data_type;
+
+  unsigned long adler;
+  unsigned long reserved;
+} z_stream;
+
+typedef z_stream *z_streamp;
+#endif
+
+#if SWIFT_BACKTRACE_STATIC_ZSTD
+#include "zstd.h"
+#else
+typedef struct ZSTD_inBuffer_s {
+  const void *src;
+  size_t size;
+  size_t pos;
+} ZSTD_inBuffer;
+
+typedef struct ZSTD_outBuffer_s {
+  void *dst;
+  size_t size;
+  size_t pos;
+} ZSTD_outBuffer;
+#endif
+
+#if SWIFT_BACKTRACE_STATIC_LIBLZMA
+#include "lzma.h"
+#else
+typedef enum {
+  LZMA_OK = 0,
+  LZMA_STREAM_END = 1,
+  LZMA_NO_CHECK = 2,
+  LZMA_UNSUPPORTED_CHECK = 3,
+  LZMA_GET_CHECK = 4,
+  LZMA_MEM_ERROR = 5,
+  LZMA_MEMLIMIT_ERROR = 6,
+  LZMA_FORMAT_ERROR = 7,
+  LZMA_OPTIONS_ERROR = 8,
+  LZMA_DATA_ERROR = 9,
+  LZMA_BUF_ERROR = 10,
+  LZMA_PROG_ERROR = 11,
+} lzma_ret;
+
+typedef enum {
+  LZMA_RUN = 0,
+  LZMA_SYNC_FLUSH = 1,
+  LZMA_FULL_FLUSH = 2,
+  LZMA_FULL_BARRIER = 4,
+  LZMA_FINISH = 3
+} lzma_action;
+
+typedef enum {
+  LZMA_RESERVED_ENUM = 0,
+} lzma_reserved_enum;
+
+typedef struct {
+  void *(*alloc)(void *, size_t, size_t);
+  void (*free)(void *, void *);
+  void *opaque;
+} lzma_allocator;
+
+typedef struct lzma_internal_s lzma_internal;
+
+typedef struct {
+  const uint8_t *next_in;
+  size_t avail_in;
+  uint64_t total_in;
+
+  uint8_t *next_out;
+  size_t avail_out;
+  uint64_t total_out;
+
+  const lzma_allocator *allocator;
+
+  lzma_internal *internal;
+
+  void *reserved_ptr1;
+  void *reserved_ptr2;
+  void *reserved_ptr3;
+  void *reserved_ptr4;
+  uint64_t reserved_int1;
+  uint64_t reserved_int2;
+  size_t reserved_int3;
+  size_t reserved_int4;
+  lzma_reserved_enum reserved_enum1;
+  lzma_reserved_enum reserved_enum2;
+} lzma_stream;
+
+#define LZMA_STREAM_INIT {0}
+#endif
+
+#ifdef __cplusplus
+namespace swift {
+extern "C" {
+#endif
+
+// The Swift importer can't cope with complex macros; it will do inline
+// functions, however.
+static inline lzma_stream lzma_stream_init() {
+  return (lzma_stream)LZMA_STREAM_INIT;
+}
+static inline z_stream zlib_stream_init() {
+  return (z_stream){ 0 };
+}
+
+#ifdef __cplusplus
+} // extern "C"
+} // namespace swift
+#endif
+
+#endif // SWIFT_BACKTRACING_COMPRESSION_H

stdlib/public/Backtracing/modules/Compression.h

@@ -0,0 +1,60 @@
+//===--- FixedLayout.h - Types whose layout must be fixed -------*- C++ -*-===//
+//
+// 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 types whose in-memory layout must be fixed, which therefore have
+//  to be defined using C code.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SWIFT_BACKTRACING_FIXED_LAYOUT_H
+#define SWIFT_BACKTRACING_FIXED_LAYOUT_H
+
+#ifdef __cplusplus
+namespace swift {
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+struct x86_64_gprs {
+  uint64_t _r[16];
+  uint64_t rflags;
+  uint16_t cs, fs, gs, _pad0;
+  uint64_t rip;
+  uint64_t valid;
+};
+
+struct i386_gprs {
+  uint32_t _r[8];
+  uint32_t eflags;
+  uint16_t segreg[6];
+  uint32_t eip;
+  uint32_t valid;
+};
+
+struct arm64_gprs {
+  uint64_t _x[32];
+  uint64_t pc;
+  uint64_t valid;
+};
+
+struct arm_gprs {
+  uint32_t _r[16];
+  uint32_t valid;
+};
+
+#ifdef __cpluspus
+} // extern "C"
+} // namespace swift
+#endif
+
+#endif // SWIFT_BACKTRACING_FIXED_LAYOUT_H