intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 630 insertions, 0 deletions

diff --git a/contrib/libs/libunwind/src/AddressSpace.hpp b/contrib/libs/libunwind/src/AddressSpace.hpp
new file mode 100644
index 00000000000..0c4dfeb4e68
--- /dev/null
+++ b/contrib/libs/libunwind/src/AddressSpace.hpp
@@ -0,0 +1,630 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//
+// Abstracts accessing local vs remote address spaces.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __ADDRESSSPACE_HPP__
+#define __ADDRESSSPACE_HPP__
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libunwind.h"
+#include "config.h"
+#include "dwarf2.h"
+#include "EHHeaderParser.hpp"
+#include "Registers.hpp"
+
+#ifndef _LIBUNWIND_USE_DLADDR
+  #if !defined(_LIBUNWIND_IS_BAREMETAL) && !defined(_WIN32)
+    #define _LIBUNWIND_USE_DLADDR 1
+  #else
+    #define _LIBUNWIND_USE_DLADDR 0
+  #endif
+#endif
+
+#if _LIBUNWIND_USE_DLADDR
+#include <dlfcn.h>
+#if defined(__ELF__) && defined(_LIBUNWIND_LINK_DL_LIB)
+#pragma comment(lib, "dl")
+#endif
+#endif
+
+#if defined(_LIBUNWIND_ARM_EHABI)
+struct EHABIIndexEntry {
+  uint32_t functionOffset;
+  uint32_t data;
+};
+#endif
+
+#ifdef __APPLE__
+
+  struct dyld_unwind_sections
+  {
+    const struct mach_header*   mh;
+    const void*                 dwarf_section;
+    uintptr_t                   dwarf_section_length;
+    const void*                 compact_unwind_section;
+    uintptr_t                   compact_unwind_section_length;
+  };
+
+  // In 10.7.0 or later, libSystem.dylib implements this function.
+  extern "C" bool _dyld_find_unwind_sections(void *, dyld_unwind_sections *);
+
+#elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_LIBUNWIND_IS_BAREMETAL)
+
+// When statically linked on bare-metal, the symbols for the EH table are looked
+// up without going through the dynamic loader.
+
+// The following linker script may be used to produce the necessary sections and symbols.
+// Unless the --eh-frame-hdr linker option is provided, the section is not generated
+// and does not take space in the output file.
+//
+//   .eh_frame :
+//   {
+//       __eh_frame_start = .;
+//       KEEP(*(.eh_frame))
+//       __eh_frame_end = .;
+//   }
+//
+//   .eh_frame_hdr :
+//   {
+//       KEEP(*(.eh_frame_hdr))
+//   }
+//
+//   __eh_frame_hdr_start = SIZEOF(.eh_frame_hdr) > 0 ? ADDR(.eh_frame_hdr) : 0;
+//   __eh_frame_hdr_end = SIZEOF(.eh_frame_hdr) > 0 ? . : 0;
+
+extern char __eh_frame_start;
+extern char __eh_frame_end;
+
+#if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX)
+extern char __eh_frame_hdr_start;
+extern char __eh_frame_hdr_end;
+#endif
+
+#elif defined(_LIBUNWIND_ARM_EHABI) && defined(_LIBUNWIND_IS_BAREMETAL)
+
+// When statically linked on bare-metal, the symbols for the EH table are looked
+// up without going through the dynamic loader.
+extern char __exidx_start;
+extern char __exidx_end;
+
+#elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_WIN32)
+
+#include <windows.h>
+#include <psapi.h>
+
+#elif defined(_LIBUNWIND_USE_DL_ITERATE_PHDR) ||                               \
+      defined(_LIBUNWIND_USE_DL_UNWIND_FIND_EXIDX)
+
+#include <link.h>
+
+#endif
+
+namespace libunwind {
+
+/// Used by findUnwindSections() to return info about needed sections.
+struct UnwindInfoSections {
+#if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) ||                                \
+    defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND) ||                              \
+    defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
+  // No dso_base for SEH.
+  uintptr_t       dso_base;
+#endif
+#if defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
+  size_t          text_segment_length;
+#endif
+#if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
+  uintptr_t       dwarf_section;
+  size_t          dwarf_section_length;
+#endif
+#if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX)
+  uintptr_t       dwarf_index_section;
+  size_t          dwarf_index_section_length;
+#endif
+#if defined(_LIBUNWIND_SUPPORT_COMPACT_UNWIND)
+  uintptr_t       compact_unwind_section;
+  size_t          compact_unwind_section_length;
+#endif
+#if defined(_LIBUNWIND_ARM_EHABI)
+  uintptr_t       arm_section;
+  size_t          arm_section_length;
+#endif
+};
+
+
+/// LocalAddressSpace is used as a template parameter to UnwindCursor when
+/// unwinding a thread in the same process.  The wrappers compile away,
+/// making local unwinds fast.
+class _LIBUNWIND_HIDDEN LocalAddressSpace {
+public:
+  typedef uintptr_t pint_t;
+  typedef intptr_t  sint_t;
+  uint8_t         get8(pint_t addr) {
+    uint8_t val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  uint16_t         get16(pint_t addr) {
+    uint16_t val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  uint32_t         get32(pint_t addr) {
+    uint32_t val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  uint64_t         get64(pint_t addr) {
+    uint64_t val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  double           getDouble(pint_t addr) {
+    double val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  v128             getVector(pint_t addr) {
+    v128 val;
+    memcpy(&val, (void *)addr, sizeof(val));
+    return val;
+  }
+  uintptr_t       getP(pint_t addr);
+  uint64_t        getRegister(pint_t addr);
+  static uint64_t getULEB128(pint_t &addr, pint_t end);
+  static int64_t  getSLEB128(pint_t &addr, pint_t end);
+
+  pint_t getEncodedP(pint_t &addr, pint_t end, uint8_t encoding,
+                     pint_t datarelBase = 0);
+  bool findFunctionName(pint_t addr, char *buf, size_t bufLen,
+                        unw_word_t *offset);
+  bool findUnwindSections(pint_t targetAddr, UnwindInfoSections &info);
+  bool findOtherFDE(pint_t targetAddr, pint_t &fde);
+
+  static LocalAddressSpace sThisAddressSpace;
+};
+
+inline uintptr_t LocalAddressSpace::getP(pint_t addr) {
+#if __SIZEOF_POINTER__ == 8
+  return get64(addr);
+#else
+  return get32(addr);
+#endif
+}
+
+inline uint64_t LocalAddressSpace::getRegister(pint_t addr) {
+#if __SIZEOF_POINTER__ == 8 || defined(__mips64)
+  return get64(addr);
+#else
+  return get32(addr);
+#endif
+}
+
+/// Read a ULEB128 into a 64-bit word.
+inline uint64_t LocalAddressSpace::getULEB128(pint_t &addr, pint_t end) {
+  const uint8_t *p = (uint8_t *)addr;
+  const uint8_t *pend = (uint8_t *)end;
+  uint64_t result = 0;
+  int bit = 0;
+  do {
+    uint64_t b;
+
+    if (p == pend)
+      _LIBUNWIND_ABORT("truncated uleb128 expression");
+
+    b = *p & 0x7f;
+
+    if (bit >= 64 || b << bit >> bit != b) {
+      _LIBUNWIND_ABORT("malformed uleb128 expression");
+    } else {
+      result |= b << bit;
+      bit += 7;
+    }
+  } while (*p++ >= 0x80);
+  addr = (pint_t) p;
+  return result;
+}
+
+/// Read a SLEB128 into a 64-bit word.
+inline int64_t LocalAddressSpace::getSLEB128(pint_t &addr, pint_t end) {
+  const uint8_t *p = (uint8_t *)addr;
+  const uint8_t *pend = (uint8_t *)end;
+  int64_t result = 0;
+  int bit = 0;
+  uint8_t byte;
+  do {
+    if (p == pend)
+      _LIBUNWIND_ABORT("truncated sleb128 expression");
+    byte = *p++;
+    result |= (uint64_t)(byte & 0x7f) << bit;
+    bit += 7;
+  } while (byte & 0x80);
+  // sign extend negative numbers
+  if ((byte & 0x40) != 0 && bit < 64)
+    result |= (-1ULL) << bit;
+  addr = (pint_t) p;
+  return result;
+}
+
+inline LocalAddressSpace::pint_t
+LocalAddressSpace::getEncodedP(pint_t &addr, pint_t end, uint8_t encoding,
+                               pint_t datarelBase) {
+  pint_t startAddr = addr;
+  const uint8_t *p = (uint8_t *)addr;
+  pint_t result;
+
+  // first get value
+  switch (encoding & 0x0F) {
+  case DW_EH_PE_ptr:
+    result = getP(addr);
+    p += sizeof(pint_t);
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_uleb128:
+    result = (pint_t)getULEB128(addr, end);
+    break;
+  case DW_EH_PE_udata2:
+    result = get16(addr);
+    p += 2;
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_udata4:
+    result = get32(addr);
+    p += 4;
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_udata8:
+    result = (pint_t)get64(addr);
+    p += 8;
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_sleb128:
+    result = (pint_t)getSLEB128(addr, end);
+    break;
+  case DW_EH_PE_sdata2:
+    // Sign extend from signed 16-bit value.
+    result = (pint_t)(int16_t)get16(addr);
+    p += 2;
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_sdata4:
+    // Sign extend from signed 32-bit value.
+    result = (pint_t)(int32_t)get32(addr);
+    p += 4;
+    addr = (pint_t) p;
+    break;
+  case DW_EH_PE_sdata8:
+    result = (pint_t)get64(addr);
+    p += 8;
+    addr = (pint_t) p;
+    break;
+  default:
+    _LIBUNWIND_ABORT("unknown pointer encoding");
+  }
+
+  // then add relative offset
+  switch (encoding & 0x70) {
+  case DW_EH_PE_absptr:
+    // do nothing
+    break;
+  case DW_EH_PE_pcrel:
+    result += startAddr;
+    break;
+  case DW_EH_PE_textrel:
+    _LIBUNWIND_ABORT("DW_EH_PE_textrel pointer encoding not supported");
+    break;
+  case DW_EH_PE_datarel:
+    // DW_EH_PE_datarel is only valid in a few places, so the parameter has a
+    // default value of 0, and we abort in the event that someone calls this
+    // function with a datarelBase of 0 and DW_EH_PE_datarel encoding.
+    if (datarelBase == 0)
+      _LIBUNWIND_ABORT("DW_EH_PE_datarel is invalid with a datarelBase of 0");
+    result += datarelBase;
+    break;
+  case DW_EH_PE_funcrel:
+    _LIBUNWIND_ABORT("DW_EH_PE_funcrel pointer encoding not supported");
+    break;
+  case DW_EH_PE_aligned:
+    _LIBUNWIND_ABORT("DW_EH_PE_aligned pointer encoding not supported");
+    break;
+  default:
+    _LIBUNWIND_ABORT("unknown pointer encoding");
+    break;
+  }
+
+  if (encoding & DW_EH_PE_indirect)
+    result = getP(result);
+
+  return result;
+}
+
+#if defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
+
+// The ElfW() macro for pointer-size independent ELF header traversal is not
+// provided by <link.h> on some systems (e.g., FreeBSD). On these systems the
+// data structures are just called Elf_XXX. Define ElfW() locally.
+#if !defined(ElfW)
+  #define ElfW(type) Elf_##type
+#endif
+#if !defined(Elf_Half)
+  typedef ElfW(Half) Elf_Half;
+#endif
+#if !defined(Elf_Phdr)
+  typedef ElfW(Phdr) Elf_Phdr;
+#endif
+#if !defined(Elf_Addr)
+  typedef ElfW(Addr) Elf_Addr;
+#endif
+
+static Elf_Addr calculateImageBase(struct dl_phdr_info *pinfo) {
+  Elf_Addr image_base = pinfo->dlpi_addr;
+#if defined(__ANDROID__) && __ANDROID_API__ < 18
+  if (image_base == 0) {
+    // Normally, an image base of 0 indicates a non-PIE executable. On
+    // versions of Android prior to API 18, the dynamic linker reported a
+    // dlpi_addr of 0 for PIE executables. Compute the true image base
+    // using the PT_PHDR segment.
+    // See https://github.com/android/ndk/issues/505.
+    for (Elf_Half i = 0; i < pinfo->dlpi_phnum; i++) {
+      const Elf_Phdr *phdr = &pinfo->dlpi_phdr[i];
+      if (phdr->p_type == PT_PHDR) {
+        image_base = reinterpret_cast<Elf_Addr>(pinfo->dlpi_phdr) -
+          phdr->p_vaddr;
+        break;
+      }
+    }
+  }
+#endif
+  return image_base;
+}
+
+struct _LIBUNWIND_HIDDEN dl_iterate_cb_data {
+  LocalAddressSpace *addressSpace;
+  UnwindInfoSections *sects;
+  uintptr_t targetAddr;
+};
+
+#if defined(_LIBUNWIND_USE_FRAME_HEADER_CACHE)
+#include "FrameHeaderCache.hpp"
+
+// Typically there is one cache per process, but when libunwind is built as a
+// hermetic static library, then each shared object may have its own cache.
+static FrameHeaderCache TheFrameHeaderCache;
+#endif
+
+static bool checkAddrInSegment(const Elf_Phdr *phdr, size_t image_base,
+                               dl_iterate_cb_data *cbdata) {
+  if (phdr->p_type == PT_LOAD) {
+    uintptr_t begin = image_base + phdr->p_vaddr;
+    uintptr_t end = begin + phdr->p_memsz;
+    if (cbdata->targetAddr >= begin && cbdata->targetAddr < end) {
+      cbdata->sects->dso_base = begin;
+      cbdata->sects->text_segment_length = phdr->p_memsz;
+      return true;
+    }
+  }
+  return false;
+}
+
+static bool checkForUnwindInfoSegment(const Elf_Phdr *phdr, size_t image_base,
+                                      dl_iterate_cb_data *cbdata) {
+#if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX)
+  if (phdr->p_type == PT_GNU_EH_FRAME) {
+    EHHeaderParser<LocalAddressSpace>::EHHeaderInfo hdrInfo;
+    uintptr_t eh_frame_hdr_start = image_base + phdr->p_vaddr;
+    cbdata->sects->dwarf_index_section = eh_frame_hdr_start;
+    cbdata->sects->dwarf_index_section_length = phdr->p_memsz;
+    if (EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
+            *cbdata->addressSpace, eh_frame_hdr_start, phdr->p_memsz,
+            hdrInfo)) {
+      // .eh_frame_hdr records the start of .eh_frame, but not its size.
+      // Rely on a zero terminator to find the end of the section.
+      cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
+      cbdata->sects->dwarf_section_length = SIZE_MAX;
+      return true;
+    }
+  }
+  return false;
+#elif defined(_LIBUNWIND_ARM_EHABI)
+  if (phdr->p_type == PT_ARM_EXIDX) {
+    uintptr_t exidx_start = image_base + phdr->p_vaddr;
+    cbdata->sects->arm_section = exidx_start;
+    cbdata->sects->arm_section_length = phdr->p_memsz;
+    return true;
+  }
+  return false;
+#else
+#error Need one of _LIBUNWIND_SUPPORT_DWARF_INDEX or _LIBUNWIND_ARM_EHABI
+#endif
+}
+
+static int findUnwindSectionsByPhdr(struct dl_phdr_info *pinfo,
+                                    size_t pinfo_size, void *data) {
+  auto cbdata = static_cast<dl_iterate_cb_data *>(data);
+  if (pinfo->dlpi_phnum == 0 || cbdata->targetAddr < pinfo->dlpi_addr)
+    return 0;
+#if defined(_LIBUNWIND_USE_FRAME_HEADER_CACHE)
+  if (TheFrameHeaderCache.find(pinfo, pinfo_size, data))
+    return 1;
+#else
+  // Avoid warning about unused variable.
+  (void)pinfo_size;
+#endif
+
+  Elf_Addr image_base = calculateImageBase(pinfo);
+
+  // Most shared objects seen in this callback function likely don't contain the
+  // target address, so optimize for that. Scan for a matching PT_LOAD segment
+  // first and bail when it isn't found.
+  bool found_text = false;
+  for (Elf_Half i = 0; i < pinfo->dlpi_phnum; ++i) {
+    if (checkAddrInSegment(&pinfo->dlpi_phdr[i], image_base, cbdata)) {
+      found_text = true;
+      break;
+    }
+  }
+  if (!found_text)
+    return 0;
+
+  // PT_GNU_EH_FRAME and PT_ARM_EXIDX are usually near the end. Iterate
+  // backward.
+  bool found_unwind = false;
+  for (Elf_Half i = pinfo->dlpi_phnum; i > 0; i--) {
+    const Elf_Phdr *phdr = &pinfo->dlpi_phdr[i - 1];
+    if (checkForUnwindInfoSegment(phdr, image_base, cbdata)) {
+      found_unwind = true;
+      break;
+    }
+  }
+  if (!found_unwind)
+    return 0;
+
+#if defined(_LIBUNWIND_USE_FRAME_HEADER_CACHE)
+  TheFrameHeaderCache.add(cbdata->sects);
+#endif
+  return 1;
+}
+
+#endif  // defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
+
+
+inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
+                                                  UnwindInfoSections &info) {
+#ifdef __APPLE__
+  dyld_unwind_sections dyldInfo;
+  if (_dyld_find_unwind_sections((void *)targetAddr, &dyldInfo)) {
+    info.dso_base                      = (uintptr_t)dyldInfo.mh;
+ #if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
+    info.dwarf_section                 = (uintptr_t)dyldInfo.dwarf_section;
+    info.dwarf_section_length          = (size_t)dyldInfo.dwarf_section_length;
+ #endif
+    info.compact_unwind_section        = (uintptr_t)dyldInfo.compact_unwind_section;
+    info.compact_unwind_section_length = (size_t)dyldInfo.compact_unwind_section_length;
+    return true;
+  }
+#elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_LIBUNWIND_IS_BAREMETAL)
+  info.dso_base = 0;
+  // Bare metal is statically linked, so no need to ask the dynamic loader
+  info.dwarf_section_length = (size_t)(&__eh_frame_end - &__eh_frame_start);
+  info.dwarf_section =        (uintptr_t)(&__eh_frame_start);
+  _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: section %p length %p",
+                             (void *)info.dwarf_section, (void *)info.dwarf_section_length);
+#if defined(_LIBUNWIND_SUPPORT_DWARF_INDEX)
+  info.dwarf_index_section =        (uintptr_t)(&__eh_frame_hdr_start);
+  info.dwarf_index_section_length = (size_t)(&__eh_frame_hdr_end - &__eh_frame_hdr_start);
+  _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: index section %p length %p",
+                             (void *)info.dwarf_index_section, (void *)info.dwarf_index_section_length);
+#endif
+  if (info.dwarf_section_length)
+    return true;
+#elif defined(_LIBUNWIND_ARM_EHABI) && defined(_LIBUNWIND_IS_BAREMETAL)
+  // Bare metal is statically linked, so no need to ask the dynamic loader
+  info.arm_section =        (uintptr_t)(&__exidx_start);
+  info.arm_section_length = (size_t)(&__exidx_end - &__exidx_start);
+  _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: section %p length %p",
+                             (void *)info.arm_section, (void *)info.arm_section_length);
+  if (info.arm_section && info.arm_section_length)
+    return true;
+#elif defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) && defined(_WIN32)
+  HMODULE mods[1024];
+  HANDLE process = GetCurrentProcess();
+  DWORD needed;
+
+  if (!EnumProcessModules(process, mods, sizeof(mods), &needed)) {
+    DWORD err = GetLastError();
+    _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: EnumProcessModules failed, "
+                               "returned error %d", (int)err);
+    return false;
+  }
+
+  for (unsigned i = 0; i < (needed / sizeof(HMODULE)); i++) {
+    PIMAGE_DOS_HEADER pidh = (PIMAGE_DOS_HEADER)mods[i];
+    PIMAGE_NT_HEADERS pinh = (PIMAGE_NT_HEADERS)((BYTE *)pidh + pidh->e_lfanew);
+    PIMAGE_FILE_HEADER pifh = (PIMAGE_FILE_HEADER)&pinh->FileHeader;
+    PIMAGE_SECTION_HEADER pish = IMAGE_FIRST_SECTION(pinh);
+    bool found_obj = false;
+    bool found_hdr = false;
+
+    info.dso_base = (uintptr_t)mods[i];
+    for (unsigned j = 0; j < pifh->NumberOfSections; j++, pish++) {
+      uintptr_t begin = pish->VirtualAddress + (uintptr_t)mods[i];
+      uintptr_t end = begin + pish->Misc.VirtualSize;
+      if (!strncmp((const char *)pish->Name, ".text",
+                   IMAGE_SIZEOF_SHORT_NAME)) {
+        if (targetAddr >= begin && targetAddr < end)
+          found_obj = true;
+      } else if (!strncmp((const char *)pish->Name, ".eh_frame",
+                          IMAGE_SIZEOF_SHORT_NAME)) {
+        info.dwarf_section = begin;
+        info.dwarf_section_length = pish->Misc.VirtualSize;
+        found_hdr = true;
+      }
+      if (found_obj && found_hdr)
+        return true;
+    }
+  }
+  return false;
+#elif defined(_LIBUNWIND_SUPPORT_SEH_UNWIND) && defined(_WIN32)
+  // Don't even bother, since Windows has functions that do all this stuff
+  // for us.
+  (void)targetAddr;
+  (void)info;
+  return true;
+#elif defined(_LIBUNWIND_USE_DL_UNWIND_FIND_EXIDX)
+  int length = 0;
+  info.arm_section =
+      (uintptr_t)dl_unwind_find_exidx((_Unwind_Ptr)targetAddr, &length);
+  info.arm_section_length = (size_t)length * sizeof(EHABIIndexEntry);
+  if (info.arm_section && info.arm_section_length)
+    return true;
+#elif defined(_LIBUNWIND_USE_DL_ITERATE_PHDR)
+  dl_iterate_cb_data cb_data = {this, &info, targetAddr};
+  int found = dl_iterate_phdr(findUnwindSectionsByPhdr, &cb_data);
+  return static_cast<bool>(found);
+#endif
+
+  return false;
+}
+
+
+inline bool LocalAddressSpace::findOtherFDE(pint_t targetAddr, pint_t &fde) {
+  // TO DO: if OS has way to dynamically register FDEs, check that.
+  (void)targetAddr;
+  (void)fde;
+  return false;
+}
+
+inline bool LocalAddressSpace::findFunctionName(pint_t addr, char *buf,
+                                                size_t bufLen,
+                                                unw_word_t *offset) {
+#if _LIBUNWIND_USE_DLADDR
+  Dl_info dyldInfo;
+  if (dladdr((void *)addr, &dyldInfo)) {
+    if (dyldInfo.dli_sname != NULL) {
+      snprintf(buf, bufLen, "%s", dyldInfo.dli_sname);
+      *offset = (addr - (pint_t) dyldInfo.dli_saddr);
+      return true;
+    }
+  }
+#else
+  (void)addr;
+  (void)buf;
+  (void)bufLen;
+  (void)offset;
+#endif
+  return false;
+}
+
+} // namespace libunwind
+
+#endif // __ADDRESSSPACE_HPP__