Bring LLVM libunwind snapshot into contrib/llvm/projects

1 files changed, 593 insertions, 0 deletions

diff --git a/contrib/llvm/projects/libunwind/src/AddressSpace.hpp b/contrib/llvm/projects/libunwind/src/AddressSpace.hpp
new file mode 100644
index 0000000..567cbda
--- /dev/null
+++ b/contrib/llvm/projects/libunwind/src/AddressSpace.hpp
@@ -0,0 +1,593 @@
+//===------------------------- AddressSpace.hpp ---------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//
+// 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>
+
+#ifndef _LIBUNWIND_IS_BAREMETAL
+#include <dlfcn.h>
+#endif
+
+#ifdef __APPLE__
+#include <mach-o/getsect.h>
+namespace libunwind {
+   bool checkKeyMgrRegisteredFDEs(uintptr_t targetAddr, void *&fde);
+}
+#endif
+
+#include "libunwind.h"
+#include "config.h"
+#include "dwarf2.h"
+#include "Registers.hpp"
+
+#if _LIBUNWIND_ARM_EHABI
+#ifdef __linux__
+
+typedef long unsigned int *_Unwind_Ptr;
+extern "C" _Unwind_Ptr __gnu_Unwind_Find_exidx(_Unwind_Ptr addr, int *len);
+
+// Emulate the BSD dl_unwind_find_exidx API when on a GNU libdl system.
+#define dl_unwind_find_exidx __gnu_Unwind_Find_exidx
+
+#elif !defined(_LIBUNWIND_IS_BAREMETAL)
+#include <link.h>
+#else // !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.
+struct EHTEntry {
+  uint32_t functionOffset;
+  uint32_t unwindOpcodes;
+};
+extern EHTEntry __exidx_start;
+extern EHTEntry __exidx_end;
+#endif // !defined(_LIBUNWIND_IS_BAREMETAL)
+#endif // _LIBUNWIND_ARM_EHABI
+
+#if defined(__CloudABI__) || defined(__FreeBSD__) || defined(__linux__)
+#if _LIBUNWIND_SUPPORT_DWARF_UNWIND && _LIBUNWIND_SUPPORT_DWARF_INDEX
+#include <link.h>
+// Macro for machine-independent access to the ELF program headers. This
+// macro is not available 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
+#include "EHHeaderParser.hpp"
+#endif
+#endif
+
+namespace libunwind {
+
+/// Used by findUnwindSections() to return info about needed sections.
+struct UnwindInfoSections {
+#if _LIBUNWIND_SUPPORT_DWARF_UNWIND || _LIBUNWIND_SUPPORT_DWARF_INDEX ||       \
+    _LIBUNWIND_SUPPORT_COMPACT_UNWIND
+  // No dso_base for ARM EHABI.
+  uintptr_t       dso_base;
+#endif
+#if _LIBUNWIND_SUPPORT_DWARF_UNWIND
+  uintptr_t       dwarf_section;
+  uintptr_t       dwarf_section_length;
+#endif
+#if _LIBUNWIND_SUPPORT_DWARF_INDEX
+  uintptr_t       dwarf_index_section;
+  uintptr_t       dwarf_index_section_length;
+#endif
+#if _LIBUNWIND_SUPPORT_COMPACT_UNWIND
+  uintptr_t       compact_unwind_section;
+  uintptr_t       compact_unwind_section_length;
+#endif
+#if _LIBUNWIND_ARM_EHABI
+  uintptr_t       arm_section;
+  uintptr_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 __attribute__((visibility("hidden"))) LocalAddressSpace {
+public:
+#ifdef __LP64__
+  typedef uint64_t pint_t;
+  typedef int64_t  sint_t;
+#else
+  typedef uint32_t pint_t;
+  typedef int32_t  sint_t;
+#endif
+  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);
+  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) {
+#ifdef __LP64__
+  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 |= ((byte & 0x7f) << bit);
+    bit += 7;
+  } while (byte & 0x80);
+  // sign extend negative numbers
+  if ((byte & 0x40) != 0)
+    result |= (-1LL) << 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;
+}
+
+#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;
+  };
+  #if (defined(__MAC_OS_X_VERSION_MIN_REQUIRED) \
+                                 && (__MAC_OS_X_VERSION_MIN_REQUIRED >= 1070)) \
+      || defined(__IPHONE_OS_VERSION_MIN_REQUIRED)
+    // In 10.7.0 or later, libSystem.dylib implements this function.
+    extern "C" bool _dyld_find_unwind_sections(void *, dyld_unwind_sections *);
+  #else
+    // In 10.6.x and earlier, we need to implement this functionality.
+    static inline bool _dyld_find_unwind_sections(void* addr, 
+                                                    dyld_unwind_sections* info) {
+      // Find mach-o image containing address.
+      Dl_info dlinfo;
+      if (!dladdr(addr, &dlinfo))
+        return false;
+      const mach_header *mh = (const mach_header *)dlinfo.dli_saddr;
+      
+      // Find dwarf unwind section in that image.
+      unsigned long size;
+      const uint8_t *p = getsectiondata(mh, "__TEXT", "__eh_frame", &size);
+      if (!p)
+        return false;
+      
+      // Fill in return struct.
+      info->mh = mh;
+      info->dwarf_section = p;
+      info->dwarf_section_length = size;
+      info->compact_unwind_section = 0;
+      info->compact_unwind_section_length = 0;
+     
+      return true;
+    }
+  #endif
+#endif
+
+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 _LIBUNWIND_SUPPORT_DWARF_UNWIND
+    info.dwarf_section                 = (uintptr_t)dyldInfo.dwarf_section;
+    info.dwarf_section_length          = dyldInfo.dwarf_section_length;
+ #endif
+    info.compact_unwind_section        = (uintptr_t)dyldInfo.compact_unwind_section;
+    info.compact_unwind_section_length = dyldInfo.compact_unwind_section_length;
+    return true;
+  }
+#elif _LIBUNWIND_ARM_EHABI
+ #ifdef _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 = (uintptr_t)(&__exidx_end - &__exidx_start);
+ #else
+  int length = 0;
+  info.arm_section = (uintptr_t) dl_unwind_find_exidx(
+      (_Unwind_Ptr) targetAddr, &length);
+  info.arm_section_length = (uintptr_t)length;
+ #endif
+  _LIBUNWIND_TRACE_UNWINDING("findUnwindSections: section %X length %x\n",
+                             info.arm_section, info.arm_section_length);
+  if (info.arm_section && info.arm_section_length)
+    return true;
+#elif _LIBUNWIND_SUPPORT_DWARF_UNWIND
+#if _LIBUNWIND_SUPPORT_DWARF_INDEX
+  struct dl_iterate_cb_data {
+    LocalAddressSpace *addressSpace;
+    UnwindInfoSections *sects;
+    uintptr_t targetAddr;
+  };
+
+  dl_iterate_cb_data cb_data = {this, &info, targetAddr};
+  int found = dl_iterate_phdr(
+      [](struct dl_phdr_info *pinfo, size_t, void *data) -> int {
+        auto cbdata = static_cast<dl_iterate_cb_data *>(data);
+        size_t object_length;
+        bool found_obj = false;
+        bool found_hdr = false;
+
+        assert(cbdata);
+        assert(cbdata->sects);
+
+        if (cbdata->targetAddr < pinfo->dlpi_addr) {
+          return false;
+        }
+
+#if !defined(Elf_Half)
+        typedef ElfW(Half) Elf_Half;
+#endif
+#if !defined(Elf_Phdr)
+        typedef ElfW(Phdr) Elf_Phdr;
+#endif
+
+        for (Elf_Half i = 0; i < pinfo->dlpi_phnum; i++) {
+          const Elf_Phdr *phdr = &pinfo->dlpi_phdr[i];
+          if (phdr->p_type == PT_LOAD) {
+            uintptr_t begin = pinfo->dlpi_addr + phdr->p_vaddr;
+            uintptr_t end = begin + phdr->p_memsz;
+            if (cbdata->targetAddr >= begin && cbdata->targetAddr < end) {
+              cbdata->sects->dso_base = begin;
+              object_length = phdr->p_memsz;
+              found_obj = true;
+            }
+          } else if (phdr->p_type == PT_GNU_EH_FRAME) {
+            EHHeaderParser<LocalAddressSpace>::EHHeaderInfo hdrInfo;
+            uintptr_t eh_frame_hdr_start = pinfo->dlpi_addr + phdr->p_vaddr;
+            cbdata->sects->dwarf_index_section = eh_frame_hdr_start;
+            cbdata->sects->dwarf_index_section_length = phdr->p_memsz;
+            EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
+                *cbdata->addressSpace, eh_frame_hdr_start, phdr->p_memsz,
+                hdrInfo);
+            cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
+            found_hdr = true;
+          }
+        }
+
+        if (found_obj && found_hdr) {
+          cbdata->sects->dwarf_section_length = object_length;
+          return true;
+        } else {
+          return false;
+        }
+      },
+      &cb_data);
+  return static_cast<bool>(found);
+#else
+#error "_LIBUNWIND_SUPPORT_DWARF_UNWIND requires _LIBUNWIND_SUPPORT_DWARF_INDEX on this platform."
+#endif
+#endif
+
+  return false;
+}
+
+
+inline bool LocalAddressSpace::findOtherFDE(pint_t targetAddr, pint_t &fde) {
+#ifdef __APPLE__
+  return checkKeyMgrRegisteredFDEs(targetAddr, *((void**)&fde));
+#else
+  // TO DO: if OS has way to dynamically register FDEs, check that.
+  (void)targetAddr;
+  (void)fde;
+  return false;
+#endif
+}
+
+inline bool LocalAddressSpace::findFunctionName(pint_t addr, char *buf,
+                                                size_t bufLen,
+                                                unw_word_t *offset) {
+#ifndef _LIBUNWIND_IS_BAREMETAL
+  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;
+    }
+  }
+#endif
+  return false;
+}
+
+
+
+#ifdef UNW_REMOTE
+
+/// OtherAddressSpace is used as a template parameter to UnwindCursor when
+/// unwinding a thread in the another process.  The other process can be a
+/// different endianness and a different pointer size which is handled by
+/// the P template parameter.
+template <typename P>
+class OtherAddressSpace {
+public:
+  OtherAddressSpace(task_t task) : fTask(task) {}
+
+  typedef typename P::uint_t pint_t;
+
+  uint8_t   get8(pint_t addr);
+  uint16_t  get16(pint_t addr);
+  uint32_t  get32(pint_t addr);
+  uint64_t  get64(pint_t addr);
+  pint_t    getP(pint_t addr);
+  uint64_t  getULEB128(pint_t &addr, pint_t end);
+  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);
+private:
+  void *localCopy(pint_t addr);
+
+  task_t fTask;
+};
+
+template <typename P> uint8_t OtherAddressSpace<P>::get8(pint_t addr) {
+  return *((uint8_t *)localCopy(addr));
+}
+
+template <typename P> uint16_t OtherAddressSpace<P>::get16(pint_t addr) {
+  return P::E::get16(*(uint16_t *)localCopy(addr));
+}
+
+template <typename P> uint32_t OtherAddressSpace<P>::get32(pint_t addr) {
+  return P::E::get32(*(uint32_t *)localCopy(addr));
+}
+
+template <typename P> uint64_t OtherAddressSpace<P>::get64(pint_t addr) {
+  return P::E::get64(*(uint64_t *)localCopy(addr));
+}
+
+template <typename P>
+typename P::uint_t OtherAddressSpace<P>::getP(pint_t addr) {
+  return P::getP(*(uint64_t *)localCopy(addr));
+}
+
+template <typename P>
+uint64_t OtherAddressSpace<P>::getULEB128(pint_t &addr, pint_t end) {
+  uintptr_t size = (end - addr);
+  LocalAddressSpace::pint_t laddr = (LocalAddressSpace::pint_t) localCopy(addr);
+  LocalAddressSpace::pint_t sladdr = laddr;
+  uint64_t result = LocalAddressSpace::getULEB128(laddr, laddr + size);
+  addr += (laddr - sladdr);
+  return result;
+}
+
+template <typename P>
+int64_t OtherAddressSpace<P>::getSLEB128(pint_t &addr, pint_t end) {
+  uintptr_t size = (end - addr);
+  LocalAddressSpace::pint_t laddr = (LocalAddressSpace::pint_t) localCopy(addr);
+  LocalAddressSpace::pint_t sladdr = laddr;
+  uint64_t result = LocalAddressSpace::getSLEB128(laddr, laddr + size);
+  addr += (laddr - sladdr);
+  return result;
+}
+
+template <typename P> void *OtherAddressSpace<P>::localCopy(pint_t addr) {
+  // FIX ME
+}
+
+template <typename P>
+bool OtherAddressSpace<P>::findFunctionName(pint_t addr, char *buf,
+                                            size_t bufLen, unw_word_t *offset) {
+  // FIX ME
+}
+
+/// unw_addr_space is the base class that abstract unw_addr_space_t type in
+/// libunwind.h points to.
+struct unw_addr_space {
+  cpu_type_t cpuType;
+  task_t taskPort;
+};
+
+/// unw_addr_space_i386 is the concrete instance that a unw_addr_space_t points
+/// to when examining
+/// a 32-bit intel process.
+struct unw_addr_space_i386 : public unw_addr_space {
+  unw_addr_space_i386(task_t task) : oas(task) {}
+  OtherAddressSpace<Pointer32<LittleEndian> > oas;
+};
+
+/// unw_addr_space_x86_64 is the concrete instance that a unw_addr_space_t
+/// points to when examining
+/// a 64-bit intel process.
+struct unw_addr_space_x86_64 : public unw_addr_space {
+  unw_addr_space_x86_64(task_t task) : oas(task) {}
+  OtherAddressSpace<Pointer64<LittleEndian> > oas;
+};
+
+/// unw_addr_space_ppc is the concrete instance that a unw_addr_space_t points
+/// to when examining
+/// a 32-bit PowerPC process.
+struct unw_addr_space_ppc : public unw_addr_space {
+  unw_addr_space_ppc(task_t task) : oas(task) {}
+  OtherAddressSpace<Pointer32<BigEndian> > oas;
+};
+
+#endif // UNW_REMOTE
+
+} // namespace libunwind
+
+#endif // __ADDRESSSPACE_HPP__