diff options
| -rw-r--r-- | libunwind/src/AddressSpace.hpp | 20 | ||||
| -rw-r--r-- | libunwind/src/libunwind.cpp | 80 | ||||
| -rw-r--r-- | libunwind/src/libunwind_ext.h | 65 |
3 files changed, 165 insertions, 0 deletions
diff --git a/libunwind/src/AddressSpace.hpp b/libunwind/src/AddressSpace.hpp index 26d289068b38..1abbc8225468 100644 --- a/libunwind/src/AddressSpace.hpp +++ b/libunwind/src/AddressSpace.hpp @@ -66,6 +66,10 @@ char *getFuncNameFromTBTable(uintptr_t pc, uint16_t &NameLen, // In 10.7.0 or later, libSystem.dylib implements this function. extern "C" bool _dyld_find_unwind_sections(void *, dyld_unwind_sections *); +namespace libunwind { + bool findDynamicUnwindSections(void *, unw_dynamic_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 @@ -497,6 +501,22 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr, info.compact_unwind_section_length = (size_t)dyldInfo.compact_unwind_section_length; return true; } + + unw_dynamic_unwind_sections dynamicUnwindSectionInfo; + if (findDynamicUnwindSections((void *)targetAddr, + &dynamicUnwindSectionInfo)) { + info.dso_base = dynamicUnwindSectionInfo.dso_base; +#if defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) + info.dwarf_section = (uintptr_t)dynamicUnwindSectionInfo.dwarf_section; + info.dwarf_section_length = dynamicUnwindSectionInfo.dwarf_section_length; +#endif + info.compact_unwind_section = + (uintptr_t)dynamicUnwindSectionInfo.compact_unwind_section; + info.compact_unwind_section_length = + dynamicUnwindSectionInfo.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 diff --git a/libunwind/src/libunwind.cpp b/libunwind/src/libunwind.cpp index 0faea2b78570..1bd18659b786 100644 --- a/libunwind/src/libunwind.cpp +++ b/libunwind/src/libunwind.cpp @@ -349,7 +349,87 @@ void __unw_remove_dynamic_eh_frame_section(unw_word_t eh_frame_start) { #endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND) #endif // !defined(__USING_SJLJ_EXCEPTIONS__) +#ifdef __APPLE__ +namespace libunwind { + +static constexpr size_t MAX_DYNAMIC_UNWIND_SECTIONS_FINDERS = 8; + +static RWMutex findDynamicUnwindSectionsLock; +static size_t numDynamicUnwindSectionsFinders = 0; +static unw_find_dynamic_unwind_sections + dynamicUnwindSectionsFinders[MAX_DYNAMIC_UNWIND_SECTIONS_FINDERS] = {0}; + +bool findDynamicUnwindSections(void *addr, unw_dynamic_unwind_sections *info) { + bool found = false; + findDynamicUnwindSectionsLock.lock_shared(); + for (size_t i = 0; i != numDynamicUnwindSectionsFinders; ++i) { + if (dynamicUnwindSectionsFinders[i]((unw_word_t)addr, info)) { + found = true; + break; + } + } + findDynamicUnwindSectionsLock.unlock_shared(); + return found; +} + +} // namespace libunwind + +int __unw_add_find_dynamic_unwind_sections( + unw_find_dynamic_unwind_sections find_dynamic_unwind_sections) { + findDynamicUnwindSectionsLock.lock(); + + // Check that we have enough space... + if (numDynamicUnwindSectionsFinders == MAX_DYNAMIC_UNWIND_SECTIONS_FINDERS) { + findDynamicUnwindSectionsLock.unlock(); + return UNW_ENOMEM; + } + + // Check for value already present... + for (size_t i = 0; i != numDynamicUnwindSectionsFinders; ++i) { + if (dynamicUnwindSectionsFinders[i] == find_dynamic_unwind_sections) { + findDynamicUnwindSectionsLock.unlock(); + return UNW_EINVAL; + } + } + + // Success -- add callback entry. + dynamicUnwindSectionsFinders[numDynamicUnwindSectionsFinders++] = + find_dynamic_unwind_sections; + findDynamicUnwindSectionsLock.unlock(); + + return UNW_ESUCCESS; +} + +int __unw_remove_find_dynamic_unwind_sections( + unw_find_dynamic_unwind_sections find_dynamic_unwind_sections) { + findDynamicUnwindSectionsLock.lock(); + + // Find index to remove. + size_t finderIdx = numDynamicUnwindSectionsFinders; + for (size_t i = 0; i != numDynamicUnwindSectionsFinders; ++i) { + if (dynamicUnwindSectionsFinders[i] == find_dynamic_unwind_sections) { + finderIdx = i; + break; + } + } + + // If no such registration is present then error out. + if (finderIdx == numDynamicUnwindSectionsFinders) { + findDynamicUnwindSectionsLock.unlock(); + return UNW_EINVAL; + } + + // Remove entry. + for (size_t i = finderIdx; i != numDynamicUnwindSectionsFinders - 1; ++i) + dynamicUnwindSectionsFinders[i] = dynamicUnwindSectionsFinders[i + 1]; + dynamicUnwindSectionsFinders[--numDynamicUnwindSectionsFinders] = nullptr; + + findDynamicUnwindSectionsLock.unlock(); + return UNW_ESUCCESS; +} + +#endif // __APPLE__ // Add logging hooks in Debug builds only #ifndef NDEBUG diff --git a/libunwind/src/libunwind_ext.h b/libunwind/src/libunwind_ext.h index fdc533cb8962..28db43a4f6ee 100644 --- a/libunwind/src/libunwind_ext.h +++ b/libunwind/src/libunwind_ext.h @@ -58,6 +58,71 @@ extern void __unw_remove_dynamic_fde(unw_word_t fde); extern void __unw_add_dynamic_eh_frame_section(unw_word_t eh_frame_start); extern void __unw_remove_dynamic_eh_frame_section(unw_word_t eh_frame_start); +#ifdef __APPLE__ + +// Holds a description of the object-format-header (if any) and unwind info +// sections for a given address: +// +// * dso_base should point to a header for the JIT'd object containing the +// given address. The header's type should match the format type that +// libunwind was compiled for (so a mach_header or mach_header_64 on Darwin). +// A value of zero indicates that no such header exists. +// +// * dwarf_section and dwarf_section_length hold the address range of a DWARF +// eh-frame section associated with the given address, if any. If the +// dwarf_section_length field is zero it indicates that no such section +// exists (and in this case dwarf_section should also be set to zero). +// +// * compact_unwind_section and compact_unwind_section_length hold the address +// range of a compact-unwind info section associated with the given address, +// if any. If the compact_unwind_section_length field is zero it indicates +// that no such section exists (and in this case compact_unwind_section +// should also be set to zero). +// +// See the unw_find_dynamic_unwind_sections type below for more details. +struct unw_dynamic_unwind_sections { + unw_word_t dso_base; + unw_word_t dwarf_section; + size_t dwarf_section_length; + unw_word_t compact_unwind_section; + size_t compact_unwind_section_length; +}; + +// Typedef for unwind-info lookup callbacks. Functions of this type can be +// registered and deregistered using __unw_add_find_dynamic_unwind_sections +// and __unw_remove_find_dynamic_unwind_sections respectively. +// +// An unwind-info lookup callback should return 1 to indicate that it found +// unwind-info for the given address, or 0 to indicate that it did not find +// unwind-info for the given address. If found, the callback should populate +// some or all of the fields of the info argument (which is guaranteed to be +// non-null with all fields zero-initialized): +typedef int (*unw_find_dynamic_unwind_sections)( + unw_word_t addr, struct unw_dynamic_unwind_sections *info); + +// Register a dynamic unwind-info lookup callback. If libunwind does not find +// unwind info for a given frame in the executable program or normal dynamic +// shared objects then it will call all registered dynamic lookup functions +// in registration order until either one of them returns true, or the end +// of the list is reached. This lookup will happen before libunwind searches +// any eh-frames registered via __register_frame or +// __unw_add_dynamic_eh_frame_section. +// +// Returns UNW_ESUCCESS for successful registrations. If the given callback +// has already been registered then UNW_EINVAL will be returned. If all +// available callback entries are in use then UNW_ENOMEM will be returned. +extern int __unw_add_find_dynamic_unwind_sections( + unw_find_dynamic_unwind_sections find_dynamic_unwind_sections); + +// Deregister a dynacim unwind-info lookup callback. +// +// Returns UNW_ESUCCESS for successful deregistrations. If the given callback +// has already been registered then UNW_EINVAL will be returned. +extern int __unw_remove_find_dynamic_unwind_sections( + unw_find_dynamic_unwind_sections find_dynamic_unwind_sections); + +#endif + #if defined(_LIBUNWIND_ARM_EHABI) extern const uint32_t* decode_eht_entry(const uint32_t*, size_t*, size_t*); extern _Unwind_Reason_Code _Unwind_VRS_Interpret(_Unwind_Context *context, |