| /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 vi:set tabstop=4 expandtab: -*/ |
| //===-- UnwindLevel1-gcc-ext.c ----------------------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| /* |
| * Implements gcc extensions to the C++ ABI Exception Handling Level 1 as documented at: |
| * <http://www.codesourcery.com/cxx-abi/abi-eh.html> |
| * using libunwind |
| * |
| */ |
| |
| #include <stdint.h> |
| #include <stdbool.h> |
| #include <stdlib.h> |
| #include <stdio.h> |
| |
| #include "libunwind.h" |
| #include "unwind.h" |
| #include "libunwind_priv.h" |
| #include "InternalMacros.h" |
| |
| |
| #if __ppc__ || __i386__ || __x86_64__ |
| |
| // |
| // Called by __cxa_rethrow() |
| // |
| EXPORT _Unwind_Reason_Code _Unwind_Resume_or_Rethrow(struct _Unwind_Exception* exception_object) |
| { |
| DEBUG_PRINT_API("_Unwind_Resume_or_Rethrow(ex_obj=%p), private_1=%ld\n", exception_object, exception_object->private_1); |
| // if this is non-forced and a stopping place was found, then this is a re-throw |
| // call _Unwind_RaiseException() as if this was a new exception |
| if ( exception_object->private_1 == 0 ) |
| _Unwind_RaiseException(exception_object); |
| |
| // call through to _Unwind_Resume() which distiguishes between forced and regular exceptions |
| _Unwind_Resume(exception_object); |
| ABORT("_Unwind_Resume_or_Rethrow() called _Unwind_RaiseException() which unexpectedly returned"); |
| } |
| |
| |
| |
| // |
| // Called by personality handler during phase 2 to get base address for data relative encodings |
| // |
| EXPORT uintptr_t _Unwind_GetDataRelBase(struct _Unwind_Context* context) |
| { |
| DEBUG_PRINT_API("_Unwind_GetDataRelBase(context=%p)\n", context); |
| ABORT("_Unwind_GetDataRelBase() not implemented"); |
| } |
| |
| // |
| // Called by personality handler during phase 2 to get base address for text relative encodings |
| // |
| EXPORT uintptr_t _Unwind_GetTextRelBase(struct _Unwind_Context* context) |
| { |
| DEBUG_PRINT_API("_Unwind_GetTextRelBase(context=%p)\n", context); |
| ABORT("_Unwind_GetTextRelBase() not implemented"); |
| } |
| |
| |
| |
| // |
| // Scans unwind information to find the function that contains the |
| // specified code address "pc". |
| // |
| EXPORT void* _Unwind_FindEnclosingFunction(void* pc) |
| { |
| DEBUG_PRINT_API("_Unwind_FindEnclosingFunction(pc=%p)\n", pc); |
| ABORT("_Unwind_FindEnclosingFunction() not implemented"); |
| } |
| |
| |
| // |
| // Walk every frame and call trace function at each one. If trace function |
| // returns anything other than _URC_NO_REASON, then walk is terminated. |
| // |
| EXPORT _Unwind_Reason_Code _Unwind_Backtrace(_Unwind_Trace_Fn callback, void* ref) |
| { |
| unw_cursor_t cursor; |
| unw_context_t uc; |
| unw_getcontext(&uc); |
| unw_init_local(&cursor, &uc); |
| |
| DEBUG_PRINT_API("_Unwind_Backtrace(callback=%p)\n", callback); |
| |
| // walk each frame |
| while ( true ) { |
| |
| // ask libuwind to get next frame (skip over first frame which is _Unwind_Backtrace()) |
| if ( unw_step(&cursor) <= 0 ) { |
| DEBUG_PRINT_UNWINDING(" _backtrace: ended because cursor reached bottom of stack, returning %d\n", _URC_END_OF_STACK); |
| return _URC_END_OF_STACK; |
| } |
| |
| // debugging |
| if ( DEBUG_PRINT_UNWINDING_TEST ) { |
| char functionName[512]; |
| unw_proc_info_t frameInfo; |
| unw_word_t offset; |
| unw_get_proc_name(&cursor, functionName, 512, &offset); |
| unw_get_proc_info(&cursor, &frameInfo); |
| DEBUG_PRINT_UNWINDING(" _backtrace: start_ip=0x%llX, func=%s, lsda=0x%llX, context=%p\n", |
| frameInfo.start_ip, functionName, frameInfo.lsda, &cursor); |
| } |
| |
| // call trace function with this frame |
| _Unwind_Reason_Code result = (*callback)((struct _Unwind_Context*)(&cursor), ref); |
| if ( result != _URC_NO_REASON ) { |
| DEBUG_PRINT_UNWINDING(" _backtrace: ended because callback returned %d\n", result); |
| return result; |
| } |
| } |
| } |
| |
| |
| // |
| // Find dwarf unwind info for an address 'pc' in some function. |
| // |
| EXPORT const void* _Unwind_Find_FDE(const void* pc, struct dwarf_eh_bases* bases) |
| { |
| // This is slow, but works. |
| // We create an unwind cursor then alter the IP to be pc |
| unw_cursor_t cursor; |
| unw_context_t uc; |
| unw_proc_info_t info; |
| unw_getcontext(&uc); |
| unw_init_local(&cursor, &uc); |
| unw_set_reg(&cursor, UNW_REG_IP, (unw_word_t)(long)pc); |
| unw_get_proc_info(&cursor, &info); |
| bases->tbase = info.extra; |
| bases->dbase = 0; // dbase not used on Mac OS X |
| bases->func = info.start_ip; |
| DEBUG_PRINT_API("_Unwind_Find_FDE(pc=%p) => %p\n", pc, (void*)(long)info.unwind_info); |
| return (void*)(long)info.unwind_info; |
| } |
| |
| |
| |
| EXPORT uintptr_t _Unwind_GetCFA(struct _Unwind_Context* context) |
| { |
| unw_cursor_t* cursor = (unw_cursor_t*)context; |
| unw_word_t result; |
| unw_get_reg(cursor, UNW_REG_SP, &result); |
| DEBUG_PRINT_API("_Unwind_GetCFA(context=%p) => 0x%llX\n", context, (uint64_t)result); |
| return result; |
| } |
| |
| |
| // |
| // Called by personality handler during phase 2 to get instruction pointer. |
| // ipBefore is a boolean that says if IP is already adjusted to be the call |
| // site address. Normally IP is the return address. |
| // |
| EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context* context, int* ipBefore) |
| { |
| DEBUG_PRINT_API("_Unwind_GetIPInfo(context=%p)\n", context); |
| *ipBefore = 0; |
| return _Unwind_GetIP(context); |
| } |
| |
| |
| // |
| // Called by programs with dynamic code generators that want |
| // to register a dynamically generated FDE. |
| // This function has existed on Mac OS X since 10.4, but |
| // never worked before. |
| // |
| EXPORT void __register_frame(const void* fde) |
| { |
| DEBUG_PRINT_API("__register_frame(%p)\n", fde); |
| _unw_add_dynamic_fde((unw_word_t)(uintptr_t)fde); |
| } |
| |
| |
| // |
| // Called by programs with dynamic code generators that want |
| // to unregister a dynamically generated FDE. |
| // This function has existed on Mac OS X since 10.4, but |
| // never worked before. |
| // |
| EXPORT void __deregister_frame(const void* fde) |
| { |
| DEBUG_PRINT_API("__deregister_frame(%p)\n", fde); |
| _unw_remove_dynamic_fde((unw_word_t)(uintptr_t)fde); |
| } |
| |
| |
| |
| // |
| // The following register/deregister functions are gcc extensions. |
| // They have existed on Mac OS X, but have never worked because Mac OS X |
| // before 10.6 used keymgr to track known FDEs, but these functions |
| // never got updated to use keymgr. |
| // For now, we implement these as do-nothing functions to keep any existing |
| // applications working. We also add the not in 10.6 symbol so that nwe |
| // application won't be able to use them. |
| // |
| |
| EXPORT void __register_frame_info_bases(const void* fde, void* ob, void* tb, void* db) |
| { |
| DEBUG_PRINT_API("__register_frame_info_bases(%p,%p, %p, %p)\n", fde, ob, tb, db); |
| // do nothing, this function never worked in Mac OS X |
| } |
| |
| EXPORT void __register_frame_info(const void* fde, void* ob) |
| { |
| DEBUG_PRINT_API("__register_frame_info(%p, %p)\n", fde, ob); |
| // do nothing, this function never worked in Mac OS X |
| } |
| |
| |
| EXPORT void __register_frame_info_table_bases(const void* fde, void* ob, void* tb, void* db) |
| { |
| DEBUG_PRINT_API("__register_frame_info_table_bases(%p,%p, %p, %p)\n", fde, ob, tb, db); |
| // do nothing, this function never worked in Mac OS X |
| } |
| |
| EXPORT void __register_frame_info_table(const void* fde, void* ob) |
| { |
| DEBUG_PRINT_API("__register_frame_info_table(%p, %p)\n", fde, ob); |
| // do nothing, this function never worked in Mac OS X |
| } |
| |
| EXPORT void __register_frame_table(const void* fde) |
| { |
| DEBUG_PRINT_API("__register_frame_table(%p)\n", fde); |
| // do nothing, this function never worked in Mac OS X |
| } |
| |
| EXPORT void* __deregister_frame_info(const void* fde) |
| { |
| DEBUG_PRINT_API("__deregister_frame_info(%p)\n", fde); |
| // do nothing, this function never worked in Mac OS X |
| return NULL; |
| } |
| |
| EXPORT void* __deregister_frame_info_bases(const void* fde) |
| { |
| DEBUG_PRINT_API("__deregister_frame_info_bases(%p)\n", fde); |
| // do nothing, this function never worked in Mac OS X |
| return NULL; |
| } |
| |
| |
| |
| |
| // |
| // symbols in libSystem.dylib in 10.6 and later, but are in libgcc_s.dylib in earlier versions |
| // |
| NOT_HERE_BEFORE_10_6(_Unwind_Backtrace) |
| NOT_HERE_BEFORE_10_6(_Unwind_FindEnclosingFunction) |
| NOT_HERE_BEFORE_10_6(_Unwind_GetCFA) |
| NOT_HERE_BEFORE_10_6(_Unwind_GetDataRelBase) |
| NOT_HERE_BEFORE_10_6(_Unwind_GetTextRelBase) |
| NOT_HERE_BEFORE_10_6(_Unwind_Resume_or_Rethrow) |
| NOT_HERE_BEFORE_10_6(_Unwind_GetIPInfo) |
| |
| NOT_HERE_BEFORE_10_6(__register_frame) |
| NOT_HERE_BEFORE_10_6(__deregister_frame) |
| |
| |
| // |
| // symbols in libSystem.dylib for compatibility, but we don't want any new code using them |
| // |
| NEVER_HERE(__register_frame_info_bases) |
| NEVER_HERE(__register_frame_info) |
| NEVER_HERE(__register_frame_info_table_bases) |
| NEVER_HERE(__register_frame_info_table) |
| NEVER_HERE(__register_frame_table) |
| NEVER_HERE(__deregister_frame_info) |
| NEVER_HERE(__deregister_frame_info_bases) |
| |
| |
| #endif // __ppc__ || __i386__ || __x86_64__ |
| |