1 //===--------------------------- libuwind.cpp -----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
9 // Implements unw_* functions from <libunwind.h>
11 //===----------------------------------------------------------------------===//
13 #include <libunwind.h>
16 #include <cstdlib> // getenv
20 #include "libunwind_ext.h"
26 #if _LIBUNWIND_BUILD_ZERO_COST_APIS
28 #include "UnwindCursor.hpp"
30 using namespace libunwind;
32 /// internal object to represent this processes address space
33 LocalAddressSpace LocalAddressSpace::sThisAddressSpace;
35 /// record the registers and stack position of the caller
36 extern int unw_getcontext(unw_context_t *);
37 // note: unw_getcontext() implemented in assembly
39 /// Create a cursor of a thread in this process given 'context' recorded by
41 _LIBUNWIND_EXPORT int unw_init_local(unw_cursor_t *cursor,
42 unw_context_t *context) {
43 _LIBUNWIND_TRACE_API("unw_init_local(cursor=%p, context=%p)\n",
45 // Use "placement new" to allocate UnwindCursor in the cursor buffer.
47 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86>(
48 context, LocalAddressSpace::sThisAddressSpace);
50 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>(
51 context, LocalAddressSpace::sThisAddressSpace);
53 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_ppc>(
54 context, LocalAddressSpace::sThisAddressSpace);
56 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>(
57 context, LocalAddressSpace::sThisAddressSpace);
58 #elif LIBCXXABI_ARM_EHABI
59 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm>(
60 context, LocalAddressSpace::sThisAddressSpace);
62 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
63 co->setInfoBasedOnIPRegister();
70 _LIBUNWIND_EXPORT unw_addr_space_t unw_local_addr_space =
71 (unw_addr_space_t) & sThisAddressSpace;
73 /// Create a cursor into a thread in another process.
74 _LIBUNWIND_EXPORT int unw_init_remote_thread(unw_cursor_t *cursor,
77 // special case: unw_init_remote(xx, unw_local_addr_space, xx)
78 if (as == (unw_addr_space_t) & sThisAddressSpace)
79 return unw_init_local(cursor, NULL); //FIXME
81 // use "placement new" to allocate UnwindCursor in the cursor buffer
82 switch (as->cpuType) {
85 UnwindCursor<OtherAddressSpace<Pointer32<LittleEndian> >,
86 Registers_x86>(((unw_addr_space_i386 *)as)->oas, arg);
89 new ((void *)cursor) UnwindCursor<
90 OtherAddressSpace<Pointer64<LittleEndian> >, Registers_x86_64>(
91 ((unw_addr_space_x86_64 *)as)->oas, arg);
93 case CPU_TYPE_POWERPC:
95 UnwindCursor<OtherAddressSpace<Pointer32<BigEndian> >, Registers_ppc>(
96 ((unw_addr_space_ppc *)as)->oas, arg);
105 static bool is64bit(task_t task) {
106 return false; // FIXME
109 /// Create an address_space object for use in examining another task.
110 _LIBUNWIND_EXPORT unw_addr_space_t unw_create_addr_space_for_task(task_t task) {
113 unw_addr_space_x86_64 *as = new unw_addr_space_x86_64(task);
115 as->cpuType = CPU_TYPE_X86_64;
118 unw_addr_space_i386 *as = new unw_addr_space_i386(task);
120 as->cpuType = CPU_TYPE_I386;
129 /// Delete an address_space object.
130 _LIBUNWIND_EXPORT void unw_destroy_addr_space(unw_addr_space_t asp) {
131 switch (asp->cpuType) {
132 #if __i386__ || __x86_64__
133 case CPU_TYPE_I386: {
134 unw_addr_space_i386 *as = (unw_addr_space_i386 *)asp;
138 case CPU_TYPE_X86_64: {
139 unw_addr_space_x86_64 *as = (unw_addr_space_x86_64 *)asp;
144 case CPU_TYPE_POWERPC: {
145 unw_addr_space_ppc *as = (unw_addr_space_ppc *)asp;
154 /// Get value of specified register at cursor position in stack frame.
155 _LIBUNWIND_EXPORT int unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
157 _LIBUNWIND_TRACE_API("unw_get_reg(cursor=%p, regNum=%d, &value=%p)\n",
158 cursor, regNum, value);
159 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
160 if (co->validReg(regNum)) {
161 *value = co->getReg(regNum);
168 /// Set value of specified register at cursor position in stack frame.
169 _LIBUNWIND_EXPORT int unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
171 _LIBUNWIND_TRACE_API("unw_set_reg(cursor=%p, regNum=%d, value=0x%llX)\n",
172 cursor, regNum, (long long)value);
173 typedef LocalAddressSpace::pint_t pint_t;
174 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
175 if (co->validReg(regNum)) {
176 co->setReg(regNum, (pint_t)value);
177 // specical case altering IP to re-find info (being called by personality
179 if (regNum == UNW_REG_IP)
180 co->setInfoBasedOnIPRegister(false);
187 /// Get value of specified float register at cursor position in stack frame.
188 _LIBUNWIND_EXPORT int unw_get_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
189 unw_fpreg_t *value) {
190 _LIBUNWIND_TRACE_API("unw_get_fpreg(cursor=%p, regNum=%d, &value=%p)\n",
191 cursor, regNum, value);
192 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
193 if (co->validFloatReg(regNum)) {
194 *value = co->getFloatReg(regNum);
201 /// Set value of specified float register at cursor position in stack frame.
202 _LIBUNWIND_EXPORT int unw_set_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum,
204 #if LIBCXXABI_ARM_EHABI
205 _LIBUNWIND_TRACE_API("unw_set_fpreg(cursor=%p, regNum=%d, value=%llX)\n",
206 cursor, regNum, value);
208 _LIBUNWIND_TRACE_API("unw_set_fpreg(cursor=%p, regNum=%d, value=%g)\n",
209 cursor, regNum, value);
211 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
212 if (co->validFloatReg(regNum)) {
213 co->setFloatReg(regNum, value);
220 /// Move cursor to next frame.
221 _LIBUNWIND_EXPORT int unw_step(unw_cursor_t *cursor) {
222 _LIBUNWIND_TRACE_API("unw_step(cursor=%p)\n", cursor);
223 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
228 /// Get unwind info at cursor position in stack frame.
229 _LIBUNWIND_EXPORT int unw_get_proc_info(unw_cursor_t *cursor,
230 unw_proc_info_t *info) {
231 _LIBUNWIND_TRACE_API("unw_get_proc_info(cursor=%p, &info=%p)\n",
233 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
235 if (info->end_ip == 0)
242 /// Resume execution at cursor position (aka longjump).
243 _LIBUNWIND_EXPORT int unw_resume(unw_cursor_t *cursor) {
244 _LIBUNWIND_TRACE_API("unw_resume(cursor=%p)\n", cursor);
245 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
251 /// Get name of function at cursor position in stack frame.
252 _LIBUNWIND_EXPORT int unw_get_proc_name(unw_cursor_t *cursor, char *buf,
253 size_t bufLen, unw_word_t *offset) {
254 _LIBUNWIND_TRACE_API("unw_get_proc_name(cursor=%p, &buf=%p,"
255 "bufLen=%zu)\n", cursor, buf, bufLen);
256 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
257 if (co->getFunctionName(buf, bufLen, offset))
264 /// Checks if a register is a floating-point register.
265 _LIBUNWIND_EXPORT int unw_is_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum) {
266 _LIBUNWIND_TRACE_API("unw_is_fpreg(cursor=%p, regNum=%d)\n",
268 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
269 return co->validFloatReg(regNum);
273 /// Checks if a register is a floating-point register.
274 _LIBUNWIND_EXPORT const char *unw_regname(unw_cursor_t *cursor,
275 unw_regnum_t regNum) {
276 _LIBUNWIND_TRACE_API("unw_regname(cursor=%p, regNum=%d)\n",
278 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
279 return co->getRegisterName(regNum);
283 /// Checks if current frame is signal trampoline.
284 _LIBUNWIND_EXPORT int unw_is_signal_frame(unw_cursor_t *cursor) {
285 _LIBUNWIND_TRACE_API("unw_is_signal_frame(cursor=%p)\n", cursor);
286 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
287 return co->isSignalFrame();
291 // Save VFP registers d0-d15 using FSTMIADX instead of FSTMIADD
292 _LIBUNWIND_EXPORT void unw_save_vfp_as_X(unw_cursor_t *cursor) {
293 _LIBUNWIND_TRACE_API("unw_fpreg_save_vfp_as_X(cursor=%p)\n", cursor);
294 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
295 return co->saveVFPAsX();
300 #if _LIBUNWIND_SUPPORT_DWARF_UNWIND
301 /// SPI: walks cached dwarf entries
302 _LIBUNWIND_EXPORT void unw_iterate_dwarf_unwind_cache(void (*func)(
303 unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh)) {
304 _LIBUNWIND_TRACE_API("unw_iterate_dwarf_unwind_cache(func=%p)\n", func);
305 DwarfFDECache<LocalAddressSpace>::iterateCacheEntries(func);
309 /// IPI: for __register_frame()
310 void _unw_add_dynamic_fde(unw_word_t fde) {
311 CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
312 CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
313 const char *message = CFI_Parser<LocalAddressSpace>::decodeFDE(
314 LocalAddressSpace::sThisAddressSpace,
315 (LocalAddressSpace::pint_t) fde, &fdeInfo, &cieInfo);
316 if (message == NULL) {
317 // dynamically registered FDEs don't have a mach_header group they are in.
318 // Use fde as mh_group
319 unw_word_t mh_group = fdeInfo.fdeStart;
320 DwarfFDECache<LocalAddressSpace>::add((LocalAddressSpace::pint_t)mh_group,
321 fdeInfo.pcStart, fdeInfo.pcEnd,
324 _LIBUNWIND_DEBUG_LOG("_unw_add_dynamic_fde: bad fde: %s", message);
328 /// IPI: for __deregister_frame()
329 void _unw_remove_dynamic_fde(unw_word_t fde) {
330 // fde is own mh_group
331 DwarfFDECache<LocalAddressSpace>::removeAllIn((LocalAddressSpace::pint_t)fde);
333 #endif // _LIBUNWIND_SUPPORT_DWARF_UNWIND
335 #endif // _LIBUNWIND_BUILD_ZERO_COST_APIS
339 // Add logging hooks in Debug builds only
345 // do manual lock to avoid use of _cxa_guard_acquire or initializers
346 static bool checked = false;
347 static bool log = false;
349 log = (getenv("LIBUNWIND_PRINT_APIS") != NULL);
356 bool logUnwinding() {
357 // do manual lock to avoid use of _cxa_guard_acquire or initializers
358 static bool checked = false;
359 static bool log = false;
361 log = (getenv("LIBUNWIND_PRINT_UNWINDING") != NULL);