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>
17 #include "libunwind_ext.h"
21 #if _LIBUNWIND_BUILD_ZERO_COST_APIS
23 #include "UnwindCursor.hpp"
25 using namespace libunwind;
27 /// internal object to represent this processes address space
28 LocalAddressSpace LocalAddressSpace::sThisAddressSpace;
30 /// record the registers and stack position of the caller
31 extern int unw_getcontext(unw_context_t *);
32 // note: unw_getcontext() implemented in assembly
34 /// Create a cursor of a thread in this process given 'context' recorded by
36 _LIBUNWIND_EXPORT int unw_init_local(unw_cursor_t *cursor,
37 unw_context_t *context) {
38 _LIBUNWIND_TRACE_API("unw_init_local(cursor=%p, context=%p)\n",
40 // Use "placement new" to allocate UnwindCursor in the cursor buffer.
42 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86>(
43 context, LocalAddressSpace::sThisAddressSpace);
45 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>(
46 context, LocalAddressSpace::sThisAddressSpace);
48 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_ppc>(
49 context, LocalAddressSpace::sThisAddressSpace);
51 new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>(
52 context, LocalAddressSpace::sThisAddressSpace);
54 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
55 co->setInfoBasedOnIPRegister();
62 _LIBUNWIND_EXPORT unw_addr_space_t unw_local_addr_space =
63 (unw_addr_space_t) & sThisAddressSpace;
65 /// Create a cursor into a thread in another process.
66 _LIBUNWIND_EXPORT int unw_init_remote_thread(unw_cursor_t *cursor,
69 // special case: unw_init_remote(xx, unw_local_addr_space, xx)
70 if (as == (unw_addr_space_t) & sThisAddressSpace)
71 return unw_init_local(cursor, NULL); //FIXME
73 // use "placement new" to allocate UnwindCursor in the cursor buffer
74 switch (as->cpuType) {
77 UnwindCursor<OtherAddressSpace<Pointer32<LittleEndian> >,
78 Registers_x86>(((unw_addr_space_i386 *)as)->oas, arg);
81 new ((void *)cursor) UnwindCursor<
82 OtherAddressSpace<Pointer64<LittleEndian> >, Registers_x86_64>(
83 ((unw_addr_space_x86_64 *)as)->oas, arg);
85 case CPU_TYPE_POWERPC:
87 UnwindCursor<OtherAddressSpace<Pointer32<BigEndian> >, Registers_ppc>(
88 ((unw_addr_space_ppc *)as)->oas, arg);
97 static bool is64bit(task_t task) {
98 return false; // FIXME
101 /// Create an address_space object for use in examining another task.
102 _LIBUNWIND_EXPORT unw_addr_space_t unw_create_addr_space_for_task(task_t task) {
105 unw_addr_space_x86_64 *as = new unw_addr_space_x86_64(task);
107 as->cpuType = CPU_TYPE_X86_64;
110 unw_addr_space_i386 *as = new unw_addr_space_i386(task);
112 as->cpuType = CPU_TYPE_I386;
121 /// Delete an address_space object.
122 _LIBUNWIND_EXPORT void unw_destroy_addr_space(unw_addr_space_t asp) {
123 switch (asp->cpuType) {
124 #if __i386__ || __x86_64__
125 case CPU_TYPE_I386: {
126 unw_addr_space_i386 *as = (unw_addr_space_i386 *)asp;
130 case CPU_TYPE_X86_64: {
131 unw_addr_space_x86_64 *as = (unw_addr_space_x86_64 *)asp;
136 case CPU_TYPE_POWERPC: {
137 unw_addr_space_ppc *as = (unw_addr_space_ppc *)asp;
146 /// Get value of specified register at cursor position in stack frame.
147 _LIBUNWIND_EXPORT int unw_get_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
149 _LIBUNWIND_TRACE_API("unw_get_reg(cursor=%p, regNum=%d, &value=%p)\n",
150 cursor, regNum, value);
151 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
152 if (co->validReg(regNum)) {
153 *value = co->getReg(regNum);
160 /// Set value of specified register at cursor position in stack frame.
161 _LIBUNWIND_EXPORT int unw_set_reg(unw_cursor_t *cursor, unw_regnum_t regNum,
163 _LIBUNWIND_TRACE_API("unw_set_reg(cursor=%p, regNum=%d, value=0x%llX)\n",
164 cursor, regNum, value);
165 typedef LocalAddressSpace::pint_t pint_t;
166 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
167 if (co->validReg(regNum)) {
168 co->setReg(regNum, (pint_t)value);
169 // specical case altering IP to re-find info (being called by personality
171 if (regNum == UNW_REG_IP) {
172 unw_proc_info_t info;
174 pint_t orgArgSize = (pint_t)info.gp;
175 uint64_t orgFuncStart = info.start_ip;
176 co->setInfoBasedOnIPRegister(false);
177 // and adjust REG_SP if there was a DW_CFA_GNU_args_size
178 if ((orgFuncStart == info.start_ip) && (orgArgSize != 0))
179 co->setReg(UNW_REG_SP, co->getReg(UNW_REG_SP) + orgArgSize);
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 _LIBUNWIND_TRACE_API("unw_set_fpreg(cursor=%p, regNum=%d, value=%g)\n",
205 cursor, regNum, value);
206 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
207 if (co->validFloatReg(regNum)) {
208 co->setFloatReg(regNum, value);
215 /// Move cursor to next frame.
216 _LIBUNWIND_EXPORT int unw_step(unw_cursor_t *cursor) {
217 _LIBUNWIND_TRACE_API("unw_step(cursor=%p)\n", cursor);
218 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
223 /// Get unwind info at cursor position in stack frame.
224 _LIBUNWIND_EXPORT int unw_get_proc_info(unw_cursor_t *cursor,
225 unw_proc_info_t *info) {
226 _LIBUNWIND_TRACE_API("unw_get_proc_info(cursor=%p, &info=%p)\n",
228 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
230 if (info->end_ip == 0)
237 /// Resume execution at cursor position (aka longjump).
238 _LIBUNWIND_EXPORT int unw_resume(unw_cursor_t *cursor) {
239 _LIBUNWIND_TRACE_API("unw_resume(cursor=%p)\n", cursor);
240 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
246 /// Get name of function at cursor position in stack frame.
247 _LIBUNWIND_EXPORT int unw_get_proc_name(unw_cursor_t *cursor, char *buf,
248 size_t bufLen, unw_word_t *offset) {
249 _LIBUNWIND_TRACE_API("unw_get_proc_name(cursor=%p, &buf=%p,"
250 "bufLen=%ld)\n", cursor, buf, bufLen);
251 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
252 if (co->getFunctionName(buf, bufLen, offset))
259 /// Checks if a register is a floating-point register.
260 _LIBUNWIND_EXPORT int unw_is_fpreg(unw_cursor_t *cursor, unw_regnum_t regNum) {
261 _LIBUNWIND_TRACE_API("unw_is_fpreg(cursor=%p, regNum=%d)\n",
263 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
264 return co->validFloatReg(regNum);
268 /// Checks if a register is a floating-point register.
269 _LIBUNWIND_EXPORT const char *unw_regname(unw_cursor_t *cursor,
270 unw_regnum_t regNum) {
271 _LIBUNWIND_TRACE_API("unw_regname(cursor=%p, regNum=%d)\n",
273 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
274 return co->getRegisterName(regNum);
278 /// Checks if current frame is signal trampoline.
279 _LIBUNWIND_EXPORT int unw_is_signal_frame(unw_cursor_t *cursor) {
280 _LIBUNWIND_TRACE_API("unw_is_signal_frame(cursor=%p)\n", cursor);
281 AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
282 return co->isSignalFrame();
286 #if _LIBUNWIND_SUPPORT_DWARF_UNWIND
287 /// SPI: walks cached dwarf entries
288 _LIBUNWIND_EXPORT void unw_iterate_dwarf_unwind_cache(void (*func)(
289 unw_word_t ip_start, unw_word_t ip_end, unw_word_t fde, unw_word_t mh)) {
290 _LIBUNWIND_TRACE_API("unw_iterate_dwarf_unwind_cache(func=%p)\n", func);
291 DwarfFDECache<LocalAddressSpace>::iterateCacheEntries(func);
295 /// IPI: for __register_frame()
296 void _unw_add_dynamic_fde(unw_word_t fde) {
297 CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
298 CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
299 const char *message = CFI_Parser<LocalAddressSpace>::decodeFDE(
300 LocalAddressSpace::sThisAddressSpace,
301 (LocalAddressSpace::pint_t) fde, &fdeInfo, &cieInfo);
302 if (message == NULL) {
303 // dynamically registered FDEs don't have a mach_header group they are in.
304 // Use fde as mh_group
305 unw_word_t mh_group = fdeInfo.fdeStart;
306 DwarfFDECache<LocalAddressSpace>::add((LocalAddressSpace::pint_t)mh_group,
307 fdeInfo.pcStart, fdeInfo.pcEnd,
310 _LIBUNWIND_DEBUG_LOG("_unw_add_dynamic_fde: bad fde: %s", message);
314 /// IPI: for __deregister_frame()
315 void _unw_remove_dynamic_fde(unw_word_t fde) {
316 // fde is own mh_group
317 DwarfFDECache<LocalAddressSpace>::removeAllIn((LocalAddressSpace::pint_t)fde);
319 #endif // _LIBUNWIND_SUPPORT_DWARF_UNWIND
321 #endif // _LIBUNWIND_BUILD_ZERO_COST_APIS
325 // Add logging hooks in Debug builds only
330 // do manual lock to avoid use of _cxa_guard_acquire or initializers
331 static bool checked = false;
332 static bool log = false;
334 log = (getenv("LIBUNWIND_PRINT_APIS") != NULL);
341 bool logUnwinding() {
342 // do manual lock to avoid use of _cxa_guard_acquire or initializers
343 static bool checked = false;
344 static bool log = false;
346 log = (getenv("LIBUNWIND_PRINT_UNWINDING") != NULL);