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diff --git a/src/UnwindLevel1.c b/src/UnwindLevel1.c
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+//===------------------------- UnwindLevel1.c -----------------------------===//
+//
+// 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.
+//
+//
+// Implements C++ ABI Exception Handling Level 1 as documented at:
+// http://mentorembedded.github.io/cxx-abi/abi-eh.html
+// using libunwind
+//
+//===----------------------------------------------------------------------===//
+
+// ARM EHABI does not specify _Unwind_{Get,Set}{GR,IP}(). Thus, we are
+// defining inline functions to delegate the function calls to
+// _Unwind_VRS_{Get,Set}(). However, some applications might declare the
+// function protetype directly (instead of including <unwind.h>), thus we need
+// to export these functions from libunwind.so as well.
+#define _LIBUNWIND_UNWIND_LEVEL1_EXTERNAL_LINKAGE 1
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "libunwind.h"
+#include "unwind.h"
+#include "config.h"
+
+#if !_LIBUNWIND_ARM_EHABI
+
+static _Unwind_Reason_Code
+unwind_phase1(unw_context_t *uc, _Unwind_Exception *exception_object) {
+ unw_cursor_t cursor1;
+ unw_init_local(&cursor1, uc);
+
+ // Walk each frame looking for a place to stop.
+ bool handlerNotFound = true;
+ while (handlerNotFound) {
+ // Ask libuwind to get next frame (skip over first which is
+ // _Unwind_RaiseException).
+ int stepResult = unw_step(&cursor1);
+ if (stepResult == 0) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_step() reached "
+ "bottom => _URC_END_OF_STACK\n",
+ (void *)exception_object);
+ return _URC_END_OF_STACK;
+ } else if (stepResult < 0) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_step failed => "
+ "_URC_FATAL_PHASE1_ERROR\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE1_ERROR;
+ }
+
+ // See if frame has code to run (has personality routine).
+ unw_proc_info_t frameInfo;
+ unw_word_t sp;
+ if (unw_get_proc_info(&cursor1, &frameInfo) != UNW_ESUCCESS) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase1(ex_ojb=%p): unw_get_proc_info "
+ "failed => _URC_FATAL_PHASE1_ERROR\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE1_ERROR;
+ }
+
+ // When tracing, print state information.
+ if (_LIBUNWIND_TRACING_UNWINDING) {
+ char functionBuf[512];
+ const char *functionName = functionBuf;
+ unw_word_t offset;
+ if ((unw_get_proc_name(&cursor1, functionBuf, sizeof(functionBuf),
+ &offset) != UNW_ESUCCESS) ||
+ (frameInfo.start_ip + offset > frameInfo.end_ip))
+ functionName = ".anonymous.";
+ unw_word_t pc;
+ unw_get_reg(&cursor1, UNW_REG_IP, &pc);
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase1(ex_ojb=%p): pc=0x%" PRIx64 ", start_ip=0x%" PRIx64
+ ", func=%s, lsda=0x%" PRIx64 ", personality=0x%" PRIx64 "\n",
+ (void *)exception_object, pc, frameInfo.start_ip, functionName,
+ frameInfo.lsda, frameInfo.handler);
+ }
+
+ // If there is a personality routine, ask it if it will want to stop at
+ // this frame.
+ if (frameInfo.handler != 0) {
+ __personality_routine p =
+ (__personality_routine)(long)(frameInfo.handler);
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase1(ex_ojb=%p): calling personality function %p\n",
+ (void *)exception_object, (void *)(uintptr_t)p);
+ _Unwind_Reason_Code personalityResult =
+ (*p)(1, _UA_SEARCH_PHASE, exception_object->exception_class,
+ exception_object, (struct _Unwind_Context *)(&cursor1));
+ switch (personalityResult) {
+ case _URC_HANDLER_FOUND:
+ // found a catch clause or locals that need destructing in this frame
+ // stop search and remember stack pointer at the frame
+ handlerNotFound = false;
+ unw_get_reg(&cursor1, UNW_REG_SP, &sp);
+ exception_object->private_2 = (uintptr_t)sp;
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase1(ex_ojb=%p): _URC_HANDLER_FOUND \n",
+ (void *)exception_object);
+ return _URC_NO_REASON;
+
+ case _URC_CONTINUE_UNWIND:
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase1(ex_ojb=%p): _URC_CONTINUE_UNWIND\n",
+ (void *)exception_object);
+ // continue unwinding
+ break;
+
+ default:
+ // something went wrong
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase1(ex_ojb=%p): _URC_FATAL_PHASE1_ERROR\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE1_ERROR;
+ }
+ }
+ }
+ return _URC_NO_REASON;
+}
+
+
+static _Unwind_Reason_Code
+unwind_phase2(unw_context_t *uc, _Unwind_Exception *exception_object) {
+ unw_cursor_t cursor2;
+ unw_init_local(&cursor2, uc);
+
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p)\n",
+ (void *)exception_object);
+
+ // Walk each frame until we reach where search phase said to stop.
+ while (true) {
+
+ // Ask libuwind to get next frame (skip over first which is
+ // _Unwind_RaiseException).
+ int stepResult = unw_step(&cursor2);
+ if (stepResult == 0) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step() reached "
+ "bottom => _URC_END_OF_STACK\n",
+ (void *)exception_object);
+ return _URC_END_OF_STACK;
+ } else if (stepResult < 0) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_step failed => "
+ "_URC_FATAL_PHASE1_ERROR\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+
+ // Get info about this frame.
+ unw_word_t sp;
+ unw_proc_info_t frameInfo;
+ unw_get_reg(&cursor2, UNW_REG_SP, &sp);
+ if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): unw_get_proc_info "
+ "failed => _URC_FATAL_PHASE1_ERROR\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+
+ // When tracing, print state information.
+ if (_LIBUNWIND_TRACING_UNWINDING) {
+ char functionBuf[512];
+ const char *functionName = functionBuf;
+ unw_word_t offset;
+ if ((unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf),
+ &offset) != UNW_ESUCCESS) ||
+ (frameInfo.start_ip + offset > frameInfo.end_ip))
+ functionName = ".anonymous.";
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): start_ip=0x%" PRIx64
+ ", func=%s, sp=0x%" PRIx64 ", lsda=0x%" PRIx64
+ ", personality=0x%" PRIx64 "\n",
+ (void *)exception_object, frameInfo.start_ip,
+ functionName, sp, frameInfo.lsda,
+ frameInfo.handler);
+ }
+
+ // If there is a personality routine, tell it we are unwinding.
+ if (frameInfo.handler != 0) {
+ __personality_routine p =
+ (__personality_routine)(long)(frameInfo.handler);
+ _Unwind_Action action = _UA_CLEANUP_PHASE;
+ if (sp == exception_object->private_2) {
+ // Tell personality this was the frame it marked in phase 1.
+ action = (_Unwind_Action)(_UA_CLEANUP_PHASE | _UA_HANDLER_FRAME);
+ }
+ _Unwind_Reason_Code personalityResult =
+ (*p)(1, action, exception_object->exception_class, exception_object,
+ (struct _Unwind_Context *)(&cursor2));
+ switch (personalityResult) {
+ case _URC_CONTINUE_UNWIND:
+ // Continue unwinding
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2(ex_ojb=%p): _URC_CONTINUE_UNWIND\n",
+ (void *)exception_object);
+ if (sp == exception_object->private_2) {
+ // Phase 1 said we would stop at this frame, but we did not...
+ _LIBUNWIND_ABORT("during phase1 personality function said it would "
+ "stop here, but now in phase2 it did not stop here");
+ }
+ break;
+ case _URC_INSTALL_CONTEXT:
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2(ex_ojb=%p): _URC_INSTALL_CONTEXT\n",
+ (void *)exception_object);
+ // Personality routine says to transfer control to landing pad.
+ // We may get control back if landing pad calls _Unwind_Resume().
+ if (_LIBUNWIND_TRACING_UNWINDING) {
+ unw_word_t pc;
+ unw_get_reg(&cursor2, UNW_REG_IP, &pc);
+ unw_get_reg(&cursor2, UNW_REG_SP, &sp);
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2(ex_ojb=%p): re-entering "
+ "user code with ip=0x%" PRIx64
+ ", sp=0x%" PRIx64 "\n",
+ (void *)exception_object, pc, sp);
+ }
+ unw_resume(&cursor2);
+ // unw_resume() only returns if there was an error.
+ return _URC_FATAL_PHASE2_ERROR;
+ default:
+ // Personality routine returned an unknown result code.
+ _LIBUNWIND_DEBUG_LOG("personality function returned unknown result %d",
+ personalityResult);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+ }
+ }
+
+ // Clean up phase did not resume at the frame that the search phase
+ // said it would...
+ return _URC_FATAL_PHASE2_ERROR;
+}
+
+static _Unwind_Reason_Code
+unwind_phase2_forced(unw_context_t *uc,
+ _Unwind_Exception *exception_object,
+ _Unwind_Stop_Fn stop, void *stop_parameter) {
+ unw_cursor_t cursor2;
+ unw_init_local(&cursor2, uc);
+
+ // Walk each frame until we reach where search phase said to stop
+ while (unw_step(&cursor2) > 0) {
+
+ // Update info about this frame.
+ unw_proc_info_t frameInfo;
+ if (unw_get_proc_info(&cursor2, &frameInfo) != UNW_ESUCCESS) {
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): unw_step "
+ "failed => _URC_END_OF_STACK\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+
+ // When tracing, print state information.
+ if (_LIBUNWIND_TRACING_UNWINDING) {
+ char functionBuf[512];
+ const char *functionName = functionBuf;
+ unw_word_t offset;
+ if ((unw_get_proc_name(&cursor2, functionBuf, sizeof(functionBuf),
+ &offset) != UNW_ESUCCESS) ||
+ (frameInfo.start_ip + offset > frameInfo.end_ip))
+ functionName = ".anonymous.";
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2_forced(ex_ojb=%p): start_ip=0x%" PRIx64
+ ", func=%s, lsda=0x%" PRIx64 ", personality=0x%" PRIx64 "\n",
+ (void *)exception_object, frameInfo.start_ip, functionName,
+ frameInfo.lsda, frameInfo.handler);
+ }
+
+ // Call stop function at each frame.
+ _Unwind_Action action =
+ (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE);
+ _Unwind_Reason_Code stopResult =
+ (*stop)(1, action, exception_object->exception_class, exception_object,
+ (struct _Unwind_Context *)(&cursor2), stop_parameter);
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2_forced(ex_ojb=%p): stop function returned %d\n",
+ (void *)exception_object, stopResult);
+ if (stopResult != _URC_NO_REASON) {
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2_forced(ex_ojb=%p): stopped by stop function\n",
+ (void *)exception_object);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+
+ // If there is a personality routine, tell it we are unwinding.
+ if (frameInfo.handler != 0) {
+ __personality_routine p =
+ (__personality_routine)(long)(frameInfo.handler);
+ _LIBUNWIND_TRACE_UNWINDING(
+ "unwind_phase2_forced(ex_ojb=%p): calling personality function %p\n",
+ (void *)exception_object, (void *)(uintptr_t)p);
+ _Unwind_Reason_Code personalityResult =
+ (*p)(1, action, exception_object->exception_class, exception_object,
+ (struct _Unwind_Context *)(&cursor2));
+ switch (personalityResult) {
+ case _URC_CONTINUE_UNWIND:
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+ "personality returned "
+ "_URC_CONTINUE_UNWIND\n",
+ (void *)exception_object);
+ // Destructors called, continue unwinding
+ break;
+ case _URC_INSTALL_CONTEXT:
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+ "personality returned "
+ "_URC_INSTALL_CONTEXT\n",
+ (void *)exception_object);
+ // We may get control back if landing pad calls _Unwind_Resume().
+ unw_resume(&cursor2);
+ break;
+ default:
+ // Personality routine returned an unknown result code.
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): "
+ "personality returned %d, "
+ "_URC_FATAL_PHASE2_ERROR\n",
+ (void *)exception_object, personalityResult);
+ return _URC_FATAL_PHASE2_ERROR;
+ }
+ }
+ }
+
+ // Call stop function one last time and tell it we've reached the end
+ // of the stack.
+ _LIBUNWIND_TRACE_UNWINDING("unwind_phase2_forced(ex_ojb=%p): calling stop "
+ "function with _UA_END_OF_STACK\n",
+ (void *)exception_object);
+ _Unwind_Action lastAction =
+ (_Unwind_Action)(_UA_FORCE_UNWIND | _UA_CLEANUP_PHASE | _UA_END_OF_STACK);
+ (*stop)(1, lastAction, exception_object->exception_class, exception_object,
+ (struct _Unwind_Context *)(&cursor2), stop_parameter);
+
+ // Clean up phase did not resume at the frame that the search phase said it
+ // would.
+ return _URC_FATAL_PHASE2_ERROR;
+}
+
+
+/// Called by __cxa_throw. Only returns if there is a fatal error.
+_LIBUNWIND_EXPORT _Unwind_Reason_Code
+_Unwind_RaiseException(_Unwind_Exception *exception_object) {
+ _LIBUNWIND_TRACE_API("_Unwind_RaiseException(ex_obj=%p)\n",
+ (void *)exception_object);
+ unw_context_t uc;
+ unw_getcontext(&uc);
+
+ // Mark that this is a non-forced unwind, so _Unwind_Resume()
+ // can do the right thing.
+ exception_object->private_1 = 0;
+ exception_object->private_2 = 0;
+
+ // phase 1: the search phase
+ _Unwind_Reason_Code phase1 = unwind_phase1(&uc, exception_object);
+ if (phase1 != _URC_NO_REASON)
+ return phase1;
+
+ // phase 2: the clean up phase
+ return unwind_phase2(&uc, exception_object);
+}
+
+
+
+/// When _Unwind_RaiseException() is in phase2, it hands control
+/// to the personality function at each frame. The personality
+/// may force a jump to a landing pad in that function, the landing
+/// pad code may then call _Unwind_Resume() to continue with the
+/// unwinding. Note: the call to _Unwind_Resume() is from compiler
+/// geneated user code. All other _Unwind_* routines are called
+/// by the C++ runtime __cxa_* routines.
+///
+/// Note: re-throwing an exception (as opposed to continuing the unwind)
+/// is implemented by having the code call __cxa_rethrow() which
+/// in turn calls _Unwind_Resume_or_Rethrow().
+_LIBUNWIND_EXPORT void
+_Unwind_Resume(_Unwind_Exception *exception_object) {
+ _LIBUNWIND_TRACE_API("_Unwind_Resume(ex_obj=%p)\n", (void *)exception_object);
+ unw_context_t uc;
+ unw_getcontext(&uc);
+
+ if (exception_object->private_1 != 0)
+ unwind_phase2_forced(&uc, exception_object,
+ (_Unwind_Stop_Fn) exception_object->private_1,
+ (void *)exception_object->private_2);
+ else
+ unwind_phase2(&uc, exception_object);
+
+ // Clients assume _Unwind_Resume() does not return, so all we can do is abort.
+ _LIBUNWIND_ABORT("_Unwind_Resume() can't return");
+}
+
+
+
+/// Not used by C++.
+/// Unwinds stack, calling "stop" function at each frame.
+/// Could be used to implement longjmp().
+_LIBUNWIND_EXPORT _Unwind_Reason_Code
+_Unwind_ForcedUnwind(_Unwind_Exception *exception_object,
+ _Unwind_Stop_Fn stop, void *stop_parameter) {
+ _LIBUNWIND_TRACE_API("_Unwind_ForcedUnwind(ex_obj=%p, stop=%p)\n",
+ (void *)exception_object, (void *)(uintptr_t)stop);
+ unw_context_t uc;
+ unw_getcontext(&uc);
+
+ // Mark that this is a forced unwind, so _Unwind_Resume() can do
+ // the right thing.
+ exception_object->private_1 = (uintptr_t) stop;
+ exception_object->private_2 = (uintptr_t) stop_parameter;
+
+ // do it
+ return unwind_phase2_forced(&uc, exception_object, stop, stop_parameter);
+}
+
+
+/// Called by personality handler during phase 2 to get LSDA for current frame.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_proc_info_t frameInfo;
+ uintptr_t result = 0;
+ if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+ result = (uintptr_t)frameInfo.lsda;
+ _LIBUNWIND_TRACE_API(
+ "_Unwind_GetLanguageSpecificData(context=%p) => 0x%" PRIxPTR "\n",
+ (void *)context, result);
+ if (result != 0) {
+ if (*((uint8_t *)result) != 0xFF)
+ _LIBUNWIND_DEBUG_LOG("lsda at 0x%" PRIxPTR " does not start with 0xFF\n",
+ result);
+ }
+ return result;
+}
+
+
+/// Called by personality handler during phase 2 to find the start of the
+/// function.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetRegionStart(struct _Unwind_Context *context) {
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_proc_info_t frameInfo;
+ uintptr_t result = 0;
+ if (unw_get_proc_info(cursor, &frameInfo) == UNW_ESUCCESS)
+ result = (uintptr_t)frameInfo.start_ip;
+ _LIBUNWIND_TRACE_API("_Unwind_GetRegionStart(context=%p) => 0x%" PRIxPTR "\n",
+ (void *)context, result);
+ return result;
+}
+
+
+/// Called by personality handler during phase 2 if a foreign exception
+// is caught.
+_LIBUNWIND_EXPORT void
+_Unwind_DeleteException(_Unwind_Exception *exception_object) {
+ _LIBUNWIND_TRACE_API("_Unwind_DeleteException(ex_obj=%p)\n",
+ (void *)exception_object);
+ if (exception_object->exception_cleanup != NULL)
+ (*exception_object->exception_cleanup)(_URC_FOREIGN_EXCEPTION_CAUGHT,
+ exception_object);
+}
+
+/// Called by personality handler during phase 2 to get register values.
+_LIBUNWIND_EXPORT uintptr_t
+_Unwind_GetGR(struct _Unwind_Context *context, int index) {
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_word_t result;
+ unw_get_reg(cursor, index, &result);
+ _LIBUNWIND_TRACE_API("_Unwind_GetGR(context=%p, reg=%d) => 0x%" PRIx64 "\n",
+ (void *)context, index, (uint64_t)result);
+ return (uintptr_t)result;
+}
+
+/// Called by personality handler during phase 2 to alter register values.
+_LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
+ uintptr_t value) {
+ _LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, reg=%d, value=0x%0" PRIx64
+ ")\n",
+ (void *)context, index, (uint64_t)value);
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_set_reg(cursor, index, value);
+}
+
+/// Called by personality handler during phase 2 to get instruction pointer.
+_LIBUNWIND_EXPORT uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_word_t result;
+ unw_get_reg(cursor, UNW_REG_IP, &result);
+ _LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIx64 "\n",
+ (void *)context, (uint64_t)result);
+ return (uintptr_t)result;
+}
+
+/// Called by personality handler during phase 2 to alter instruction pointer,
+/// such as setting where the landing pad is, so _Unwind_Resume() will
+/// start executing in the landing pad.
+_LIBUNWIND_EXPORT void _Unwind_SetIP(struct _Unwind_Context *context,
+ uintptr_t value) {
+ _LIBUNWIND_TRACE_API("_Unwind_SetIP(context=%p, value=0x%0" PRIx64 ")\n",
+ (void *)context, (uint64_t)value);
+ unw_cursor_t *cursor = (unw_cursor_t *)context;
+ unw_set_reg(cursor, UNW_REG_IP, value);
+}
+
+#endif // !_LIBUNWIND_ARM_EHABI