libstdc++-v3/libsupc++/eh_arm.cc - gcc - Git at Google

 // -*- C++ -*- ARM specific Exception handling support routines.
 // Copyright (C) 2004-2021 Free Software Foundation, Inc.
 //
 // This file is part of GCC.
 //
 // GCC is free software; you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
 // the Free Software Foundation; either version 3, or (at your option)
 // any later version.
 //
 // GCC is distributed in the hope that it will be useful,
 // but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 // GNU General Public License for more details.
 //
 // Under Section 7 of GPL version 3, you are granted additional
 // permissions described in the GCC Runtime Library Exception, version
 // 3.1, as published by the Free Software Foundation.
 //
 // You should have received a copy of the GNU General Public License and
 // a copy of the GCC Runtime Library Exception along with this program;
 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 // <http://www.gnu.org/licenses/>.

 #include <cxxabi.h>
 #include "unwind-cxx.h"

 #ifdef __ARM_EABI_UNWINDER__

 using namespace __cxxabiv1;


 // Given the thrown type THROW_TYPE, exception object UE_HEADER and a
 // type CATCH_TYPE to compare against, return whether or not there is
 // a match and if so, update *THROWN_PTR_P to point to either the
 // type-matched object, or in the case of a pointer type, the object
 // pointed to by the pointer.

 extern "C" __cxa_type_match_result
 __cxa_type_match(_Unwind_Exception* ue_header,
 		 const std::type_info* catch_type,
 		 bool is_reference __attribute__((__unused__)),
 		 void** thrown_ptr_p)
 {
   bool forced_unwind
     = __is_gxx_forced_unwind_class(ue_header->exception_class);
   bool foreign_exception
     = !forced_unwind && !__is_gxx_exception_class(ue_header->exception_class);
   bool dependent_exception
     = __is_dependent_exception(ue_header->exception_class);
   __cxa_exception* xh = __get_exception_header_from_ue(ue_header);
   __cxa_dependent_exception *dx = __get_dependent_exception_from_ue(ue_header);
   const std::type_info* throw_type;
   void *thrown_ptr = 0;

   if (forced_unwind)
     throw_type = &typeid(abi::__forced_unwind);
   else if (foreign_exception)
     throw_type = &typeid(abi::__foreign_exception);
   else
     {
       if (dependent_exception)
 	xh = __get_exception_header_from_obj (dx->primaryException);
       throw_type = xh->exceptionType;
       // We used to require the caller set the target of thrown_ptr_p,
       // but that's incorrect -- the EHABI makes no such requirement
       // -- and not all callers will set it.  Fortunately callers that
       // do initialize will always pass us the value we calculate
       // here, so there's no backwards compatibility problem.
       thrown_ptr = __get_object_from_ue (ue_header);
     }

   __cxa_type_match_result result = ctm_succeeded;

   // Pointer types need to adjust the actual pointer, not
   // the pointer to pointer that is the exception object.
   // This also has the effect of passing pointer types
   // "by value" through the __cxa_begin_catch return value.
   if (throw_type->__is_pointer_p())
     {
       thrown_ptr = *(void**) thrown_ptr;
       // We need to indicate the indirection to our caller.
       result = ctm_succeeded_with_ptr_to_base;
     }

   if (catch_type->__do_catch(throw_type, &thrown_ptr, 1))
     {
       *thrown_ptr_p = thrown_ptr;
       return result;
     }

   return ctm_failed;
 }

 // ABI defined routine called at the start of a cleanup handler.
 extern "C" bool
 __cxa_begin_cleanup(_Unwind_Exception* ue_header)
 {
   __cxa_eh_globals *globals = __cxa_get_globals();
   __cxa_exception *header = __get_exception_header_from_ue(ue_header);
   bool native = __is_gxx_exception_class(header->unwindHeader.exception_class);


   if (native)
     {
       header->propagationCount++;
       // Add it to the chain if this is the first time we've seen this
       // exception.
       if (header->propagationCount == 1)
 	{
 	  header->nextPropagatingException = globals->propagatingExceptions;
 	  globals->propagatingExceptions = header;
 	}
     }
   else
     {
       // Remember the exception object, so end_cleanup can return it.
       // These cannot be stacked, so we must abort if we already have
       // a propagating exception.
       if (globals->propagatingExceptions)
 	std::terminate ();
       globals->propagatingExceptions = header;
     }

   return true;
 }

 // Do the work for __cxa_end_cleanup.  Returns the currently propagating
 // exception object.
 extern "C" _Unwind_Exception *
 __gnu_end_cleanup(void)
 {
   __cxa_exception *header;
   __cxa_eh_globals *globals = __cxa_get_globals();

   header = globals->propagatingExceptions;

   // Check something hasn't gone horribly wrong.
   if (!header)
     std::terminate();

   if (__is_gxx_exception_class(header->unwindHeader.exception_class))
     {
       header->propagationCount--;
       if (header->propagationCount == 0)
 	{
 	  // Remove exception from chain.
 	  globals->propagatingExceptions = header->nextPropagatingException;
 	  header->nextPropagatingException = NULL;
 	}
     }
   else
     globals->propagatingExceptions = NULL;

   return &header->unwindHeader;
 }

 #ifdef __TMS320C6X__
 // Assembly wrapper to call __gnu_end_cleanup without clobbering
 // function arguments to _Unwind_Resume.
 asm (".global __cxa_end_cleanup\n"
 "	.type __cxa_end_cleanup, \"function\"\n"
 "__cxa_end_cleanup:\n"
 "	stw	.d2t2	B9, *B15--[10]\n"
 "	stw	.d2t2	B8, *+B15[9]\n"
 "	stw	.d2t2	B7, *+B15[8]\n"
 "	stw	.d2t2	B6, *+B15[7]\n"
 "	stw	.d2t2	B5, *+B15[6]\n"
 "	stw	.d2t2	B4, *+B15[5]\n"
 "	stw	.d2t1	A9, *+B15[4]\n"
 "	stw	.d2t1	A8, *+B15[3]\n"
 "	stw	.d2t1	A7, *+B15[2]\n"
 "	stw	.d2t1	A6, *+B15[1]\n"
 #ifdef _TMS320C6400_PLUS
 "	callp	.s2	(__gnu_end_cleanup), B3\n"
 #elif defined(_TMS320C6400)
 "	call	.s2	(__gnu_end_cleanup)\n"
 "	addkpc	.s2	1f, B3, 0\n"
 "	nop		4\n"
 "1:\n"
 #else
 "	call	.s2	(__gnu_end_cleanup)\n"
 "	mvkl	.s2	1f, B3\n"
 "	mvkh	.s2	1f, B3\n"
 "	nop		3\n"
 "1:\n"
 #endif
 "	ldw	.d2t1	*+B15[1], A6\n"
 "	ldw	.d2t1	*+B15[2], A7\n"
 "	ldw	.d2t1	*+B15[3], A8\n"
 "	ldw	.d2t1	*+B15[4], A9\n"
 "	ldw	.d2t2	*+B15[5], B4\n"
 "	ldw	.d2t2	*+B15[6], B5\n"
 "	ldw	.d2t2	*+B15[7], B6\n"
 "	ldw	.d2t2	*+B15[8], B7\n"
 "	ldw	.d2t2	*+B15[9], B8\n"
 "	ldw	.d2t2	*++B15[10], B9\n"
 "	b	.s2	_Unwind_Resume\n"
 "	nop		5\n");
 #else
 // Assembly wrapper to call __gnu_end_cleanup without clobbering r1-r3.
 // Also push r4 to preserve stack alignment.
 #ifdef __thumb__
 asm ("  .pushsection .text.__cxa_end_cleanup\n"
 "	.global __cxa_end_cleanup\n"
 "	.type __cxa_end_cleanup, \"function\"\n"
 "	.thumb_func\n"
 "__cxa_end_cleanup:\n"
 "	push\t{r1, r2, r3, r4}\n"
 "	bl\t__gnu_end_cleanup\n"
 "	pop\t{r1, r2, r3, r4}\n"
 "	bl\t_Unwind_Resume @ Never returns\n"
 "	.popsection\n");
 #else
 asm ("  .pushsection .text.__cxa_end_cleanup\n"
 "	.global __cxa_end_cleanup\n"
 "	.type __cxa_end_cleanup, \"function\"\n"
 "__cxa_end_cleanup:\n"
 "	stmfd\tsp!, {r1, r2, r3, r4}\n"
 "	bl\t__gnu_end_cleanup\n"
 "	ldmfd\tsp!, {r1, r2, r3, r4}\n"
 "	bl\t_Unwind_Resume @ Never returns\n"
 "	.popsection\n");
 #endif
 #endif

 #endif
	// -- C++ -- ARM specific Exception handling support routines.
	// Copyright (C) 2004-2021 Free Software Foundation, Inc.
	//
	// This file is part of GCC.
	//
	// GCC is free software; you can redistribute it and/or modify
	// it under the terms of the GNU General Public License as published by
	// the Free Software Foundation; either version 3, or (at your option)
	// any later version.
	//
	// GCC is distributed in the hope that it will be useful,
	// but WITHOUT ANY WARRANTY; without even the implied warranty of
	// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	// GNU General Public License for more details.
	//
	// Under Section 7 of GPL version 3, you are granted additional
	// permissions described in the GCC Runtime Library Exception, version
	// 3.1, as published by the Free Software Foundation.
	//
	// You should have received a copy of the GNU General Public License and
	// a copy of the GCC Runtime Library Exception along with this program;
	// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
	// <http://www.gnu.org/licenses/>.

	#include <cxxabi.h>
	#include "unwind-cxx.h"

	#ifdef __ARM_EABI_UNWINDER__

	using namespace __cxxabiv1;


	// Given the thrown type THROW_TYPE, exception object UE_HEADER and a
	// type CATCH_TYPE to compare against, return whether or not there is
	// a match and if so, update *THROWN_PTR_P to point to either the
	// type-matched object, or in the case of a pointer type, the object
	// pointed to by the pointer.

	extern "C" __cxa_type_match_result
	__cxa_type_match(_Unwind_Exception* ue_header,
	const std::type_info* catch_type,
	bool is_reference __attribute__((__unused__)),
	void** thrown_ptr_p)
	{
	bool forced_unwind
	= __is_gxx_forced_unwind_class(ue_header->exception_class);
	bool foreign_exception
	= !forced_unwind && !__is_gxx_exception_class(ue_header->exception_class);
	bool dependent_exception
	= __is_dependent_exception(ue_header->exception_class);
	__cxa_exception* xh = __get_exception_header_from_ue(ue_header);
	__cxa_dependent_exception *dx = __get_dependent_exception_from_ue(ue_header);
	const std::type_info* throw_type;
	void *thrown_ptr = 0;

	if (forced_unwind)
	throw_type = &typeid(abi::__forced_unwind);
	else if (foreign_exception)
	throw_type = &typeid(abi::__foreign_exception);
	else
	{
	if (dependent_exception)
	xh = __get_exception_header_from_obj (dx->primaryException);
	throw_type = xh->exceptionType;
	// We used to require the caller set the target of thrown_ptr_p,
	// but that's incorrect -- the EHABI makes no such requirement
	// -- and not all callers will set it. Fortunately callers that
	// do initialize will always pass us the value we calculate
	// here, so there's no backwards compatibility problem.
	thrown_ptr = __get_object_from_ue (ue_header);
	}

	__cxa_type_match_result result = ctm_succeeded;

	// Pointer types need to adjust the actual pointer, not
	// the pointer to pointer that is the exception object.
	// This also has the effect of passing pointer types
	// "by value" through the __cxa_begin_catch return value.
	if (throw_type->__is_pointer_p())
	{
	thrown_ptr = (void*) thrown_ptr;
	// We need to indicate the indirection to our caller.
	result = ctm_succeeded_with_ptr_to_base;
	}

	if (catch_type->__do_catch(throw_type, &thrown_ptr, 1))
	{
	*thrown_ptr_p = thrown_ptr;
	return result;
	}

	return ctm_failed;
	}

	// ABI defined routine called at the start of a cleanup handler.
	extern "C" bool
	__cxa_begin_cleanup(_Unwind_Exception* ue_header)
	{
	__cxa_eh_globals *globals = __cxa_get_globals();
	__cxa_exception *header = __get_exception_header_from_ue(ue_header);
	bool native = __is_gxx_exception_class(header->unwindHeader.exception_class);


	if (native)
	{
	header->propagationCount++;
	// Add it to the chain if this is the first time we've seen this
	// exception.
	if (header->propagationCount == 1)
	{
	header->nextPropagatingException = globals->propagatingExceptions;
	globals->propagatingExceptions = header;
	}
	}
	else
	{
	// Remember the exception object, so end_cleanup can return it.
	// These cannot be stacked, so we must abort if we already have
	// a propagating exception.
	if (globals->propagatingExceptions)
	std::terminate ();
	globals->propagatingExceptions = header;
	}

	return true;
	}

	// Do the work for __cxa_end_cleanup. Returns the currently propagating
	// exception object.
	extern "C" _Unwind_Exception *
	__gnu_end_cleanup(void)
	{
	__cxa_exception *header;
	__cxa_eh_globals *globals = __cxa_get_globals();

	header = globals->propagatingExceptions;

	// Check something hasn't gone horribly wrong.
	if (!header)
	std::terminate();

	if (__is_gxx_exception_class(header->unwindHeader.exception_class))
	{
	header->propagationCount--;
	if (header->propagationCount == 0)
	{
	// Remove exception from chain.
	globals->propagatingExceptions = header->nextPropagatingException;
	header->nextPropagatingException = NULL;
	}
	}
	else
	globals->propagatingExceptions = NULL;

	return &header->unwindHeader;
	}

	#ifdef __TMS320C6X__
	// Assembly wrapper to call __gnu_end_cleanup without clobbering
	// function arguments to _Unwind_Resume.
	asm (".global __cxa_end_cleanup\n"
	" .type __cxa_end_cleanup, \"function\"\n"
	"__cxa_end_cleanup:\n"
	" stw .d2t2 B9, *B15--[10]\n"
	" stw .d2t2 B8, *+B15[9]\n"
	" stw .d2t2 B7, *+B15[8]\n"
	" stw .d2t2 B6, *+B15[7]\n"
	" stw .d2t2 B5, *+B15[6]\n"
	" stw .d2t2 B4, *+B15[5]\n"
	" stw .d2t1 A9, *+B15[4]\n"
	" stw .d2t1 A8, *+B15[3]\n"
	" stw .d2t1 A7, *+B15[2]\n"
	" stw .d2t1 A6, *+B15[1]\n"
	#ifdef _TMS320C6400_PLUS
	" callp .s2 (__gnu_end_cleanup), B3\n"
	#elif defined(_TMS320C6400)
	" call .s2 (__gnu_end_cleanup)\n"
	" addkpc .s2 1f, B3, 0\n"
	" nop 4\n"
	"1:\n"
	#else
	" call .s2 (__gnu_end_cleanup)\n"
	" mvkl .s2 1f, B3\n"
	" mvkh .s2 1f, B3\n"
	" nop 3\n"
	"1:\n"
	#endif
	" ldw .d2t1 *+B15[1], A6\n"
	" ldw .d2t1 *+B15[2], A7\n"
	" ldw .d2t1 *+B15[3], A8\n"
	" ldw .d2t1 *+B15[4], A9\n"
	" ldw .d2t2 *+B15[5], B4\n"
	" ldw .d2t2 *+B15[6], B5\n"
	" ldw .d2t2 *+B15[7], B6\n"
	" ldw .d2t2 *+B15[8], B7\n"
	" ldw .d2t2 *+B15[9], B8\n"
	" ldw .d2t2 *++B15[10], B9\n"
	" b .s2 _Unwind_Resume\n"
	" nop 5\n");
	#else
	// Assembly wrapper to call __gnu_end_cleanup without clobbering r1-r3.
	// Also push r4 to preserve stack alignment.
	#ifdef __thumb__
	asm (" .pushsection .text.__cxa_end_cleanup\n"
	" .global __cxa_end_cleanup\n"
	" .type __cxa_end_cleanup, \"function\"\n"
	" .thumb_func\n"
	"__cxa_end_cleanup:\n"
	" push\t{r1, r2, r3, r4}\n"
	" bl\t__gnu_end_cleanup\n"
	" pop\t{r1, r2, r3, r4}\n"
	" bl\t_Unwind_Resume @ Never returns\n"
	" .popsection\n");
	#else
	asm (" .pushsection .text.__cxa_end_cleanup\n"
	" .global __cxa_end_cleanup\n"
	" .type __cxa_end_cleanup, \"function\"\n"
	"__cxa_end_cleanup:\n"
	" stmfd\tsp!, {r1, r2, r3, r4}\n"
	" bl\t__gnu_end_cleanup\n"
	" ldmfd\tsp!, {r1, r2, r3, r4}\n"
	" bl\t_Unwind_Resume @ Never returns\n"
	" .popsection\n");
	#endif
	#endif

	#endif