--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/compsupp/aehabi/cppsemantics.cpp Thu Dec 17 09:24:54 2009 +0200
@@ -0,0 +1,1311 @@
+/* The C++ exceptions runtime support
+ *
+ * Copyright 2002-2003 ARM Limited.
+ */
+/*
+ Licence
+
+ 1. Subject to the provisions of clause 2, ARM hereby grants to LICENSEE a
+ perpetual, non-exclusive, nontransferable, royalty free, worldwide licence
+ to use this Example Implementation of Exception Handling solely for the
+ purpose of developing, having developed, manufacturing, having
+ manufactured, offering to sell, selling, supplying or otherwise
+ distributing products which comply with the Exception Handling ABI for the
+ ARM Architecture specification. All other rights are reserved to ARM or its
+ licensors.
+
+ 2. THIS EXAMPLE IMPLEMENTATION OF EXCEPTION HANDLING IS PROVIDED "AS IS"
+ WITH NO WARRANTIES EXPRESS, IMPLIED OR STATUTORY, INCLUDING BUT NOT LIMITED
+ TO ANY WARRANTY OF SATISFACTORY QUALITY, MERCHANTABILITY, NONINFRINGEMENT
+ OR FITNESS FOR A PARTICULAR PURPOSE.
+*/
+/*
+ * RCS $Revision: 1.29.2.1 $
+ * Checkin $Date: 2004/01/20 15:11:16 $
+ * Revising $Author: achapman $
+ */
+
+/* This source file is compiled automatically by ARM's make system into
+ * multiple object files. The source regions constituting object file
+ * xxx.o are delimited by ifdef xxx_c / endif directives.
+ *
+ * The source regions currently marked are:
+ * arm_exceptions_globs_c
+ * arm_exceptions_mem_c
+ * arm_exceptions_uncaught_c
+ * arm_exceptions_terminate_c
+ * arm_exceptions_setterminate_c
+ * arm_exceptions_unexpected_c
+ * arm_exceptions_setunexpected_c
+ * arm_exceptions_support_c
+ * arm_exceptions_callterm_c
+ * arm_exceptions_callunex_c
+ * arm_exceptions_currenttype_c
+ * arm_exceptions_alloc_c
+ * arm_exceptions_free_c
+ * arm_exceptions_throw_c
+ * arm_exceptions_rethrow_c
+ * arm_exceptions_foreign_c
+ * arm_exceptions_cleanup_c
+ * arm_exceptions_begincatch_c
+ * arm_exceptions_endcatch_c
+ * arm_exceptions_bad_typeid_c
+ * arm_exceptions_bad_cast_c
+ */
+
+#include <string.h>
+#include <typeinfo>
+#include <exception>
+#include <new>
+// Environment:
+#include "unwind_env.h"
+// Language-independent unwinder declarations:
+#include "unwinder.h"
+
+/* By default, none of these routines are unwindable: */
+#pragma noexceptions_unwind
+
+/* For brevity: */
+
+typedef _Unwind_Control_Block UCB;
+
+using std::terminate_handler;
+using std::unexpected_handler;
+using std::terminate;
+using std::unexpected;
+using std::type_info;
+
+/* Redeclare these interface routines as weak, so using them does not
+ * pull in the unwind library. We only want the unwind library if
+ * someone throws (or raises an exception from some other language).
+ */
+WEAKDECL NORETURNDECL void _Unwind_Resume(UCB *);
+WEAKDECL void _Unwind_Complete(UCB *);
+
+/* Diagnostics:
+ * Define DEBUG to get extra interfaces which assist debugging this functionality.
+ * Define PRINTED_DIAGNOSTICS for printed diagnostics.
+ */
+#ifdef DEBUG
+#define PRINTED_DIAGNOSTICS
+#endif
+
+#ifdef PRINTED_DIAGNOSTICS
+extern "C" int printf(const char *, ...);
+#endif
+
+/* --------- "Exceptions_class" string for our implementation: --------- */
+
+#define EXCEPTIONS_CLASS_SIZE 8
+#define ARMCPP_EXCEPTIONS_CLASS "ARM\0C++\0"
+
+
+/* --------- Exception control object: --------- */
+
+// Type __cxa_exception is the combined C++ housekeeping (LEO) and UCB.
+// It will be followed by the user exception object, hence must ensure
+// the latter is aligned on an 8 byte boundary.
+
+struct __cxa_exception {
+ const type_info *exceptionType; // RTTI object describing the type of the exception
+ void *(*exceptionDestructor)(void *); // Destructor for the exception object (may be NULL)
+ unexpected_handler unexpectedHandler; // Handler in force after evaluating throw expr
+ terminate_handler terminateHandler; // Handler in force after evaluating throw expr
+ __cxa_exception *nextCaughtException; // Chain of "currently caught" c++ exception objects
+ uint32_t handlerCount; // Count of how many handlers this EO is "caught" in
+ __cxa_exception *nextPropagatingException; // Chain of objects saved over cleanup
+ uint32_t propagationCount; // Count of live propagations (throws) of this EO
+ UCB ucb; // Forces alignment of next item to 8-byte boundary
+};
+
+
+/* --------- Control "globals": --------- */
+
+// We do this by putting all the thread-specific "globals" into a single
+// area of store, which we allocate space for dynamically.
+// We don't define a constructor for this; see comments with __cxa_get_globals.
+
+typedef void (*handler)(void);
+
+struct __cxa_eh_globals {
+ uint32_t uncaughtExceptions; // counter
+ unexpected_handler unexpectedHandler; // per-thread handler
+ terminate_handler terminateHandler; // per-thread handler
+ bool implementation_ever_called_terminate; // true if it ever did
+ handler call_hook; // transient field to tell terminate/unexpected which hook to call
+ __cxa_exception *caughtExceptions; // chain of "caught" exceptions
+ __cxa_exception *propagatingExceptions; // chain of "propagating" (in cleanup) exceptions
+ void *emergency_buffer; // emergency buffer for when rest of heap full
+};
+
+
+/* ---------- Entry points: ---------- */
+
+/* There is a little type-delicacy required here as __cxa_throw takes a
+ * function pointer. Setting aside the problem of not being able to form
+ * a pointer to a destructor in C++, if we simply say extern "C" here
+ * then the function pointer will also have C linkage and will be a
+ * pointer to a C function. This causes problems when __cxa_throw is
+ * defined (unless we repeat the extern "C" at the definition site) because
+ * the fnptr in the definition gets C++ linkage, hence that __cxa_throw has
+ * a different signature to the declared one, and so the function we wanted
+ * doesn't get defined at all.
+ * Maybe it should just take a void * but this seems more honest.
+ */
+
+typedef void *(*cppdtorptr)(void *);
+
+extern "C" {
+
+ // Protocol routines called directly from application code
+
+ void *__cxa_allocate_exception(size_t size);
+ void __cxa_free_exception(void *);
+ WEAKDECL void __cxa_throw(void *, const type_info *, cppdtorptr);
+ void __cxa_rethrow(void);
+ void *__cxa_begin_catch(UCB *);
+ void __cxa_end_catch(void);
+ void __cxa_end_cleanup(void);
+ const type_info *__cxa_current_exception_type(void);
+
+ // Protocol routines usually called only by the personality routine(s).
+
+ void __cxa_call_terminate(UCB *);
+ void __cxa_call_unexpected(UCB *);
+ bool __cxa_begin_cleanup(UCB *);
+ bool __cxa_type_match(UCB *, const std::type_info *, void **);
+
+ // Auxilliary routines
+
+ __cxa_eh_globals *__cxa_get_globals(void);
+ void __cxa_bad_typeid(void);
+ void __cxa_bad_cast(void);
+
+ // Emergency memory buffer management routines
+
+ void *__ARM_exceptions_buffer_init(void);
+ void *__ARM_exceptions_buffer_allocate(void *, size_t);
+ void *__ARM_exceptions_buffer_free(void *, void *);
+}
+
+
+// Support routines
+
+#define NAMES __ARM
+namespace NAMES {
+ void default_unexpected_handler(void);
+ void call_terminate_handler(UCB *);
+ void eh_catch_semantics(UCB *);
+ bool is_foreign_exception(UCB *);
+ bool same_exceptions_class(const void *, const void *);
+ __cxa_exception *get_foreign_intermediary(__cxa_exception *, UCB *);
+}
+
+// Macro: convert ucb pointer to __cxa_exception pointer
+
+#define ucbp_to_ep(UCB_P) ((__cxa_exception *)((char *)(UCB_P) - offsetof(__cxa_exception, ucb)))
+
+
+#ifdef arm_exceptions_globs_c
+
+/* --------- Allocating and retrieving "globals": --------- */
+
+// The exception-handling globals should be allocated per-thread.
+// This is done here assuming the existance of a zero-initialised void*
+// pointer location obtainable by the macro EH_GLOBALS.
+
+// Default terminate handler:
+
+static void __default_terminate_handler(void) {
+ abort();
+}
+
+// If std::unexpected() is in the image, include a default handler for it:
+namespace NAMES { WEAKDECL void default_unexpected_handler(void); }
+
+// If this symbol is present, allocate an emergency buffer.
+// As we aren't allowed static data, make it a function
+extern "C" WEAKDECL void __ARM_exceptions_buffer_required(void);
+
+
+// __cxa_eh_globals returns the per-thread memory. There are several complications,
+// all of which relate to not touching the exceptions system while trying to
+// initialise it:
+// 1) We can't obtain memory by calling new or nothrow new as both of these use
+// exceptions internally, so we must use malloc
+// 2) We choose not to initialise the memory via placement new and a constructor,
+// since placement new is declared with an empty function exception specification,
+// which causes more of the exceptions system to always be pulled in.
+// 3) We can't call terminate, as terminate looks in the memory we are trying to
+// allocate.
+
+__cxa_eh_globals *__cxa_get_globals(void)
+{
+ __cxa_eh_globals *this_thread_globals = (__cxa_eh_globals *)(EH_GLOBALS);
+ if (this_thread_globals == NULL) {
+
+ // First call
+ // Obtain some memory: this is thread-safe provided malloc is.
+ this_thread_globals = (__cxa_eh_globals *)malloc(sizeof(__cxa_eh_globals));
+ if (this_thread_globals == NULL) abort(); // NOT terminate(), which calls this fn
+
+ // Save the pointer in the specially-provided location
+ EH_GLOBALS = this_thread_globals;
+
+ // Finally initialise the memory by hand
+ this_thread_globals->uncaughtExceptions = 0;
+ this_thread_globals->unexpectedHandler = NAMES::default_unexpected_handler;
+ this_thread_globals->terminateHandler = __default_terminate_handler;
+ this_thread_globals->implementation_ever_called_terminate = false;
+ this_thread_globals->call_hook = NULL;
+ this_thread_globals->caughtExceptions = NULL;
+ this_thread_globals->propagatingExceptions = NULL;
+ if (&__ARM_exceptions_buffer_required == NULL)
+ this_thread_globals->emergency_buffer = NULL;
+ else
+ this_thread_globals->emergency_buffer = __ARM_exceptions_buffer_init();
+ }
+
+ return this_thread_globals;
+}
+
+
+#endif /* arm_exceptions_globs_c */
+#ifdef arm_exceptions_mem_c
+
+/* --------- Emergency memory: --------- */
+
+// It is possible to reserve memory for throwing bad_alloc when the heap
+// is otherwise full. The ARM implementation provides hooks to do this.
+// The default implementation reserves just enough space for a bad_alloc
+// object, so if memory is later exhausted bad_alloc can still be thrown.
+// Note there is no guarantee or requirement that the exception being
+// thrown is actually bad_alloc.
+
+// A usage flag and enough space for a bad_alloc exception control object
+
+struct emergency_eco {
+ __cxa_exception ep;
+ std::bad_alloc b;
+};
+
+struct emergency_buffer {
+ bool inuse;
+ struct emergency_eco eco;
+};
+
+// Initialiser
+void* __ARM_exceptions_buffer_init(void)
+{
+ emergency_buffer *buffer = (emergency_buffer *)malloc(sizeof(emergency_buffer));
+ if (buffer == NULL) return NULL;
+ buffer->inuse = false;
+ return buffer;
+}
+
+// Allocator
+void *__ARM_exceptions_buffer_allocate(void *buffer, size_t size)
+{
+ emergency_buffer *b = (emergency_buffer *)buffer;
+ if (size > sizeof(emergency_eco) || b == NULL || b->inuse) return NULL;
+ b->inuse = true;
+ return &b->eco;
+}
+
+// Deallocator: Must return non-NULL if and only if it recognises
+// and releases the supplied object
+void *__ARM_exceptions_buffer_free(void *buffer, void *addr)
+{
+ emergency_buffer *b = (emergency_buffer *)buffer;
+ if (b == NULL || addr != &b->eco) return NULL;
+ b->inuse = false;
+ return b;
+}
+
+
+#endif /* arm_exceptions_mem_c */
+#ifdef arm_exceptions_uncaught_c
+
+/* ---- uncaught_exception() ---- */
+
+/* The EDG (and I think our) interpretation is that if the implementation
+ * ever called terminate(), uncaught_exception() should return true.
+ */
+
+bool std::uncaught_exception(void)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ return g->implementation_ever_called_terminate || g->uncaughtExceptions;
+}
+
+
+#endif /* arm_exceptions_uncaught_c */
+#ifdef arm_exceptions_terminate_c
+
+/* ---- terminate() etc ---- */
+
+/* The behaviour of terminate() must differ between calls by the
+ * implementation and calls by the application. This is achieved by having the
+ * implementation set call_hook immediately before the call to terminate().
+ * The hook called by terminate() should terminate the program without
+ * returning to the caller. There is no requirement for terminate() itself to
+ * intercept throws.
+ */
+
+void std::terminate(void)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+
+ if (g->call_hook != NULL) {
+ // Clear then call hook fn we were passed
+ handler call_hook = g->call_hook;
+ g->call_hook = NULL;
+ call_hook();
+ } else {
+ // Call global hook fn
+ g->terminateHandler();
+ }
+ // If hook fn returns:
+ abort();
+}
+
+
+#endif /* arm_exceptions_terminate_c */
+#ifdef arm_exceptions_setterminate_c
+
+terminate_handler std::set_terminate(terminate_handler h) throw()
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ terminate_handler old = g->terminateHandler;
+ g->terminateHandler = h;
+ return old;
+}
+
+
+#endif /* arm_exceptions_setterminate_c */
+#ifdef arm_exceptions_unexpected_c
+
+/* ---- unexpected() etc ---- */
+/* Comments as per terminate() */
+
+void NAMES::default_unexpected_handler(void) {
+ terminate();
+}
+
+#pragma exceptions_unwind
+
+void std::unexpected(void)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+
+ if (g->call_hook != NULL) {
+ // Clear then call hook fn we were passed
+ handler call_hook = g->call_hook;
+ g->call_hook = NULL;
+ call_hook();
+ } else {
+ // Call global hook fn
+ g->unexpectedHandler();
+ }
+
+ // If hook fn returns:
+ abort();
+}
+
+
+#endif /* arm_exceptions_unexpected_c */
+#ifdef arm_exceptions_setunexpected_c
+
+unexpected_handler std::set_unexpected(unexpected_handler h) throw()
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ unexpected_handler old = g->unexpectedHandler;
+ g->unexpectedHandler = h;
+ return old;
+}
+
+
+#endif /* arm_exceptions_setunexpected_c */
+#ifdef arm_exceptions_support_c
+
+/* ---------- Helper functions: ---------- */
+
+/* Two routines to determine whether two exceptions objects share a layout.
+ * This is determined by checking whether the UCB exception_class members
+ * are identical.
+ * In principle we could use memcmp to perform this check (the code is
+ * given below) but the check is quite frequent and so that is costly.
+ * Therefore for efficiency we make use of the fact that the UCB is
+ * word aligned, that the exception_class member is consequently
+ * word aligned within it, and that we know the size of the member.
+ * We take care elsewhere to only ever call the routines with pointers
+ * to word-aligned addresses.
+ */
+
+#if 0
+
+// Straightforward versions
+
+bool NAMES::same_exceptions_class(const void *ec1, const void *ec2)
+{
+ return memcmp(ec1, ec2, EXCEPTIONS_CLASS_SIZE) == 0; // identical
+}
+
+// One of our exception objects, or not?
+
+bool NAMES::is_foreign_exception(UCB *ucbp)
+{
+ return !NAMES::same_exceptions_class(&ucbp->exception_class, ARMCPP_EXCEPTIONS_CLASS);
+}
+
+#else
+
+// Faster versions
+
+bool NAMES::same_exceptions_class(const void *ec1, const void *ec2)
+{
+ uint32_t *ip1 = (uint32_t *)ec1;
+ uint32_t *ip2 = (uint32_t *)ec2;
+ return ip1[0] == ip2[0] && ip1[1] == ip2[1];
+}
+
+// One of our exception objects, or not?
+
+bool NAMES::is_foreign_exception(UCB *ucbp)
+{
+ // Need a word-aligned copy of the string
+ static const union {
+ const char s[EXCEPTIONS_CLASS_SIZE+1]; int dummy;
+ } is_foreign_exception_static = {ARMCPP_EXCEPTIONS_CLASS};
+ return !NAMES::same_exceptions_class(&ucbp->exception_class, &is_foreign_exception_static.s);
+}
+
+#endif
+
+
+#endif /* arm_exceptions_support_c */
+#ifdef arm_exceptions_callterm_c
+
+/* When the implementation wants to call terminate(), do the following:
+ * Mark the object as "caught" so it can be rethrown.
+ * Set the hook function for terminate() to call;
+ * Mark the fact that terminate() has been called by the implementation;
+ * We have to be careful - the implementation might encounter an error while
+ * unwinding a foreign exception, and also it is possible this might be
+ * called after failing to obtain a ucb.
+ */
+
+void NAMES::call_terminate_handler(UCB *ucbp)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+
+ if (ucbp == NULL) {
+ // Call global hook
+ g->call_hook = g->terminateHandler;
+ } else {
+ // Extract the hook to call
+ if (NAMES::is_foreign_exception(ucbp)) {
+ // Someone else's
+ g->call_hook = g->terminateHandler; // best we can do under the circumstances
+ } else {
+ // One of ours
+ __cxa_exception *ep = ucbp_to_ep(ucbp);
+ g->call_hook = ep->terminateHandler; // the one in force at the point of throw
+ }
+ }
+
+ g->implementation_ever_called_terminate = true;
+ terminate();
+ // never returns
+}
+
+
+void __cxa_call_terminate(UCB *ucbp)
+{
+ if (ucbp != NULL) // Record entry to (implicit) handler
+ __cxa_begin_catch(ucbp);
+
+ NAMES::call_terminate_handler(ucbp);
+ // never returns
+}
+
+
+#endif /* arm_exceptions_callterm_c */
+#ifdef arm_exceptions_callunex_c
+
+/* When the implementation wants to call unexpected(), do the following:
+ * Mark the object as "caught" so it can be rethrown.
+ * Set the hook function for unexpected() to call;
+ * Call unexpected and trap any throw to make sure it is acceptable.
+ * We have to be careful - the implementation might encounter an error while
+ * unwinding a foreign exception.
+ */
+
+#pragma exceptions_unwind
+
+void __cxa_call_unexpected(UCB *ucbp)
+{
+
+ // Extract data we will need from the barrier cache before
+ // anyone has a chance to overwrite it
+
+ uint32_t rtti_count = ucbp->barrier_cache.bitpattern[1];
+ uint32_t base = ucbp->barrier_cache.bitpattern[2];
+ uint32_t stride = ucbp->barrier_cache.bitpattern[3];
+ uint32_t rtti_offset_array_addr = ucbp->barrier_cache.bitpattern[4];
+
+ // Also get the globals here and the eop
+
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep = ucbp_to_ep(ucbp);
+
+#ifdef ARM_EXCEPTIONS_ENABLED
+ try {
+#endif
+
+ // Record entry to (implicit) handler
+
+ __cxa_begin_catch(ucbp);
+
+ // Now extract the hook to call
+
+ if (NAMES::is_foreign_exception(ucbp)) {
+ // Someone else's
+ g->call_hook = g->unexpectedHandler; // best we can do under the circumstances
+ } else {
+ // One of ours
+ g->call_hook = ep->unexpectedHandler; // the one in force at the point of throw
+ }
+ unexpected(); // never returns normally, but might throw something
+
+#ifdef ARM_EXCEPTIONS_ENABLED
+ } catch (...) {
+
+ // Unexpected() threw. This requires some delicacy.
+ // There are 2 possibilities:
+ // i) rethrow of the same object
+ // ii) throw of a new object
+ // Unexpected() is an implicit handler, and we manually called
+ // __cxa_begin_catch on the ingoing object. We need to call
+ // __cxa_end_catch on that object and, if the object is no longer
+ // being handled (possible in case ii), this will cause its destruction.
+ // The wrinkle is that in case ii the object is not on top of the catch
+ // stack because we just caught something else.
+
+ // Get hold of what was thrown (which we just caught).
+
+ __cxa_exception *epnew = g->caughtExceptions;
+
+ // Call __cxa_end_catch on the original object, taking care with the catch chain
+
+ if (epnew == ep) {
+ // rethrow - easy & safe - object is at top of chain and handlercount > 1
+ __cxa_end_catch();
+ } else {
+ // not rethrow - unchain the top (new) object, clean up the next one,
+ // and put the top object back
+
+ // unchain
+ g->caughtExceptions = epnew->nextCaughtException;
+ // assert g->caughtExceptions == ep now
+ // Decrement its handlercount (this might call a dtor if the count goes to 0,
+ // and the dtor might throw - if it does, just give up)
+ try {
+ __cxa_end_catch();
+ } catch(...) {
+ terminate();
+ }
+ // Chain back in
+ epnew->nextCaughtException = g->caughtExceptions;
+ g->caughtExceptions = epnew;
+ }
+
+ // See whether what was thrown is permitted, and in passing
+ // see if std::bad_exception is permitted
+
+ bool bad_exception_permitted = false;
+ uint32_t i;
+ for (i = 0; i < rtti_count; i++) {
+ void *matched_object;
+ const type_info *fnspec = (const type_info *)(*(uint32_t *)rtti_offset_array_addr + base);
+ if (__cxa_type_match(&(epnew->ucb), fnspec, &matched_object)) {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_call_unexpected: fnspec matched\n");
+#endif
+ throw; // got a match - propagate it
+ }
+ if (&typeid(std::bad_exception) == fnspec)
+ bad_exception_permitted = true;
+ rtti_offset_array_addr += stride;
+ }
+
+ // There was no match...
+ if (bad_exception_permitted) throw std::bad_exception(); // transmute
+
+ // Otherwise call epnew's terminate handler
+ NAMES::call_terminate_handler(&epnew->ucb);
+ }
+#endif
+}
+
+
+#endif /* arm_exceptions_callunex_c */
+#ifdef arm_exceptions_currenttype_c
+
+/* Yield the type of the currently handled exception, or null if none or the
+ * object is foreign.
+ */
+
+const type_info *__cxa_current_exception_type(void)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep = g->caughtExceptions;
+ if (ep == NULL || NAMES::is_foreign_exception(&ep->ucb)) return NULL;
+ return ep->exceptionType;
+}
+
+
+#endif /* arm_exceptions_currenttype_c */
+#ifdef arm_exceptions_alloc_c
+
+/* Allocate store for controlling an exception propagation */
+
+void *__cxa_allocate_exception(size_t size)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+
+ // Allocate store for a __cxa_exception header and the EO.
+ // Allocated store should be thread-safe and persistent, and must do
+ // something sensible if the allocation fails
+
+ size_t total_size = size + sizeof(__cxa_exception);
+ __cxa_exception *ep = (__cxa_exception *)malloc(total_size);
+ if (ep == NULL) {
+ // Try the emergency memory pool
+ ep = (__cxa_exception *)__ARM_exceptions_buffer_allocate(g->emergency_buffer, total_size);
+ if (ep == NULL) NAMES::call_terminate_handler(NULL);
+ }
+
+ UCB *ucbp = &ep->ucb;
+
+ // Initialise the UCB
+
+ memcpy(ucbp->exception_class, ARMCPP_EXCEPTIONS_CLASS, EXCEPTIONS_CLASS_SIZE);
+ ucbp->exception_cleanup = NULL; /* initialise properly before throwing */
+ ucbp->unwinder_cache.reserved1 = 0; /* required to do this */
+
+ // Initialise parts of the LEO, in case copy-construction of the EO results
+ // in a need to call terminate (via __cxa_call_terminate)
+
+ ep->handlerCount = 0; // Not in any handlers
+ ep->nextCaughtException = NULL; // Not in any handlers
+ ep->nextPropagatingException = NULL; // Not saved over cleanup
+ ep->propagationCount = 0; // Not propagating
+ ep->terminateHandler = g->terminateHandler; // Cache current terminate handler
+ ep->unexpectedHandler = g->unexpectedHandler; // Cache current unexpected handler
+
+ // Return pointer to the EO
+
+ return ep + 1;
+}
+
+
+#endif /* arm_exceptions_alloc_c */
+#ifdef arm_exceptions_free_c
+
+/* Free store allocated by __cxa_allocate_exception */
+
+void __cxa_free_exception(void *eop)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ char *ep = (char *)eop - sizeof(__cxa_exception);
+ if (__ARM_exceptions_buffer_free(g->emergency_buffer, ep)) return;
+ free(ep);
+}
+
+
+#endif /* arm_exceptions_free_c */
+#ifdef arm_exceptions_throw_c
+
+/* This routine is called when a foreign runtime catches one of our exception
+ * objects and then exits its catch by a means other than rethrow.
+ * We should clean it up as if we had caught it ourselves.
+ */
+
+static void external_exception_termination(_Unwind_Reason_Code c, UCB *ucbp)
+{
+ NAMES::eh_catch_semantics(ucbp);
+ __cxa_end_catch();
+}
+
+
+/* Initiate a throw */
+
+#pragma push
+#pragma exceptions_unwind
+
+void __cxa_throw(void *eop, const type_info *t, cppdtorptr d)
+{
+ __cxa_exception *ep = (__cxa_exception *)((char *)eop - sizeof(__cxa_exception));
+ UCB *ucbp = &ep->ucb;
+
+ // Initialise the remaining LEO and UCB fields not done by __cxa_allocate_exception
+
+ ucbp->exception_cleanup = external_exception_termination;
+ ep->exceptionType = t;
+ ep->exceptionDestructor = d;
+ ep->propagationCount = 1; // Propagating by 1 throw
+
+ // Increment the uncaught C++ exceptions count
+
+ __cxa_eh_globals *g = __cxa_get_globals();
+ g->uncaughtExceptions++;
+
+ // Tell debugger what's happening
+
+ DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_CPP, _UAACT_STARTING, t);
+
+ // Initiate unwinding - if we get control back, call C++ routine terminate()
+
+ _Unwind_RaiseException(ucbp);
+
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_throw: throw failed\n");
+#endif
+
+ __cxa_call_terminate(ucbp);
+}
+
+#pragma pop
+
+/* ----- Type matching: ----- */
+
+/* This is located here so that (in ARM's implementation) it is only retained in
+ * an image if the application itself throws.
+ */
+
+/* Type matching functions.
+ * C++ DR126 says the matching rules for fnspecs are intended to be the same as
+ * those for catch:
+ * "A function is said to allow an exception of type E if its exception-specification
+ * contains a type T for which a handler of type T would be a match (15.3 except.handle)
+ * for an exception of type E."
+ * Thus we have a single type matching rule.
+ */
+
+/* Helper macros: */
+
+#define CV_quals_of_pointee(P) (((const abi::__pbase_type_info *)(P))->__flags & \
+ (abi::__pbase_type_info::__const_mask | \
+ abi::__pbase_type_info::__volatile_mask))
+
+#define is_const(QUALS) (((QUALS) & abi::__pbase_type_info::__const_mask) != 0)
+
+#define any_qualifier_missing(TEST_QUALS, REF_QUALS) ((~(TEST_QUALS) & (REF_QUALS)) != 0)
+
+/* A routine is required for derived class to base class conversion.
+ * This is obtained via a macro definition DERIVED_TO_BASE_CONVERSION
+ * in unwind_env.h.
+ */
+
+/* External entry point:
+ * Type check the c++ rtti object for compatibility against the type of
+ * the object containing the ucb. Return a pointer to the matched object
+ * (possibly a non-leftmost baseclass of the exception object)
+ */
+bool __cxa_type_match(UCB *ucbp, const type_info *match_type, void **matched_objectpp)
+{
+ if (NAMES::is_foreign_exception(ucbp))
+ return false;
+
+ __cxa_exception *ep = ucbp_to_ep(ucbp);
+ const type_info *throw_type = ep->exceptionType;
+ bool previous_qualifiers_include_const = true; // for pointer qualification conversion
+ unsigned int pointer_depth = 0;
+ void *original_objectp = ep + 1;
+ void *current_objectp = original_objectp;
+
+ for (;;) {
+
+ // Match if identical
+
+ if (throw_type == match_type) {
+ *matched_objectpp = original_objectp;
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: success (exact match after any ptrs)\n");
+#endif
+ return true;
+ }
+
+ // Fail if one is a pointer and the other isn't
+
+ const type_info *type_throw_type = &typeid(*throw_type);
+ const type_info *type_match_type = &typeid(*match_type);
+
+ if ((type_throw_type == &typeid(abi::__pointer_type_info) ||
+ type_match_type == &typeid(abi::__pointer_type_info)) &&
+ type_throw_type != type_match_type) {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: failed (mixed ptr/non-ptr)\n");
+#endif
+ return false;
+ }
+
+ // Both are pointers or neither is
+ if (type_throw_type == &typeid(abi::__pointer_type_info)) {
+ // Both are pointers
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: throwing a ptr\n");
+#endif
+ pointer_depth++;
+ // Check match_type is at least as CV-qualified as throw_type
+ unsigned int match_quals = CV_quals_of_pointee(match_type);
+ unsigned int throw_quals = CV_quals_of_pointee(throw_type);
+ if (any_qualifier_missing(match_quals, throw_quals)) {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: failed (missing qualifiers)\n");
+#endif
+ return false;
+ }
+ // If the match type has additional qualifiers not found in the
+ // throw type, any previous qualifiers must have included const
+ if (any_qualifier_missing(throw_quals, match_quals) &&
+ !previous_qualifiers_include_const) {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: failed (not all qualifiers have const)\n");
+#endif
+ return false;
+ }
+ if (!is_const(match_quals))
+ previous_qualifiers_include_const = false;
+ throw_type = ((const abi::__pbase_type_info *)throw_type)->__pointee;
+ match_type = ((const abi::__pbase_type_info *)match_type)->__pointee;
+ if (current_objectp != NULL)
+ current_objectp = *(void **)current_objectp;
+ continue;
+ }
+
+ // Neither is a pointer now but qualification conversion has been done.
+ // See if pointer conversion on the original was possible.
+ // T* will match void*
+
+ if (pointer_depth == 1 && match_type == &typeid(void)) {
+ *matched_objectpp = original_objectp;
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: success(conversion to void *)\n");
+#endif
+ return true;
+ }
+
+ // Else if we have 2 class types, a derived class is matched by a
+ // non-ambiguous public base class (perhaps not a leftmost one).
+ // __si_class_type_info and __vmi_class_type_info are classes with bases.
+
+ void *matched_base_p;
+
+ if (pointer_depth < 2 &&
+ (type_throw_type == &typeid(abi::__si_class_type_info) ||
+ type_throw_type == &typeid(abi::__vmi_class_type_info))) {
+ if (DERIVED_TO_BASE_CONVERSION(current_objectp, &matched_base_p,
+ throw_type, match_type)) {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: success (matched base 0x%x of 0x%x%s, thrown object 0x%x)\n",
+ matched_base_p, current_objectp,
+ pointer_depth == 0 ? "" : " via ptr",
+ original_objectp);
+#endif
+ *matched_objectpp = pointer_depth == 0 ? matched_base_p : original_objectp;
+ return true;
+ } else {
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: failed (derived to base failed)\n");
+#endif
+ return false;
+ }
+ }
+
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_type_match: failed (types simply differ)\n");
+#endif
+ return false;
+ } /* for */
+}
+
+
+/* For debugging purposes: */
+#ifdef DEBUG
+extern "C" bool debug__cxa_type_match(void *objptr,
+ const type_info *throw_type,
+ const type_info *catch_type,
+ void **matched_objectpp)
+{
+ /* Create enough of an exception object that the type-matcher can run, then
+ * check the type. Objptr is expected to be the result of a call to
+ * __cxa_allocate_exception, which has then been copy-constructed.
+ */
+ __cxa_exception *e = ((__cxa_exception *)objptr) - 1;
+ e->exceptionType = throw_type;
+ return __cxa_type_match(&e->ucb, catch_type, matched_objectpp);
+}
+#endif
+
+
+#endif /* arm_exceptions_throw_c */
+#ifdef arm_exceptions_rethrow_c
+
+/* Redeclare _Unwind_RaiseException as weak (if WEAKDECL is defined
+ * appropriately) so the use from __cxa_rethrow does not on its own
+ * force the unwind library to be loaded.
+ */
+
+extern "C" WEAKDECL _Unwind_Reason_Code _Unwind_RaiseException(UCB *ucbp);
+
+#pragma exceptions_unwind
+
+void __cxa_rethrow(void)
+{
+ // Recover the exception object - it is the most recent caught exception object
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep = g->caughtExceptions;
+ bool foreign;
+
+ // Must call terminate here if no such exception
+ if (ep == NULL) NAMES::call_terminate_handler(NULL);
+
+ UCB *ucbp = &ep->ucb;
+
+ // Mark the object as being propagated by throw, preventing multiple
+ // propagation and also permitting __cxa_end_catch to do the right
+ // thing when it is called from the handler's cleanup.
+
+ ep->propagationCount++;
+
+ // Now reraise, taking care with foreign exceptions
+
+ foreign = NAMES::is_foreign_exception(ucbp);
+ if (foreign) {
+ // Indirect through the intermediate object to the foreign ucb
+ ucbp = (UCB *)ep->exceptionType;
+ } else {
+ // Increment the uncaught C++ exceptions count
+ g->uncaughtExceptions++;
+ }
+
+ // Tell debugger what's happening
+
+ DEBUGGER_BOTTLENECK(ucbp, _UASUBSYS_CPP, _UAACT_STARTING, foreign ? NULL : ep->exceptionType);
+
+ // Initiate unwinding - if we get control back, call C++ routine terminate()
+
+ _Unwind_RaiseException(ucbp);
+
+#ifdef PRINTED_DIAGNOSTICS
+ printf("__cxa_rethrow: throw failed\n");
+#endif
+
+ __cxa_call_terminate(ucbp);
+}
+
+#endif /* arm_exceptions_rethrow_c */
+#ifdef arm_exceptions_foreign_c
+
+/* During catch and cleanup, foreign exception objects are dealt with using
+ * an intermediate __cxa_exception block in the appropriate exceptions
+ * chain. This block has the same exception_class as the real foreign
+ * ucb, and points to the real ucb via the intermediate block's exceptionType
+ * field. This helper function checks whether it has been passed such an
+ * intermediate block and sets one up if not. Only call it when the UCB
+ * is known to belong to a foreign exception.
+ */
+
+__cxa_exception *NAMES::get_foreign_intermediary(__cxa_exception *head_ep, UCB *ucbp)
+{
+ if (head_ep != NULL) {
+ UCB *head_ucbp = &head_ep->ucb;
+ if (NAMES::same_exceptions_class(&head_ucbp->exception_class, &ucbp->exception_class) &&
+ (UCB *)head_ep->exceptionType == ucbp)
+ return head_ep;
+ }
+
+ // Create an intermediate block. Only initialise as much as necessary
+ __cxa_exception *ep = ((__cxa_exception *)__cxa_allocate_exception(0)) - 1;
+ UCB *new_ucbp = &ep->ucb;
+ memcpy(new_ucbp->exception_class, ucbp->exception_class, EXCEPTIONS_CLASS_SIZE);
+ ep->propagationCount = 0; // Not propagating
+ ep->handlerCount = 0; // Not handled
+ ep->nextCaughtException = NULL; // Not in chain
+ ep->exceptionType = (const type_info *)ucbp; // The foreign UCB
+ return ep;
+}
+
+
+#endif /* arm_exceptions_foreign_c */
+#ifdef arm_exceptions_cleanup_c
+
+bool __cxa_begin_cleanup(UCB *ucbp)
+{
+ // Indicate that a cleanup is about to start.
+ // Save the exception pointer over the cleanup for recovery later, using a chain.
+ // If we allowed the exception to be rethrown in a cleanup, then
+ // the object might appear multiple times at the head of this chain,
+ // and the propagationCount could be used to track this - at this point,
+ // the object is logically in the chain propagationCount-1 times, and
+ // physically 0 or 1 times. Thus if propagationCount == 1 we should insert
+ // it physically. A similar rule is used for physical removal in
+ //__cxa_end_cleanup.
+ // Foreign exceptions are handled via an intermediate __cxa_exception object
+ // in a similar way as __cxa_begin_catch.
+
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep;
+
+ if (NAMES::is_foreign_exception(ucbp)) {
+ ep = NAMES::get_foreign_intermediary(g->propagatingExceptions, ucbp);
+ ep->propagationCount++; // Indicate one (or one additional) propagation
+ } else {
+ ep = ucbp_to_ep(ucbp);
+ }
+
+ if (ep->propagationCount == 1) {
+ // Insert into chain
+ ep->nextPropagatingException = g->propagatingExceptions;
+ g->propagatingExceptions = ep;
+ }
+
+ return true;
+}
+
+
+// Helper function for __cxa_end_cleanup
+
+extern "C" UCB * __ARM_cxa_end_cleanup(void)
+{
+ // Recover and return the currently propagating exception (from the
+ // head of the propagatingExceptions chain).
+ // propagationCount at this moment is a logical count of how many times the
+ // item is in the chain so physically unchain it when this count is 1.
+ // Foreign exceptions use an intermediary.
+
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep = g->propagatingExceptions;
+
+ if (ep == NULL) terminate();
+
+ UCB *ucbp = &ep->ucb;
+ if (NAMES::is_foreign_exception(ucbp)) {
+ // Get the foreign ucb
+ ucbp = (UCB *)ep->exceptionType;
+ if (ep->propagationCount == 1) {
+ // Free the intermediate ucb (see description in __cxa_begin_catch)
+ void *eop = (void *)(ep + 1);
+ g->propagatingExceptions = ep->nextPropagatingException;
+ __cxa_free_exception(eop);
+ } else {
+ ep->propagationCount--;
+ }
+ } else {
+ // Not foreign
+ if (ep->propagationCount == 1) { // logically in chain once - so unchain
+ g->propagatingExceptions = ep->nextPropagatingException;
+ }
+ }
+ return ucbp;
+}
+
+// __cxa_end_cleanup is called at the end of a cleanup fragment.
+// It must do the C++ housekeeping, then call _Unwind_Resume, but it must
+// damage no significant registers in the process.
+
+__asm void __cxa_end_cleanup(void) {
+ extern __ARM_cxa_end_cleanup;
+ extern _Unwind_Resume WEAKASMDECL;
+
+#ifdef __thumb
+ preserve8; // This is preserve8 (ARM assembler heuristics are inadequate)
+ push {r1-r7};
+ mov r2, r8;
+ mov r3, r9;
+ mov r4, r10;
+ mov r5, r11;
+ push {r1-r5};
+ bl __ARM_cxa_end_cleanup; // returns UCB address in r0
+ pop {r1-r5};
+ mov r8, r2;
+ mov r9, r3;
+ mov r10, r4;
+ mov r11, r5;
+ pop {r1-r7};
+ bl _Unwind_Resume; // won't return
+#else
+ stmfd r13!, {r1-r12}
+ bl __ARM_cxa_end_cleanup; // returns UCB address in r0
+ ldmia r13!, {r1-r12};
+ b _Unwind_Resume; // won't return
+#endif
+}
+
+
+#endif /* arm_exceptions_cleanup_c */
+#ifdef arm_exceptions_catchsemantics_c
+
+/* Update date structures as if catching an object.
+ * Call this from __cxa_begin_catch when actually catching an object,
+ * and from external_exception_termination when called by a foreign runtime
+ * after one of our objects was caught.
+ */
+
+void NAMES::eh_catch_semantics(UCB *ucbp)
+{
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep;
+
+ if (NAMES::is_foreign_exception(ucbp)) {
+ // Foreign exception. Get the associated intermediary block or
+ // make one if there isn't one already.
+ // In the case of a rethrow, the foreign object may already be on
+ // the handled exceptions chain (it will be first).
+ ep = NAMES::get_foreign_intermediary(g->caughtExceptions, ucbp);
+ } else {
+ // Not foreign
+ ep = ucbp_to_ep(ucbp);
+ // Decrement the propagation count
+ ep->propagationCount--;
+ // Decrement the total uncaught C++ exceptions count
+ g->uncaughtExceptions--;
+ }
+
+ // Common code for our EO's, and foreign ones where we work on the intermediate EO
+
+ // Increment the handler count for this exception object
+ ep->handlerCount++;
+
+ // Push the ep onto the "handled exceptions" chain if it is not already there.
+ // (If catching a rethrow, it may already be there)
+
+ if (ep->nextCaughtException == NULL) {
+ ep->nextCaughtException = g->caughtExceptions;
+ g->caughtExceptions = ep;
+ }
+}
+
+
+#endif /* arm_exceptions_catchsemantics_c */
+#ifdef arm_exceptions_begincatch_c
+
+void *__cxa_begin_catch(UCB *ucbp)
+{
+ void *match = (void *)ucbp->barrier_cache.bitpattern[0]; // The matched object, if any
+
+ // Update the data structures
+
+ NAMES::eh_catch_semantics(ucbp);
+
+ // Tell the unwinder the exception propagation has finished,
+ // and return the object pointer
+
+ _Unwind_Complete(ucbp);
+ return match;
+}
+
+
+#endif /* arm_exceptions_begincatch_c */
+#ifdef arm_exceptions_endcatch_c
+
+#pragma exceptions_unwind
+
+void __cxa_end_catch(void)
+{
+ // Recover the exception object - it is the most recent caught exception object
+ __cxa_eh_globals *g = __cxa_get_globals();
+ __cxa_exception *ep = g->caughtExceptions;
+
+ if (ep == NULL) terminate();
+
+ // Rethrow in progress?
+
+ bool object_being_rethrown = ep->propagationCount != 0;
+
+ // Decrement the handler count for this exception object
+ ep->handlerCount--;
+
+ // Unstack the object if it is no longer being handled anywhere.
+ // Destroy and free the object if it is no longer alive -
+ // it is dead if its handler count becomes 0, unless it is
+ // about to be rethrown.
+ // If the dtor throws, allow its exception to propagate.
+ // Do different things if it is a foreign exception object.
+
+ if (ep->handlerCount == 0) {
+ void *eop = (void *)(ep + 1);
+ UCB *ucbp = &ep->ucb;
+ bool foreign = NAMES::is_foreign_exception(ucbp);
+
+ // Unstack it from the caught exceptions stack - it is guaranteed to be top item.
+ g->caughtExceptions = ep->nextCaughtException;
+
+ if (foreign) {
+ // Get the foreign ucb and free the intermediate ucb (see description in __cxa_begin_catch)
+ ucbp = (UCB *)ep->exceptionType;
+ __cxa_free_exception(eop);
+ } else {
+ ep->nextCaughtException = NULL; // So __cxa_begin_catch knows it isn't in the chain
+ }
+
+ // Now destroy the exception object if it's no longer needed
+ if (!object_being_rethrown) {
+ if (foreign) {
+
+ // Notify the foreign language, if it so requested
+ if (ucbp->exception_cleanup != NULL)
+ (ucbp->exception_cleanup)(_URC_FOREIGN_EXCEPTION_CAUGHT, ucbp);
+
+ } else {
+
+ // One of our objects: do C++-specific semantics
+
+ if (ep->exceptionDestructor != NULL) {
+ // Run the dtor. If it throws, free the memory anyway and
+ // propagate the new exception.
+#ifdef ARM_EXCEPTIONS_ENABLED
+ try {
+ (ep->exceptionDestructor)(eop);
+ } catch(...) {
+ // Free the memory and reraise
+ __cxa_free_exception(eop);
+ throw;
+ }
+#else
+ (ep->exceptionDestructor)(eop);
+#endif
+ }
+ // Dtor (if there was one) didn't throw. Free the memory.
+ __cxa_free_exception(eop);
+ } // !foreign
+ } // !object_being_rethrown
+ } // ep->handlerCount == 0
+}
+
+
+#endif /* arm_exceptions_endcatch_c */
+#ifdef arm_exceptions_bad_typeid_c
+
+#pragma exceptions_unwind
+
+void __cxa_bad_typeid(void)
+{
+ throw std::bad_typeid();
+}
+
+
+#endif /* arm_exceptions_bad_typeid_c */
+#ifdef arm_exceptions_bad_cast_c
+
+#pragma exceptions_unwind
+
+void __cxa_bad_cast(void)
+{
+ throw std::bad_cast();
+}
+
+
+#endif /* arm_exceptions_bad_cast_c */