Date: Fri, 25 Nov 2011 15:48:31 +0000 (UTC) From: David Chisnall <theraven@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-vendor@freebsd.org Subject: svn commit: r227973 - vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4 Message-ID: <201111251548.pAPFmVqs049490@svn.freebsd.org>
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Author: theraven Date: Fri Nov 25 15:48:30 2011 New Revision: 227973 URL: http://svn.freebsd.org/changeset/base/227973 Log: libcxxrt version snapshot created. Approved by: dim (mentor) Added: vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/ - copied from r227971, vendor/libcxxrt/dist/ vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/unwind-arm.h - copied unchanged from r227972, vendor/libcxxrt/dist/unwind-arm.h vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/unwind-itanium.h - copied unchanged from r227972, vendor/libcxxrt/dist/unwind-itanium.h vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/unwind.h - copied unchanged from r227972, vendor/libcxxrt/dist/unwind.h Replaced: vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/cxxabi.h - copied unchanged from r227972, vendor/libcxxrt/dist/cxxabi.h vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/dwarf_eh.h - copied unchanged from r227972, vendor/libcxxrt/dist/dwarf_eh.h vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/exception.cc - copied unchanged from r227972, vendor/libcxxrt/dist/exception.cc vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/guard.cc - copied unchanged from r227972, vendor/libcxxrt/dist/guard.cc Copied: vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/cxxabi.h (from r227972, vendor/libcxxrt/dist/cxxabi.h) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/cxxabi.h Fri Nov 25 15:48:30 2011 (r227973, copy of r227972, vendor/libcxxrt/dist/cxxabi.h) @@ -0,0 +1,219 @@ +#ifndef __CXXABI_H_ +#define __CXXABI_H_ +#include <stdint.h> +#include "unwind.h" +namespace std +{ + class type_info; +} +/* + * The cxxabi.h header provides a set of public definitions for types and + * functions defined by the Itanium C++ ABI specification. For reference, see + * the ABI specification here: + * + * http://sourcery.mentor.com/public/cxx-abi/abi.html + * + * All deviations from this specification, unless otherwise noted, are + * accidental. + */ + +#ifdef __cplusplus +namespace __cxxabiv1 { +extern "C" { +#endif +/** + * Function type to call when an unexpected exception is encountered. + */ +typedef void (*unexpected_handler)(); +/** + * Function type to call when an unrecoverable condition is encountered. + */ +typedef void (*terminate_handler)(); + + +/** + * Structure used as a header on thrown exceptions. This is the same layout as + * defined by the Itanium ABI spec, so should be interoperable with any other + * implementation of this spec, such as GNU libsupc++. + * + * This structure is allocated when an exception is thrown. Unwinding happens + * in two phases, the first looks for a handler and the second installs the + * context. This structure stores a cache of the handler location between + * phase 1 and phase 2. Unfortunately, cleanup information is not cached, so + * must be looked up in both phases. This happens for two reasons. The first + * is that we don't know how many frames containing cleanups there will be, and + * we should avoid dynamic allocation during unwinding (the exception may be + * reporting that we've run out of memory). The second is that finding + * cleanups is much cheaper than finding handlers, because we don't have to + * look at the type table at all. + * + * Note: Several fields of this structure have not-very-informative names. + * These are taken from the ABI spec and have not been changed to make it + * easier for people referring to to the spec while reading this code. + */ +struct __cxa_exception +{ +#if __LP64__ + /** + * Reference count. Used to support the C++11 exception_ptr class. This + * is prepended to the structure in 64-bit mode and squeezed in to the + * padding left before the 64-bit aligned _Unwind_Exception at the end in + * 32-bit mode. + * + * Note that it is safe to extend this structure at the beginning, rather + * than the end, because the public API for creating it returns the address + * of the end (where the exception object can be stored). + */ + uintptr_t referenceCount; +#endif + /** Type info for the thrown object. */ + std::type_info *exceptionType; + /** Destructor for the object, if one exists. */ + void (*exceptionDestructor) (void *); + /** Handler called when an exception specification is violated. */ + unexpected_handler unexpectedHandler; + /** Hander called to terminate. */ + terminate_handler terminateHandler; + /** + * Next exception in the list. If an exception is thrown inside a catch + * block and caught in a nested catch, this points to the exception that + * will be handled after the inner catch block completes. + */ + __cxa_exception *nextException; + /** + * The number of handlers that currently have references to this + * exception. The top (non-sign) bit of this is used as a flag to indicate + * that the exception is being rethrown, so should not be deleted when its + * handler count reaches 0 (which it doesn't with the top bit set). + */ + int handlerCount; +#ifdef __arm__ + /** + * The ARM EH ABI requires the unwind library to keep track of exceptions + * during cleanups. These support nesting, so we need to keep a list of + * them. + */ + _Unwind_Exception *nextCleanup; + /** + * The number of cleanups that are currently being run on this exception. + */ + int cleanupCount; +#endif + /** + * The selector value to be returned when installing the catch handler. + * Used at the call site to determine which catch() block should execute. + * This is found in phase 1 of unwinding then installed in phase 2. + */ + int handlerSwitchValue; + /** + * The action record for the catch. This is cached during phase 1 + * unwinding. + */ + const char *actionRecord; + /** + * Pointer to the language-specific data area (LSDA) for the handler + * frame. This is unused in this implementation, but set for ABI + * compatibility in case we want to mix code in very weird ways. + */ + const char *languageSpecificData; + /** The cached landing pad for the catch handler.*/ + void *catchTemp; + /** + * The pointer that will be returned as the pointer to the object. When + * throwing a class and catching a virtual superclass (for example), we + * need to adjust the thrown pointer to make it all work correctly. + */ + void *adjustedPtr; +#if !__LP64__ + /** + * Reference count. Used to support the C++11 exception_ptr class. This + * is prepended to the structure in 64-bit mode and squeezed in to the + * padding left before the 64-bit aligned _Unwind_Exception at the end in + * 32-bit mode. + * + * Note that it is safe to extend this structure at the beginning, rather + * than the end, because the public API for creating it returns the address + * of the end (where the exception object can be stored) + */ + uintptr_t referenceCount; +#endif + /** The language-agnostic part of the exception header. */ + _Unwind_Exception unwindHeader; +}; + +/** + * ABI-specified globals structure. Returned by the __cxa_get_globals() + * function and its fast variant. This is a per-thread structure - every + * thread will have one lazily allocated. + * + * This structure is defined by the ABI, so may be used outside of this + * library. + */ +struct __cxa_eh_globals +{ + /** + * A linked list of exceptions that are currently caught. There may be + * several of these in nested catch() blocks. + */ + __cxa_exception *caughtExceptions; + /** + * The number of uncaught exceptions. + */ + unsigned int uncaughtExceptions; +}; +/** + * ABI function returning the __cxa_eh_globals structure. + */ +__cxa_eh_globals *__cxa_get_globals(void); +/** + * Version of __cxa_get_globals() assuming that __cxa_get_globals() has already + * been called at least once by this thread. + */ +__cxa_eh_globals *__cxa_get_globals_fast(void); + +/** + * Throws an exception returned by __cxa_current_primary_exception(). This + * exception may have been caught in another thread. + */ +void __cxa_rethrow_primary_exception(void* thrown_exception); +/** + * Returns the current exception in a form that can be stored in an + * exception_ptr object and then rethrown by a call to + * __cxa_rethrow_primary_exception(). + */ +void *__cxa_current_primary_exception(void); +/** + * Increments the reference count of an exception. Called when an + * exception_ptr is copied. + */ +void __cxa_increment_exception_refcount(void* thrown_exception); +/** + * Decrements the reference count of an exception. Called when an + * exception_ptr is deleted. + */ +void __cxa_decrement_exception_refcount(void* thrown_exception); +/** + * Demangles a C++ symbol or type name. The buffer, if non-NULL, must be + * allocated with malloc() and must be *n bytes or more long. This function + * may call realloc() on the value pointed to by buf, and will return the + * length of the string via *n. + * + * The value pointed to by status is set to one of the following: + * + * 0: success + * -1: memory allocation failure + * -2: invalid mangled name + * -3: invalid arguments + */ +char* __cxa_demangle(const char* mangled_name, + char* buf, + size_t* n, + int* status); +#ifdef __cplusplus +} // extern "C" +} // namespace + +namespace abi = __cxxabiv1; + +#endif /* __cplusplus */ +#endif /* __CXXABI_H_ */ Copied: vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/dwarf_eh.h (from r227972, vendor/libcxxrt/dist/dwarf_eh.h) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/dwarf_eh.h Fri Nov 25 15:48:30 2011 (r227973, copy of r227972, vendor/libcxxrt/dist/dwarf_eh.h) @@ -0,0 +1,454 @@ +/** + * dwarf_eh.h - Defines some helper functions for parsing DWARF exception + * handling tables. + * + * This file contains various helper functions that are independent of the + * language-specific code. It can be used in any personality function for the + * Itanium ABI. + */ +#include <assert.h> + +// TODO: Factor out Itanium / ARM differences. We probably want an itanium.h +// and arm.h that can be included by this file depending on the target ABI. + +// _GNU_SOURCE must be defined for unwind.h to expose some of the functions +// that we want. If it isn't, then we define it and undefine it to make sure +// that it doesn't impact the rest of the program. +#ifndef _GNU_SOURCE +# define _GNU_SOURCE 1 +# include "unwind.h" +# undef _GNU_SOURCE +#else +# include "unwind.h" +#endif + +#include <stdint.h> + +/// Type used for pointers into DWARF data +typedef unsigned char *dw_eh_ptr_t; + +// Flag indicating a signed quantity +#define DW_EH_PE_signed 0x08 +/// DWARF data encoding types. +enum dwarf_data_encoding +{ + /// Unsigned, little-endian, base 128-encoded (variable length). + DW_EH_PE_uleb128 = 0x01, + /// Unsigned 16-bit integer. + DW_EH_PE_udata2 = 0x02, + /// Unsigned 32-bit integer. + DW_EH_PE_udata4 = 0x03, + /// Unsigned 64-bit integer. + DW_EH_PE_udata8 = 0x04, + /// Signed, little-endian, base 128-encoded (variable length) + DW_EH_PE_sleb128 = DW_EH_PE_uleb128 | DW_EH_PE_signed, + /// Signed 16-bit integer. + DW_EH_PE_sdata2 = DW_EH_PE_udata2 | DW_EH_PE_signed, + /// Signed 32-bit integer. + DW_EH_PE_sdata4 = DW_EH_PE_udata4 | DW_EH_PE_signed, + /// Signed 32-bit integer. + DW_EH_PE_sdata8 = DW_EH_PE_udata8 | DW_EH_PE_signed +}; + +/** + * Returns the encoding for a DWARF EH table entry. The encoding is stored in + * the low four of an octet. The high four bits store the addressing mode. + */ +static inline enum dwarf_data_encoding get_encoding(unsigned char x) +{ + return (enum dwarf_data_encoding)(x & 0xf); +} + +/** + * DWARF addressing mode constants. When reading a pointer value from a DWARF + * exception table, you must know how it is stored and what the addressing mode + * is. The low four bits tell you the encoding, allowing you to decode a + * number. The high four bits tell you the addressing mode, allowing you to + * turn that number into an address in memory. + */ +enum dwarf_data_relative +{ + /// Value is omitted + DW_EH_PE_omit = 0xff, + /// Absolute pointer value + DW_EH_PE_absptr = 0x00, + /// Value relative to program counter + DW_EH_PE_pcrel = 0x10, + /// Value relative to the text segment + DW_EH_PE_textrel = 0x20, + /// Value relative to the data segment + DW_EH_PE_datarel = 0x30, + /// Value relative to the start of the function + DW_EH_PE_funcrel = 0x40, + /// Aligned pointer (Not supported yet - are they actually used?) + DW_EH_PE_aligned = 0x50, + /// Pointer points to address of real value + DW_EH_PE_indirect = 0x80 +}; +/** + * Returns the addressing mode component of this encoding. + */ +static inline enum dwarf_data_relative get_base(unsigned char x) +{ + return (enum dwarf_data_relative)(x & 0x70); +} +/** + * Returns whether an encoding represents an indirect address. + */ +static int is_indirect(unsigned char x) +{ + return ((x & DW_EH_PE_indirect) == DW_EH_PE_indirect); +} + +/** + * Returns the size of a fixed-size encoding. This function will abort if + * called with a value that is not a fixed-size encoding. + */ +static inline int dwarf_size_of_fixed_size_field(unsigned char type) +{ + switch (get_encoding(type)) + { + default: abort(); + case DW_EH_PE_sdata2: + case DW_EH_PE_udata2: return 2; + case DW_EH_PE_sdata4: + case DW_EH_PE_udata4: return 4; + case DW_EH_PE_sdata8: + case DW_EH_PE_udata8: return 8; + case DW_EH_PE_absptr: return sizeof(void*); + } +} + +/** + * Read an unsigned, little-endian, base-128, DWARF value. Updates *data to + * point to the end of the value. Stores the number of bits read in the value + * pointed to by b, allowing you to determine the value of the highest bit, and + * therefore the sign of a signed value. + * + * This function is not intended to be called directly. Use read_sleb128() or + * read_uleb128() for reading signed and unsigned versions, respectively. + */ +static uint64_t read_leb128(dw_eh_ptr_t *data, int *b) +{ + uint64_t uleb = 0; + unsigned int bit = 0; + unsigned char digit = 0; + // We have to read at least one octet, and keep reading until we get to one + // with the high bit unset + do + { + // This check is a bit too strict - we should also check the highest + // bit of the digit. + assert(bit < sizeof(uint64_t) * 8); + // Get the base 128 digit + digit = (**data) & 0x7f; + // Add it to the current value + uleb += digit << bit; + // Increase the shift value + bit += 7; + // Proceed to the next octet + (*data)++; + // Terminate when we reach a value that does not have the high bit set + // (i.e. which was not modified when we mask it with 0x7f) + } while ((*(*data - 1)) != digit); + *b = bit; + + return uleb; +} + +/** + * Reads an unsigned little-endian base-128 value starting at the address + * pointed to by *data. Updates *data to point to the next byte after the end + * of the variable-length value. + */ +static int64_t read_uleb128(dw_eh_ptr_t *data) +{ + int b; + return read_leb128(data, &b); +} + +/** + * Reads a signed little-endian base-128 value starting at the address pointed + * to by *data. Updates *data to point to the next byte after the end of the + * variable-length value. + */ +static int64_t read_sleb128(dw_eh_ptr_t *data) +{ + int bits; + // Read as if it's signed + uint64_t uleb = read_leb128(data, &bits); + // If the most significant bit read is 1, then we need to sign extend it + if ((uleb >> (bits-1)) == 1) + { + // Sign extend by setting all bits in front of it to 1 + uleb |= ((int64_t)-1) << bits; + } + return (int64_t)uleb; +} +/** + * Reads a value using the specified encoding from the address pointed to by + * *data. Updates the value of *data to point to the next byte after the end + * of the data. + */ +static uint64_t read_value(char encoding, dw_eh_ptr_t *data) +{ + enum dwarf_data_encoding type = get_encoding(encoding); + uint64_t v; + switch (type) + { + // Read fixed-length types +#define READ(dwarf, type) \ + case dwarf:\ + v = (uint64_t)(*(type*)(*data));\ + *data += sizeof(type);\ + break; + READ(DW_EH_PE_udata2, uint16_t) + READ(DW_EH_PE_udata4, uint32_t) + READ(DW_EH_PE_udata8, uint64_t) + READ(DW_EH_PE_sdata2, int16_t) + READ(DW_EH_PE_sdata4, int32_t) + READ(DW_EH_PE_sdata8, int64_t) + READ(DW_EH_PE_absptr, intptr_t) +#undef READ + // Read variable-length types + case DW_EH_PE_sleb128: + v = read_sleb128(data); + break; + case DW_EH_PE_uleb128: + v = read_uleb128(data); + break; + default: abort(); + } + + return v; +} + +/** + * Resolves an indirect value. This expects an unwind context, an encoding, a + * decoded value, and the start of the region as arguments. The returned value + * is a pointer to the address identified by the encoded value. + * + * If the encoding does not specify an indirect value, then this returns v. + */ +static uint64_t resolve_indirect_value(_Unwind_Context *c, + unsigned char encoding, + int64_t v, + dw_eh_ptr_t start) +{ + switch (get_base(encoding)) + { + case DW_EH_PE_pcrel: + v += (uint64_t)start; + break; + case DW_EH_PE_textrel: + v += (uint64_t)_Unwind_GetTextRelBase(c); + break; + case DW_EH_PE_datarel: + v += (uint64_t)_Unwind_GetDataRelBase(c); + break; + case DW_EH_PE_funcrel: + v += (uint64_t)_Unwind_GetRegionStart(c); + default: + break; + } + // If this is an indirect value, then it is really the address of the real + // value + // TODO: Check whether this should really always be a pointer - it seems to + // be a GCC extensions, so not properly documented... + if (is_indirect(encoding)) + { + v = (uint64_t)(uintptr_t)*(void**)v; + } + return v; +} + + +/** + * Reads an encoding and a value, updating *data to point to the next byte. + */ +static inline void read_value_with_encoding(_Unwind_Context *context, + dw_eh_ptr_t *data, + uint64_t *out) +{ + dw_eh_ptr_t start = *data; + unsigned char encoding = *((*data)++); + // If this value is omitted, skip it and don't touch the output value + if (encoding == DW_EH_PE_omit) { return; } + + *out = read_value(encoding, data); + *out = resolve_indirect_value(context, encoding, *out, start); +} + +/** + * Structure storing a decoded language-specific data area. Use parse_lsda() + * to generate an instance of this structure from the address returned by the + * generic unwind library. + * + * You should not need to inspect the fields of this structure directly if you + * are just using this header. The structure stores the locations of the + * various tables used for unwinding exceptions and is used by the functions + * for reading values from these tables. + */ +struct dwarf_eh_lsda +{ + /// The start of the region. This is a cache of the value returned by + /// _Unwind_GetRegionStart(). + dw_eh_ptr_t region_start; + /// The start of the landing pads table. + dw_eh_ptr_t landing_pads; + /// The start of the type table. + dw_eh_ptr_t type_table; + /// The encoding used for entries in the type tables. + unsigned char type_table_encoding; + /// The location of the call-site table. + dw_eh_ptr_t call_site_table; + /// The location of the action table. + dw_eh_ptr_t action_table; + /// The encoding used for entries in the call-site table. + unsigned char callsite_encoding; +}; + +/** + * Parse the header on the language-specific data area and return a structure + * containing the addresses and encodings of the various tables. + */ +static inline struct dwarf_eh_lsda parse_lsda(_Unwind_Context *context, + unsigned char *data) +{ + struct dwarf_eh_lsda lsda; + + lsda.region_start = (dw_eh_ptr_t)(uintptr_t)_Unwind_GetRegionStart(context); + + // If the landing pads are relative to anything other than the start of + // this region, find out where. This is @LPStart in the spec, although the + // encoding that GCC uses does not quite match the spec. + uint64_t v = (uint64_t)(uintptr_t)lsda.region_start; + read_value_with_encoding(context, &data, &v); + lsda.landing_pads = (dw_eh_ptr_t)(uintptr_t)v; + + // If there is a type table, find out where it is. This is @TTBase in the + // spec. Note: we find whether there is a type table pointer by checking + // whether the leading byte is DW_EH_PE_omit (0xff), which is not what the + // spec says, but does seem to be how G++ indicates this. + lsda.type_table = 0; + lsda.type_table_encoding = *data++; + if (lsda.type_table_encoding != DW_EH_PE_omit) + { + v = read_uleb128(&data); + dw_eh_ptr_t type_table = data; + type_table += v; + lsda.type_table = type_table; + //lsda.type_table = (uintptr_t*)(data + v); + } +#if __arm__ + lsda.type_table_encoding = (DW_EH_PE_pcrel | DW_EH_PE_indirect); +#endif + + lsda.callsite_encoding = (enum dwarf_data_encoding)(*(data++)); + + // Action table is immediately after the call site table + lsda.action_table = data; + uintptr_t callsite_size = (uintptr_t)read_uleb128(&data); + lsda.action_table = data + callsite_size; + // Call site table is immediately after the header + lsda.call_site_table = (dw_eh_ptr_t)data; + + + return lsda; +} + +/** + * Structure representing an action to be performed while unwinding. This + * contains the address that should be unwound to and the action record that + * provoked this action. + */ +struct dwarf_eh_action +{ + /** + * The address that this action directs should be the new program counter + * value after unwinding. + */ + dw_eh_ptr_t landing_pad; + /// The address of the action record. + dw_eh_ptr_t action_record; +}; + +/** + * Look up the landing pad that corresponds to the current invoke. + * Returns true if record exists. The context is provided by the generic + * unwind library and the lsda should be the result of a call to parse_lsda(). + * + * The action record is returned via the result parameter. + */ +static bool dwarf_eh_find_callsite(struct _Unwind_Context *context, + struct dwarf_eh_lsda *lsda, + struct dwarf_eh_action *result) +{ + result->action_record = 0; + result->landing_pad = 0; + // The current instruction pointer offset within the region + uint64_t ip = _Unwind_GetIP(context) - _Unwind_GetRegionStart(context); + unsigned char *callsite_table = (unsigned char*)lsda->call_site_table; + + while (callsite_table <= lsda->action_table) + { + // Once again, the layout deviates from the spec. + uint64_t call_site_start, call_site_size, landing_pad, action; + call_site_start = read_value(lsda->callsite_encoding, &callsite_table); + call_site_size = read_value(lsda->callsite_encoding, &callsite_table); + + // Call site entries are sorted, so if we find a call site that's after + // the current instruction pointer then there is no action associated + // with this call and we should unwind straight through this frame + // without doing anything. + if (call_site_start > ip) { break; } + + // Read the address of the landing pad and the action from the call + // site table. + landing_pad = read_value(lsda->callsite_encoding, &callsite_table); + action = read_uleb128(&callsite_table); + + // We should not include the call_site_start (beginning of the region) + // address in the ip range. For each call site: + // + // address1: call proc + // address2: next instruction + // + // The call stack contains address2 and not address1, address1 can be + // at the end of another EH region. + if (call_site_start < ip && ip <= call_site_start + call_site_size) + { + if (action) + { + // Action records are 1-biased so both no-record and zeroth + // record can be stored. + result->action_record = lsda->action_table + action - 1; + } + // No landing pad means keep unwinding. + if (landing_pad) + { + // Landing pad is the offset from the value in the header + result->landing_pad = lsda->landing_pads + landing_pad; + } + return true; + } + } + return false; +} + +/// Defines an exception class from 8 bytes (endian independent) +#define EXCEPTION_CLASS(a,b,c,d,e,f,g,h) \ + (((uint64_t)a << 56) +\ + ((uint64_t)b << 48) +\ + ((uint64_t)c << 40) +\ + ((uint64_t)d << 32) +\ + ((uint64_t)e << 24) +\ + ((uint64_t)f << 16) +\ + ((uint64_t)g << 8) +\ + ((uint64_t)h)) + +#define GENERIC_EXCEPTION_CLASS(e,f,g,h) \ + ((uint32_t)e << 24) +\ + ((uint32_t)f << 16) +\ + ((uint32_t)g << 8) +\ + ((uint32_t)h) Copied: vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/exception.cc (from r227972, vendor/libcxxrt/dist/exception.cc) ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ vendor/libcxxrt/1be67aa8295314fb794c4e933d9bb7c7c33e0ca4/exception.cc Fri Nov 25 15:48:30 2011 (r227973, copy of r227972, vendor/libcxxrt/dist/exception.cc) @@ -0,0 +1,1421 @@ +#include <stdlib.h> +#include <dlfcn.h> +#include <stdio.h> +#include <string.h> +#include <stdint.h> +#include <pthread.h> +#include "typeinfo.h" +#include "dwarf_eh.h" +#include "cxxabi.h" + +using namespace ABI_NAMESPACE; + +/** + * Saves the result of the landing pad that we have found. For ARM, this is + * stored in the generic unwind structure, while on other platforms it is + * stored in the C++ exception. + */ +static void saveLandingPad(struct _Unwind_Context *context, + struct _Unwind_Exception *ucb, + struct __cxa_exception *ex, + int selector, + dw_eh_ptr_t landingPad) +{ +#ifdef __arm__ + // On ARM, we store the saved exception in the generic part of the structure + ucb->barrier_cache.sp = _Unwind_GetGR(context, 13); + ucb->barrier_cache.bitpattern[1] = (uint32_t)selector; + ucb->barrier_cache.bitpattern[3] = (uint32_t)landingPad; +#endif + // Cache the results for the phase 2 unwind, if we found a handler + // and this is not a foreign exception. + if (ex) + { + ex->handlerSwitchValue = selector; + ex->catchTemp = landingPad; + } +} + +/** + * Loads the saved landing pad. Returns 1 on success, 0 on failure. + */ +static int loadLandingPad(struct _Unwind_Context *context, + struct _Unwind_Exception *ucb, + struct __cxa_exception *ex, + unsigned long *selector, + dw_eh_ptr_t *landingPad) +{ +#ifdef __arm__ + *selector = ucb->barrier_cache.bitpattern[1]; + *landingPad = (dw_eh_ptr_t)ucb->barrier_cache.bitpattern[3]; + return 1; +#else + if (ex) + { + *selector = ex->handlerSwitchValue; + *landingPad = (dw_eh_ptr_t)ex->catchTemp; + return 0; + } + return 0; +#endif +} + +static inline _Unwind_Reason_Code continueUnwinding(struct _Unwind_Exception *ex, + struct _Unwind_Context *context) +{ +#ifdef __arm__ + if (__gnu_unwind_frame(ex, context) != _URC_OK) { return _URC_FAILURE; } +#endif + return _URC_CONTINUE_UNWIND; +} + + +extern "C" void __cxa_free_exception(void *thrown_exception); +extern "C" void __cxa_free_dependent_exception(void *thrown_exception); +extern "C" void* __dynamic_cast(const void *sub, + const __class_type_info *src, + const __class_type_info *dst, + ptrdiff_t src2dst_offset); + +/** + * The type of a handler that has been found. + */ +typedef enum +{ + /** No handler. */ + handler_none, + /** + * A cleanup - the exception will propagate through this frame, but code + * must be run when this happens. + */ + handler_cleanup, + /** + * A catch statement. The exception will not propagate past this frame + * (without an explicit rethrow). + */ + handler_catch +} handler_type; + +/** + * Per-thread info required by the runtime. We store a single structure + * pointer in thread-local storage, because this tends to be a scarce resource + * and it's impolite to steal all of it and not leave any for the rest of the + * program. + * + * Instances of this structure are allocated lazily - at most one per thread - + * and are destroyed on thread termination. + */ +struct __cxa_thread_info +{ + /** The termination handler for this thread. */ + terminate_handler terminateHandler; + /** The unexpected exception handler for this thread. */ + unexpected_handler unexpectedHandler; + /** + * The number of emergency buffers held by this thread. This is 0 in + * normal operation - the emergency buffers are only used when malloc() + * fails to return memory for allocating an exception. Threads are not + * permitted to hold more than 4 emergency buffers (as per recommendation + * in ABI spec [3.3.1]). + */ + int emergencyBuffersHeld; + /** + * The exception currently running in a cleanup. + */ + _Unwind_Exception *currentCleanup; + /** + * The public part of this structure, accessible from outside of this + * module. + */ + __cxa_eh_globals globals; +}; +/** + * Dependent exception. This + */ +struct __cxa_dependent_exception +{ +#if __LP64__ + void *primaryException; +#endif + std::type_info *exceptionType; + void (*exceptionDestructor) (void *); + unexpected_handler unexpectedHandler; + terminate_handler terminateHandler; + __cxa_exception *nextException; + int handlerCount; +#ifdef __arm__ + _Unwind_Exception *nextCleanup; + int cleanupCount; +#endif + int handlerSwitchValue; + const char *actionRecord; + const char *languageSpecificData; + void *catchTemp; + void *adjustedPtr; +#if !__LP64__ + void *primaryException; +#endif + _Unwind_Exception unwindHeader; +}; + + +namespace std +{ + void unexpected(); + class exception + { + public: + virtual ~exception() throw(); + virtual const char* what() const throw(); + }; + +} + +extern "C" std::type_info *__cxa_current_exception_type(); + +/** + * Class of exceptions to distinguish between this and other exception types. + * + * The first four characters are the vendor ID. Currently, we use GNUC, + * because we aim for ABI-compatibility with the GNU implementation, and + * various checks may test for equality of the class, which is incorrect. + */ +static const uint64_t exception_class = + EXCEPTION_CLASS('G', 'N', 'U', 'C', 'C', '+', '+', '\0'); +/** + * Class used for dependent exceptions. + */ +static const uint64_t dependent_exception_class = + EXCEPTION_CLASS('G', 'N', 'U', 'C', 'C', '+', '+', '\x01'); +/** + * The low four bytes of the exception class, indicating that we conform to the + * Itanium C++ ABI. This is currently unused, but should be used in the future + * if we change our exception class, to allow this library and libsupc++ to be + * linked to the same executable and both to interoperate. + */ +static const uint32_t abi_exception_class = + GENERIC_EXCEPTION_CLASS('C', '+', '+', '\0'); + +static bool isCXXException(uint64_t cls) +{ + return (cls == exception_class) || (cls == dependent_exception_class); +} + +static bool isDependentException(uint64_t cls) +{ + return cls == dependent_exception_class; +} + +static __cxa_exception *exceptionFromPointer(void *ex) +{ + return (__cxa_exception*)((char*)ex - + offsetof(struct __cxa_exception, unwindHeader)); +} +static __cxa_exception *realExceptionFromException(__cxa_exception *ex) +{ + if (!isDependentException(ex->unwindHeader.exception_class)) { return ex; } + return ((__cxa_exception*)(((__cxa_dependent_exception*)ex)->primaryException))-1; +} + + +namespace std +{ + // Forward declaration of standard library terminate() function used to + // abort execution. + void terminate(void); +} + +using namespace ABI_NAMESPACE; + + + +/** The global termination handler. */ +static terminate_handler terminateHandler = abort; +/** The global unexpected exception handler. */ +static unexpected_handler unexpectedHandler = std::terminate; + +/** Key used for thread-local data. */ +static pthread_key_t eh_key; + + +/** + * Cleanup function, allowing foreign exception handlers to correctly destroy + * this exception if they catch it. + */ +static void exception_cleanup(_Unwind_Reason_Code reason, + struct _Unwind_Exception *ex) +{ + __cxa_free_exception((void*)ex); +} +static void dependent_exception_cleanup(_Unwind_Reason_Code reason, + struct _Unwind_Exception *ex) +{ + + __cxa_free_dependent_exception((void*)ex); +} + +/** + * Recursively walk a list of exceptions and delete them all in post-order. + */ +static void free_exception_list(__cxa_exception *ex) +{ + if (0 != ex->nextException) + { + free_exception_list(ex->nextException); + } + // __cxa_free_exception() expects to be passed the thrown object, which + // immediately follows the exception, not the exception itself + __cxa_free_exception(ex+1); +} + +/** + * Cleanup function called when a thread exists to make certain that all of the + * per-thread data is deleted. + */ +static void thread_cleanup(void* thread_info) +{ + __cxa_thread_info *info = (__cxa_thread_info*)thread_info; + if (info->globals.caughtExceptions) + { + free_exception_list(info->globals.caughtExceptions); + } + free(thread_info); +} + + +/** + * Once control used to protect the key creation. + */ +static pthread_once_t once_control = PTHREAD_ONCE_INIT; + +/** + * Initialise eh_key. + */ +static void init_key(void) +{ + pthread_key_create(&eh_key, thread_cleanup); +} + +/** + * Returns the thread info structure, creating it if it is not already created. + */ +static __cxa_thread_info *thread_info() +{ + pthread_once(&once_control, init_key); + __cxa_thread_info *info = (__cxa_thread_info*)pthread_getspecific(eh_key); + if (0 == info) + { + info = (__cxa_thread_info*)calloc(1, sizeof(__cxa_thread_info)); + pthread_setspecific(eh_key, info); + } + return info; +} +/** + * Fast version of thread_info(). May fail if thread_info() is not called on + * this thread at least once already. + */ +static __cxa_thread_info *thread_info_fast() +{ *** DIFF OUTPUT TRUNCATED AT 1000 LINES ***
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