From 05d51bcf07d0ec1c40785b4a860fd917410b4be1 Mon Sep 17 00:00:00 2001 From: Logan Chien Date: Sat, 10 May 2014 00:42:10 +0000 Subject: Implement ARM EHABI exception handling. This commit implements the ARM zero-cost exception handling support for libc++abi. git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@208466 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/cxxabi.h | 4 ++ include/unwind.h | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++----- 2 files changed, 144 insertions(+), 13 deletions(-) (limited to 'include') diff --git a/include/cxxabi.h b/include/cxxabi.h index 66ef6d4..82a7e74 100644 --- a/include/cxxabi.h +++ b/include/cxxabi.h @@ -44,6 +44,10 @@ extern LIBCXXABI_NORETURN void __cxa_throw(void * thrown_exception, extern void * __cxa_get_exception_ptr(void * exceptionObject) throw(); extern void * __cxa_begin_catch(void * exceptionObject) throw(); extern void __cxa_end_catch(); +#if __arm__ +extern bool __cxa_begin_cleanup(void * exceptionObject) throw(); +extern void __cxa_end_cleanup(); +#endif extern std::type_info * __cxa_current_exception_type(); // 2.5.4 Rethrowing Exceptions diff --git a/include/unwind.h b/include/unwind.h index 673e060..131657d 100644 --- a/include/unwind.h +++ b/include/unwind.h @@ -23,8 +23,16 @@ #define LIBUNWIND_UNAVAIL #endif +#if !defined(__USING_SJLJ_EXCEPTIONS__) && defined(__arm__) && \ + !defined(__ARM_DWARF_EH__) && !defined(__APPLE__) +#define LIBCXXABI_ARM_EHABI 1 +#else +#define LIBCXXABI_ARM_EHABI 0 +#endif + typedef enum { _URC_NO_REASON = 0, + _URC_OK = 0, _URC_FOREIGN_EXCEPTION_CAUGHT = 1, _URC_FATAL_PHASE2_ERROR = 2, _URC_FATAL_PHASE1_ERROR = 3, @@ -32,7 +40,8 @@ typedef enum { _URC_END_OF_STACK = 5, _URC_HANDLER_FOUND = 6, _URC_INSTALL_CONTEXT = 7, - _URC_CONTINUE_UNWIND = 8 + _URC_CONTINUE_UNWIND = 8, + _URC_FAILURE = 9 } _Unwind_Reason_Code; typedef enum { @@ -43,13 +52,69 @@ typedef enum { _UA_END_OF_STACK = 16 // gcc extension to C++ ABI } _Unwind_Action; + +#if LIBCXXABI_ARM_EHABI +typedef uint32_t _Unwind_State; + +static const _Unwind_State _US_VIRTUAL_UNWIND_FRAME = 0; +static const _Unwind_State _US_UNWIND_FRAME_STARTING = 1; +static const _Unwind_State _US_UNWIND_FRAME_RESUME = 2; + +typedef uint32_t _Unwind_EHT_Header; + +struct _Unwind_Control_Block; +typedef struct _Unwind_Control_Block _Unwind_Control_Block; +typedef struct _Unwind_Control_Block _Unwind_Exception; /* Alias */ + +struct _Unwind_Control_Block { + uint64_t exception_class; + void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block*); + + struct { + uint32_t reserved1; + uint32_t reserved2; + uint32_t reserved3; + uint32_t reserved4; + uint32_t reserved5; + } unwinder_cache; + + struct { + uint32_t sp; + uint32_t bitpattern[5]; + } barrier_cache; + + struct { + uint32_t bitpattern[4]; + } cleanup_cache; + + struct { + uint32_t fnstart; + _Unwind_EHT_Header* ehtp; + uint32_t additional; + uint32_t reserved1; + } pr_cache; + + long long int :0; /* Enforce the 8-byte alignment */ +}; + +typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) + (_Unwind_State state, + _Unwind_Exception* exceptionObject, + struct _Unwind_Context* context); + +typedef _Unwind_Reason_Code (*__personality_routine) + (_Unwind_State state, + _Unwind_Exception* exceptionObject, + struct _Unwind_Context* context); +#else struct _Unwind_Context; // opaque struct _Unwind_Exception; // forward declaration +typedef struct _Unwind_Exception _Unwind_Exception; struct _Unwind_Exception { uint64_t exception_class; void (*exception_cleanup)(_Unwind_Reason_Code reason, - struct _Unwind_Exception *exc); + _Unwind_Exception *exc); uintptr_t private_1; // non-zero means forced unwind uintptr_t private_2; // holds sp that phase1 found for phase2 to use #if !__LP64__ @@ -65,7 +130,7 @@ typedef _Unwind_Reason_Code (*_Unwind_Stop_Fn) (int version, _Unwind_Action actions, uint64_t exceptionClass, - struct _Unwind_Exception* exceptionObject, + _Unwind_Exception* exceptionObject, struct _Unwind_Context* context, void* stop_parameter ); @@ -73,8 +138,9 @@ typedef _Unwind_Reason_Code (*__personality_routine) (int version, _Unwind_Action actions, uint64_t exceptionClass, - struct _Unwind_Exception* exceptionObject, + _Unwind_Exception* exceptionObject, struct _Unwind_Context* context); +#endif #ifdef __cplusplus extern "C" { @@ -85,29 +151,90 @@ extern "C" { // #if __USING_SJLJ_EXCEPTIONS__ extern _Unwind_Reason_Code - _Unwind_SjLj_RaiseException(struct _Unwind_Exception *exception_object); -extern void _Unwind_SjLj_Resume(struct _Unwind_Exception *exception_object); + _Unwind_SjLj_RaiseException(_Unwind_Exception *exception_object); +extern void _Unwind_SjLj_Resume(_Unwind_Exception *exception_object); #else extern _Unwind_Reason_Code - _Unwind_RaiseException(struct _Unwind_Exception *exception_object); -extern void _Unwind_Resume(struct _Unwind_Exception *exception_object); + _Unwind_RaiseException(_Unwind_Exception *exception_object); +extern void _Unwind_Resume(_Unwind_Exception *exception_object); #endif -extern void _Unwind_DeleteException(struct _Unwind_Exception *exception_object); +extern void _Unwind_DeleteException(_Unwind_Exception *exception_object); + +#if LIBCXXABI_ARM_EHABI +typedef enum { + _UVRSC_CORE = 0, + _UVRSC_VFP = 1, + _UVRSC_WMMXD = 3, + _UVRSC_WMMXC = 4 +} _Unwind_VRS_RegClass; + +typedef enum { + _UVRSD_UINT32 = 0, + _UVRSD_VFPX = 1, + _UVRSD_UINT64 = 3, + _UVRSD_FLOAT = 4, + _UVRSD_DOUBLE = 5 +} _Unwind_VRS_DataRepresentation; + +typedef enum { + _UVRSR_OK = 0, + _UVRSR_NOT_IMPLEMENTED = 1, + _UVRSR_FAILED = 2 +} _Unwind_VRS_Result; + +extern _Unwind_VRS_Result _Unwind_VRS_Get(_Unwind_Context* context, + _Unwind_VRS_RegClass regclass, + uint32_t regno, + _Unwind_VRS_DataRepresentation representation, + void *valuep); + +extern _Unwind_VRS_Result _Unwind_VRS_Set(_Unwind_Context* context, + _Unwind_VRS_RegClass regclass, + uint32_t regno, + _Unwind_VRS_DataRepresentation representation, + void *valuep); + +static inline uintptr_t _Unwind_GetGR(struct _Unwind_Context* context, + int index) { + uintptr_t value = 0; + _Unwind_VRS_Get(context, _UVRSC_CORE, (uint32_t)index, _UVRSD_UINT32, &value); + return value; +} + +static inline void _Unwind_SetGR(struct _Unwind_Context* context, int index, + uintptr_t new_value) { + _Unwind_VRS_Set(context, _UVRSC_CORE, (uint32_t)index, + _UVRSD_UINT32, &new_value); +} + +static inline uintptr_t _Unwind_GetIP(struct _Unwind_Context* context) { + // remove the thumb-bit before returning + return (_Unwind_GetGR(context, 15) & (~(uintptr_t)0x1)); +} + +static inline void _Unwind_SetIP(struct _Unwind_Context* context, + uintptr_t new_value) { + uintptr_t thumb_bit = _Unwind_GetGR(context, 15) & ((uintptr_t)0x1); + _Unwind_SetGR(context, 15, new_value | thumb_bit); +} +#else extern uintptr_t _Unwind_GetGR(struct _Unwind_Context *context, int index); extern void _Unwind_SetGR(struct _Unwind_Context *context, int index, uintptr_t new_value); extern uintptr_t _Unwind_GetIP(struct _Unwind_Context *context); extern void _Unwind_SetIP(struct _Unwind_Context *, uintptr_t new_value); +#endif + extern uintptr_t _Unwind_GetRegionStart(struct _Unwind_Context *context); extern uintptr_t _Unwind_GetLanguageSpecificData(struct _Unwind_Context *context); #if __USING_SJLJ_EXCEPTIONS__ extern _Unwind_Reason_Code - _Unwind_SjLj_ForcedUnwind(struct _Unwind_Exception *exception_object, + _Unwind_SjLj_ForcedUnwind(_Unwind_Exception *exception_object, _Unwind_Stop_Fn stop, void *stop_parameter); #else extern _Unwind_Reason_Code - _Unwind_ForcedUnwind(struct _Unwind_Exception *exception_object, + _Unwind_ForcedUnwind(_Unwind_Exception *exception_object, _Unwind_Stop_Fn stop, void *stop_parameter); #endif @@ -126,10 +253,10 @@ extern void _Unwind_SjLj_Unregister(_Unwind_FunctionContext_t fc); // #if __USING_SJLJ_EXCEPTIONS__ extern _Unwind_Reason_Code - _Unwind_SjLj_Resume_or_Rethrow(struct _Unwind_Exception *exception_object); + _Unwind_SjLj_Resume_or_Rethrow(_Unwind_Exception *exception_object); #else extern _Unwind_Reason_Code - _Unwind_Resume_or_Rethrow(struct _Unwind_Exception *exception_object); + _Unwind_Resume_or_Rethrow(_Unwind_Exception *exception_object); #endif // _Unwind_Backtrace() is a gcc extension that walks the stack and calls the -- cgit v1.2.3