From: Jacek Caban <jacek@codeweavers.com> --- libs/compiler-rt/Makefile.in | 1 + libs/compiler-rt/lib/builtins/emutls.c | 392 +++++++++++++++++++++++++ 2 files changed, 393 insertions(+) create mode 100644 libs/compiler-rt/lib/builtins/emutls.c diff --git a/libs/compiler-rt/Makefile.in b/libs/compiler-rt/Makefile.in index fba197ccea1..9cc853b3872 100644 --- a/libs/compiler-rt/Makefile.in +++ b/libs/compiler-rt/Makefile.in @@ -12,6 +12,7 @@ SOURCES = \ lib/builtins/divmodsi4.c \ lib/builtins/divsi3.c \ lib/builtins/divti3.c \ + lib/builtins/emutls.c \ lib/builtins/fixdfdi.c \ lib/builtins/fixsfdi.c \ lib/builtins/fixunsdfdi.c \ diff --git a/libs/compiler-rt/lib/builtins/emutls.c b/libs/compiler-rt/lib/builtins/emutls.c new file mode 100644 index 00000000000..dcb3f7c43c2 --- /dev/null +++ b/libs/compiler-rt/lib/builtins/emutls.c @@ -0,0 +1,392 @@ +/* ===---------- emutls.c - Implements __emutls_get_address ---------------=== + * + * The LLVM Compiler Infrastructure + * + * This file is dual licensed under the MIT and the University of Illinois Open + * Source Licenses. See LICENSE.TXT for details. + * + * ===----------------------------------------------------------------------=== + */ +#include <stdint.h> +#include <stdlib.h> +#include <string.h> + +#include "int_lib.h" +#include "int_util.h" + +#ifdef __BIONIC__ +/* There are 4 pthread key cleanup rounds on Bionic. Delay emutls deallocation + to round 2. We need to delay deallocation because: + - Android versions older than M lack __cxa_thread_atexit_impl, so apps + use a pthread key destructor to call C++ destructors. + - Apps might use __thread/thread_local variables in pthread destructors. + We can't wait until the final two rounds, because jemalloc needs two rounds + after the final malloc/free call to free its thread-specific data (see + https://reviews.llvm.org/D46978#1107507). */ +#define EMUTLS_SKIP_DESTRUCTOR_ROUNDS 1 +#else +#define EMUTLS_SKIP_DESTRUCTOR_ROUNDS 0 +#endif + +typedef struct emutls_address_array { + uintptr_t skip_destructor_rounds; + uintptr_t size; /* number of elements in the 'data' array */ + void* data[]; +} emutls_address_array; + +static void emutls_shutdown(emutls_address_array *array); + +#ifndef _WIN32 + +#include <pthread.h> + +static pthread_mutex_t emutls_mutex = PTHREAD_MUTEX_INITIALIZER; +static pthread_key_t emutls_pthread_key; + +typedef unsigned int gcc_word __attribute__((mode(word))); +typedef unsigned int gcc_pointer __attribute__((mode(pointer))); + +/* Default is not to use posix_memalign, so systems like Android + * can use thread local data without heavier POSIX memory allocators. + */ +#ifndef EMUTLS_USE_POSIX_MEMALIGN +#define EMUTLS_USE_POSIX_MEMALIGN 0 +#endif + +static __inline void *emutls_memalign_alloc(size_t align, size_t size) { + void *base; +#if EMUTLS_USE_POSIX_MEMALIGN + if (posix_memalign(&base, align, size) != 0) + abort(); +#else + #define EXTRA_ALIGN_PTR_BYTES (align - 1 + sizeof(void*)) + char* object; + if ((object = (char*)malloc(EXTRA_ALIGN_PTR_BYTES + size)) == NULL) + abort(); + base = (void*)(((uintptr_t)(object + EXTRA_ALIGN_PTR_BYTES)) + & ~(uintptr_t)(align - 1)); + + ((void**)base)[-1] = object; +#endif + return base; +} + +static __inline void emutls_memalign_free(void *base) { +#if EMUTLS_USE_POSIX_MEMALIGN + free(base); +#else + /* The mallocated address is in ((void**)base)[-1] */ + free(((void**)base)[-1]); +#endif +} + +static __inline void emutls_setspecific(emutls_address_array *value) { + pthread_setspecific(emutls_pthread_key, (void*) value); +} + +static __inline emutls_address_array* emutls_getspecific() { + return (emutls_address_array*) pthread_getspecific(emutls_pthread_key); +} + +static void emutls_key_destructor(void* ptr) { + emutls_address_array *array = (emutls_address_array*)ptr; + if (array->skip_destructor_rounds > 0) { + /* emutls is deallocated using a pthread key destructor. These + * destructors are called in several rounds to accommodate destructor + * functions that (re)initialize key values with pthread_setspecific. + * Delay the emutls deallocation to accommodate other end-of-thread + * cleanup tasks like calling thread_local destructors (e.g. the + * __cxa_thread_atexit fallback in libc++abi). + */ + array->skip_destructor_rounds--; + emutls_setspecific(array); + } else { + emutls_shutdown(array); + free(ptr); + } +} + +static __inline void emutls_init(void) { + if (pthread_key_create(&emutls_pthread_key, emutls_key_destructor) != 0) + abort(); +} + +static __inline void emutls_init_once(void) { + static pthread_once_t once = PTHREAD_ONCE_INIT; + pthread_once(&once, emutls_init); +} + +static __inline void emutls_lock() { + pthread_mutex_lock(&emutls_mutex); +} + +static __inline void emutls_unlock() { + pthread_mutex_unlock(&emutls_mutex); +} + +#else /* _WIN32 */ + +#include <windows.h> +#include <malloc.h> +#include <stdio.h> +#include <assert.h> + +static LPCRITICAL_SECTION emutls_mutex; +static DWORD emutls_tls_index = TLS_OUT_OF_INDEXES; + +typedef uintptr_t gcc_word; +typedef void * gcc_pointer; + +static void win_error(DWORD last_err, const char *hint) { + char *buffer = NULL; + if (FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | + FORMAT_MESSAGE_FROM_SYSTEM | + FORMAT_MESSAGE_MAX_WIDTH_MASK, + NULL, last_err, 0, (LPSTR)&buffer, 1, NULL)) { + fprintf(stderr, "Windows error: %s\n", buffer); + } else { + fprintf(stderr, "Unkown Windows error: %s\n", hint); + } + LocalFree(buffer); +} + +static __inline void win_abort(DWORD last_err, const char *hint) { + win_error(last_err, hint); + abort(); +} + +static __inline void *emutls_memalign_alloc(size_t align, size_t size) { + void *base = _aligned_malloc(size, align); + if (!base) + win_abort(GetLastError(), "_aligned_malloc"); + return base; +} + +static __inline void emutls_memalign_free(void *base) { + _aligned_free(base); +} + +static void emutls_exit(void) { + if (emutls_mutex) { + DeleteCriticalSection(emutls_mutex); + _aligned_free(emutls_mutex); + emutls_mutex = NULL; + } + if (emutls_tls_index != TLS_OUT_OF_INDEXES) { + emutls_shutdown((emutls_address_array*)TlsGetValue(emutls_tls_index)); + TlsFree(emutls_tls_index); + emutls_tls_index = TLS_OUT_OF_INDEXES; + } +} + +#pragma warning (push) +#pragma warning (disable : 4100) +static BOOL CALLBACK emutls_init(PINIT_ONCE p0, PVOID p1, PVOID *p2) { + emutls_mutex = (LPCRITICAL_SECTION)_aligned_malloc(sizeof(CRITICAL_SECTION), 16); + if (!emutls_mutex) { + win_error(GetLastError(), "_aligned_malloc"); + return FALSE; + } + InitializeCriticalSection(emutls_mutex); + + emutls_tls_index = TlsAlloc(); + if (emutls_tls_index == TLS_OUT_OF_INDEXES) { + emutls_exit(); + win_error(GetLastError(), "TlsAlloc"); + return FALSE; + } + atexit(&emutls_exit); + return TRUE; +} + +static __inline void emutls_init_once(void) { + static INIT_ONCE once; + InitOnceExecuteOnce(&once, emutls_init, NULL, NULL); +} + +static __inline void emutls_lock() { + EnterCriticalSection(emutls_mutex); +} + +static __inline void emutls_unlock() { + LeaveCriticalSection(emutls_mutex); +} + +static __inline void emutls_setspecific(emutls_address_array *value) { + if (TlsSetValue(emutls_tls_index, (LPVOID) value) == 0) + win_abort(GetLastError(), "TlsSetValue"); +} + +static __inline emutls_address_array* emutls_getspecific() { + LPVOID value = TlsGetValue(emutls_tls_index); + if (value == NULL) { + const DWORD err = GetLastError(); + if (err != ERROR_SUCCESS) + win_abort(err, "TlsGetValue"); + } + return (emutls_address_array*) value; +} + +/* Provide atomic load/store functions for emutls_get_index if built with MSVC. + */ +#if !defined(__ATOMIC_RELEASE) +#include <intrin.h> + +enum { __ATOMIC_ACQUIRE = 2, __ATOMIC_RELEASE = 3 }; + +static __inline uintptr_t __atomic_load_n(void *ptr, unsigned type) { + assert(type == __ATOMIC_ACQUIRE); + // These return the previous value - but since we do an OR with 0, + // it's equivalent to a plain load. +#ifdef _WIN64 + return InterlockedOr64(ptr, 0); +#else + return InterlockedOr(ptr, 0); +#endif +} + +static __inline void __atomic_store_n(void *ptr, uintptr_t val, unsigned type) { + assert(type == __ATOMIC_RELEASE); + InterlockedExchangePointer((void *volatile *)ptr, (void *)val); +} + +#endif /* __ATOMIC_RELEASE */ + +#pragma warning (pop) + +#endif /* _WIN32 */ + +static size_t emutls_num_object = 0; /* number of allocated TLS objects */ + +/* Free the allocated TLS data + */ +static void emutls_shutdown(emutls_address_array *array) { + if (array) { + uintptr_t i; + for (i = 0; i < array->size; ++i) { + if (array->data[i]) + emutls_memalign_free(array->data[i]); + } + } +} + +/* For every TLS variable xyz, + * there is one __emutls_control variable named __emutls_v.xyz. + * If xyz has non-zero initial value, __emutls_v.xyz's "value" + * will point to __emutls_t.xyz, which has the initial value. + */ +typedef struct __emutls_control { + /* Must use gcc_word here, instead of size_t, to match GCC. When + gcc_word is larger than size_t, the upper extra bits are all + zeros. We can use variables of size_t to operate on size and + align. */ + gcc_word size; /* size of the object in bytes */ + gcc_word align; /* alignment of the object in bytes */ + union { + uintptr_t index; /* data[index-1] is the object address */ + void* address; /* object address, when in single thread env */ + } object; + void* value; /* null or non-zero initial value for the object */ +} __emutls_control; + +/* Emulated TLS objects are always allocated at run-time. */ +static __inline void *emutls_allocate_object(__emutls_control *control) { + /* Use standard C types, check with gcc's emutls.o. */ + COMPILE_TIME_ASSERT(sizeof(uintptr_t) == sizeof(gcc_pointer)); + COMPILE_TIME_ASSERT(sizeof(uintptr_t) == sizeof(void*)); + + size_t size = control->size; + size_t align = control->align; + void* base; + if (align < sizeof(void*)) + align = sizeof(void*); + /* Make sure that align is power of 2. */ + if ((align & (align - 1)) != 0) + abort(); + + base = emutls_memalign_alloc(align, size); + if (control->value) + memcpy(base, control->value, size); + else + memset(base, 0, size); + return base; +} + + +/* Returns control->object.index; set index if not allocated yet. */ +static __inline uintptr_t emutls_get_index(__emutls_control *control) { + uintptr_t index = __atomic_load_n(&control->object.index, __ATOMIC_ACQUIRE); + if (!index) { + emutls_init_once(); + emutls_lock(); + index = control->object.index; + if (!index) { + index = ++emutls_num_object; + __atomic_store_n(&control->object.index, index, __ATOMIC_RELEASE); + } + emutls_unlock(); + } + return index; +} + +/* Updates newly allocated thread local emutls_address_array. */ +static __inline void emutls_check_array_set_size(emutls_address_array *array, + uintptr_t size) { + if (array == NULL) + abort(); + array->size = size; + emutls_setspecific(array); +} + +/* Returns the new 'data' array size, number of elements, + * which must be no smaller than the given index. + */ +static __inline uintptr_t emutls_new_data_array_size(uintptr_t index) { + /* Need to allocate emutls_address_array with extra slots + * to store the header. + * Round up the emutls_address_array size to multiple of 16. + */ + uintptr_t header_words = sizeof(emutls_address_array) / sizeof(void *); + return ((index + header_words + 15) & ~((uintptr_t)15)) - header_words; +} + +/* Returns the size in bytes required for an emutls_address_array with + * N number of elements for data field. + */ +static __inline uintptr_t emutls_asize(uintptr_t N) { + return N * sizeof(void *) + sizeof(emutls_address_array); +} + +/* Returns the thread local emutls_address_array. + * Extends its size if necessary to hold address at index. + */ +static __inline emutls_address_array * +emutls_get_address_array(uintptr_t index) { + emutls_address_array* array = emutls_getspecific(); + if (array == NULL) { + uintptr_t new_size = emutls_new_data_array_size(index); + array = (emutls_address_array*) malloc(emutls_asize(new_size)); + if (array) { + memset(array->data, 0, new_size * sizeof(void*)); + array->skip_destructor_rounds = EMUTLS_SKIP_DESTRUCTOR_ROUNDS; + } + emutls_check_array_set_size(array, new_size); + } else if (index > array->size) { + uintptr_t orig_size = array->size; + uintptr_t new_size = emutls_new_data_array_size(index); + array = (emutls_address_array*) realloc(array, emutls_asize(new_size)); + if (array) + memset(array->data + orig_size, 0, + (new_size - orig_size) * sizeof(void*)); + emutls_check_array_set_size(array, new_size); + } + return array; +} + +void* __emutls_get_address(void* control) { + uintptr_t index = emutls_get_index(control); + emutls_address_array* array = emutls_get_address_array(index--); + if (array->data[index] == NULL) + array->data[index] = emutls_allocate_object(control); + return array->data[index]; +} -- GitLab https://gitlab.winehq.org/wine/wine/-/merge_requests/10160