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authorliukangcc <[email protected]>2021-09-03 11:38:48 +0800
committerliukangcc <[email protected]>2021-09-16 09:51:33 +0800
commita3541b2a243bdf1cc49029b696b217ce752199c7 (patch)
treeed7bd0398a322fb597938f3fb476909a7cc66606 /components/cplusplus/cpp11/emutls.c
parentdca7dcb42a44249abbe6c36ce2a69355e60d1f79 (diff)
[update] support armclang and c++11.
Diffstat (limited to 'components/cplusplus/cpp11/emutls.c')
-rw-r--r--components/cplusplus/cpp11/emutls.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/components/cplusplus/cpp11/emutls.c b/components/cplusplus/cpp11/emutls.c
new file mode 100644
index 0000000000..576888f16f
--- /dev/null
+++ b/components/cplusplus/cpp11/emutls.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date Author Notes
+ * 2021-04-27 peterfan Add copyright header.
+ */
+
+/* ===---------- 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 <pthread.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define COMPILE_TIME_ASSERT(x)
+
+extern int pthread_key_create(pthread_key_t *key, void (*destructor)(void *));
+extern int pthread_key_delete(pthread_key_t key);
+extern void *pthread_getspecific(pthread_key_t key);
+extern int pthread_setspecific(pthread_key_t key, const void *value);
+
+/* 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
+
+/* 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
+{
+ size_t size; /* size of the object in bytes */
+ size_t 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;
+
+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 = 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
+}
+
+/* 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. */
+ typedef unsigned int gcc_word __attribute__((mode(word)));
+ typedef unsigned int gcc_pointer __attribute__((mode(pointer)));
+ COMPILE_TIME_ASSERT(sizeof(size_t) == sizeof(gcc_word));
+ 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;
+ if (align < sizeof(void *))
+ align = sizeof(void *);
+ /* Make sure that align is power of 2. */
+ if ((align & (align - 1)) != 0)
+ abort();
+
+ void *base = emutls_memalign_alloc(align, size);
+ if (control->value)
+ memcpy(base, control->value, size);
+ else
+ memset(base, 0, size);
+ return base;
+}
+
+static pthread_mutex_t emutls_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static size_t emutls_num_object = 0; /* number of allocated TLS objects */
+
+typedef struct emutls_address_array
+{
+ uintptr_t size; /* number of elements in the 'data' array */
+ void *data[];
+} emutls_address_array;
+
+static pthread_key_t emutls_pthread_key;
+
+static void emutls_key_destructor(void *ptr)
+{
+ emutls_address_array *array = (emutls_address_array *)ptr;
+ uintptr_t i;
+ for (i = 0; i < array->size; ++i)
+ {
+ if (array->data[i])
+ emutls_memalign_free(array->data[i]);
+ }
+ free(ptr);
+}
+
+static void emutls_init(void)
+{
+ if (pthread_key_create(&emutls_pthread_key, emutls_key_destructor) != 0)
+ abort();
+}
+
+/* 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)
+ {
+ static pthread_once_t once = PTHREAD_ONCE_INIT;
+ pthread_once(&once, emutls_init);
+ pthread_mutex_lock(&emutls_mutex);
+ index = control->object.index;
+ if (!index)
+ {
+ index = ++emutls_num_object;
+ __atomic_store_n(&control->object.index, index, __ATOMIC_RELEASE);
+ }
+ pthread_mutex_unlock(&emutls_mutex);
+ }
+ 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;
+ pthread_setspecific(emutls_pthread_key, (void *)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 one extra slot
+ * to store the data array size.
+ * Round up the emutls_address_array size to multiple of 16.
+ */
+ return ((index + 1 + 15) & ~((uintptr_t)15)) - 1;
+}
+
+/* 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 = pthread_getspecific(emutls_pthread_key);
+ if (array == NULL)
+ {
+ uintptr_t new_size = emutls_new_data_array_size(index);
+ array = calloc(new_size + 1, sizeof(void *));
+ 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 = realloc(array, (new_size + 1) * sizeof(void *));
+ 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((__emutls_control *)control);
+ emutls_address_array *array = emutls_get_address_array(index);
+ if (array->data[index - 1] == NULL)
+ array->data[index - 1] = emutls_allocate_object((__emutls_control *)control);
+ return array->data[index - 1];
+}