--- /dev/null
+/* Definition for thread-local data handling. linuxthreads/i386 version.
+ Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _TLS_H
+#define _TLS_H
+
+# include <pt-machine.h>
+
+#ifndef __ASSEMBLER__
+# include <stdbool.h>
+# include <stddef.h>
+# include <stdint.h>
+
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ void *pointer;
+} dtv_t;
+
+
+typedef struct
+{
+ void *tcb; /* Pointer to the TCB. Not necessary the
+ thread descriptor used by libpthread. */
+ dtv_t *dtv;
+ void *self; /* Pointer to the thread descriptor. */
+} tcbhead_t;
+#endif
+
+
+/* We can support TLS only if the floating-stack support is available. */
+#if defined FLOATING_STACKS && defined HAVE_TLS_SUPPORT
+
+/* Signal that TLS support is available. */
+//# define USE_TLS 1
+
+# ifndef __ASSEMBLER__
+/* Get system call information. */
+# include <sysdep.h>
+
+
+/* Get the thread descriptor definition. */
+# include <linuxthreads/descr.h>
+
+/* This is the size of the initial TCB. */
+# define TLS_INIT_TCB_SIZE sizeof (tcbhead_t)
+
+/* Alignment requirements for the initial TCB. */
+# define TLS_INIT_TCB_ALIGN __alignof__ (tcbhead_t)
+
+/* This is the size of the TCB. */
+# define TLS_TCB_SIZE sizeof (struct _pthread_descr_struct)
+
+/* Alignment requirements for the TCB. */
+# define TLS_TCB_ALIGN __alignof__ (struct _pthread_descr_struct)
+
+/* The TCB can have any size and the memory following the address the
+ thread pointer points to is unspecified. Allocate the TCB there. */
+# define TLS_TCB_AT_TP 1
+
+
+/* Install the dtv pointer. The pointer passed is to the element with
+ index -1 which contain the length. */
+# define INSTALL_DTV(descr, dtvp) \
+ ((tcbhead_t *) (descr))->dtv = (dtvp) + 1
+
+/* Install new dtv for current thread. */
+# define INSTALL_NEW_DTV(dtv) \
+ ({ struct _pthread_descr_struct *__descr; \
+ THREAD_SETMEM (__descr, p_header.data.dtvp, (dtv)); })
+
+/* Return dtv of given thread descriptor. */
+# define GET_DTV(descr) \
+ (((tcbhead_t *) (descr))->dtv)
+
+# ifdef __PIC__
+# define TLS_EBX_ARG "r"
+# define TLS_LOAD_EBX "xchgl %3, %%ebx\n\t"
+# else
+# define TLS_EBX_ARG "b"
+# define TLS_LOAD_EBX
+# endif
+
+# define TLS_DO_MODIFY_LDT(descr, nr) \
+({ \
+ struct modify_ldt_ldt_s ldt_entry = \
+ { nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
+ 1, 0, 0, 1, 0, 1, 0 }; \
+ int result; \
+ __asm__ __volatile__ (TLS_LOAD_EBX \
+ "int $0x80\n\t" \
+ TLS_LOAD_EBX \
+ : "=a" (result) \
+ : "0" (__NR_modify_ldt), \
+ /* The extra argument with the "m" constraint is necessary \
+ to let the compiler know that we are accessing LDT_ENTRY \
+ here. */ \
+ "m" (ldt_entry), TLS_EBX_ARG (1), "c" (&ldt_entry), \
+ "d" (sizeof (ldt_entry))); \
+ __builtin_expect (result, 0) != 0 ? -1 : nr * 8 + 7; \
+})
+
+# define TLS_DO_SET_THREAD_AREA(descr, secondcall) \
+({ \
+ struct modify_ldt_ldt_s ldt_entry = \
+ { -1, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
+ 1, 0, 0, 1, 0, 1, 0 }; \
+ int result; \
+ if (secondcall) \
+ ldt_entry.entry_number = ({ int _gs; \
+ __asm__ ("movw %%gs, %w0" : "=q" (_gs)); \
+ (_gs & 0xffff) >> 3; }); \
+ __asm__ __volatile__ (TLS_LOAD_EBX \
+ "int $0x80\n\t" \
+ TLS_LOAD_EBX \
+ : "=a" (result), "=m" (ldt_entry.entry_number) \
+ : "0" (__NR_set_thread_area), \
+ /* The extra argument with the "m" constraint is necessary \
+ to let the compiler know that we are accessing LDT_ENTRY \
+ here. */ \
+ TLS_EBX_ARG (&ldt_entry), "m" (ldt_entry)); \
+ __builtin_expect (result, 0) == 0 ? ldt_entry.entry_number * 8 + 3 : -1; \
+})
+
+# ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
+# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
+ TLS_DO_SET_THREAD_AREA (descr, firstcall)
+# elif defined __NR_set_thread_area
+# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
+ ({ int __seg = TLS_DO_SET_THREAD_AREA (descr, secondcall); \
+ __seg == -1 ? TLS_DO_MODIFY_LDT (descr, 0) : __seg; })
+# else
+# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \
+ TLS_DO_MODIFY_LDT ((descr), 0)
+# endif
+
+/* Code to initially initialize the thread pointer. This might need
+ special attention since 'errno' is not yet available and if the
+ operation can cause a failure 'errno' must not be touched. */
+# define TLS_INIT_TP(descr, secondcall) \
+ ({ \
+ void *_descr = (descr); \
+ tcbhead_t *head = _descr; \
+ int __gs; \
+ \
+ head->tcb = _descr; \
+ /* For now the thread descriptor is at the same address. */ \
+ head->self = _descr; \
+ \
+ __gs = TLS_SETUP_GS_SEGMENT (_descr, secondcall); \
+ if (__builtin_expect (__gs, 7) != -1) \
+ { \
+ __asm__ ("movw %w0, %%gs" : : "q" (__gs)); \
+ __gs = 0; \
+ } \
+ __gs; \
+ })
+
+
+/* Return the address of the dtv for the current thread. */
+# define THREAD_DTV() \
+ ({ struct _pthread_descr_struct *__descr; \
+ THREAD_GETMEM (__descr, p_header.data.dtvp); })
+
+# endif /* FLOATING_STACKS && HAVE_TLS_SUPPORT */
+#endif /* __ASSEMBLER__ */
+
+#endif /* tls.h */
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