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diff --git a/nptl/sysdeps/i386/tls.h b/nptl/sysdeps/i386/tls.h
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+/* Definition for thread-local data handling.  linuxthreads/i386 version.
+   Copyright (C) 2002 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	1
+
+#ifndef __ASSEMBLER__
+# 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 require TLS support in the tools.  */
+#ifndef HAVE_TLS_SUPPORT
+# error "TLS support is required."
+#endif
+
+/* Signal that TLS support is available.  */
+#define USE_TLS	1
+
+/* Alignment requirement for the stack.  For IA-32 this is govern by
+   the SSE memory functions.  */
+#define STACK_ALIGN	16
+
+
+#ifndef __ASSEMBLER__
+/* Get system call information.  */
+# include <sysdep.h>
+
+/* The old way: using LDT.  */
+
+/* Structure passed to `modify_ldt', 'set_thread_area', and 'clone' calls.  */
+struct user_desc
+{
+  unsigned int entry_number;
+  unsigned long int base_addr;
+  unsigned int limit;
+  unsigned int seg_32bit:1;
+  unsigned int contents:2;
+  unsigned int read_exec_only:1;
+  unsigned int limit_in_pages:1;
+  unsigned int seg_not_present:1;
+  unsigned int useable:1;
+  unsigned int empty:25;
+};
+
+/* Initializing bit fields is slow.  We speed it up by using a union.  */
+union user_desc_init
+{
+  struct user_desc desc;
+  unsigned int vals[4];
+};
+
+
+/* Get the thread descriptor definition.  */
+# include <nptl/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)
+
+/* Alignment requirements for the TCB.  */
+# define TLS_TCB_ALIGN __alignof__ (struct pthread)
+
+/* 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 *__pd;						      \
+     THREAD_SETMEM (__pd, header.data.dtvp, dtv); })
+
+/* Return dtv of given thread descriptor.  */
+# define GET_DTV(descr) \
+  (((tcbhead_t *) (descr))->dtv)
+
+
+/* Macros to load from and store into segment registers.  */
+# ifndef TLS_GET_GS
+#  define TLS_GET_GS() \
+  ({ int __seg; __asm ("movw %%gs, %w0" : "=q" (__seg)); __seg & 0xffff; })
+# endif
+# ifndef TLS_SET_GS
+#  define TLS_SET_GS(val) \
+  __asm ("movw %w0, %%gs" :: "q" (val))
+# endif
+
+
+# ifndef __NR_set_thread_area
+#  define __NR_set_thread_area 243
+# endif
+# ifndef TLS_FLAG_WRITABLE
+#  define TLS_FLAG_WRITABLE		0x00000001
+# endif
+
+// XXX Enable for the real world.
+#if 0
+# ifndef __ASSUME_SET_THREAD_AREA
+#  error "we need set_thread_area"
+# endif
+#endif
+
+# 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
+
+/* 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(thrdescr, secondcall) \
+  ({ void *_thrdescr = (thrdescr);					      \
+     tcbhead_t *_head = _thrdescr;					      \
+     union user_desc_init _segdescr;					      \
+     int _result;							      \
+									      \
+     _head->tcb = _thrdescr;						      \
+     /* For now the thread descriptor is at the same address.  */	      \
+     _head->self = _thrdescr;						      \
+									      \
+     /* The 'entry_number' field.  Let the kernel pick a value.  */	      \
+     if (secondcall)							      \
+       _segdescr.vals[0] = TLS_GET_GS () >> 3;				      \
+     else								      \
+       _segdescr.vals[0] = -1;						      \
+     /* The 'base_addr' field.  Pointer to the TCB.  */			      \
+     _segdescr.vals[1] = (unsigned long int) _thrdescr;			      \
+     /* The 'limit' field.  We use 4GB which is 0xfffff pages.  */	      \
+     _segdescr.vals[2] = 0xfffff;					      \
+     /* Collapsed value of the bitfield:				      \
+	  .seg_32bit = 1						      \
+	  .contents = 0							      \
+	  .read_exec_only = 0						      \
+	  .limit_in_pages = 1						      \
+	  .seg_not_present = 0						      \
+	  .useable = 1 */						      \
+     _segdescr.vals[3] = 0x51;						      \
+									      \
+     /* Install the TLS.  */						      \
+     asm volatile (TLS_LOAD_EBX						      \
+		   "int $0x80\n\t"					      \
+		   TLS_LOAD_EBX						      \
+		   : "=a" (_result), "=m" (_segdescr.desc.entry_number)	      \
+		   : "0" (__NR_set_thread_area),			      \
+		     TLS_EBX_ARG (&_segdescr.desc), "m" (_segdescr.desc));    \
+									      \
+     if (_result == 0)							      \
+       /* We know the index in the GDT, now load the segment register.	      \
+	  The use of the GDT is described by the value 3 in the lower	      \
+	  three bits of the segment descriptor value.			      \
+									      \
+	  Note that we have to do this even if the numeric value of	      \
+	  the descriptor does not change.  Loading the segment register	      \
+	  causes the segment information from the GDT to be loaded	      \
+	  which is necessary since we have changed it.   */		      \
+       TLS_SET_GS (_segdescr.desc.entry_number * 8 + 3);		      \
+									      \
+     _result; })
+
+
+/* Return the address of the dtv for the current thread.  */
+# define THREAD_DTV() \
+  ({ struct pthread *__pd;						      \
+     THREAD_GETMEM (__pd, header.data.dtvp); })
+
+
+/* Return the thread descriptor for the current thread.
+
+   The contained asm must *not* be marked volatile since otherwise
+   assignments like
+        pthread_descr self = thread_self();
+   do not get optimized away.  */
+# define THREAD_SELF \
+  ({ struct pthread *__self;						      \
+     asm ("movl %%gs:%c1,%0" : "=r" (__self)				      \
+	  : "i" (offsetof (struct pthread, header.data.self))); 	      \
+     __self;})
+
+
+/* Read member of the thread descriptor directly.  */
+# define THREAD_GETMEM(descr, member) \
+  ({ __typeof (descr->member) __value;					      \
+     if (sizeof (__value) == 1)						      \
+       asm ("movb %%gs:%P2,%b0"						      \
+	    : "=q" (__value)						      \
+	    : "0" (0), "i" (offsetof (struct pthread, member)));	      \
+     else if (sizeof (__value) == 4)					      \
+       asm ("movl %%gs:%P1,%0"						      \
+	    : "=r" (__value)						      \
+	    : "i" (offsetof (struct pthread, member)));			      \
+     else								      \
+       {								      \
+	 if (sizeof (__value) != 8)					      \
+	   /* There should not be any value with a size other than 1,	      \
+	      4 or 8.  */						      \
+	   abort ();							      \
+									      \
+	 asm ("movl %%gs:%P1,%%eax\n\t"					      \
+	      "movl %%gs:%P2,%%edx"					      \
+	      : "=A" (__value)						      \
+	      : "i" (offsetof (struct pthread, member)),		      \
+		"i" (offsetof (struct pthread, member) + 4));		      \
+       }								      \
+     __value; })
+
+
+/* Same as THREAD_GETMEM, but the member offset can be non-constant.  */
+# define THREAD_GETMEM_NC(descr, member) \
+  ({ __typeof (descr->member) __value;					      \
+     if (sizeof (__value) == 1)						      \
+       asm ("movb %%gs:(%2),%b0"					      \
+	    : "=q" (__value)						      \
+	    : "0" (0), "r" (offsetof (struct pthread, member)));	      \
+     else if (sizeof (__value) == 4)					      \
+       asm ("movl %%gs:(%1),%0"						      \
+	    : "=r" (__value)						      \
+	    : "r" (offsetof (struct pthread, member)));			      \
+     else								      \
+       {								      \
+	 if (sizeof (__value) != 8)					      \
+	   /* There should not be any value with a size other than 1,	      \
+	      4 or 8.  */						      \
+	   abort ();							      \
+									      \
+	 asm ("movl %%gs:(%1),%%eax\n\t"				      \
+	      "movl %%gs:4(%1),%%edx"					      \
+	      : "=&A" (__value)						      \
+	      : "r" (offsetof (struct pthread, member)));		      \
+       }								      \
+     __value; })
+
+
+/* Same as THREAD_SETMEM, but the member offset can be non-constant.  */
+# define THREAD_SETMEM(descr, member, value) \
+  ({ if (sizeof (value) == 1)						      \
+       asm volatile ("movb %0,%%gs:%P1" :				      \
+		     : "iq" (value),					      \
+		       "i" (offsetof (struct pthread, member)));	      \
+     else if (sizeof (value) == 4)					      \
+       asm volatile ("movl %0,%%gs:%P1" :				      \
+		     : "ir" (value),					      \
+		       "i" (offsetof (struct pthread, member)));	      \
+     else								      \
+       {								      \
+	 if (sizeof (value) != 8)					      \
+	   /* There should not be any value with a size other than 1,	      \
+	      4 or 8.  */						      \
+	   abort ();							      \
+									      \
+	 asm volatile ("movl %%eax,%%gs:%P1\n\n"			      \
+		       "movl %%edx,%%gs:%P2" :				      \
+		       : "A" (value),					      \
+			 "i" (offsetof (struct pthread, member)),	      \
+			 "i" (offsetof (struct pthread, member) + 4));	      \
+       }})
+
+
+/* Set member of the thread descriptor directly.  */
+# define THREAD_SETMEM_NC(descr, member, value) \
+  ({ if (sizeof (value) == 1)						      \
+       asm volatile ("movb %0,%%gs:(%1)" :				      \
+		     : "iq" (value),					      \
+		       "r" (offsetof (struct pthread, member)));	      \
+     else if (sizeof (value) == 4)					      \
+       asm volatile ("movl %0,%%gs:(%1)" :				      \
+		     : "ir" (value),					      \
+		       "r" (offsetof (struct pthread, member)));	      \
+     else								      \
+       {								      \
+	 if (sizeof (value) != 8)					      \
+	   /* There should not be any value with a size other than 1,	      \
+	      4 or 8.  */						      \
+	   abort ();							      \
+									      \
+	 asm volatile ("movl %%eax,%%gs:(%1)\n\t"			      \
+		       "movl %%edx,%%gs:4(%1)" :			      \
+		       : "A" (value),					      \
+			 "r" (offsetof (struct pthread, member)));	      \
+       }})
+
+
+#endif /* __ASSEMBLER__ */
+
+#endif	/* tls.h */