(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.

1 files changed, 273 insertions, 0 deletions

diff --git a/sysdeps/generic/libc-tls.c b/sysdeps/generic/libc-tls.c
new file mode 100644
index 0000000..b5ecc36
--- /dev/null
+++ b/sysdeps/generic/libc-tls.c
@@ -0,0 +1,273 @@
+/* Initialization code for TLS in statically linked application.
+   Copyright (C) 2002, 2003 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.  */
+
+#include <errno.h>
+#include <ldsodefs.h>
+#include <tls.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/param.h>
+
+
+#ifdef SHARED
+ #error makefile bug, this file is for static only
+#endif
+
+#ifdef USE_TLS
+extern ElfW(Phdr) *_dl_phdr;
+extern size_t _dl_phnum;
+
+
+/* DTV with just one element plus overhead.  */
+static dtv_t static_dtv[3];
+
+
+static struct
+{
+  struct dtv_slotinfo_list si;
+  /* The dtv_slotinfo_list data structure does not include the actual
+     information since it is defined as an array of size zero.  We define
+     here the necessary entries.  Note that it is not important whether
+     there is padding or not since we will always access the information
+     through the 'si' element.  */
+  struct dtv_slotinfo info[2 + TLS_SLOTINFO_SURPLUS];
+} static_slotinfo;
+
+/* Fake link map for the application.  */
+static struct link_map static_map;
+
+
+/* Highest dtv index currently needed.  */
+size_t _dl_tls_max_dtv_idx;
+/* Flag signalling whether there are gaps in the module ID allocation.  */
+bool _dl_tls_dtv_gaps;
+/* Information about the dtv slots.  */
+struct dtv_slotinfo_list *_dl_tls_dtv_slotinfo_list;
+/* Number of modules in the static TLS block.  */
+size_t _dl_tls_static_nelem;
+/* Size of the static TLS block.  */
+size_t _dl_tls_static_size;
+/* Size actually allocated in the static TLS block.  */
+size_t _dl_tls_static_used;
+/* Alignment requirement of the static TLS block.  */
+size_t _dl_tls_static_align;
+
+/* Generation counter for the dtv.  */
+size_t _dl_tls_generation;
+
+
+/* Additional definitions needed by TLS initialization.  */
+#ifdef TLS_INIT_HELPER
+TLS_INIT_HELPER
+#endif
+
+static inline void
+init_slotinfo (void)
+{
+  /* Create the slotinfo list.  */
+  static_slotinfo.si.len = (((char *) (&static_slotinfo + 1)
+			     - (char *) &static_slotinfo.si.slotinfo[0])
+			    / sizeof static_slotinfo.si.slotinfo[0]);
+  // static_slotinfo.si.next = NULL;	already zero
+
+  /* The slotinfo list.  Will be extended by the code doing dynamic
+     linking.  */
+  GL(dl_tls_max_dtv_idx) = 1;
+  GL(dl_tls_dtv_slotinfo_list) = &static_slotinfo.si;
+}
+
+static inline void
+init_static_tls (size_t memsz, size_t align)
+{
+  /* That is the size of the TLS memory for this object.  The initialized
+     value of _dl_tls_static_size is provided by dl-open.c to request some
+     surplus that permits dynamic loading of modules with IE-model TLS.  */
+  GL(dl_tls_static_size) = roundup (memsz + GL(dl_tls_static_size),
+				    TLS_TCB_ALIGN);
+  GL(dl_tls_static_used) = memsz;
+  /* The alignment requirement for the static TLS block.  */
+  GL(dl_tls_static_align) = align;
+  /* Number of elements in the static TLS block.  */
+  GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx);
+}
+
+void
+__libc_setup_tls (size_t tcbsize, size_t tcbalign)
+{
+  void *tlsblock;
+  size_t memsz = 0;
+  size_t filesz = 0;
+  void *initimage = NULL;
+  size_t align = 0;
+  size_t max_align = tcbalign;
+  size_t tcb_offset;
+  ElfW(Phdr) *phdr;
+
+  /* Look through the TLS segment if there is any.  */
+  if (_dl_phdr != NULL)
+    for (phdr = _dl_phdr; phdr < &_dl_phdr[_dl_phnum]; ++phdr)
+      if (phdr->p_type == PT_TLS)
+	{
+	  /* Remember the values we need.  */
+	  memsz = phdr->p_memsz;
+	  filesz = phdr->p_filesz;
+	  initimage = (void *) phdr->p_vaddr;
+	  align = phdr->p_align;
+	  if (phdr->p_align > max_align)
+	    max_align = phdr->p_align;
+	  break;
+	}
+
+#ifdef TLS_INIT_TP_EXPENSIVE
+  if (memsz == 0 && tcbsize <= TLS_INIT_TCB_SIZE)
+    {
+      /* We do not need a TLS block and no thread descriptor.  */
+# ifdef NONTLS_INIT_TP
+      NONTLS_INIT_TP;
+# endif
+      return;
+    }
+#endif
+
+  /* We have to set up the TCB block which also (possibly) contains
+     'errno'.  Therefore we avoid 'malloc' which might touch 'errno'.
+     Instead we use 'sbrk' which would only uses 'errno' if it fails.
+     In this case we are right away out of memory and the user gets
+     what she/he deserves.
+
+     The initialized value of _dl_tls_static_size is provided by dl-open.c
+     to request some surplus that permits dynamic loading of modules with
+     IE-model TLS.  */
+# if TLS_TCB_AT_TP
+  tcb_offset = roundup (memsz + GL(dl_tls_static_size), tcbalign);
+  tlsblock = __sbrk (tcb_offset + tcbsize + max_align);
+# elif TLS_DTV_AT_TP
+  tcb_offset = roundup (tcbsize, align ?: 1);
+  tlsblock = __sbrk (tcb_offset + memsz + max_align
+		     + TLS_PRE_TCB_SIZE + GL(dl_tls_static_size));
+  tlsblock += TLS_PRE_TCB_SIZE;
+# else
+  /* In case a model with a different layout for the TCB and DTV
+     is defined add another #elif here and in the following #ifs.  */
+#  error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+# endif
+
+  /* Align the TLS block.  */
+  tlsblock = (void *) (((uintptr_t) tlsblock + max_align - 1)
+		       & ~(max_align - 1));
+
+  /* Initialize the dtv.  [0] is the length, [1] the generation counter.  */
+  static_dtv[0].counter = 1;
+  // static_dtv[1].counter = 0;		would be needed if not already done
+
+  /* Initialize the TLS block.  */
+# if TLS_TCB_AT_TP
+  static_dtv[2].pointer = ((char *) tlsblock + tcb_offset
+			   - roundup (memsz, align ?: 1));
+  static_map.l_tls_offset = roundup (memsz, align ?: 1);
+# elif TLS_DTV_AT_TP
+  static_dtv[2].pointer = (char *) tlsblock + tcb_offset;
+  static_map.l_tls_offset = tcb_offset;
+# else
+#  error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+# endif
+  /* sbrk gives us zero'd memory, so we don't need to clear the remainder.  */
+  memcpy (static_dtv[2].pointer, initimage, filesz);
+
+  /* Install the pointer to the dtv.  */
+
+  /* Initialize the thread pointer.  */
+# if TLS_TCB_AT_TP
+  INSTALL_DTV ((char *) tlsblock + tcb_offset, static_dtv);
+
+  const char *lossage = TLS_INIT_TP ((char *) tlsblock + tcb_offset, 0);
+# elif TLS_DTV_AT_TP
+  INSTALL_DTV (tlsblock, static_dtv);
+  const char *lossage = TLS_INIT_TP (tlsblock, 0);
+# else
+#  error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined"
+# endif
+  if (__builtin_expect (lossage != NULL, 0))
+    __libc_fatal (lossage);
+
+  /* We have to create a fake link map which normally would be created
+     by the dynamic linker.  It just has to have enough information to
+     make the TLS routines happy.  */
+  static_map.l_tls_align = align;
+  static_map.l_tls_blocksize = memsz;
+  static_map.l_tls_initimage = initimage;
+  static_map.l_tls_initimage_size = filesz;
+  static_map.l_type = lt_executable;
+  static_map.l_tls_modid = 1;
+
+  init_slotinfo ();
+  // static_slotinfo.si.slotinfo[1].gen = 0; already zero
+  static_slotinfo.si.slotinfo[1].map = &static_map;
+
+  memsz = roundup (memsz, align ?: 1);
+
+# if TLS_TCB_AT_TP
+  memsz += tcbsize;
+# elif TLS_DTV_AT_TP
+  memsz += tcb_offset;
+# endif
+
+  init_static_tls (memsz, MAX (TLS_TCB_ALIGN, max_align));
+}
+
+/* This is called only when the data structure setup was skipped at startup,
+   when there was no need for it then.  Now we have dynamically loaded
+   something needing TLS, or libpthread needs it.  */
+int
+internal_function
+_dl_tls_setup (void)
+{
+  init_slotinfo ();
+  init_static_tls (
+# if TLS_TCB_AT_TP
+		   TLS_TCB_SIZE,
+# else
+		   0,
+# endif
+		   TLS_TCB_ALIGN);
+  return 0;
+}
+
+
+/* This is the minimal initialization function used when libpthread is
+   not used.  */
+void
+__attribute__ ((weak))
+__pthread_initialize_minimal (void)
+{
+  __libc_setup_tls (TLS_INIT_TCB_SIZE, TLS_INIT_TCB_ALIGN);
+}
+
+#elif defined NONTLS_INIT_TP
+
+/* This is the minimal initialization function used when libpthread is
+   not used.  */
+void
+__attribute__ ((weak))
+__pthread_initialize_minimal (void)
+{
+  NONTLS_INIT_TP;
+}
+
+#endif