[v2,05/14] LoongArch: Thread-Local Storage Support

diff --git a/sysdeps/loongarch/dl-tls.h b/sysdeps/loongarch/dl-tls.h
new file mode 100644
index 0000000000..ee7d78a3e9
--- /dev/null
+++ b/sysdeps/loongarch/dl-tls.h
@@ -0,0 +1,46 @@ 
+/* Thread-local storage handling in the ELF dynamic linker.
+   Copyright (C) 2021 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, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* Type used for the representation of TLS information in the GOT.  */
+typedef struct
+{
+  unsigned long int ti_module;
+  unsigned long int ti_offset;
+} tls_index;
+
+/* The thread pointer points to the first static TLS block.  */
+#define TLS_TP_OFFSET 0
+
+/* Dynamic thread vector pointers point to the start of each
+   TLS block.  */
+#define TLS_DTV_OFFSET 0
+
+/* Compute the value for a GOTTPREL reloc.  */
+#define TLS_TPREL_VALUE(sym_map, sym) \
+  ((sym_map)->l_tls_offset + (sym)->st_value - TLS_TP_OFFSET)
+
+/* Compute the value for a DTPREL reloc.  */
+#define TLS_DTPREL_VALUE(sym) ((sym)->st_value - TLS_DTV_OFFSET)
+
+extern void *__tls_get_addr (tls_index *ti);
+
+#define GET_ADDR_OFFSET (ti->ti_offset + TLS_DTV_OFFSET)
+#define __TLS_GET_ADDR(__ti) (__tls_get_addr (__ti) - TLS_DTV_OFFSET)
+
+/* Value used for dtv entries for which the allocation is delayed.  */
+#define TLS_DTV_UNALLOCATED ((void *) -1l)
diff --git a/sysdeps/loongarch/libc-tls.c b/sysdeps/loongarch/libc-tls.c
new file mode 100644
index 0000000000..32e303ecd3
--- /dev/null
+++ b/sysdeps/loongarch/libc-tls.c
@@ -0,0 +1,32 @@ 
+/* Thread-local storage handling in the ELF dynamic linker.
+   Copyright (C) 2021 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, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <csu/libc-tls.c>
+#include <dl-tls.h>
+
+/* On LoongArch, linker optimizations are not required, so __tls_get_addr
+   can be called even in statically linked binaries.  In this case module
+   must be always 1 and PT_TLS segment exist in the binary, otherwise it
+   would not link.  */
+
+void *
+__tls_get_addr (tls_index *ti)
+{
+  dtv_t *dtv = THREAD_DTV ();
+  return (char *) dtv[1].pointer.val + GET_ADDR_OFFSET;
+}
diff --git a/sysdeps/loongarch/nptl/tcb-offsets.sym b/sysdeps/loongarch/nptl/tcb-offsets.sym
new file mode 100644
index 0000000000..7d0c7596e8
--- /dev/null
+++ b/sysdeps/loongarch/nptl/tcb-offsets.sym
@@ -0,0 +1,6 @@ 
+#include <sysdep.h>
+#include <tls.h>
+
+#define thread_offsetof(mem)  (long)(offsetof (struct pthread, mem) - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
+
+MULTIPLE_THREADS_OFFSET		thread_offsetof (header.multiple_threads)
diff --git a/sysdeps/loongarch/nptl/tls.h b/sysdeps/loongarch/nptl/tls.h
new file mode 100644
index 0000000000..3b17e0b7f5
--- /dev/null
+++ b/sysdeps/loongarch/nptl/tls.h
@@ -0,0 +1,138 @@ 
+/* Definition for thread-local data handling.
+   Copyright (C) 2021 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, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _LOONGARCH_TLS_H
+#define _LOONGARCH_TLS_H 1
+
+#include <dl-sysdep.h>
+
+#ifndef __ASSEMBLER__
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <dl-dtv.h>
+
+register void *__thread_self asm("$tp"); /* FIXME */
+#define READ_THREAD_POINTER() ({ __thread_self; })
+
+/* Get system call information.  */
+#include <sysdep.h>
+
+/* The TP points to the start of the thread blocks.  */
+#define TLS_DTV_AT_TP 1
+#define TLS_TCB_AT_TP 0
+
+/* Get the thread descriptor definition.  */
+#include <nptl/descr.h>
+
+typedef struct
+{
+  dtv_t *dtv;
+  void *private;
+} tcbhead_t;
+
+/* This is the size of the initial TCB.  Because our TCB is before the thread
+   pointer, we don't need this.  */
+#define TLS_INIT_TCB_SIZE 0
+
+/* Alignment requirements for the initial TCB.  */
+#define TLS_INIT_TCB_ALIGN __alignof__(struct pthread)
+
+/* This is the size of the TCB.  Because our TCB is before the thread
+   pointer, we don't need this.  */
+#define TLS_TCB_SIZE 0
+
+/* Alignment requirements for the TCB.  */
+#define TLS_TCB_ALIGN __alignof__(struct pthread)
+
+/* This is the size we need before TCB - actually, it includes the TCB.  */
+#define TLS_PRE_TCB_SIZE \
+  (sizeof (struct pthread) \
+   + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+
+/* The thread pointer tp points to the end of the TCB.
+   The pthread_descr structure is immediately in front of the TCB.  */
+#define TLS_TCB_OFFSET 0
+
+/* Install the dtv pointer.  The pointer passed is to the element with
+   index -1 which contain the length.  */
+#define INSTALL_DTV(tcbp, dtvp) (((tcbhead_t *) (tcbp))[-1].dtv = (dtvp) + 1)
+
+/* Install new dtv for current thread.  */
+#define INSTALL_NEW_DTV(dtv) (THREAD_DTV () = (dtv))
+
+/* Return dtv of given thread descriptor.  */
+#define GET_DTV(tcbp) (((tcbhead_t *) (tcbp))[-1].dtv)
+
+/* Code to initially initialize the thread pointer.  */
+#define TLS_INIT_TP(tcbp) \
+  ({ \
+    __thread_self = (char *) tcbp + TLS_TCB_OFFSET; \
+    NULL; \
+  })
+
+/* Return the address of the dtv for the current thread.  */
+#define THREAD_DTV() \
+  (((tcbhead_t *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET))[-1].dtv)
+
+/* Return the thread descriptor for the current thread.  */
+#define THREAD_SELF \
+  ((struct pthread *) (READ_THREAD_POINTER () - TLS_TCB_OFFSET \
+		       - TLS_PRE_TCB_SIZE))
+
+/* Value passed to 'clone' for initialization of the thread register.  */
+#define TLS_DEFINE_INIT_TP(tp, pd) \
+  void *tp = (void *) (pd) + TLS_TCB_OFFSET + TLS_PRE_TCB_SIZE
+
+/* Informs libthread_db that the thread pointer is register 2, which is used
+ * to know how to do THREAD_SELF.  */
+#define DB_THREAD_SELF \
+  REGISTER (64, 64, 2 * 8, -TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE)
+
+/* Access to data in the thread descriptor is easy.  */
+# include <tcb-access.h>
+
+/* l_tls_offset == 0 is perfectly valid, so we have to use some different
+   value to mean unset l_tls_offset.  */
+#define NO_TLS_OFFSET -1
+
+/* Get and set the global scope generation counter in struct pthread.  */
+#define THREAD_GSCOPE_IN_TCB 1
+#define THREAD_GSCOPE_FLAG_UNUSED 0
+#define THREAD_GSCOPE_FLAG_USED 1
+#define THREAD_GSCOPE_FLAG_WAIT 2
+#define THREAD_GSCOPE_RESET_FLAG() \
+  do \
+    { \
+      int __res = atomic_exchange_rel (&THREAD_SELF->header.gscope_flag, \
+				       THREAD_GSCOPE_FLAG_UNUSED); \
+      if (__res == THREAD_GSCOPE_FLAG_WAIT) \
+	lll_futex_wake (&THREAD_SELF->header.gscope_flag, 1, LLL_PRIVATE); \
+    } \
+  while (0)
+#define THREAD_GSCOPE_SET_FLAG() \
+  do \
+    { \
+      THREAD_SELF->header.gscope_flag = THREAD_GSCOPE_FLAG_USED; \
+      atomic_write_barrier (); \
+    } \
+  while (0)
+
+#endif /* __ASSEMBLER__ */
+
+#endif /* tls.h */
diff --git a/sysdeps/loongarch/stackinfo.h b/sysdeps/loongarch/stackinfo.h
new file mode 100644
index 0000000000..a990a471f4
--- /dev/null
+++ b/sysdeps/loongarch/stackinfo.h
@@ -0,0 +1,33 @@ 
+/* Stack environment definitions for LoongArch.
+   Copyright (C) 2021 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, see
+   <https://www.gnu.org/licenses/>.  */
+
+/* This file contains a bit of information about the stack allocation
+   of the processor.  */
+
+#ifndef _STACKINFO_H
+#define _STACKINFO_H 1
+
+#include <elf.h>
+
+/* On LoongArch the stack grows down.  */
+#define _STACK_GROWS_DOWN 1
+
+/* Default to a non-executable stack.  */
+#define DEFAULT_STACK_PERMS (PF_R | PF_W)
+
+#endif /* stackinfo.h */