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-rw-r--r--libpthread/linuxthreads/sysdeps/mips/tls.h169
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diff --git a/libpthread/linuxthreads/sysdeps/mips/tls.h b/libpthread/linuxthreads/sysdeps/mips/tls.h
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+++ b/libpthread/linuxthreads/sysdeps/mips/tls.h
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+/* Definitions for thread-local data handling. linuxthreads/MIPS version.
+ Copyright (C) 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, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _TLS_H
+#define _TLS_H
+
+#ifndef __ASSEMBLER__
+
+# include <stdbool.h>
+# include <pt-machine.h>
+# include <stddef.h>
+
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ struct
+ {
+ void *val;
+ bool is_static;
+ } pointer;
+} dtv_t;
+
+# define READ_THREAD_POINTER() \
+ ({ void *__result; \
+ __asm__ __volatile__ (".set\tpush\n\t.set\tmips32r2\n\t" \
+ "rdhwr\t%0, $29\n\t.set\tpop" : "=v" (__result)); \
+ __result; })
+
+#else /* __ASSEMBLER__ */
+# include <tcb-offsets.h>
+
+/* Note: rd must be $v1 to be ABI-conformant. */
+# define READ_THREAD_POINTER(rd) \
+ .set push; \
+ .set mips32r2; \
+ rdhwr rd, $29; \
+ .set pop
+#endif /* __ASSEMBLER__ */
+
+/* LinuxThreads can only use TLS if both floating stacks (in the MIPS case,
+ that means support for "rdhwr") and support from the tools are available.
+
+ We have to define USE_TLS consistently, or ldsodefs.h will lay out types
+ differently between an NPTL build and a LinuxThreads build. It can be set
+ for libc.so and not libpthread.so, but only if we provide appropriate padding
+ in the _pthread_descr_struct.
+
+ Currently nothing defines FLOATING_STACKS. We could assume this based on
+ kernel version once the TLS patches are available in kernel.org, but
+ it hardly seems worth it. Use NPTL if you can.
+
+ To avoid bothering with the TLS support code at all, use configure
+ --without-tls. */
+
+#if defined HAVE_TLS_SUPPORT \
+ && (defined FLOATING_STACKS || !defined IS_IN_libpthread)
+
+/* Signal that TLS support is available. */
+# define USE_TLS 1
+
+/* Include padding in _pthread_descr_struct so that libc can find p_errno,
+ if libpthread will only include the padding because of the !IS_IN_libpthread
+ check. */
+#ifndef FLOATING_STACKS
+# define INCLUDE_TLS_PADDING 1
+#endif
+
+# ifndef __ASSEMBLER__
+
+/* This layout is actually wholly private and not affected by the ABI.
+ Nor does it overlap the pthread data structure, so we need nothing
+ extra here at all. */
+typedef struct
+{
+ dtv_t *dtv;
+ void *private;
+} tcbhead_t;
+
+/* This is the size of the initial TCB. */
+# define TLS_INIT_TCB_SIZE 0
+
+/* Alignment requirements for the initial TCB. */
+# define TLS_INIT_TCB_ALIGN __alignof__ (struct _pthread_descr_struct)
+
+/* This is the size of the TCB. */
+# define TLS_TCB_SIZE 0
+
+/* Alignment requirements for the TCB. */
+# define TLS_TCB_ALIGN __alignof__ (struct _pthread_descr_struct)
+
+/* This is the size we need before TCB. */
+# define TLS_PRE_TCB_SIZE \
+ (sizeof (struct _pthread_descr_struct) \
+ + ((sizeof (tcbhead_t) + TLS_TCB_ALIGN - 1) & ~(TLS_TCB_ALIGN - 1)))
+
+/* The thread pointer (in hardware register $29) points to the end of
+ the TCB + 0x7000, as for PowerPC. The pthread_descr structure is
+ immediately in front of the TCB. */
+#define TLS_TCB_OFFSET 0x7000
+
+/* The DTV is allocated at the TP; the TCB is placed elsewhere. */
+/* This is not really true for powerpc64. We are following alpha
+ where the DTV pointer is first doubleword in the TCB. */
+# define TLS_DTV_AT_TP 1
+
+/* 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. 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(tcbp, secondcall) \
+ ({ INTERNAL_SYSCALL_DECL (err); \
+ long result_var; \
+ result_var = INTERNAL_SYSCALL (set_thread_area, err, 1, \
+ (char *) (tcbp) + TLS_TCB_OFFSET); \
+ INTERNAL_SYSCALL_ERROR_P (result_var, err) \
+ ? "unknown error" : 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. */
+# undef THREAD_SELF
+# define THREAD_SELF \
+ ((pthread_descr) (READ_THREAD_POINTER () \
+ - TLS_TCB_OFFSET - TLS_PRE_TCB_SIZE))
+
+/* Get the thread descriptor definition. */
+# include <linuxthreads/descr.h>
+
+/* l_tls_offset == 0 is perfectly valid on MIPS, so we have to use some
+ different value to mean unset l_tls_offset. */
+# define NO_TLS_OFFSET -1
+
+/* Initializing the thread pointer requires a syscall which may not be
+ available, so don't do it if we don't need to. */
+# define TLS_INIT_TP_EXPENSIVE 1
+
+# endif /* __ASSEMBLER__ */
+
+#endif /* HAVE_TLS_SUPPORT */
+
+#endif /* tls.h */