Userland part of the TLS implementation for x86.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@2362 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kernel/libroot/os/Jamfile

@@ -11,6 +11,7 @@ KernelMergeObject os_main.o :
 	<$(SOURCE_GRIST)>team.c
 	<$(SOURCE_GRIST)>thread.c
 	<$(SOURCE_GRIST)>time.c
+	<$(SOURCE_GRIST)>tls.c
 	<$(SOURCE_GRIST)>syscalls.S
 	:
 	-fPIC -DPIC

src/kernel/libroot/os/tls.c

@@ -0,0 +1,72 @@
+/* 
+** Copyright 2002, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+** Distributed under the terms of the OpenBeOS License.
+*/
+
+
+// we don't want to have the inline assembly included here
+#ifndef _NO_INLINE_ASM
+#	define _NO_INLINE_ASM 1
+#endif
+
+#include "support/TLS.h"
+
+
+// ToDo: we probably need to set some standard slots (like it's done in BeOS)!
+// 	Slot 1 is obviously the thread ID, but there are 8 pre-allocated slots in BeOS.
+//	I have no idea what the other slots are used for; they are all NULL when the
+//	thread has just started, but slots 0 & 1.
+//	Slot 0 seems to be an address somewhere on the stack. Another slot is most probably
+//	reserved for "errno", the others could have been used to make some POSIX calls
+//	thread-safe - but we also have to find out which supposely non-thread-safe POSIX
+//	calls are thread-safe in BeOS.
+static int32 gNextSlot = 0;
+
+
+int32
+tls_allocate(void)
+{
+	int32 next = atomic_add(&gNextSlot, 1);
+	if (next >= TLS_MAX_KEYS)
+		return B_NO_MEMORY;
+
+	return next;
+}
+
+
+#if __INTEL__ && __GNUC__
+
+void *
+tls_get(int32 index)
+{
+	void *ret;
+	__asm__ __volatile__ ( 
+		"movl	%%fs:(,%%edx, 4), %%eax \n\t"
+		: "=a"(ret) : "d"(index) );
+	return ret;
+}
+
+
+void **
+tls_address(int32 index)
+{
+	void *ret;
+	__asm__ __volatile__ ( 
+		"movl	%%fs:0, %%eax \n\t"
+		"leal	(%%eax, %%edx, 4), %%eax \n\t"
+		: "=a"(ret) : "d"(index) );
+	return ret;
+}
+
+
+void
+tls_set(int32 index, void *value)
+{
+	__asm__ __volatile__ ( 
+		"movl	%%eax, %%fs:(,%%edx, 4) \n\t"
+		: : "d"(index), "a"(value) );
+}
+
+#else
+#	error "TLS has not been implemented for this platform"
+#endif