headers/os/support/TLS.h

   1 /*
   2  * Copyright 2003-2007 Haiku, Inc. All rights reserved.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef _TLS_H
   6 #define _TLS_H
   7
   8
   9 #include <BeBuild.h>
  10 #include <SupportDefs.h>
  11
  12
  13 /* A maximum of 64 keys is allowed to store in TLS - the key is reserved
  14  * process-wide. Note that tls_allocate() will return B_NO_MEMORY if you
  15  * try to exceed this limit.
  16  */
  17 #define TLS_MAX_KEYS 64
  18
  19
  20 #ifdef __cplusplus
  21 extern "C" {
  22 #endif  /* __cplusplus */
  23
  24 extern int32 tls_allocate(void);
  25
  26 #if !_NO_INLINE_ASM && __INTEL__ && __GNUC__
  27
  28 static inline void *
  29 tls_get(int32 index)
  30 {
  31         void *ret;
  32         __asm__ __volatile__ (
  33                 "movl   %%fs:(, %1, 4), %0"
  34                 : "=r" (ret) : "r" (index));
  35         return ret;
  36 }
  37
  38 static inline void **
  39 tls_address(int32 index)
  40 {
  41         void **ret;
  42         __asm__ __volatile__ (
  43                 "movl   %%fs:0, %0\n\t"
  44                 "leal   (%0, %1, 4), %0\n\t"
  45                 : "=&r" (ret) : "r" (index));
  46         return ret;
  47 }
  48
  49 static inline void
  50 tls_set(int32 index, void *value)
  51 {
  52         __asm__ __volatile__ (
  53                 "movl   %1, %%fs:(, %0, 4)"
  54                 : : "r" (index), "r" (value));
  55 }
  56
  57 #else   /* !_NO_INLINE_ASM && __INTEL__ && __GNUC__ */
  58
  59 extern void *tls_get(int32 index);
  60 extern void **tls_address(int32 index);
  61 extern void tls_set(int32 index, void *value);
  62
  63 #endif  /* !_NO_INLINE_ASM && __INTEL__ && __GNUC__ */
  64
  65 #ifdef __cplusplus
  66 }
  67 #endif  /* __cplusplus */
  68
  69 #endif  /* _TLS_H */