-/* -----------------------------------------------------------------------------
- The gct variable is thread-local and points to the current thread's
- gc_thread structure. It is heavily accessed, so we try to put gct
- into a global register variable if possible; if we don't have a
- register then use gcc's __thread extension to create a thread-local
- variable.
-
- Even on x86 where registers are scarce, it is worthwhile using a
- register variable here: I measured about a 2-5% slowdown with the
- __thread version.
- -------------------------------------------------------------------------- */
-
-#define GLOBAL_REG_DECL(type,name,reg) register type name REG(reg);
-
-#if defined(sparc_HOST_ARCH)
-// Don't use REG_base or R1 for gct on SPARC because they're getting clobbered
-// by something else. Not sure what yet. -- BL 2009/01/03
-
-extern __thread gc_thread* gct;
-#define DECLARE_GCT __thread gc_thread* gct;
-
-#elif defined(REG_Base) && !defined(i386_HOST_ARCH)
-// on i386, REG_Base is %ebx which is also used for PIC, so we don't
-// want to steal it
-
-GLOBAL_REG_DECL(gc_thread*, gct, REG_Base)
-#define DECLARE_GCT /* nothing */
-
-#elif defined(REG_R1)
-
-GLOBAL_REG_DECL(gc_thread*, gct, REG_R1)
-#define DECLARE_GCT /* nothing */
-
-#elif defined(__GNUC__)
-
-extern __thread gc_thread* gct;
-#define DECLARE_GCT __thread gc_thread* gct;
-
-#else
-
-#error Cannot find a way to declare the thread-local gct
-
-#endif