src/runtime/x86-arch.h

   1 /* FIXME: Aren't preprocessor symbols with underscore prefixes
   2  * reserved for the system libraries? If so, it would be tidy to
   3  * rename flags like _X86_ARCH_H so their names are in a part of the
   4  * namespace that we control. */
   5 #ifndef _X86_ARCH_H
   6 #define _X86_ARCH_H
   7
   8 #ifndef SBCL_GENESIS_CONFIG
   9 #error genesis/config.h (or sbcl.h) must be included before this file
  10 #endif
  11
  12 #include "interr.h"                     /* for declaration of lose() */
  13
  14 #define ARCH_HAS_STACK_POINTER
  15 #define ALIEN_STACK_GROWS_DOWNWARD
  16
  17 /* FIXME: Do we also want
  18  *   #define ARCH_HAS_FLOAT_REGISTERS
  19  * here? (The answer wasn't obvious to me when merging the
  20  * architecture-abstracting patches for CSR's SPARC port. -- WHN 2002-02-15) */
  21
  22 #define COMPILER_BARRIER \
  23     do { __asm__ __volatile__ ( "" : : : "memory"); } while (0)
  24
  25 #ifdef LISP_FEATURE_WIN32
  26 extern int os_number_of_processors;
  27 #define yield_on_uniprocessor()                 \
  28     do { if (os_number_of_processors<=1) SwitchToThread(); } while(0)
  29 #else
  30 /* Stubs are better than ifdef EVERYWHERE. */
  31 #define yield_on_uniprocessor()                 \
  32     do {} while(0)
  33 #endif
  34
  35
  36 static inline void
  37 get_spinlock(volatile lispobj *word, unsigned long value)
  38 {
  39 #ifdef LISP_FEATURE_SB_THREAD
  40     u32 eax=0;
  41     if(*word==value)
  42         lose("recursive get_spinlock: 0x%x,%ld\n",word,value);
  43     do {
  44 #if defined(LISP_FEATURE_DARWIN)
  45         asm volatile ("xor %0,%0;\n\
  46               lock/cmpxchg %1,%2"
  47              : "=a" (eax)
  48              : "r" (value), "m" (*word)
  49              : "memory", "cc");
  50 #else
  51         if (eax!=0) {
  52             asm volatile("rep; nop");
  53         }
  54         asm volatile ("xor %0,%0\n\
  55               lock cmpxchg %1,%2"
  56              : "=a" (eax)
  57              : "r" (value), "m" (*word)
  58              : "memory", "cc");
  59 #endif
  60         yield_on_uniprocessor();
  61     } while(eax!=0);
  62 #else
  63     *word=value;
  64 #endif
  65 }
  66
  67 static inline void
  68 release_spinlock(volatile lispobj *word)
  69 {
  70     /* See comment in RELEASE-SPINLOCK in target-thread.lisp. */
  71     COMPILER_BARRIER;
  72     *word=0;
  73     COMPILER_BARRIER;
  74 }
  75
  76 static inline lispobj
  77 swap_lispobjs(volatile lispobj *dest, lispobj value)
  78 {
  79     lispobj old_value;
  80 #if defined(LISP_FEATURE_DARWIN)
  81     asm volatile ("lock/xchg %0,(%1)"
  82          : "=r" (old_value)
  83          : "r" (dest), "0" (value)
  84          : "memory");
  85 #else
  86     asm volatile ("lock xchg %0,(%1)"
  87          : "=r" (old_value)
  88          : "r" (dest), "0" (value)
  89          : "memory");
  90 #endif
  91     return old_value;
  92 }
  93
  94 extern void fast_bzero_detect(void *, size_t);
  95 extern void (*fast_bzero_pointer)(void *, size_t);
  96
  97 #endif /* _X86_ARCH_H */