sparc.c

   1 /********************************************************************
   2  Flush register windows on sparc.
   3
   4  This function is in a separate file to prevent inlining. The "flushw"
   5  assembler instruction used on sparcv9 flushes all register windows
   6  except the current one, so if it is inlined, the current register
   7  window of the process executing the instruction will not be flushed
   8  correctly.
   9
  10  See https://bugs.ruby-lang.org/issues/5244 for discussion.
  11 *********************************************************************/
  12 void
  13 rb_sparc_flush_register_windows(void)
  14 {
  15 /*
  16  * gcc doesn't provide "asm" keyword if -ansi and the various -std options
  17  * are given.
  18  * https://gcc.gnu.org/onlinedocs/gcc/Alternate-Keywords.html
  19  */
  20 #ifndef __GNUC__
  21 #define __asm__ asm
  22 #endif
  23
  24     __asm__
  25 #ifdef __GNUC__
  26     __volatile__
  27 #endif
  28
  29 /* This condition should be in sync with one in configure.ac */
  30 #if defined(__sparcv9) || defined(__sparc_v9__) || defined(__arch64__)
  31 # ifdef __GNUC__
  32     ("flushw" : : : "%o7")
  33 # else
  34     ("flushw")
  35 # endif /* __GNUC__ */
  36 #else
  37     ("ta 0x03")
  38 #endif
  39     ;
  40 }