cvs commit: src/sys/i386/i386 machdep.c

[Bruce Evans]

bde         2004-06-19 12:28:48 UTC

  FreeBSD src repository

  Modified files:
    sys/i386/i386        machdep.c 
  Log:
  Removed foot-shooting setting of CR0_TS in exec_setregs().  It is
  unnecessary because cpu_setregs() and/or npxinit() always sets CR0_TS
  during system initialization, and CR0_TS is set in the next statement
  (fpstate_drop()) if necessary after system initialization.  Setting
  it unnecessarily was less than a pessimization since it broke the
  invariant that the npx can be used without an npxdna() trap if
  fpucurthread is non-null.  The broken invariant became harmful when I
  added an fnclex to npxdrop().
  
  Removed setting of CR0_MP in exec_setregs().  This was similarly
  unnecessary but was harmless.
  
  Updated comments (mainly by removing them).  Things are simpler now
  that we have cpu_setregs() and don't support a math emulator or pretend
  to support not having either a math emulator or an npx.
  
  Removed the ifdef for avoiding setting CR0_NE in the !SMP case in
  cpu_setregs().  npx_probe() should reverse the setting if it wants to
  force IRQ13 exception handling for testing.
  
  Revision  Changes    Path
  1.592     +7 -25     src/sys/i386/i386/machdep.c