dwarf2-signal.h (MAKE_THROW_FRAME, sparc32): Document magic instruction reading sequence.

2002-04-21  David S. Miller  <davem@redhat.com>

	* include/dwarf2-signal.h (MAKE_THROW_FRAME, sparc32): Document
	magic instruction reading sequence.

From-SVN: r52609

libjava/ChangeLog

+2002-04-21  David S. Miller  <davem@redhat.com>
+
+	* include/dwarf2-signal.h (MAKE_THROW_FRAME, sparc32): Document
+	magic instruction reading sequence.
+
 2002-04-21  Mark Wielaard  <mark@klomp.org>
 
 	* mauve-libgcj: Don't run java.lang.ref tests since they are buggy.

libjava/include/dwarf2-signal.h

@@ -77,9 +77,11 @@ do									\
   } *regp;								\
   unsigned int insn;							\
   __asm__ __volatile__("ld [%%i7 + 8], %0" : "=r" (insn));		\
+  /* mov __NR_sigaction, %g1; Old signal stack layout */		\
   if (insn == 0x821020d8)						\
     regp = (struct sig_regs *) _sip;					\
   else									\
+    /* mov __NR_rt_sigaction, %g1; New signal stack layout */		\
     regp = (struct sig_regs *) (_sip + 1);				\
   regp->pc = regp->npc;							\
   regp->npc += 4;							\