rtl.h (REG_EH_REGION): Update comment to indicate a value of -1 indicates no throw...

rtl.h (REG_EH_REGION): Update comment to indicate a value of -1 indicates no throw and no nonlocal gotos.

Tue Apr 27 19:50:25 EDT 1999  Andrew MacLeod  <amacleod@cygnus.com>
	* rtl.h (REG_EH_REGION): Update comment to indicate a value of -1
	indicates no throw and no nonlocal gotos.
	* optabs.c (emit_libcall_block): Emit REG_EH_REGION with a value
	of -1 instead of 0 to indicate a nonlocal goto won't happen either.
	* flow.c (count_basic_blocks, find_basic_blocks_1): Ignore libcall
	blocks, look for REG_EH_REGION note exclusively.
	(make_edges): Check for REG_EH_REGION > 0 for specified handlers.

From-SVN: r26680