patch to omit the frame pointer from leaf functions

[John Wehle]

This change allows gcc to omit the frame pointer when optimizing
leaf functions which don't call alloca.  Are the situations where
having a frame pointer in a leaf function is a win (assuming that
the machine description doesn't require it)?

Notes:

  1) The earlier patch which improves the accuracy of function_call_count
     should be installed prior to this.

ChangeLog:

Mon Sep 21 01:38:35 EDT 1998  John Wehle  (john@feith.com)

	* reload1.c (reload): Don't set frame_pointer_needed when
	optimizing leaf functions.

Enjoy!

-- John Wehle
------------------8<------------------------8<------------------------
*** gcc/reload1.c.ORIGINAL	Thu Sep 17 22:59:26 1998
--- gcc/reload1.c	Mon Sep 21 01:33:32 1998
*************** reload (first, global, dumpfile)
*** 750,756 ****
  
    /* Does this function require a frame pointer?  */
  
!   frame_pointer_needed = (! flag_omit_frame_pointer
  #ifdef EXIT_IGNORE_STACK
  			  /* ?? If EXIT_IGNORE_STACK is set, we will not save
  			     and restore sp for alloca.  So we can't eliminate
--- 750,758 ----
  
    /* Does this function require a frame pointer?  */
  
!   frame_pointer_needed = ((! flag_omit_frame_pointer
! 			     && (! optimize || function_call_count != 0
! 				 || current_function_calls_alloca))
  #ifdef EXIT_IGNORE_STACK
  			  /* ?? If EXIT_IGNORE_STACK is set, we will not save
  			     and restore sp for alloca.  So we can't eliminate
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