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[patch] h8300.md: Tweak comments.


Hi,

The comment in the first hunk is wrong.  We have a lot more profitable
cases where we can merge a stack adjustment and stores into the stack.

The rest of the patch simply adds comments.

Committed.

Kazu Hirata

2004-02-10  Kazu Hirata  <kazu@cs.umass.edu>

	* config/h8300/h8300.md: Remove an incorrect comment about
	peephole2.  Add comments.

Index: h8300.md
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/h8300/h8300.md,v
retrieving revision 1.261
diff -c -r1.261 h8300.md
*** h8300.md	1 Feb 2004 17:01:34 -0000	1.261
--- h8300.md	10 Feb 2004 22:35:41 -0000
***************
*** 4971,4979 ****
     operands[7] = gen_int_mode (INTVAL (operands[2]), QImode);")
  
  ;; These triggers right at the end of allocation of locals in the
! ;; prologue.  The only profitable cases are when we have stack
! ;; adjustment of -4 or -12.  That of -8 won't happen because it is
! ;; always split into two consecutive subtractions of -4.
  
  (define_peephole2
    [(set (reg:SI SP_REG)
--- 4971,4982 ----
     operands[7] = gen_int_mode (INTVAL (operands[2]), QImode);")
  
  ;; These triggers right at the end of allocation of locals in the
! ;; prologue (and possibly at other places).
! 
! ;; stack adjustment of -8, generate one push
! ;;
! ;; before : 14 bytes, 22 clocks
! ;; after  :  8 bytes, 20 clocks
  
  (define_peephole2
    [(set (reg:SI SP_REG)
***************
*** 4986,4991 ****
--- 4989,4999 ----
    [(set (mem:SI (pre_dec:SI (reg:SI SP_REG)))
  	(match_dup 0))]
    "")
+ 
+ ;; stack adjustment of -12, generate one push
+ ;;
+ ;; before : 10 bytes, 14 clocks
+ ;; after  :  8 bytes, 14 clocks
  
  (define_peephole2
    [(set (reg:SI SP_REG)


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