Re: Stage1 of current CVS gcc aborts when compiling reload1.c

[Richard Henderson <rth at cygnus dot com>]

On Wed, May 17, 2000 at 08:17:39PM +0200, Jan Hubicka wrote:
> > Any update on that? I ask because current CVS still fails when configured
> > for k6-* at the exact same location.
>
> I've investigated a bug a bit and have proper fix for it in my local sources,
> but it depends on some of my other patches to loop.c not reviewed yet.
> I will probably need to make independent fix, but I will probably not
> able to do that before 10th, since I am leaving to Spain soon.

Here's a nice small independant patch for this problem.

Bootstrapped with BOOT_CFLAGS='-O2 -g -march=k6'.


r~

	* rtlanal.c (insn_dependant_p, insn_dependant_p_1): New.
	* rtl.h (insn_dependant_p): Declare it.
	* loop.c (strength_reduce): Use it.

Index: loop.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/loop.c,v
retrieving revision 1.247
diff -c -p -d -r1.247 loop.c
*** loop.c	2000/05/15 17:07:13	1.247
--- loop.c	2000/05/19 03:41:10
*************** strength_reduce (loop, insn_count, flags
*** 4119,4128 ****
  
  		  for (next = NEXT_INSN (dominator); ; next = NEXT_INSN (next))
  		    {
! 		      if ((INSN_P (next)
! 			   && (reg_mentioned_p (giv, PATTERN (next))
! 			       || reg_set_p (bl2->biv->src_reg, next)))
! 			  || GET_CODE (next) == JUMP_INSN)
  			break;
  #ifdef HAVE_cc0
  		      if (! INSN_P (next)
--- 4119,4127 ----
  
  		  for (next = NEXT_INSN (dominator); ; next = NEXT_INSN (next))
  		    {
! 		      if (GET_CODE (next) == JUMP_INSN
! 			  || (INSN_P (next)
! 			      && insn_dependant_p (giv_insn, next)))
  			break;
  #ifdef HAVE_cc0
  		      if (! INSN_P (next)
Index: rtl.h
===================================================================
RCS file: /cvs/gcc/egcs/gcc/rtl.h,v
retrieving revision 1.201
diff -c -p -d -r1.201 rtl.h
*** rtl.h	2000/05/15 19:53:07	1.201
--- rtl.h	2000/05/19 03:41:10
*************** extern int modified_between_p		PARAMS ((
*** 1212,1217 ****
--- 1212,1218 ----
  extern int no_labels_between_p		PARAMS ((rtx, rtx));
  extern int no_jumps_between_p		PARAMS ((rtx, rtx));
  extern int modified_in_p		PARAMS ((rtx, rtx));
+ extern int insn_dependant_p		PARAMS ((rtx, rtx));
  extern int reg_set_p			PARAMS ((rtx, rtx));
  extern rtx single_set			PARAMS ((rtx));
  extern int multiple_sets		PARAMS ((rtx));
Index: rtlanal.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/rtlanal.c,v
retrieving revision 1.61
diff -c -p -d -r1.61 rtlanal.c
*** rtlanal.c	2000/05/09 04:58:44	1.61
--- rtlanal.c	2000/05/19 03:41:10
*************** Boston, MA 02111-1307, USA.  */
*** 26,31 ****
--- 26,32 ----
  
  static int rtx_addr_can_trap_p	PARAMS ((rtx));
  static void reg_set_p_1		PARAMS ((rtx, rtx, void *));
+ static void insn_dependant_p_1	PARAMS ((rtx, rtx, void *));
  static void reg_set_last_1	PARAMS ((rtx, rtx, void *));
  
  
*************** modified_in_p (x, insn)
*** 686,691 ****
--- 687,731 ----
      }
  
    return 0;
+ }
+ 
+ /* Return true if anything in insn X is (anti,output,true) dependant on
+    anything in insn Y.  */
+ 
+ int
+ insn_dependant_p (x, y)
+      rtx x, y;
+ {
+   rtx tmp;
+ 
+   if (! INSN_P (x) || ! INSN_P (y))
+     abort ();
+ 
+   tmp = PATTERN (y);
+   note_stores (PATTERN (x), insn_dependant_p_1, &tmp);
+   if (tmp == NULL_RTX)
+     return 1;
+ 
+   tmp = PATTERN (x);
+   note_stores (PATTERN (y), insn_dependant_p_1, &tmp);
+   if (tmp == NULL_RTX)
+     return 1;
+ 
+   return 0;
+ }
+ 
+ /* A helper routine for insn_dependant_p called through note_stores.  */
+ 
+ static void
+ insn_dependant_p_1 (x, pat, data)
+      rtx x;
+      rtx pat ATTRIBUTE_UNUSED;
+      void *data;
+ {
+   rtx * pinsn = (rtx *) data;
+ 
+   if (*pinsn && reg_mentioned_p (x, *pinsn))
+     *pinsn = NULL_RTX;
  }
  
  /* Given an INSN, return a SET expression if this insn has only a single SET.