> 2005-06-02 Steven Bosscher <stevenb@suse.de> > Mostafa Hagog...

> 2005-06-02 Steven Bosscher  <stevenb@suse.de>
>            Mostafa Hagog <mustafa@il.ibm.com>
>
>       * cfgloop.h (doloop_condition_get): Make external.
>       * loop-doloop.c (doloop_condition_get): Generalize to make it
>       usable in modulo-sched.c.
>       * modulo-sched.c (doloop_register_get): Use
>       doloop_condition_get instead of duplicating it.

Co-Authored-By: Mostafa Hagog <mustafa@il.ibm.com>

From-SVN: r100490

gcc/ChangeLog

+2005-06-02 Steven Bosscher  <stevenb@suse.de>
+	   Mostafa Hagog <mustafa@il.ibm.com>
+
+	* cfgloop.h (doloop_condition_get): Make external.
+	* loop-doloop.c (doloop_condition_get): Generalize to make it
+	usable in modulo-sched.c.
+	* modulo-sched.c (doloop_register_get): Use
+	doloop_condition_get instead of duplicating it.
+
 2005-06-02  Bernd Schmidt  <bernd.schmidt@analog.com>
 
 	* reload1.c (reload): Undo 2005-04-20 change.  Make sure we detect

gcc/cfgloop.h

@@ -289,6 +289,7 @@ extern void verify_loop_structure (struct loops *);
 /* Loop analysis.  */
 extern bool just_once_each_iteration_p (const struct loop *, basic_block);
 extern unsigned expected_loop_iterations (const struct loop *);
+extern rtx doloop_condition_get (rtx);
 
 /* Loop manipulation.  */
 extern bool can_duplicate_loop_p (struct loop *loop);

gcc/loop-doloop.c

@@ -69,12 +69,13 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 /* Return the loop termination condition for PATTERN or zero
    if it is not a decrement and branch jump insn.  */
 
-static rtx
+rtx
 doloop_condition_get (rtx pattern)
 {
   rtx cmp;
   rtx inc;
   rtx reg;
+  rtx inc_src;
   rtx condition;
 
   /* The canonical doloop pattern we expect is:
@@ -85,12 +86,13 @@ doloop_condition_get (rtx pattern)
                 (set (reg) (plus (reg) (const_int -1)))
                 (additional clobbers and uses)])
 
-     Some machines (IA-64) make the decrement conditional on
-     the condition as well, so we don't bother verifying the
-     actual decrement.  In summary, the branch must be the
-     first entry of the parallel (also required by jump.c),
-     and the second entry of the parallel must be a set of
-     the loop counter register.  */
+     Some targets (IA-64) wrap the set of the loop counter in
+     an if_then_else too.
+
+     In summary, the branch must be the first entry of the
+     parallel (also required by jump.c), and the second
+     entry of the parallel must be a set of the loop counter
+     register.  */
 
   if (GET_CODE (pattern) != PARALLEL)
     return 0;
@@ -99,11 +101,21 @@ doloop_condition_get (rtx pattern)
   inc = XVECEXP (pattern, 0, 1);
 
   /* Check for (set (reg) (something)).  */
-  if (GET_CODE (inc) != SET || ! REG_P (SET_DEST (inc)))
+  if (GET_CODE (inc) != SET)
     return 0;
-
-  /* Extract loop counter register.  */
   reg = SET_DEST (inc);
+  if (! REG_P (reg))
+    return 0;
+
+  /* Check if something = (plus (reg) (const_int -1)).
+     On IA-64, this decrement is wrapped in an if_then_else.  */
+  inc_src = SET_SRC (inc);
+  if (GET_CODE (inc_src) == IF_THEN_ELSE)
+    inc_src = XEXP (inc_src, 1);
+  if (GET_CODE (inc_src) != PLUS
+      || XEXP (inc_src, 0) != reg
+      || XEXP (inc_src, 1) != constm1_rtx)
+    return 0;
 
   /* Check for (set (pc) (if_then_else (condition)
                                        (label_ref (label))
@@ -118,15 +130,16 @@ doloop_condition_get (rtx pattern)
   /* Extract loop termination condition.  */
   condition = XEXP (SET_SRC (cmp), 0);
 
-  if ((GET_CODE (condition) != GE && GET_CODE (condition) != NE)
-      || GET_CODE (XEXP (condition, 1)) != CONST_INT)
+  /* We expect a GE or NE comparison with 0 or 1.  */
+  if ((GET_CODE (condition) != GE
+       && GET_CODE (condition) != NE)
+      || (XEXP (condition, 1) != const0_rtx
+          && XEXP (condition, 1) != const1_rtx))
     return 0;
 
-  if (XEXP (condition, 0) == reg)
-    return condition;
-
-  if (GET_CODE (XEXP (condition, 0)) == PLUS
-      && XEXP (XEXP (condition, 0), 0) == reg)
+  if ((XEXP (condition, 0) == reg)
+      || (GET_CODE (XEXP (condition, 0)) == PLUS
+		   && XEXP (XEXP (condition, 0), 0) == reg))
     return condition;
 
   /* ??? If a machine uses a funny comparison, we could return a

gcc/modulo-sched.c

@@ -269,74 +269,31 @@ static struct sched_info sms_sched_info =
 };
 
 
-/* Return the register decremented and tested or zero if it is not a decrement
-   and branch jump insn (similar to doloop_condition_get).  */
+/* Return the register decremented and tested in INSN,
+   or zero if it is not a decrement-and-branch insn.  */
+
 static rtx
-doloop_register_get (rtx insn, rtx *comp)
+doloop_register_get (rtx insn)
 {
-  rtx pattern, cmp, inc, reg, condition;
-
-  if (!JUMP_P (insn))
-    return NULL_RTX;
-  pattern = PATTERN (insn);
-
-  /* The canonical doloop pattern we expect is:
-
-     (parallel [(set (pc) (if_then_else (condition)
-					(label_ref (label))
-					(pc)))
-		(set (reg) (plus (reg) (const_int -1)))
-		(additional clobbers and uses)])
-
-    where condition is further restricted to be
-      (ne (reg) (const_int 1)).  */
-
-  if (GET_CODE (pattern) != PARALLEL)
-    return NULL_RTX;
-
-  cmp = XVECEXP (pattern, 0, 0);
-  inc = XVECEXP (pattern, 0, 1);
-  /* Return the compare rtx.  */
-  *comp = cmp;
+  rtx pattern, reg, condition;
 
-  /* Check for (set (reg) (something)).  */
-  if (GET_CODE (inc) != SET || ! REG_P (SET_DEST (inc)))
+  if (! JUMP_P (insn))
     return NULL_RTX;
 
-  /* Extract loop counter register.  */
-  reg = SET_DEST (inc);
-
-  /* Check if something = (plus (reg) (const_int -1)).  */
-  if (GET_CODE (SET_SRC (inc)) != PLUS
-      || XEXP (SET_SRC (inc), 0) != reg
-      || XEXP (SET_SRC (inc), 1) != constm1_rtx)
-    return NULL_RTX;
-
-  /* Check for (set (pc) (if_then_else (condition)
-				       (label_ref (label))
-				       (pc))).  */
-  if (GET_CODE (cmp) != SET
-      || SET_DEST (cmp) != pc_rtx
-      || GET_CODE (SET_SRC (cmp)) != IF_THEN_ELSE
-      || GET_CODE (XEXP (SET_SRC (cmp), 1)) != LABEL_REF
-      || XEXP (SET_SRC (cmp), 2) != pc_rtx)
-    return NULL_RTX;
-
-  /* Extract loop termination condition.  */
-  condition = XEXP (SET_SRC (cmp), 0);
-
-  /* Check if condition = (ne (reg) (const_int 1)), which is more
-     restrictive than the check in doloop_condition_get:
-     if ((GET_CODE (condition) != GE && GET_CODE (condition) != NE)
-	 || GET_CODE (XEXP (condition, 1)) != CONST_INT).  */
-  if (GET_CODE (condition) != NE
-      || XEXP (condition, 1) != const1_rtx)
+  pattern = PATTERN (insn);
+  condition = doloop_condition_get (pattern);
+  if (! condition)
     return NULL_RTX;
 
-  if (XEXP (condition, 0) == reg)
-    return reg;
+  if (REG_P (XEXP (condition, 0)))
+    reg = XEXP (condition, 0);
+  else if (GET_CODE (XEXP (condition, 0)) == PLUS
+	   && REG_P (XEXP (XEXP (condition, 0), 0)))
+    reg = XEXP (XEXP (condition, 0), 0);
+  else
+    gcc_unreachable ();
 
-  return NULL_RTX;
+  return reg;
 }
 
 /* Check if COUNT_REG is set to a constant in the PRE_HEADER block, so
@@ -1025,7 +982,7 @@ sms_schedule (FILE *dump_file)
   for (i = 0; i < loops->num; i++)
     {
       rtx head, tail;
-      rtx count_reg, comp;
+      rtx count_reg;
       struct loop *loop = loops->parray[i];
 
       /* For debugging.  */
@@ -1088,7 +1045,7 @@ sms_schedule (FILE *dump_file)
         }
 
       /* Make sure this is a doloop.  */
-      if ( !(count_reg = doloop_register_get (tail, &comp)))
+      if ( !(count_reg = doloop_register_get (tail)))
 	continue;
 
       /* Don't handle BBs with calls or barriers, or !single_set insns.  */
@@ -1134,7 +1091,7 @@ sms_schedule (FILE *dump_file)
   for (i = 0; i < num_loops; i++)
     {
       rtx head, tail;
-      rtx count_reg, count_init, comp;
+      rtx count_reg, count_init;
       int mii, rec_mii;
       unsigned stage_count = 0;
       HOST_WIDEST_INT loop_count = 0;
@@ -1186,7 +1143,7 @@ sms_schedule (FILE *dump_file)
       /* In case of th loop have doloop register it gets special
 	 handling.  */
       count_init = NULL_RTX;
-      if ((count_reg = doloop_register_get (tail, &comp)))
+      if ((count_reg = doloop_register_get (tail)))
 	{
 	  basic_block pre_header;