gensupport: Fix define_subst operand renumbering.

When processing substitutions the operands are renumbered.  To find a
free operand number the array used_operands_numbers is used.
Currently this array is used to assign new numbers before all the
RTXes in the vector have been processed.  I did run into problems with
this for insns where a match_dup occurred in a later (use ...) operand
referring to an earlier operand (e.g. s390.md "setmem_long").

The patch splits the loop doing the processing into two in order to
have all the operand numbers collected already when assigning new
numbers.

gcc/ChangeLog:

2016-03-01  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* gensupport.c (process_substs_on_one_elem): Split loop to
	complete mark_operands_used_in_match_dup on all expressions in the
	vector first.
	(adjust_operands_numbers): Inline into process_substs_on_one_elem
	and remove function.

From-SVN: r233841

2 files changed, 28 insertions, 25 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1461a95..b1bdd0d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2016-03-01  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
+	* gensupport.c (process_substs_on_one_elem): Split loop to
+	complete mark_operands_used_in_match_dup on all expressions in the
+	vector first.
+	(adjust_operands_numbers): Inline into process_substs_on_one_elem
+	and remove function.
+
 2016-02-29  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR target/69706
diff --git a/gcc/gensupport.c b/gcc/gensupport.c
index 8c5a1ab..de29579 100644
--- a/gcc/gensupport.c
+++ b/gcc/gensupport.c
@@ -126,7 +126,10 @@ static const char * duplicate_each_alternative (const char * str, int n_dup);
 
 typedef const char * (*constraints_handler_t) (const char *, int);
 static rtx alter_constraints (rtx, int, constraints_handler_t);
-static rtx adjust_operands_numbers (rtx);
+
+static void mark_operands_used_in_match_dup (rtx);
+static void renumerate_operands_in_pattern (rtx);
+
 static rtx replace_duplicating_operands_in_pattern (rtx);
 
 /* Make a version of gen_rtx_CONST_INT so that GEN_INT can be used in
@@ -1844,7 +1847,18 @@ process_substs_on_one_elem (struct queue_elem *elem,
 	  subst_pattern = alter_constraints (subst_pattern, alternatives,
 					     duplicate_each_alternative);
 
-	  subst_pattern = adjust_operands_numbers (subst_pattern);
+	  mark_operands_used_in_match_dup (subst_pattern);
+	  RTVEC_ELT (subst_pattern_vec, j) = subst_pattern;
+	}
+
+      for (j = 0; j < XVECLEN (subst_elem->data, 3); j++)
+	{
+	  subst_pattern = RTVEC_ELT (subst_pattern_vec, j);
+
+	  /* The number of MATCH_OPERANDs in the output pattern might
+	     change.  This routine assigns new numbers to the
+	     MATCH_OPERAND expressions to avoid collisions.  */
+	  renumerate_operands_in_pattern (subst_pattern);
 
 	  /* Substitute match_dup and match_op_dup in the new pattern and
 	     duplicate constraints.  */
@@ -1857,7 +1871,6 @@ process_substs_on_one_elem (struct queue_elem *elem,
 	  if (GET_CODE (elem->data) == DEFINE_EXPAND)
 	    remove_constraints (subst_pattern);
 
-	  RTVEC_ELT (subst_pattern_vec, j) = subst_pattern;
 	}
       XVEC (elem->data, 1) = subst_pattern_vec;
 
@@ -1927,7 +1940,7 @@ mark_operands_from_match_dup (rtx pattern)
     }
 }
 
-/* This is a subroutine of adjust_operands_numbers.
+/* This is a subroutine of process_substs_on_one_elem.
    It goes through all expressions in PATTERN and when MATCH_DUP is
    met, all MATCH_OPERANDs inside it is marked as occupied.  The
    process of marking is done by routin mark_operands_from_match_dup.  */
@@ -1973,10 +1986,9 @@ find_first_unused_number_of_operand ()
   return MAX_OPERANDS;
 }
 
-/* This is subroutine of adjust_operands_numbers.
-   It visits all expressions in PATTERN and assigns not-occupied
-   operand indexes to MATCH_OPERANDs and MATCH_OPERATORs of this
-   PATTERN.  */
+/* This is a subroutine of process_substs_on_one_elem.  It visits all
+   expressions in PATTERN and assigns not-occupied operand indexes to
+   MATCH_OPERANDs and MATCH_OPERATORs of this PATTERN.  */
 static void
 renumerate_operands_in_pattern (rtx pattern)
 {
@@ -2011,23 +2023,6 @@ renumerate_operands_in_pattern (rtx pattern)
     }
 }
 
-/* If output pattern of define_subst contains MATCH_DUP, then this
-   expression would be replaced with the pattern, matched with
-   MATCH_OPERAND from input pattern.  This pattern could contain any
-   number of MATCH_OPERANDs, MATCH_OPERATORs etc., so it's possible
-   that a MATCH_OPERAND from output_pattern (if any) would have the
-   same number, as MATCH_OPERAND from copied pattern.  To avoid such
-   indexes overlapping, we assign new indexes to MATCH_OPERANDs,
-   laying in the output pattern outside of MATCH_DUPs.  */
-static rtx
-adjust_operands_numbers (rtx pattern)
-{
-  mark_operands_used_in_match_dup (pattern);
-
-  renumerate_operands_in_pattern (pattern);
-
-  return pattern;
-}
 
 /* Generate RTL expression
    (match_dup OPNO)