tree-vect-data-refs.c (vect_analyze_data_ref_dependences): Assert compute_all_dependences succeeds.

2018-06-29  Richard Biener  <rguenther@suse.de>

	* tree-vect-data-refs.c (vect_analyze_data_ref_dependences): Assert
	compute_all_dependences succeeds.
	* tree-vect-loop.c (vect_get_datarefs_in_loop): Fail early if we
	exceed --param loop-max-datarefs-for-datadeps.

From-SVN: r262244

gcc/ChangeLog

+2018-06-29  Richard Biener  <rguenther@suse.de>
+
+	* tree-vect-data-refs.c (vect_analyze_data_ref_dependences): Assert
+	compute_all_dependences succeeds.
+	* tree-vect-loop.c (vect_get_datarefs_in_loop): Fail early if we
+	exceed --param loop-max-datarefs-for-datadeps.
+
 2018-06-29  Jakub Jelinek  <jakub@redhat.com>
 
 	* config/rs6000/t-rs6000: Append rs6000-modes.h to TM_H.

gcc/tree-vect-data-refs.c

@@ -575,10 +575,11 @@ vect_analyze_data_ref_dependences (loop_vec_info loop_vinfo,
 		 * LOOP_VINFO_DATAREFS (loop_vinfo).length ());
       /* We need read-read dependences to compute
 	 STMT_VINFO_SAME_ALIGN_REFS.  */
-      if (!compute_all_dependences (LOOP_VINFO_DATAREFS (loop_vinfo),
-				    &LOOP_VINFO_DDRS (loop_vinfo),
-				    LOOP_VINFO_LOOP_NEST (loop_vinfo), true))
-	return false;
+      bool res = compute_all_dependences (LOOP_VINFO_DATAREFS (loop_vinfo),
+					  &LOOP_VINFO_DDRS (loop_vinfo),
+					  LOOP_VINFO_LOOP_NEST (loop_vinfo),
+					  true);
+      gcc_assert (res);
     }
 
   LOOP_VINFO_NO_DATA_DEPENDENCIES (loop_vinfo) = true;

gcc/tree-vect-loop.c

@@ -1812,6 +1812,11 @@ vect_get_datarefs_in_loop (loop_p loop, basic_block *bbs,
 	      }
 	    return false;
 	  }
+	/* If dependence analysis will give up due to the limit on the
+	   number of datarefs stop here and fail fatally.  */
+	if (datarefs->length ()
+	    > (unsigned)PARAM_VALUE (PARAM_LOOP_MAX_DATAREFS_FOR_DATADEPS))
+	  return false;
       }
   return true;
 }