tree-vect-loop.c (vect_analyze_loop_2): Add fatal parameter.

2015-11-13  Richard Biener  <rguenther@suse.de>

	* tree-vect-loop.c (vect_analyze_loop_2): Add fatal parameter.
	Signal fatal failure if early checks fail.
	(vect_analyze_loop): If vect_analyze_loop_2 fails fatally
	do not bother testing further vector sizes.

From-SVN: r230292

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 666545eba8e3079f1d856d21cda13dd869c839eb..73668fa15db5ebe35c6dc2f53f0d8d817a6194e7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2015-11-13  Richard Biener  <rguenther@suse.de>
+
+       * tree-vect-loop.c (vect_analyze_loop_2): Add fatal parameter.
+       Signal fatal failure if early checks fail.
+       (vect_analyze_loop): If vect_analyze_loop_2 fails fatally
+       do not bother testing further vector sizes.
+
 2015-11-13  Uros Bizjak  <ubizjak@gmail.com>
 
        * config/i386/predicates.md (misaligned_operand): Return true if

diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
index 55e53093caaf663d592dccbf2c913f334f79b3d9..b2fac61185186eaa0b6d742ff8b8ec597482c8d5 100644 (file)
--- a/gcc/tree-vect-loop.c
+++ b/gcc/tree-vect-loop.c
@@ -1709,13 +1709,16 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo)
    for it.  The different analyses will record information in the
    loop_vec_info struct.  */
 static bool
-vect_analyze_loop_2 (loop_vec_info loop_vinfo)
+vect_analyze_loop_2 (loop_vec_info loop_vinfo, bool &fatal)
 {
   bool ok;
   int max_vf = MAX_VECTORIZATION_FACTOR;
   int min_vf = 2;
   unsigned int n_stmts = 0;
 
+  /* The first group of checks is independent of the vector size.  */
+  fatal = true;
+
   /* Find all data references in the loop (which correspond to vdefs/vuses)
      and analyze their evolution in the loop.  */
 
@@ -1795,7 +1798,6 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo)
 
   /* Classify all cross-iteration scalar data-flow cycles.
      Cross-iteration cycles caused by virtual phis are analyzed separately.  */
-
   vect_analyze_scalar_cycles (loop_vinfo);
 
   vect_pattern_recog (loop_vinfo);
@@ -1825,6 +1827,9 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo)
       return false;
     }
 
+  /* While the rest of the analysis below depends on it in some way.  */
+  fatal = false;
+
   /* Analyze data dependences between the data-refs in the loop
      and adjust the maximum vectorization factor according to
      the dependences.
@@ -2118,7 +2123,8 @@ vect_analyze_loop (struct loop *loop)
          return NULL;
        }
 
-      if (vect_analyze_loop_2 (loop_vinfo))
+      bool fatal = false;
+      if (vect_analyze_loop_2 (loop_vinfo, fatal))
        {
          LOOP_VINFO_VECTORIZABLE_P (loop_vinfo) = 1;
 
@@ -2128,7 +2134,8 @@ vect_analyze_loop (struct loop *loop)
       destroy_loop_vec_info (loop_vinfo, true);
 
       vector_sizes &= ~current_vector_size;
-      if (vector_sizes == 0
+      if (fatal
+         || vector_sizes == 0
          || current_vector_size == 0)
        return NULL;