tree-vect-data-refs.c (vect_shift_permute_load_chain): Extend shift permutations…

tree-vect-data-refs.c (vect_shift_permute_load_chain): Extend shift permutations on power of 2 cases.

gcc/

        * tree-vect-data-refs.c (vect_shift_permute_load_chain): Extend shift
	permutations on power of 2 cases.

gcc/testsuites/

	* gcc.target/i386/pr52252-atom-1.c: New.

From-SVN: r217359

gcc/ChangeLog

+2014-11-11  Evgeny Stupachenko  <evstupac@gmail.com>
+
+        * tree-vect-data-refs.c (vect_shift_permute_load_chain): Extend shift
+	permutations on power of 2 cases.
+
 2014-11-11  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	* config/aarch64/aarch64.h (MACHMODE): Remove 'enum' keyword.

gcc/testsuite/ChangeLog

+2014-11-11  Evgeny Stupachenko  <evstupac@gmail.com>
+
+	* gcc.target/i386/pr52252-atom-1.c: New.
+
 2014-11-11  Martin Liska  <mliska@suse.cz>
 
 	PR ipa/63622

gcc/testsuite/gcc.target/i386/pr52252-atom-1.c

+/* { dg-do compile } */
+/* { dg-require-effective-target ssse3 } */
+/* { dg-options "-O2 -ftree-vectorize -mssse3 -mtune=slm" } */
+#define byte unsigned char
+
+void
+pair_mul_sum(byte *in, byte *out, int size)
+{
+  int j;
+  for(j = 0; j < size; j++)
+    {
+      byte a = in[0];
+      byte b = in[1];
+      byte c = in[2];
+      byte d = in[3];
+      out[0] = (byte)(a * b) + (byte)(b * c) + (byte)(c * d) + (byte)(d * a);
+      in += 4;
+      out += 1;
+    }
+}
+
+/* { dg-final { scan-assembler "palignr" } } */

gcc/tree-vect-data-refs.c

@@ -5371,8 +5371,9 @@ vect_shift_permute_load_chain (vec<tree> dr_chain,
   memcpy (result_chain->address (), dr_chain.address (),
 	  length * sizeof (tree));
 
-  if (length == 2 && LOOP_VINFO_VECT_FACTOR (loop_vinfo) > 4)
+  if (exact_log2 (length) != -1 && LOOP_VINFO_VECT_FACTOR (loop_vinfo) > 4)
     {
+      unsigned int j, log_length = exact_log2 (length);
       for (i = 0; i < nelt / 2; ++i)
 	sel[i] = i * 2;
       for (i = 0; i < nelt / 2; ++i)
@@ -5433,8 +5434,12 @@ vect_shift_permute_load_chain (vec<tree> dr_chain,
       select_mask = vect_gen_perm_mask (vectype, sel);
       gcc_assert (select_mask != NULL);
 
-      first_vect = dr_chain[0];
-      second_vect = dr_chain[1];
+      for (i = 0; i < log_length; i++)
+	{
+	  for (j = 0; j < length; j += 2)
+	    {
+	      first_vect = dr_chain[j];
+	      second_vect = dr_chain[j + 1];
 
 	      data_ref = make_temp_ssa_name (vectype, NULL, "vect_shuffle2");
 	      perm_stmt = gimple_build_assign_with_ops (VEC_PERM_EXPR, data_ref,
@@ -5455,15 +5460,18 @@ vect_shift_permute_load_chain (vec<tree> dr_chain,
 							vect[0], vect[1],
 							shift1_mask);
 	      vect_finish_stmt_generation (stmt, perm_stmt, gsi);
-      (*result_chain)[1] = data_ref;
+	      (*result_chain)[j/2 + length/2] = data_ref;
 
 	      data_ref = make_temp_ssa_name (vectype, NULL, "vect_select");
 	      perm_stmt = gimple_build_assign_with_ops (VEC_PERM_EXPR, data_ref,
 							vect[0], vect[1],
 							select_mask);
 	      vect_finish_stmt_generation (stmt, perm_stmt, gsi);
-      (*result_chain)[0] = data_ref;
-
+	      (*result_chain)[j/2] = data_ref;
+	    }
+	  memcpy (dr_chain.address (), result_chain->address (),
+		  length * sizeof (tree));
+	}
       return true;
     }
   if (length == 3 && LOOP_VINFO_VECT_FACTOR (loop_vinfo) > 2)