genmatch.c (expr::gen_transform): Shortcut re-simplifying of converts to avoid…

genmatch.c (expr::gen_transform): Shortcut re-simplifying of converts to avoid uninteresting noise from the...

2015-07-01  Richard Biener <rguenther@suse.de>

	* genmatch.c (expr::gen_transform): Shortcut re-simplifying
	of converts to avoid uninteresting noise from the conversion
	simplifying patterns.

From-SVN: r225223

gcc/ChangeLog

+2015-07-01  Richard Biener <rguenther@suse.de>
+
+	* genmatch.c (expr::gen_transform): Shortcut re-simplifying
+	of converts to avoid uninteresting noise from the conversion
+	simplifying patterns.
+
 2015-06-30  Sandra Loosemore <sandra@codesourcery.com>
 
 	* config/c6x/c6x.c (try_rename_operands): Do not depend on

gcc/genmatch.c

@@ -1740,6 +1740,10 @@ expr::gen_transform (FILE *f, const char *dest, bool gimple, int depth,
 
   if (gimple)
     {
+      if (*operation == CONVERT_EXPR)
+	fprintf (f, "  if (%s != TREE_TYPE (ops%d[0])\n"
+	    "      && !useless_type_conversion_p (%s, TREE_TYPE (ops%d[0])))\n"
+	    "  {\n", type, depth, type, depth);
       /* ???  Building a stmt can fail for various reasons here, seq being
          NULL or the stmt referencing SSA names occuring in abnormal PHIs.
 	 So if we fail here we should continue matching other patterns.  */
@@ -1752,9 +1756,15 @@ expr::gen_transform (FILE *f, const char *dest, bool gimple, int depth,
 	       ops.length (), type);
       fprintf (f, "  res = maybe_push_res_to_seq (tem_code, %s, tem_ops, seq);\n"
 	       "  if (!res) return false;\n", type);
+      if (*operation == CONVERT_EXPR)
+        fprintf (f, "  }\n"
+		 "  else\n"
+		 "    res = ops%d[0];\n", depth);
     }
   else
     {
+      if (*operation == CONVERT_EXPR)
+	fprintf (f, "  if (TREE_TYPE (ops%d[0]) != %s)\n", depth, type);
       if (operation->kind == id_base::CODE)
 	fprintf (f, "  res = fold_build%d_loc (loc, %s, %s",
 		 ops.length(), opr, type);
@@ -1764,6 +1774,9 @@ expr::gen_transform (FILE *f, const char *dest, bool gimple, int depth,
       for (unsigned i = 0; i < ops.length (); ++i)
 	fprintf (f, ", ops%d[%u]", depth, i);
       fprintf (f, ");\n");
+      if (*operation == CONVERT_EXPR)
+	fprintf (f, "  else\n"
+		 "    res = ops%d[0];\n", depth);
     }
   fprintf (f, "%s = res;\n", dest);
   fprintf (f, "}\n");