rs6000.md (prefetch): Generate ISA 2.06 instructions dcbtt and dcbtstt if operands[2] is 0.

gcc/ChangeLog:

2018-05-10  Carl Love  <cel@us.ibm.com>

	* config/rs6000/rs6000.md (prefetch): Generate ISA 2.06 instructions
	dcbtt and dcbtstt if operands[2] is 0.

From-SVN: r260134

gcc/ChangeLog

+2018-05-10  Carl Love  <cel@us.ibm.com>
+
+	* config/rs6000/rs6000.md (prefetch): Generate ISA 2.06 instructions
+	dcbtt and dcbtstt if operands[2] is 0.
+
 2018-05-10  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR target/85693

gcc/config/rs6000/rs6000.md

@@ -13166,9 +13166,23 @@
 	     (match_operand:SI 2 "const_int_operand" "n"))]
   ""
 {
-  if (GET_CODE (operands[0]) == REG)
-    return INTVAL (operands[1]) ? "dcbtst 0,%0" : "dcbt 0,%0";
-  return INTVAL (operands[1]) ? "dcbtst %a0" : "dcbt %a0";
+  /* dcbtstt, dcbtt and TM=0b10000 support starts with ISA 2.06.  */
+  int inst_select = INTVAL (operands[2]) || !TARGET_POPCNTD;
+
+  if (REG_P (operands[0]))
+    {
+      if (INTVAL (operands[1]) == 0)
+        return inst_select ? "dcbt 0,%0" : "dcbtt 0,%0";
+      else
+        return inst_select ? "dcbtst 0,%0" : "dcbtstt 0,%0";
+    }
+  else
+    {
+      if (INTVAL (operands[1]) == 0)
+        return inst_select ? "dcbt %a0" : "dcbtt %a0";
+      else
+        return inst_select ? "dcbtst %a0" : "dcbtstt %a0";
+    }
 }
   [(set_attr "type" "load")])