src/cpu/ppc/vm/vm_version_ppc.cpp

rev 8691 : 8131048: ppc: implement CRC32 intrinsic
Reviewed-by: kvn, simonis
Contributed-by: lutz.schmidt@sap.com

@@ -157,14 +157,22 @@
     AllocatePrefetchStyle = 1; // Fall back if inappropriate.
   }
 
   assert(AllocatePrefetchStyle >= 0, "AllocatePrefetchStyle should be positive");
 
-  if (UseCRC32Intrinsics) {
-    if (!FLAG_IS_DEFAULT(UseCRC32Intrinsics))
-      warning("CRC32 intrinsics  are not available on this CPU");
-    FLAG_SET_DEFAULT(UseCRC32Intrinsics, false);
+  // Implementation does not use any of the vector instructions
+  // available with Power8. Their exploitation is still pending.
+  if (!UseCRC32Intrinsics) {
+    if (FLAG_IS_DEFAULT(UseCRC32Intrinsics)) {
+      FLAG_SET_DEFAULT(UseCRC32Intrinsics, true);
+    }
+  }
+
+  if (UseCRC32CIntrinsics) {
+    if (!FLAG_IS_DEFAULT(UseCRC32CIntrinsics))
+      warning("CRC32C intrinsics are not available on this CPU");
+    FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);
   }
 
   // The AES intrinsic stubs require AES instruction support.
   if (UseAES) {
     warning("AES instructions are not available on this CPU");

@@ -190,16 +198,10 @@
     FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);
     FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);
     FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);
   }
 
-  if (UseCRC32CIntrinsics) {
-    if (!FLAG_IS_DEFAULT(UseCRC32CIntrinsics))
-      warning("CRC32C intrinsics are not available on this CPU");
-    FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);
-  }
-
   if (FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) {
     UseMultiplyToLenIntrinsic = true;
   }
 
   // Adjust RTM (Restricted Transactional Memory) flags.