From 70641d56fb22355a85ad142700ae721a6a293908 Mon Sep 17 00:00:00 2001
Date: Tue, 25 Jun 2019 10:40:42 +0000
Subject: [PATCH] Backport of JDK-8191955

summary: incorrect prefetch distance causes an internal error
LLT:
Bug url: https://bugs.openjdk.java.net/browse/JDK-8191955
---
 hotspot/src/cpu/aarch64/vm/vm_version_aarch64.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/hotspot/src/cpu/aarch64/vm/vm_version_aarch64.cpp b/hotspot/src/cpu/aarch64/vm/vm_version_aarch64.cpp
index f64e356558..ebdfeadf57 100644
--- a/hotspot/src/cpu/aarch64/vm/vm_version_aarch64.cpp
+++ b/hotspot/src/cpu/aarch64/vm/vm_version_aarch64.cpp
@@ -144,6 +144,17 @@ void VM_Version::get_processor_features() {
     if (PrefetchCopyIntervalInBytes >= 32768)
       PrefetchCopyIntervalInBytes = 32760;
   }
+
+  if (AllocatePrefetchDistance !=-1 && (AllocatePrefetchDistance & 7)) {
+    warning("AllocatePrefetchDistance must be multiple of 8");
+    AllocatePrefetchDistance &= ~7;
+  }
+
+  if (AllocatePrefetchStepSize & 7) {
+    warning("AllocatePrefetchStepSize must be multiple of 8");
+    AllocatePrefetchStepSize &= ~7;
+  }
+
   FLAG_SET_DEFAULT(UseSSE42Intrinsics, true);
 
   unsigned long auxv = getauxval(AT_HWCAP);
-- 
2.19.0-rc1