# HG changeset patch

# User aph

# Date 1338206478 14400

#      Mon May 28 08:01:18 2012 -0400

# Node ID 6275d7b419091092752d5a1854194c98897892ba

# Parent  be1379a186ba527b32c93a83e04c9600735fe44b

PR3559: Use ldrexd for atomic reads on ARMv7.

2012-05-28  Andrew Haley  <aph@redhat.com>

	* os_linux_zero.hpp (atomic_copy64): Use ldrexd for atomic reads

	on ARMv7.

diff --git openjdk.orig/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.hpp openjdk/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.hpp

--- openjdk.orig/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.hpp

+++ openjdk/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.hpp

@@ -54,6 +54,12 @@

                   "std %0, 0(%2)\n"

                   : "=r"(tmp)

                   : "a"(src), "a"(dst));

+#elif defined(__ARM_ARCH_7A__)

+    jlong tmp;

+    asm volatile ("ldrexd  %0, [%1]\n"

+                  : "=r"(tmp)

+                  : "r"(src), "m"(src));

+    *(jlong *) dst = tmp;

 #else

     *(jlong *) dst = *(jlong *) src;

 #endif