diff -r 4ebc2e2fb97c -r 71c04702a3d5 src/hotspot/share/runtime/icache.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/icache.cpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "memory/resourceArea.hpp"
+#include "runtime/icache.hpp"
+#include "utilities/align.hpp"
+
+// The flush stub function address
+AbstractICache::flush_icache_stub_t AbstractICache::_flush_icache_stub = NULL;
+
+void AbstractICache::initialize() {
+  // Making this stub must be FIRST use of assembler
+  ResourceMark rm;
+
+  BufferBlob* b = BufferBlob::create("flush_icache_stub", ICache::stub_size);
+  if (b == NULL) {
+    vm_exit_out_of_memory(ICache::stub_size, OOM_MALLOC_ERROR, "CodeCache: no space for flush_icache_stub");
+  }
+  CodeBuffer c(b);
+
+  ICacheStubGenerator g(&c);
+  g.generate_icache_flush(&_flush_icache_stub);
+
+  // The first use of flush_icache_stub must apply it to itself.
+  // The StubCodeMark destructor in generate_icache_flush will
+  // call Assembler::flush, which in turn will call invalidate_range,
+  // which will in turn call the flush stub.  Thus we don't need an
+  // explicit call to invalidate_range here.  This assumption is
+  // checked in invalidate_range.
+}
+
+void AbstractICache::call_flush_stub(address start, int lines) {
+  // The business with the magic number is just a little security.
+  // We cannot call the flush stub when generating the flush stub
+  // because it isn't there yet.  So, the stub also returns its third
+  // parameter.  This is a cheap check that the stub was really executed.
+  static int magic = 0xbaadbabe;
+
+  int auto_magic = magic; // Make a local copy to avoid race condition
+  int r = (*_flush_icache_stub)(start, lines, auto_magic);
+  guarantee(r == auto_magic, "flush stub routine did not execute");
+  ++magic;
+}
+
+void AbstractICache::invalidate_word(address addr) {
+  // Because this is called for instruction patching on the fly, long after
+  // bootstrapping, we execute the stub directly.  Account for a 4-byte word
+  // spanning two cache lines by computing a start line address by rounding
+  // addr down to a line_size boundary, and an end line address by adding
+  // the word size - 1 and rounding the result down to a line_size boundary.
+  // If we just added word size, we'd mistakenly flush the next cache line
+  // if the word to be flushed started in the last 4 bytes of the line.
+  // Doing that would segv if the next line weren't mapped.
+
+  const int word_size_in_bytes = 4; // Always, regardless of platform
+
+  intptr_t start_line = ((intptr_t)addr + 0) & ~(ICache::line_size - 1);
+  intptr_t end_line   = ((intptr_t)addr + word_size_in_bytes - 1)
+                                             & ~(ICache::line_size - 1);
+  (*_flush_icache_stub)((address)start_line, start_line == end_line ? 1 : 2, 0);
+}
+
+void AbstractICache::invalidate_range(address start, int nbytes) {
+  static bool firstTime = true;
+  if (firstTime) {
+    guarantee(start == CAST_FROM_FN_PTR(address, _flush_icache_stub),
+              "first flush should be for flush stub");
+    firstTime = false;
+    return;
+  }
+  if (nbytes == 0) {
+    return;
+  }
+  // Align start address to an icache line boundary and transform
+  // nbytes to an icache line count.
+  const uint line_offset = mask_address_bits(start, ICache::line_size-1);
+  if (line_offset != 0) {
+    start -= line_offset;
+    nbytes += line_offset;
+  }
+  call_flush_stub(start, align_up(nbytes, (int)ICache::line_size) >>
+                         ICache::log2_line_size);
+}
+
+// For init.cpp
+void icache_init() {
+  ICache::initialize();
+}