--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/jfr/writers/jfrEncoders.hpp Tue May 15 20:24:34 2018 +0200
@@ -0,0 +1,298 @@
+/*
+ * Copyright (c) 2015, 2018, 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.
+ *
+ */
+
+#ifndef SHARE_VM_JFR_WRITERS_JFRENCODERS_HPP
+#define SHARE_VM_JFR_WRITERS_JFRENCODERS_HPP
+
+#include "memory/allocation.hpp"
+#include "utilities/bytes.hpp"
+#include "utilities/debug.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+//
+// The Encoding policy prescribes a template
+// method taking a first parameter of type T.
+// This is the value to be encoded. The second
+// parameter is a memory address - where to write
+// the encoded value.
+// The encoder method(s) should return the
+// number of bytes encoded into that memory address.
+//
+// template <typename T>
+// size_t encoder(T value, u1* dest);
+//
+// The caller ensures the destination
+// address is not null and that T can be fitted
+// in encoded form.
+//
+
+// Encoding policy classes
+
+class BigEndianEncoderImpl {
+ public:
+ template <typename T>
+ static size_t encode(T value, u1* dest);
+
+ template <typename T>
+ static size_t encode(const T* src, size_t len, u1* dest);
+
+ template <typename T>
+ static size_t encode_padded(T value, u1* dest);
+
+ template <typename T>
+ static size_t encode_padded(const T* src, size_t len, u1* dest);
+
+};
+
+template <typename T>
+inline size_t BigEndianEncoderImpl::encode(T value, u1* dest) {
+ assert(dest != NULL, "invariant");
+ switch (sizeof(T)) {
+ case 1: {
+ ShouldNotReachHere();
+ return 0;
+ }
+ case 2: {
+ Bytes::put_Java_u2(dest, value);
+ return 2;
+ }
+ case 4: {
+ Bytes::put_Java_u4(dest, value);
+ return 4;
+ }
+ case 8: {
+ Bytes::put_Java_u8(dest, value);
+ return 8;
+ }
+ }
+ ShouldNotReachHere();
+ return 0;
+}
+
+template <typename T>
+inline size_t BigEndianEncoderImpl::encode(const T* src, size_t len, u1* dest) {
+ assert(dest != NULL, "invariant");
+ assert(len >= 1, "invariant");
+ if (1 == sizeof(T)) {
+ memcpy(dest, src, len);
+ return len;
+ }
+ size_t size = encode(*src, dest);
+ if (len > 1) {
+ for (size_t i = 1; i < len; ++i) {
+ size += encode(*(src + i), dest + size);
+ }
+ }
+ return size;
+}
+
+template <typename T>
+inline size_t BigEndianEncoderImpl::encode_padded(T value, u1* dest) {
+ return encode(value, dest);
+}
+
+template <typename T>
+inline size_t BigEndianEncoderImpl::encode_padded(const T* src, size_t len, u1* dest) {
+ assert(dest != NULL, "invariant");
+ assert(len >= 1, "invariant");
+ if (1 == sizeof(T)) {
+ memcpy(dest, src, len);
+ return len;
+ }
+ size_t size = encode_padded(*src, dest);
+ if (len > 1) {
+ for (size_t i = 1; i < len; ++i) {
+ size += encode_padded(*(src + i), dest + size);
+ }
+ }
+ return size;
+}
+
+
+// The Varint128 encoder implements encoding according to
+// msb(it) 128bit encoding (1 encode bit | 7 value bits),
+// using least significant byte order.
+//
+// Example (little endian platform):
+// Value: 25674
+// Binary: 00000000 0000000 01100100 01001010
+// Varint encoded (3 bytes):
+// Value: 13289473
+// Varint encoded: 11001010 11001000 00000001
+//
+
+class Varint128EncoderImpl {
+ private:
+ template <typename T>
+ static u8 to_u8(T value);
+
+ public:
+ template <typename T>
+ static size_t encode(T value, u1* dest);
+
+ template <typename T>
+ static size_t encode(const T* src, size_t len, u1* dest);
+
+ template <typename T>
+ static size_t encode_padded(T value, u1* dest);
+
+ template <typename T>
+ static size_t encode_padded(const T* src, size_t len, u1* dest);
+
+};
+
+template <typename T>
+inline u8 Varint128EncoderImpl::to_u8(T value) {
+ switch(sizeof(T)) {
+ case 1:
+ return static_cast<u8>(static_cast<u1>(value) & static_cast<u1>(0xff));
+ case 2:
+ return static_cast<u8>(static_cast<u2>(value) & static_cast<u2>(0xffff));
+ case 4:
+ return static_cast<u8>(static_cast<u4>(value) & static_cast<u4>(0xffffffff));
+ case 8:
+ return static_cast<u8>(value);
+ default:
+ fatal("unsupported type");
+ }
+ return 0;
+}
+
+static const u1 ext_bit = 0x80;
+#define GREATER_THAN_OR_EQUAL_TO_128(v) (((u8)(~(ext_bit - 1)) & (v)))
+#define LESS_THAN_128(v) !GREATER_THAN_OR_EQUAL_TO_128(v)
+
+template <typename T>
+inline size_t Varint128EncoderImpl::encode(T value, u1* dest) {
+ assert(dest != NULL, "invariant");
+
+ const u8 v = to_u8(value);
+
+ if (LESS_THAN_128(v)) {
+ *dest = static_cast<u1>(v); // set bit 0-6, no extension
+ return 1;
+ }
+ *dest = static_cast<u1>(v | ext_bit); // set bit 0-6, with extension
+ if (LESS_THAN_128(v >> 7)) {
+ *(dest + 1) = static_cast<u1>(v >> 7); // set bit 7-13, no extension
+ return 2;
+ }
+ *(dest + 1) = static_cast<u1>((v >> 7) | ext_bit); // set bit 7-13, with extension
+ if (LESS_THAN_128(v >> 14)) {
+ *(dest + 2) = static_cast<u1>(v >> 14); // set bit 14-20, no extension
+ return 3;
+ }
+ *(dest + 2) = static_cast<u1>((v >> 14) | ext_bit); // set bit 14-20, with extension
+ if (LESS_THAN_128(v >> 21)) {
+ *(dest + 3) = static_cast<u1>(v >> 21); // set bit 21-27, no extension
+ return 4;
+ }
+ *(dest + 3) = static_cast<u1>((v >> 21) | ext_bit); // set bit 21-27, with extension
+ if (LESS_THAN_128(v >> 28)) {
+ *(dest + 4) = static_cast<u1>(v >> 28); // set bit 28-34, no extension
+ return 5;
+ }
+ *(dest + 4) = static_cast<u1>((v >> 28) | ext_bit); // set bit 28-34, with extension
+ if (LESS_THAN_128(v >> 35)) {
+ *(dest + 5) = static_cast<u1>(v >> 35); // set bit 35-41, no extension
+ return 6;
+ }
+ *(dest + 5) = static_cast<u1>((v >> 35) | ext_bit); // set bit 35-41, with extension
+ if (LESS_THAN_128(v >> 42)) {
+ *(dest + 6) = static_cast<u1>(v >> 42); // set bit 42-48, no extension
+ return 7;
+ }
+ *(dest + 6) = static_cast<u1>((v >> 42) | ext_bit); // set bit 42-48, with extension
+ if (LESS_THAN_128(v >> 49)) {
+ *(dest + 7) = static_cast<u1>(v >> 49); // set bit 49-55, no extension
+ return 8;
+ }
+ *(dest + 7) = static_cast<u1>((v >> 49) | ext_bit); // set bit 49-55, with extension
+ // no need to extend since only 64 bits allowed.
+ *(dest + 8) = static_cast<u1>(v >> 56); // set bit 56-63
+ return 9;
+}
+
+template <typename T>
+inline size_t Varint128EncoderImpl::encode(const T* src, size_t len, u1* dest) {
+ assert(dest != NULL, "invariant");
+ assert(len >= 1, "invariant");
+ size_t size = encode(*src, dest);
+ if (len > 1) {
+ for (size_t i = 1; i < len; ++i) {
+ size += encode(*(src + i), dest + size);
+ }
+ }
+ return size;
+}
+
+template <typename T>
+inline size_t Varint128EncoderImpl::encode_padded(T value, u1* dest) {
+ assert(dest != NULL, "invariant");
+ const u8 v = to_u8(value);
+ switch (sizeof(T)) {
+ case 1:
+ dest[0] = static_cast<u1>(v);
+ return 1;
+ case 2:
+ dest[0] = static_cast<u1>(v | 0x80);
+ dest[1] = static_cast<u1>(v >> 7);
+ return 2;
+ case 4:
+ dest[0] = static_cast<u1>(v | 0x80);
+ dest[1] = static_cast<u1>(v >> 7 | 0x80);
+ dest[2] = static_cast<u1>(v >> 14 | 0x80);
+ dest[3] = static_cast<u1>(v >> 21);
+ return 4;
+ case 8:
+ dest[0] = static_cast<u1>(v | 0x80);
+ dest[1] = static_cast<u1>(v >> 7 | 0x80);
+ dest[2] = static_cast<u1>(v >> 14 | 0x80);
+ dest[3] = static_cast<u1>(v >> 21 | 0x80);
+ dest[4] = static_cast<u1>(v >> 28 | 0x80);
+ dest[5] = static_cast<u1>(v >> 35 | 0x80);
+ dest[6] = static_cast<u1>(v >> 42 | 0x80);
+ dest[7] = static_cast<u1>(v >> 49);
+ return 8;
+ default:
+ ShouldNotReachHere();
+ }
+ return 0;
+}
+
+
+template <typename T>
+inline size_t Varint128EncoderImpl::encode_padded(const T* src, size_t len, u1* dest) {
+ assert(dest != NULL, "invariant");
+ assert(len >= 1, "invariant");
+ size_t size = encode_padded(*src, dest);
+ if (len > 1) {
+ for (size_t i = 1; i < len; ++i) {
+ size += encode_padded(*(src + i), dest + size);
+ }
+ }
+ return size;
+}
+
+#endif // SHARE_VM_JFR_WRITERS_JFRENCODERS_HPP