src/share/vm/utilities/copy.cpp
Index
Unified diffs
Context diffs
Sdiffs
Patch
New
Old
Previous File
Next File
*** old/src/share/vm/utilities/copy.cpp Tue Feb 2 10:45:47 2016
--- new/src/share/vm/utilities/copy.cpp Tue Feb 2 10:45:47 2016
*** 1,7 ****
--- 1,7 ----
/*
! * Copyright (c) 2006, 2010, Oracle and/or its affiliates. All rights reserved.
! * Copyright (c) 2006, 2016, 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.
*** 51,60 ****
--- 51,226 ----
// Not aligned, so no need to be atomic.
Copy::conjoint_jbytes((void*) src, (void*) dst, size);
}
}
+ class CopySwap : AllStatic {
+ public:
+ /**
+ * Copy and byte swap elements
+ *
+ * @param src address of source
+ * @param dst address of destination
+ * @param byte_count number of bytes to copy
+ * @param elem_size size of the elements to copy-swap
+ */
+ static void conjoint_swap(address src, address dst, size_t byte_count, size_t elem_size) {
+ address src_end = src + byte_count;
+
+ if (dst <= src || dst >= src_end) {
+ do_conjoint_swap<RIGHT>(src, dst, byte_count, elem_size);
+ } else {
+ do_conjoint_swap<LEFT>(src, dst, byte_count, elem_size);
+ }
+ }
+
+ private:
+ /**
+ * Byte swap a 16-bit value
+ */
+ static uint16_t byte_swap(uint16_t x) {
+ return (x << 8) | (x >> 8);
+ }
+
+ /**
+ * Byte swap a 32-bit value
+ */
+ static uint32_t byte_swap(uint32_t x) {
+ uint16_t lo = (uint16_t)x;
+ uint16_t hi = (uint16_t)(x >> 16);
+
+ return
+ ((uint32_t)byte_swap(lo) << 16) |
+ ((uint32_t)byte_swap(hi));
+ }
+
+ /**
+ * Byte swap a 64-bit value
+ */
+ static uint64_t byte_swap(uint64_t x) {
+ uint32_t lo = (uint32_t)x;
+ uint32_t hi = (uint32_t)(x >> 32);
+
+ return
+ ((uint64_t)byte_swap(lo) << 32) |
+ ((uint64_t)byte_swap(hi));
+ }
+
+ enum CopyDirection {
+ RIGHT, // lower -> higher address
+ LEFT // higher -> lower address
+ };
+
+ /**
+ * Copy and byte swap elements
+ *
+ * <T> - type of element to copy
+ * <D> - copy direction
+ * <is_src_aligned> - true if src argument is aligned to element size
+ * <is_dst_aligned> - true if dst argument is aligned to element size
+ *
+ * @param src address of source
+ * @param dst address of destination
+ * @param byte_count number of bytes to copy
+ */
+ template <typename T,CopyDirection D,bool is_src_aligned, bool is_dst_aligned>
+ static void do_conjoint_swap(address src, address dst, size_t byte_count) {
+ address cur_src, cur_dst;
+
+ switch (D) {
+ case RIGHT:
+ cur_src = src;
+ cur_dst = dst;
+ break;
+ case LEFT:
+ cur_src = src + byte_count - sizeof(T);
+ cur_dst = dst + byte_count - sizeof(T);
+ break;
+ }
+
+ for (size_t i = 0; i < byte_count / sizeof(T); i++) {
+ T tmp;
+
+ if (is_src_aligned) {
+ tmp = *(T*)cur_src;
+ } else {
+ memcpy(&tmp, cur_src, sizeof(T));
+ }
+
+ tmp = byte_swap(tmp);
+
+ if (is_dst_aligned) {
+ *(T*)cur_dst = tmp;
+ } else {
+ memcpy(cur_dst, &tmp, sizeof(T));
+ }
+
+ switch (D) {
+ case RIGHT:
+ cur_src += sizeof(T);
+ cur_dst += sizeof(T);
+ break;
+ case LEFT:
+ cur_src -= sizeof(T);
+ cur_dst -= sizeof(T);
+ break;
+ }
+ }
+ }
+
+ /**
+ * Copy and byte swap elements
+ *
+ * <T> - type of element to copy
+ * <D> - copy direction
+ *
+ * @param src address of source
+ * @param dst address of destination
+ * @param byte_count number of bytes to copy
+ */
+ template <typename T, CopyDirection direction>
+ static void do_conjoint_swap(address src, address dst, size_t byte_count) {
+ if (is_ptr_aligned(src, sizeof(T))) {
+ if (is_ptr_aligned(dst, sizeof(T))) {
+ do_conjoint_swap<T,direction,true,true>(src, dst, byte_count);
+ } else {
+ do_conjoint_swap<T,direction,true,false>(src, dst, byte_count);
+ }
+ } else {
+ if (is_ptr_aligned(dst, sizeof(T))) {
+ do_conjoint_swap<T,direction,false,true>(src, dst, byte_count);
+ } else {
+ do_conjoint_swap<T,direction,false,false>(src, dst, byte_count);
+ }
+ }
+ }
+
+
+ /**
+ * Copy and byte swap elements
+ *
+ * <D> - copy direction
+ *
+ * @param src address of source
+ * @param dst address of destination
+ * @param byte_count number of bytes to copy
+ * @param elem_size size of the elements to copy-swap
+ */
+ template <CopyDirection D>
+ static void do_conjoint_swap(address src, address dst, size_t byte_count, size_t elem_size) {
+ switch (elem_size) {
+ case 2: do_conjoint_swap<uint16_t,D>(src, dst, byte_count); break;
+ case 4: do_conjoint_swap<uint32_t,D>(src, dst, byte_count); break;
+ case 8: do_conjoint_swap<uint64_t,D>(src, dst, byte_count); break;
+ default: guarantee(false, "do_conjoint_swap: Invalid elem_size %zd\n", elem_size);
+ }
+ }
+ };
+
+ void Copy::conjoint_swap(address src, address dst, size_t byte_count, size_t elem_size) {
+ CopySwap::conjoint_swap(src, dst, byte_count, elem_size);
+ }
// Fill bytes; larger units are filled atomically if everything is aligned.
void Copy::fill_to_memory_atomic(void* to, size_t size, jubyte value) {
address dst = (address) to;
uintptr_t bits = (uintptr_t) to | (uintptr_t) size;
src/share/vm/utilities/copy.cpp
Index
Unified diffs
Context diffs
Sdiffs
Patch
New
Old
Previous File
Next File