Merge "Update linker README."
diff --git a/libc/Android.mk b/libc/Android.mk
index 83d8e59..708624d 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -182,7 +182,6 @@
bionic/md5.c \
bionic/memchr.c \
bionic/memmem.c \
- bionic/memmove_words.c \
bionic/memrchr.c \
bionic/memswap.c \
bionic/mmap.c \
diff --git a/libc/bionic/memmove_words.c b/libc/bionic/memmove_words.c
deleted file mode 100644
index 26df7fa..0000000
--- a/libc/bionic/memmove_words.c
+++ /dev/null
@@ -1,148 +0,0 @@
-/*
- * Copyright (C) 2011 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <stdlib.h>
-#include <stdint.h>
-#include <assert.h>
-
-/*
- * Works like memmove(), except:
- * - if all arguments are at least 32-bit aligned, we guarantee that we
- * will use operations that preserve atomicity of 32-bit values
- * - if not, we guarantee atomicity of 16-bit values
- *
- * If all three arguments are not at least 16-bit aligned, the behavior
- * of this function is undefined. (We could remove this restriction by
- * testing for unaligned values and punting to memmove(), but that's
- * not currently useful.)
- *
- * TODO: add loop for 64-bit alignment
- * TODO: use __builtin_prefetch
- * TODO: write an ARM-optimized version
- */
-void _memmove_words(void* dest, const void* src, size_t n)
-{
- assert((((uintptr_t) dest | (uintptr_t) src | n) & 0x01) == 0);
-
- char* d = (char*) dest;
- const char* s = (const char*) src;
- size_t copyCount;
-
- /*
- * If the source and destination pointers are the same, this is
- * an expensive no-op. Testing for an empty move now allows us
- * to skip a check later.
- */
- if (n == 0 || d == s)
- return;
-
- /*
- * Determine if the source and destination buffers will overlap if
- * we copy data forward (i.e. *dest++ = *src++).
- *
- * It's okay if the destination buffer starts before the source and
- * there is some overlap, because the reader is always ahead of the
- * writer.
- */
- if (__builtin_expect((d < s) || ((size_t)(d - s) >= n), 1)) {
- /*
- * Copy forward. We prefer 32-bit loads and stores even for 16-bit
- * data, so sort that out.
- */
- if ((((uintptr_t) d | (uintptr_t) s) & 0x03) != 0) {
- /*
- * Not 32-bit aligned. Two possibilities:
- * (1) Congruent, we can align to 32-bit by copying one 16-bit val
- * (2) Non-congruent, we can do one of:
- * a. copy whole buffer as a series of 16-bit values
- * b. load/store 32 bits, using shifts to ensure alignment
- * c. just copy the as 32-bit values and assume the CPU
- * will do a reasonable job
- *
- * We're currently using (a), which is suboptimal.
- */
- if ((((uintptr_t) d ^ (uintptr_t) s) & 0x03) != 0) {
- copyCount = n;
- } else {
- copyCount = 2;
- }
- n -= copyCount;
- copyCount /= sizeof(uint16_t);
-
- while (copyCount--) {
- *(uint16_t*)d = *(uint16_t*)s;
- d += sizeof(uint16_t);
- s += sizeof(uint16_t);
- }
- }
-
- /*
- * Copy 32-bit aligned words.
- */
- copyCount = n / sizeof(uint32_t);
- while (copyCount--) {
- *(uint32_t*)d = *(uint32_t*)s;
- d += sizeof(uint32_t);
- s += sizeof(uint32_t);
- }
-
- /*
- * Check for leftovers. Either we finished exactly, or we have
- * one remaining 16-bit chunk.
- */
- if ((n & 0x02) != 0) {
- *(uint16_t*)d = *(uint16_t*)s;
- }
- } else {
- /*
- * Copy backward, starting at the end.
- */
- d += n;
- s += n;
-
- if ((((uintptr_t) d | (uintptr_t) s) & 0x03) != 0) {
- /* try for 32-bit alignment */
- if ((((uintptr_t) d ^ (uintptr_t) s) & 0x03) != 0) {
- copyCount = n;
- } else {
- copyCount = 2;
- }
- n -= copyCount;
- copyCount /= sizeof(uint16_t);
-
- while (copyCount--) {
- d -= sizeof(uint16_t);
- s -= sizeof(uint16_t);
- *(uint16_t*)d = *(uint16_t*)s;
- }
- }
-
- /* copy 32-bit aligned words */
- copyCount = n / sizeof(uint32_t);
- while (copyCount--) {
- d -= sizeof(uint32_t);
- s -= sizeof(uint32_t);
- *(uint32_t*)d = *(uint32_t*)s;
- }
-
- /* copy leftovers */
- if ((n & 0x02) != 0) {
- d -= sizeof(uint16_t);
- s -= sizeof(uint16_t);
- *(uint16_t*)d = *(uint16_t*)s;
- }
- }
-}