Add __memcpy_chk assembly for 64 bit.
Bug: 17623887
(cherry picked from commit 8cf61dab5f11ed5654a5760ab47cec0239caafe0)
Change-Id: I91e66ca0c26f04b50308059f9c89d388d55f6e3a
diff --git a/libc/arch-arm64/generic/bionic/memcpy_base.S b/libc/arch-arm64/generic/bionic/memcpy_base.S
new file mode 100644
index 0000000..c5d42ce
--- /dev/null
+++ b/libc/arch-arm64/generic/bionic/memcpy_base.S
@@ -0,0 +1,179 @@
+/* Copyright (c) 2012, Linaro Limited
+ All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+ * Neither the name of the Linaro nor the
+ names of its contributors may be used to endorse or promote products
+ derived from this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* Assumptions:
+ *
+ * ARMv8-a, AArch64
+ * Unaligned accesses
+ *
+ */
+
+#define dstin x0
+#define src x1
+#define count x2
+#define tmp1 x3
+#define tmp1w w3
+#define tmp2 x4
+#define tmp2w w4
+#define tmp3 x5
+#define tmp3w w5
+#define dst x6
+
+#define A_l x7
+#define A_h x8
+#define B_l x9
+#define B_h x10
+#define C_l x11
+#define C_h x12
+#define D_l x13
+#define D_h x14
+
+ mov dst, dstin
+ cmp count, #64
+ b.ge .Lcpy_not_short
+ cmp count, #15
+ b.le .Ltail15tiny
+
+ /* Deal with small copies quickly by dropping straight into the
+ * exit block. */
+.Ltail63:
+ /* Copy up to 48 bytes of data. At this point we only need the
+ * bottom 6 bits of count to be accurate. */
+ ands tmp1, count, #0x30
+ b.eq .Ltail15
+ add dst, dst, tmp1
+ add src, src, tmp1
+ cmp tmp1w, #0x20
+ b.eq 1f
+ b.lt 2f
+ ldp A_l, A_h, [src, #-48]
+ stp A_l, A_h, [dst, #-48]
+1:
+ ldp A_l, A_h, [src, #-32]
+ stp A_l, A_h, [dst, #-32]
+2:
+ ldp A_l, A_h, [src, #-16]
+ stp A_l, A_h, [dst, #-16]
+
+.Ltail15:
+ ands count, count, #15
+ beq 1f
+ add src, src, count
+ ldp A_l, A_h, [src, #-16]
+ add dst, dst, count
+ stp A_l, A_h, [dst, #-16]
+1:
+ ret
+
+.Ltail15tiny:
+ /* Copy up to 15 bytes of data. Does not assume additional data
+ being copied. */
+ tbz count, #3, 1f
+ ldr tmp1, [src], #8
+ str tmp1, [dst], #8
+1:
+ tbz count, #2, 1f
+ ldr tmp1w, [src], #4
+ str tmp1w, [dst], #4
+1:
+ tbz count, #1, 1f
+ ldrh tmp1w, [src], #2
+ strh tmp1w, [dst], #2
+1:
+ tbz count, #0, 1f
+ ldrb tmp1w, [src]
+ strb tmp1w, [dst]
+1:
+ ret
+
+.Lcpy_not_short:
+ /* We don't much care about the alignment of DST, but we want SRC
+ * to be 128-bit (16 byte) aligned so that we don't cross cache line
+ * boundaries on both loads and stores. */
+ neg tmp2, src
+ ands tmp2, tmp2, #15 /* Bytes to reach alignment. */
+ b.eq 2f
+ sub count, count, tmp2
+ /* Copy more data than needed; it's faster than jumping
+ * around copying sub-Quadword quantities. We know that
+ * it can't overrun. */
+ ldp A_l, A_h, [src]
+ add src, src, tmp2
+ stp A_l, A_h, [dst]
+ add dst, dst, tmp2
+ /* There may be less than 63 bytes to go now. */
+ cmp count, #63
+ b.le .Ltail63
+2:
+ subs count, count, #128
+ b.ge .Lcpy_body_large
+ /* Less than 128 bytes to copy, so handle 64 here and then jump
+ * to the tail. */
+ ldp A_l, A_h, [src]
+ ldp B_l, B_h, [src, #16]
+ ldp C_l, C_h, [src, #32]
+ ldp D_l, D_h, [src, #48]
+ stp A_l, A_h, [dst]
+ stp B_l, B_h, [dst, #16]
+ stp C_l, C_h, [dst, #32]
+ stp D_l, D_h, [dst, #48]
+ tst count, #0x3f
+ add src, src, #64
+ add dst, dst, #64
+ b.ne .Ltail63
+ ret
+
+ /* Critical loop. Start at a new cache line boundary. Assuming
+ * 64 bytes per line this ensures the entire loop is in one line. */
+ .p2align 6
+.Lcpy_body_large:
+ /* There are at least 128 bytes to copy. */
+ ldp A_l, A_h, [src, #0]
+ sub dst, dst, #16 /* Pre-bias. */
+ ldp B_l, B_h, [src, #16]
+ ldp C_l, C_h, [src, #32]
+ ldp D_l, D_h, [src, #48]! /* src += 64 - Pre-bias. */
+1:
+ stp A_l, A_h, [dst, #16]
+ ldp A_l, A_h, [src, #16]
+ stp B_l, B_h, [dst, #32]
+ ldp B_l, B_h, [src, #32]
+ stp C_l, C_h, [dst, #48]
+ ldp C_l, C_h, [src, #48]
+ stp D_l, D_h, [dst, #64]!
+ ldp D_l, D_h, [src, #64]!
+ subs count, count, #64
+ b.ge 1b
+ stp A_l, A_h, [dst, #16]
+ stp B_l, B_h, [dst, #32]
+ stp C_l, C_h, [dst, #48]
+ stp D_l, D_h, [dst, #64]
+ add src, src, #16
+ add dst, dst, #64 + 16
+ tst count, #0x3f
+ b.ne .Ltail63
+ ret