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Diffstat (limited to 'ports/sysdeps/aarch64/memcpy.S')
-rw-r--r--ports/sysdeps/aarch64/memcpy.S176
1 files changed, 0 insertions, 176 deletions
diff --git a/ports/sysdeps/aarch64/memcpy.S b/ports/sysdeps/aarch64/memcpy.S
deleted file mode 100644
index caf2ab2e4f..0000000000
--- a/ports/sysdeps/aarch64/memcpy.S
+++ /dev/null
@@ -1,176 +0,0 @@
-/* Copyright (C) 2012-2014 Free Software Foundation, Inc.
-
- This file is part of the GNU C Library.
-
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
-
- The GNU C Library 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
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library. If not, see
- <http://www.gnu.org/licenses/>. */
-
-/* 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
-
-#include <sysdep.h>
-
-ENTRY_ALIGN (memcpy, 6)
-
- mov dst, dstin
- cmp count, #64
- b.ge L(cpy_not_short)
- cmp count, #15
- b.le L(tail15tiny)
-
- /* Deal with small copies quickly by dropping straight into the
- * exit block. */
-L(tail63):
- /* 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 L(tail15)
- 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]
-
-L(tail15):
- 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
-
-L(tail15tiny):
- /* 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
-
-L(cpy_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 L(tail63)
-2:
- subs count, count, #128
- b.ge L(cpy_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 L(tail63)
- 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
-L(cpy_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 L(tail63)
- RET
-END (memcpy)
-libc_hidden_builtin_def (memcpy)