--- /dev/null
+/*
+ * Copyright (C) 2013 ARM Ltd.
+ * Copyright (C) 2013 Linaro.
+ *
+ * This code is based on glibc cortex strings work originally authored by Linaro
+ * and re-licensed under GPLv2 for the Linux kernel. The original code can
+ * be found @
+ *
+ * http://bazaar.launchpad.net/~linaro-toolchain-dev/cortex-strings/trunk/
+ * files/head:/src/aarch64/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+/*
+ * Copy a buffer from src to dest (alignment handled by the hardware)
+ *
+ * Parameters:
+ * x0 - dest
+ * x1 - src
+ * x2 - n
+ * Returns:
+ * x0 - dest
+ */
+dstin .req x0
+src .req x1
+count .req x2
+tmp1 .req x3
+tmp1w .req w3
+tmp2 .req x4
+tmp2w .req w4
+dst .req x6
+
+A_l .req x7
+A_h .req x8
+B_l .req x9
+B_h .req x10
+C_l .req x11
+C_h .req x12
+D_l .req x13
+D_h .req x14
+
+ mov dst, dstin
+ cmp count, #16
+ /*When memory length is less than 16, the accessed are not aligned.*/
+ b.lo .Ltiny15
+
+ neg tmp2, src
+ ands tmp2, tmp2, #15/* Bytes to reach alignment. */
+ b.eq .LSrcAligned
+ sub count, count, tmp2
+ /*
+ * Copy the leading memory data from src to dst in an increasing
+ * address order.By this way,the risk of overwritting the source
+ * memory data is eliminated when the distance between src and
+ * dst is less than 16. The memory accesses here are alignment.
+ */
+ tbz tmp2, #0, 1f
+ ldrb1 tmp1w, src, #1
+ strb1 tmp1w, dst, #1
+1:
+ tbz tmp2, #1, 2f
+ ldrh1 tmp1w, src, #2
+ strh1 tmp1w, dst, #2
+2:
+ tbz tmp2, #2, 3f
+ ldr1 tmp1w, src, #4
+ str1 tmp1w, dst, #4
+3:
+ tbz tmp2, #3, .LSrcAligned
+ ldr1 tmp1, src, #8
+ str1 tmp1, dst, #8
+
+.LSrcAligned:
+ cmp count, #64
+ b.ge .Lcpy_over64
+ /*
+ * 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 .Ltiny15
+ cmp tmp1w, #0x20
+ b.eq 1f
+ b.lt 2f
+ ldp1 A_l, A_h, src, #16
+ stp1 A_l, A_h, dst, #16
+1:
+ ldp1 A_l, A_h, src, #16
+ stp1 A_l, A_h, dst, #16
+2:
+ ldp1 A_l, A_h, src, #16
+ stp1 A_l, A_h, dst, #16
+.Ltiny15:
+ /*
+ * Prefer to break one ldp/stp into several load/store to access
+ * memory in an increasing address order,rather than to load/store 16
+ * bytes from (src-16) to (dst-16) and to backward the src to aligned
+ * address,which way is used in original cortex memcpy. If keeping
+ * the original memcpy process here, memmove need to satisfy the
+ * precondition that src address is at least 16 bytes bigger than dst
+ * address,otherwise some source data will be overwritten when memove
+ * call memcpy directly. To make memmove simpler and decouple the
+ * memcpy's dependency on memmove, withdrew the original process.
+ */
+ tbz count, #3, 1f
+ ldr1 tmp1, src, #8
+ str1 tmp1, dst, #8
+1:
+ tbz count, #2, 2f
+ ldr1 tmp1w, src, #4
+ str1 tmp1w, dst, #4
+2:
+ tbz count, #1, 3f
+ ldrh1 tmp1w, src, #2
+ strh1 tmp1w, dst, #2
+3:
+ tbz count, #0, .Lexitfunc
+ ldrb1 tmp1w, src, #1
+ strb1 tmp1w, dst, #1
+
+ b .Lexitfunc
+
+.Lcpy_over64:
+ 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.
+ */
+ ldp1 A_l, A_h, src, #16
+ stp1 A_l, A_h, dst, #16
+ ldp1 B_l, B_h, src, #16
+ ldp1 C_l, C_h, src, #16
+ stp1 B_l, B_h, dst, #16
+ stp1 C_l, C_h, dst, #16
+ ldp1 D_l, D_h, src, #16
+ stp1 D_l, D_h, dst, #16
+
+ tst count, #0x3f
+ b.ne .Ltail63
+ b .Lexitfunc
+
+ /*
+ * Critical loop. Start at a new cache line boundary. Assuming
+ * 64 bytes per line this ensures the entire loop is in one line.
+ */
+ .p2align L1_CACHE_SHIFT
+.Lcpy_body_large:
+ /* pre-get 64 bytes data. */
+ ldp1 A_l, A_h, src, #16
+ ldp1 B_l, B_h, src, #16
+ ldp1 C_l, C_h, src, #16
+ ldp1 D_l, D_h, src, #16
+1:
+ /*
+ * interlace the load of next 64 bytes data block with store of the last
+ * loaded 64 bytes data.
+ */
+ stp1 A_l, A_h, dst, #16
+ ldp1 A_l, A_h, src, #16
+ stp1 B_l, B_h, dst, #16
+ ldp1 B_l, B_h, src, #16
+ stp1 C_l, C_h, dst, #16
+ ldp1 C_l, C_h, src, #16
+ stp1 D_l, D_h, dst, #16
+ ldp1 D_l, D_h, src, #16
+ subs count, count, #64
+ b.ge 1b
+ stp1 A_l, A_h, dst, #16
+ stp1 B_l, B_h, dst, #16
+ stp1 C_l, C_h, dst, #16
+ stp1 D_l, D_h, dst, #16
+
+ tst count, #0x3f
+ b.ne .Ltail63
+.Lexitfunc:
* Returns:
* x0 - dest
*/
-dstin .req x0
-src .req x1
-count .req x2
-tmp1 .req x3
-tmp1w .req w3
-tmp2 .req x4
-tmp2w .req w4
-tmp3 .req x5
-tmp3w .req w5
-dst .req x6
+ .macro ldrb1 ptr, regB, val
+ ldrb \ptr, [\regB], \val
+ .endm
-A_l .req x7
-A_h .req x8
-B_l .req x9
-B_h .req x10
-C_l .req x11
-C_h .req x12
-D_l .req x13
-D_h .req x14
+ .macro strb1 ptr, regB, val
+ strb \ptr, [\regB], \val
+ .endm
-ENTRY(memcpy)
- mov dst, dstin
- cmp count, #16
- /*When memory length is less than 16, the accessed are not aligned.*/
- b.lo .Ltiny15
+ .macro ldrh1 ptr, regB, val
+ ldrh \ptr, [\regB], \val
+ .endm
- neg tmp2, src
- ands tmp2, tmp2, #15/* Bytes to reach alignment. */
- b.eq .LSrcAligned
- sub count, count, tmp2
- /*
- * Copy the leading memory data from src to dst in an increasing
- * address order.By this way,the risk of overwritting the source
- * memory data is eliminated when the distance between src and
- * dst is less than 16. The memory accesses here are alignment.
- */
- tbz tmp2, #0, 1f
- ldrb tmp1w, [src], #1
- strb tmp1w, [dst], #1
-1:
- tbz tmp2, #1, 2f
- ldrh tmp1w, [src], #2
- strh tmp1w, [dst], #2
-2:
- tbz tmp2, #2, 3f
- ldr tmp1w, [src], #4
- str tmp1w, [dst], #4
-3:
- tbz tmp2, #3, .LSrcAligned
- ldr tmp1, [src],#8
- str tmp1, [dst],#8
+ .macro strh1 ptr, regB, val
+ strh \ptr, [\regB], \val
+ .endm
-.LSrcAligned:
- cmp count, #64
- b.ge .Lcpy_over64
- /*
- * 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 .Ltiny15
- cmp tmp1w, #0x20
- b.eq 1f
- b.lt 2f
- ldp A_l, A_h, [src], #16
- stp A_l, A_h, [dst], #16
-1:
- ldp A_l, A_h, [src], #16
- stp A_l, A_h, [dst], #16
-2:
- ldp A_l, A_h, [src], #16
- stp A_l, A_h, [dst], #16
-.Ltiny15:
- /*
- * Prefer to break one ldp/stp into several load/store to access
- * memory in an increasing address order,rather than to load/store 16
- * bytes from (src-16) to (dst-16) and to backward the src to aligned
- * address,which way is used in original cortex memcpy. If keeping
- * the original memcpy process here, memmove need to satisfy the
- * precondition that src address is at least 16 bytes bigger than dst
- * address,otherwise some source data will be overwritten when memove
- * call memcpy directly. To make memmove simpler and decouple the
- * memcpy's dependency on memmove, withdrew the original process.
- */
- tbz count, #3, 1f
- ldr tmp1, [src], #8
- str tmp1, [dst], #8
-1:
- tbz count, #2, 2f
- ldr tmp1w, [src], #4
- str tmp1w, [dst], #4
-2:
- tbz count, #1, 3f
- ldrh tmp1w, [src], #2
- strh tmp1w, [dst], #2
-3:
- tbz count, #0, .Lexitfunc
- ldrb tmp1w, [src]
- strb tmp1w, [dst]
+ .macro ldr1 ptr, regB, val
+ ldr \ptr, [\regB], \val
+ .endm
-.Lexitfunc:
- ret
+ .macro str1 ptr, regB, val
+ str \ptr, [\regB], \val
+ .endm
-.Lcpy_over64:
- 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],#16
- stp A_l, A_h, [dst],#16
- ldp B_l, B_h, [src],#16
- ldp C_l, C_h, [src],#16
- stp B_l, B_h, [dst],#16
- stp C_l, C_h, [dst],#16
- ldp D_l, D_h, [src],#16
- stp D_l, D_h, [dst],#16
+ .macro ldp1 ptr, regB, regC, val
+ ldp \ptr, \regB, [\regC], \val
+ .endm
- tst count, #0x3f
- b.ne .Ltail63
- ret
+ .macro stp1 ptr, regB, regC, val
+ stp \ptr, \regB, [\regC], \val
+ .endm
- /*
- * Critical loop. Start at a new cache line boundary. Assuming
- * 64 bytes per line this ensures the entire loop is in one line.
- */
- .p2align L1_CACHE_SHIFT
-.Lcpy_body_large:
- /* pre-get 64 bytes data. */
- ldp A_l, A_h, [src],#16
- ldp B_l, B_h, [src],#16
- ldp C_l, C_h, [src],#16
- ldp D_l, D_h, [src],#16
-1:
- /*
- * interlace the load of next 64 bytes data block with store of the last
- * loaded 64 bytes data.
- */
- stp A_l, A_h, [dst],#16
- ldp A_l, A_h, [src],#16
- stp B_l, B_h, [dst],#16
- ldp B_l, B_h, [src],#16
- stp C_l, C_h, [dst],#16
- ldp C_l, C_h, [src],#16
- stp D_l, D_h, [dst],#16
- ldp D_l, D_h, [src],#16
- subs count, count, #64
- b.ge 1b
- stp A_l, A_h, [dst],#16
- stp B_l, B_h, [dst],#16
- stp C_l, C_h, [dst],#16
- stp D_l, D_h, [dst],#16
-
- tst count, #0x3f
- b.ne .Ltail63
+ENTRY(memcpy)
+#include "copy_template.S"
ret
ENDPROC(memcpy)
projects / cascardo / linux.git / commitdiff