Merge branch 'tracking-cortex-strings-arm64' into merge-linux-linaro
diff --git a/arch/arm64/include/asm/string.h b/arch/arm64/include/asm/string.h
index 3ee8b30..64d2d48 100644
--- a/arch/arm64/include/asm/string.h
+++ b/arch/arm64/include/asm/string.h
@@ -22,6 +22,18 @@
#define __HAVE_ARCH_STRCHR
extern char *strchr(const char *, int c);
+#define __HAVE_ARCH_STRCMP
+extern int strcmp(const char *, const char *);
+
+#define __HAVE_ARCH_STRNCMP
+extern int strncmp(const char *, const char *, __kernel_size_t);
+
+#define __HAVE_ARCH_STRLEN
+extern __kernel_size_t strlen(const char *);
+
+#define __HAVE_ARCH_STRNLEN
+extern __kernel_size_t strnlen(const char *, __kernel_size_t);
+
#define __HAVE_ARCH_MEMCPY
extern void *memcpy(void *, const void *, __kernel_size_t);
@@ -34,4 +46,7 @@
#define __HAVE_ARCH_MEMSET
extern void *memset(void *, int, __kernel_size_t);
+#define __HAVE_ARCH_MEMCMP
+extern int memcmp(const void *, const void *, size_t);
+
#endif
diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c
index 338b568..1edc792 100644
--- a/arch/arm64/kernel/arm64ksyms.c
+++ b/arch/arm64/kernel/arm64ksyms.c
@@ -44,10 +44,15 @@
/* string / mem functions */
EXPORT_SYMBOL(strchr);
EXPORT_SYMBOL(strrchr);
+EXPORT_SYMBOL(strcmp);
+EXPORT_SYMBOL(strncmp);
+EXPORT_SYMBOL(strlen);
+EXPORT_SYMBOL(strnlen);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(memchr);
+EXPORT_SYMBOL(memcmp);
/* atomic bitops */
EXPORT_SYMBOL(set_bit);
diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
index 8f96db4..0d3407c 100644
--- a/arch/arm64/lib/Makefile
+++ b/arch/arm64/lib/Makefile
@@ -1,6 +1,7 @@
lib-y := bitops.o clear_user.o delay.o copy_from_user.o \
copy_to_user.o copy_in_user.o copy_page.o \
clear_page.o memchr.o memcpy.o memmove.o memset.o \
+ memcmp.o strcmp.o strncmp.o strlen.o strnlen.o \
strchr.o strrchr.o
ifeq ($(COMPILER),clang)
diff --git a/arch/arm64/lib/memcmp.S b/arch/arm64/lib/memcmp.S
new file mode 100644
index 0000000..c02a442
--- /dev/null
+++ b/arch/arm64/lib/memcmp.S
@@ -0,0 +1,258 @@
+/*
+ * 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/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+* compare memory areas(when two memory areas' offset are different,
+* alignment handled by the hardware)
+*
+* Parameters:
+* x0 - const memory area 1 pointer
+* x1 - const memory area 2 pointer
+* x2 - the maximal compare byte length
+* Returns:
+* x0 - a compare result, maybe less than, equal to, or greater than ZERO
+*/
+
+/* Parameters and result. */
+src1 .req x0
+src2 .req x1
+limit .req x2
+result .req x0
+
+/* Internal variables. */
+data1 .req x3
+data1w .req w3
+data2 .req x4
+data2w .req w4
+has_nul .req x5
+diff .req x6
+endloop .req x7
+tmp1 .req x8
+tmp2 .req x9
+tmp3 .req x10
+pos .req x11
+limit_wd .req x12
+mask .req x13
+
+ENTRY(memcmp)
+ cbz limit, .Lret0
+ eor tmp1, src1, src2
+ tst tmp1, #7
+ b.ne .Lmisaligned8
+ ands tmp1, src1, #7
+ b.ne .Lmutual_align
+ sub limit_wd, limit, #1 /* limit != 0, so no underflow. */
+ lsr limit_wd, limit_wd, #3 /* Convert to Dwords. */
+ /*
+ * The input source addresses are at alignment boundary.
+ * Directly compare eight bytes each time.
+ */
+.Lloop_aligned:
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+.Lstart_realigned:
+ subs limit_wd, limit_wd, #1
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ csinv endloop, diff, xzr, cs /* Last Dword or differences. */
+ cbz endloop, .Lloop_aligned
+
+ /* Not reached the limit, must have found a diff. */
+ tbz limit_wd, #63, .Lnot_limit
+
+ /* Limit % 8 == 0 => the diff is in the last 8 bytes. */
+ ands limit, limit, #7
+ b.eq .Lnot_limit
+ /*
+ * The remained bytes less than 8. It is needed to extract valid data
+ * from last eight bytes of the intended memory range.
+ */
+ lsl limit, limit, #3 /* bytes-> bits. */
+ mov mask, #~0
+CPU_BE( lsr mask, mask, limit )
+CPU_LE( lsl mask, mask, limit )
+ bic data1, data1, mask
+ bic data2, data2, mask
+
+ orr diff, diff, mask
+ b .Lnot_limit
+
+.Lmutual_align:
+ /*
+ * Sources are mutually aligned, but are not currently at an
+ * alignment boundary. Round down the addresses and then mask off
+ * the bytes that precede the start point.
+ */
+ bic src1, src1, #7
+ bic src2, src2, #7
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+ /*
+ * We can not add limit with tmp1 here.Since the addition probably
+ * make the limit overflown.
+ */
+ sub limit_wd, limit, #1/*limit != 0, so no underflow.*/
+ and tmp3, limit_wd, #7
+ lsr limit_wd, limit_wd, #3
+ add tmp3, tmp3, tmp1
+ add limit_wd, limit_wd, tmp3, lsr #3
+ add limit, limit, tmp1/* Adjust the limit for the extra. */
+
+ lsl tmp1, tmp1, #3/* Bytes beyond alignment -> bits.*/
+ neg tmp1, tmp1/* Bits to alignment -64. */
+ mov tmp2, #~0
+ /*mask off the non-intended bytes before the start address.*/
+CPU_BE( lsl tmp2, tmp2, tmp1 )/*Big-endian.Early bytes are at MSB*/
+ /* Little-endian. Early bytes are at LSB. */
+CPU_LE( lsr tmp2, tmp2, tmp1 )
+
+ orr data1, data1, tmp2
+ orr data2, data2, tmp2
+ b .Lstart_realigned
+
+ /*src1 and src2 have different alignment offset.*/
+.Lmisaligned8:
+ cmp limit, #8
+ b.lo .Ltiny8proc /*limit < 8: compare byte by byte*/
+
+ and tmp1, src1, #7
+ neg tmp1, tmp1
+ add tmp1, tmp1, #8/*valid length in the first 8 bytes of src1*/
+ and tmp2, src2, #7
+ neg tmp2, tmp2
+ add tmp2, tmp2, #8/*valid length in the first 8 bytes of src2*/
+ subs tmp3, tmp1, tmp2
+ csel pos, tmp1, tmp2, hi /*Choose the maximum.*/
+
+ sub limit, limit, pos
+ /*compare the proceeding bytes in the first 8 byte segment.*/
+.Ltinycmp:
+ ldrb data1w, [src1], #1
+ ldrb data2w, [src2], #1
+ subs pos, pos, #1
+ ccmp data1w, data2w, #0, ne /* NZCV = 0b0000. */
+ b.eq .Ltinycmp
+ cbnz pos, 1f /*diff occurred before the last byte.*/
+ cmp data1w, data2w
+ b.eq .Lstart_align
+1:
+ sub result, data1, data2
+ ret
+
+.Lstart_align:
+ lsr limit_wd, limit, #3
+ cbz limit_wd, .Lremain8
+
+ ands xzr, src1, #7
+ b.eq .Lrecal_offset
+ /*process more leading bytes to make src1 aligned...*/
+ add src1, src1, tmp3 /*backwards src1 to alignment boundary*/
+ add src2, src2, tmp3
+ sub limit, limit, tmp3
+ lsr limit_wd, limit, #3
+ cbz limit_wd, .Lremain8
+ /*load 8 bytes from aligned SRC1..*/
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+
+ subs limit_wd, limit_wd, #1
+ eor diff, data1, data2 /*Non-zero if differences found.*/
+ csinv endloop, diff, xzr, ne
+ cbnz endloop, .Lunequal_proc
+ /*How far is the current SRC2 from the alignment boundary...*/
+ and tmp3, tmp3, #7
+
+.Lrecal_offset:/*src1 is aligned now..*/
+ neg pos, tmp3
+.Lloopcmp_proc:
+ /*
+ * Divide the eight bytes into two parts. First,backwards the src2
+ * to an alignment boundary,load eight bytes and compare from
+ * the SRC2 alignment boundary. If all 8 bytes are equal,then start
+ * the second part's comparison. Otherwise finish the comparison.
+ * This special handle can garantee all the accesses are in the
+ * thread/task space...
+ */
+ ldr data1, [src1,pos]
+ ldr data2, [src2,pos]
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ cbnz diff, .Lnot_limit
+
+ /*The second part process*/
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ subs limit_wd, limit_wd, #1
+ csinv endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+ cbz endloop, .Lloopcmp_proc
+.Lunequal_proc:
+ cbz diff, .Lremain8
+
+/*There is diff occured in the latest comparison.*/
+.Lnot_limit:
+/*
+* For little endian,reverse the low significant equal bits into MSB,then
+* following CLZ can find how many equal bits exist.
+*/
+CPU_LE( rev diff, diff )
+CPU_LE( rev data1, data1 )
+CPU_LE( rev data2, data2 )
+
+ /*
+ * The MS-non-zero bit of DIFF marks either the first bit
+ * that is different, or the end of the significant data.
+ * Shifting left now will bring the critical information into the
+ * top bits.
+ */
+ clz pos, diff
+ lsl data1, data1, pos
+ lsl data2, data2, pos
+ /*
+ * We need to zero-extend (char is unsigned) the value and then
+ * perform a signed subtraction.
+ */
+ lsr data1, data1, #56
+ sub result, data1, data2, lsr #56
+ ret
+
+.Lremain8:
+ /* Limit % 8 == 0 =>. all data are equal.*/
+ ands limit, limit, #7
+ b.eq .Lret0
+
+.Ltiny8proc:
+ ldrb data1w, [src1], #1
+ ldrb data2w, [src2], #1
+ subs limit, limit, #1
+
+ ccmp data1w, data2w, #0, ne /* NZCV = 0b0000. */
+ b.eq .Ltiny8proc
+ sub result, data1, data2
+ ret
+.Lret0:
+ mov result, #0
+ ret
+ENDPROC(memcmp)
diff --git a/arch/arm64/lib/memcpy.S b/arch/arm64/lib/memcpy.S
index 27b5003..2f33230 100644
--- a/arch/arm64/lib/memcpy.S
+++ b/arch/arm64/lib/memcpy.S
@@ -1,5 +1,13 @@
/*
* 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
@@ -27,27 +35,164 @@
* 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
+
+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
+
ENTRY(memcpy)
- mov x4, x0
- subs x2, x2, #8
- b.mi 2f
-1: ldr x3, [x1], #8
- subs x2, x2, #8
- str x3, [x4], #8
- b.pl 1b
-2: adds x2, x2, #4
- b.mi 3f
- ldr w3, [x1], #4
- sub x2, x2, #4
- str w3, [x4], #4
-3: adds x2, x2, #2
- b.mi 4f
- ldrh w3, [x1], #2
- sub x2, x2, #2
- strh w3, [x4], #2
-4: adds x2, x2, #1
- b.mi 5f
- ldrb w3, [x1]
- strb w3, [x4]
-5: ret
+ 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 not 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
+
+.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:
+ /*
+ * To make memmove simpler, we prefer to break one ldp/stp into
+ * several load/store to access memory in an increasing address order,
+ * rather than load/store 16 bytes just as the old cortex memcpy.
+ * The process in original cortex need to satisfy the procondition
+ * that the src address is at least 16 bytes bigger than dst address,
+ * otherwise some source data will be overwritten.
+ */
+ 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]
+
+.Lexitfunc:
+ ret
+
+.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
+
+ tst count, #0x3f
+ 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:
+ /* 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
+ ret
ENDPROC(memcpy)
diff --git a/arch/arm64/lib/memmove.S b/arch/arm64/lib/memmove.S
index b79fdfa..5a0a440 100644
--- a/arch/arm64/lib/memmove.S
+++ b/arch/arm64/lib/memmove.S
@@ -1,5 +1,13 @@
/*
* 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
@@ -28,30 +36,161 @@
* 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
+
+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
+
ENTRY(memmove)
- cmp x0, x1
- b.ls memcpy
- add x4, x0, x2
- add x1, x1, x2
- subs x2, x2, #8
- b.mi 2f
-1: ldr x3, [x1, #-8]!
- subs x2, x2, #8
- str x3, [x4, #-8]!
- b.pl 1b
-2: adds x2, x2, #4
- b.mi 3f
- ldr w3, [x1, #-4]!
- sub x2, x2, #4
- str w3, [x4, #-4]!
-3: adds x2, x2, #2
- b.mi 4f
- ldrh w3, [x1, #-2]!
- sub x2, x2, #2
- strh w3, [x4, #-2]!
-4: adds x2, x2, #1
- b.mi 5f
- ldrb w3, [x1, #-1]
- strb w3, [x4, #-1]
-5: ret
+ cmp dstin, src
+ b.lo memcpy
+ add tmp1, src, count
+ cmp dstin, tmp1
+ b.hs memcpy /* No overlap. */
+
+ add dst, dstin, count
+ add src, src, count
+ cmp count, #16
+ b.lo .Ltail15 /*probably non-alignment accesses.*/
+
+ ands tmp2, src, #15 /* Bytes to reach alignment. */
+ b.eq .LSrcAligned
+ sub count, count, tmp2
+ /*
+ * process the aligned offset length to make the src aligned firstly.
+ * those extra instructions' cost is acceptable. It also make the
+ * coming accesses are based on aligned address.
+ */
+ 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]!
+
+.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 .Ltail15
+ 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]!
+
+.Ltail15:
+ 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, #-1]
+ strb tmp1w, [dst, #-1]
+
+.Lexitfunc:
+ ret
+
+.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, #-32]
+ ldp C_l, C_h, [src, #-48]
+ stp B_l, B_h, [dst, #-32]
+ stp C_l, C_h, [dst, #-48]
+ ldp D_l, D_h, [src, #-64]!
+ stp D_l, D_h, [dst, #-64]!
+
+ tst count, #0x3f
+ 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:
+ /* pre-load 64 bytes data. */
+ ldp A_l, A_h, [src, #-16]
+ ldp B_l, B_h, [src, #-32]
+ ldp C_l, C_h, [src, #-48]
+ ldp D_l, D_h, [src, #-64]!
+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, #-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]!
+
+ tst count, #0x3f
+ b.ne .Ltail63
+ ret
ENDPROC(memmove)
diff --git a/arch/arm64/lib/memset.S b/arch/arm64/lib/memset.S
index 87e4a68..e02f5fa 100644
--- a/arch/arm64/lib/memset.S
+++ b/arch/arm64/lib/memset.S
@@ -1,5 +1,13 @@
/*
* 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
@@ -27,27 +35,181 @@
* Returns:
* x0 - buf
*/
+
+dstin .req x0
+val .req w1
+count .req x2
+tmp1 .req x3
+tmp1w .req w3
+tmp2 .req x4
+tmp2w .req w4
+zva_len_x .req x5
+zva_len .req w5
+zva_bits_x .req x6
+
+A_l .req x7
+A_lw .req w7
+dst .req x8
+tmp3w .req w9
+tmp3 .req x9
+
ENTRY(memset)
- mov x4, x0
- and w1, w1, #0xff
- orr w1, w1, w1, lsl #8
- orr w1, w1, w1, lsl #16
- orr x1, x1, x1, lsl #32
- subs x2, x2, #8
- b.mi 2f
-1: str x1, [x4], #8
- subs x2, x2, #8
- b.pl 1b
-2: adds x2, x2, #4
- b.mi 3f
- sub x2, x2, #4
- str w1, [x4], #4
-3: adds x2, x2, #2
- b.mi 4f
- sub x2, x2, #2
- strh w1, [x4], #2
-4: adds x2, x2, #1
- b.mi 5f
- strb w1, [x4]
-5: ret
+ mov dst, dstin /* Preserve return value. */
+ and A_lw, val, #255
+ orr A_lw, A_lw, A_lw, lsl #8
+ orr A_lw, A_lw, A_lw, lsl #16
+ orr A_l, A_l, A_l, lsl #32
+
+ cmp count, #15
+ b.hi .Lover16_proc
+ /*All store maybe are non-aligned..*/
+ tbz count, #3, 1f
+ str A_l, [dst], #8
+1:
+ tbz count, #2, 2f
+ str A_lw, [dst], #4
+2:
+ tbz count, #1, 3f
+ strh A_lw, [dst], #2
+3:
+ tbz count, #0, 4f
+ strb A_lw, [dst]
+4:
+ ret
+
+.Lover16_proc:
+ /*Whether the start address is with 16.*/
+ neg tmp2, dst
+ ands tmp2, tmp2, #15
+ b.eq .Laligned
+/*
+* The count is not less than 16, we can use stp to store the start 16 bytes,
+* then adjust the dst aligned with 16.This process will make the current
+* memory address at alignment boundary now.
+*/
+ stp A_l, A_l, [dst] /*non-aligned store..*/
+ /*make the dst aligned..*/
+ sub count, count, tmp2
+ add dst, dst, tmp2
+
+.Laligned:
+ cbz A_l, .Lzero_mem
+
+.Ltail_maybe_long:
+ cmp count, #64
+ b.ge .Lnot_short
+.Ltail63:
+ ands tmp1, count, #0x30
+ b.eq 3f
+ cmp tmp1w, #0x20
+ b.eq 1f
+ b.lt 2f
+ stp A_l, A_l, [dst], #16
+1:
+ stp A_l, A_l, [dst], #16
+2:
+ stp A_l, A_l, [dst], #16
+/*
+* The last store length is less than 16,use stp to write last 16 bytes.
+* It will lead some bytes written twice and the access is non-aligned.
+*/
+3:
+ ands count, count, #15
+ cbz count, 4f
+ add dst, dst, count
+ stp A_l, A_l, [dst, #-16] /* Repeat some/all of last store. */
+4:
+ 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
+.Lnot_short:
+ sub dst, dst, #16/* Pre-bias. */
+ sub count, count, #64
+1:
+ stp A_l, A_l, [dst, #16]
+ stp A_l, A_l, [dst, #32]
+ stp A_l, A_l, [dst, #48]
+ stp A_l, A_l, [dst, #64]!
+ subs count, count, #64
+ b.ge 1b
+ tst count, #0x3f
+ add dst, dst, #16
+ b.ne .Ltail63
+.Lexitfunc:
+ ret
+
+ /*
+ * For zeroing memory, check to see if we can use the ZVA feature to
+ * zero entire 'cache' lines.
+ */
+.Lzero_mem:
+ cmp count, #63
+ b.le .Ltail63
+ /*
+ * For zeroing small amounts of memory, it's not worth setting up
+ * the line-clear code.
+ */
+ cmp count, #128
+ b.lt .Lnot_short /*count is at least 128 bytes*/
+
+ mrs tmp1, dczid_el0
+ tbnz tmp1, #4, .Lnot_short
+ mov tmp3w, #4
+ and zva_len, tmp1w, #15 /* Safety: other bits reserved. */
+ lsl zva_len, tmp3w, zva_len
+
+ ands tmp3w, zva_len, #63
+ /*
+ * ensure the zva_len is not less than 64.
+ * It is not meaningful to use ZVA if the block size is less than 64.
+ */
+ b.ne .Lnot_short
+.Lzero_by_line:
+ /*
+ * Compute how far we need to go to become suitably aligned. We're
+ * already at quad-word alignment.
+ */
+ cmp count, zva_len_x
+ b.lt .Lnot_short /* Not enough to reach alignment. */
+ sub zva_bits_x, zva_len_x, #1
+ neg tmp2, dst
+ ands tmp2, tmp2, zva_bits_x
+ b.eq 2f /* Already aligned. */
+ /* Not aligned, check that there's enough to copy after alignment.*/
+ sub tmp1, count, tmp2
+ /*
+ * grantee the remain length to be ZVA is bigger than 64,
+ * avoid to make the 2f's process over mem range.*/
+ cmp tmp1, #64
+ ccmp tmp1, zva_len_x, #8, ge /* NZCV=0b1000 */
+ b.lt .Lnot_short
+ /*
+ * We know that there's at least 64 bytes to zero and that it's safe
+ * to overrun by 64 bytes.
+ */
+ mov count, tmp1
+1:
+ stp A_l, A_l, [dst]
+ stp A_l, A_l, [dst, #16]
+ stp A_l, A_l, [dst, #32]
+ subs tmp2, tmp2, #64
+ stp A_l, A_l, [dst, #48]
+ add dst, dst, #64
+ b.ge 1b
+ /* We've overrun a bit, so adjust dst downwards.*/
+ add dst, dst, tmp2
+2:
+ sub count, count, zva_len_x
+3:
+ dc zva, dst
+ add dst, dst, zva_len_x
+ subs count, count, zva_len_x
+ b.ge 3b
+ ands count, count, zva_bits_x
+ b.ne .Ltail_maybe_long
+ ret
ENDPROC(memset)
diff --git a/arch/arm64/lib/strcmp.S b/arch/arm64/lib/strcmp.S
new file mode 100644
index 0000000..f50b8f0
--- /dev/null
+++ b/arch/arm64/lib/strcmp.S
@@ -0,0 +1,234 @@
+/*
+ * 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/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * compare two strings
+ *
+ * Parameters:
+ * x0 - const string 1 pointer
+ * x1 - const string 2 pointer
+ * Returns:
+ * x0 - an integer less than, equal to, or greater than zero
+ * if s1 is found, respectively, to be less than, to match,
+ * or be greater than s2.
+ */
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+/* Parameters and result. */
+src1 .req x0
+src2 .req x1
+result .req x0
+
+/* Internal variables. */
+data1 .req x2
+data1w .req w2
+data2 .req x3
+data2w .req w3
+has_nul .req x4
+diff .req x5
+syndrome .req x6
+tmp1 .req x7
+tmp2 .req x8
+tmp3 .req x9
+zeroones .req x10
+pos .req x11
+
+ENTRY(strcmp)
+ eor tmp1, src1, src2
+ mov zeroones, #REP8_01
+ tst tmp1, #7
+ b.ne .Lmisaligned8
+ ands tmp1, src1, #7
+ b.ne .Lmutual_align
+
+ /*
+ * NUL detection works on the principle that (X - 1) & (~X) & 0x80
+ * (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+ * can be done in parallel across the entire word.
+ */
+.Lloop_aligned:
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+.Lstart_realigned:
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ bic has_nul, tmp1, tmp2 /* Non-zero if NUL terminator. */
+ orr syndrome, diff, has_nul
+ cbz syndrome, .Lloop_aligned
+ b .Lcal_cmpresult
+
+.Lmutual_align:
+ /*
+ * Sources are mutually aligned, but are not currently at an
+ * alignment boundary. Round down the addresses and then mask off
+ * the bytes that preceed the start point.
+ */
+ bic src1, src1, #7
+ bic src2, src2, #7
+ lsl tmp1, tmp1, #3 /* Bytes beyond alignment -> bits. */
+ ldr data1, [src1], #8
+ neg tmp1, tmp1 /* Bits to alignment -64. */
+ ldr data2, [src2], #8
+ mov tmp2, #~0
+ /* Big-endian. Early bytes are at MSB. */
+CPU_BE( lsl tmp2, tmp2, tmp1 ) /* Shift (tmp1 & 63). */
+ /* Little-endian. Early bytes are at LSB. */
+CPU_LE( lsr tmp2, tmp2, tmp1 ) /* Shift (tmp1 & 63). */
+
+ orr data1, data1, tmp2
+ orr data2, data2, tmp2
+ b .Lstart_realigned
+
+.Lmisaligned8:
+ /*
+ * Get the align offset length to compare per byte first.
+ * After this process, one string's address will be aligned.
+ */
+ and tmp1, src1, #7
+ neg tmp1, tmp1
+ add tmp1, tmp1, #8
+ and tmp2, src2, #7
+ neg tmp2, tmp2
+ add tmp2, tmp2, #8
+ subs tmp3, tmp1, tmp2
+ csel pos, tmp1, tmp2, hi /*Choose the maximum. */
+.Ltinycmp:
+ ldrb data1w, [src1], #1
+ ldrb data2w, [src2], #1
+ subs pos, pos, #1
+ ccmp data1w, #1, #0, ne /* NZCV = 0b0000. */
+ ccmp data1w, data2w, #0, cs /* NZCV = 0b0000. */
+ b.eq .Ltinycmp
+ cbnz pos, 1f /*find the null or unequal...*/
+ cmp data1w, #1
+ ccmp data1w, data2w, #0, cs
+ b.eq .Lstart_align /*the last bytes are equal....*/
+1:
+ sub result, data1, data2
+ ret
+
+.Lstart_align:
+ ands xzr, src1, #7
+ b.eq .Lrecal_offset
+ /*process more leading bytes to make str1 aligned...*/
+ add src1, src1, tmp3
+ add src2, src2, tmp3
+ /*load 8 bytes from aligned str1 and non-aligned str2..*/
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ bic has_nul, tmp1, tmp2
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ orr syndrome, diff, has_nul
+ cbnz syndrome, .Lcal_cmpresult
+ /*How far is the current str2 from the alignment boundary...*/
+ and tmp3, tmp3, #7
+.Lrecal_offset:
+ neg pos, tmp3
+.Lloopcmp_proc:
+ /*
+ * Divide the eight bytes into two parts. First,backwards the src2
+ * to an alignment boundary,load eight bytes from the SRC2 alignment
+ * boundary,then compare with the relative bytes from SRC1.
+ * If all 8 bytes are equal,then start the second part's comparison.
+ * Otherwise finish the comparison.
+ * This special handle can garantee all the accesses are in the
+ * thread/task space.
+ */
+ ldr data1, [src1,pos]
+ ldr data2, [src2,pos]
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ bic has_nul, tmp1, tmp2
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ orr syndrome, diff, has_nul
+ cbnz syndrome, .Lcal_cmpresult
+
+ /*The second part process*/
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ bic has_nul, tmp1, tmp2
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ orr syndrome, diff, has_nul
+ cbz syndrome, .Lloopcmp_proc
+
+.Lcal_cmpresult:
+ /*
+ * reversed the byte-order as big-endian,then CLZ can find the most
+ * significant zero bits.
+ */
+CPU_LE( rev syndrome, syndrome )
+CPU_LE( rev data1, data1 )
+CPU_LE( rev data2, data2 )
+
+ /*
+ * For big-endian we cannot use the trick with the syndrome value
+ * as carry-propagation can corrupt the upper bits if the trailing
+ * bytes in the string contain 0x01.
+ * However, if there is no NUL byte in the dword, we can generate
+ * the result directly. We ca not just subtract the bytes as the
+ * MSB might be significant.
+ */
+CPU_BE( cbnz has_nul, 1f )
+CPU_BE( cmp data1, data2 )
+CPU_BE( cset result, ne )
+CPU_BE( cneg result, result, lo )
+CPU_BE( ret )
+CPU_BE( 1: )
+ /*Re-compute the NUL-byte detection, using a byte-reversed value. */
+CPU_BE( rev tmp3, data1 )
+CPU_BE( sub tmp1, tmp3, zeroones )
+CPU_BE( orr tmp2, tmp3, #REP8_7f )
+CPU_BE( bic has_nul, tmp1, tmp2 )
+CPU_BE( rev has_nul, has_nul )
+CPU_BE( orr syndrome, diff, has_nul )
+
+ clz pos, syndrome
+ /*
+ * The MS-non-zero bit of the syndrome marks either the first bit
+ * that is different, or the top bit of the first zero byte.
+ * Shifting left now will bring the critical information into the
+ * top bits.
+ */
+ lsl data1, data1, pos
+ lsl data2, data2, pos
+ /*
+ * But we need to zero-extend (char is unsigned) the value and then
+ * perform a signed 32-bit subtraction.
+ */
+ lsr data1, data1, #56
+ sub result, data1, data2, lsr #56
+ ret
+ENDPROC(strcmp)
diff --git a/arch/arm64/lib/strlen.S b/arch/arm64/lib/strlen.S
new file mode 100644
index 0000000..987b68b
--- /dev/null
+++ b/arch/arm64/lib/strlen.S
@@ -0,0 +1,126 @@
+/*
+ * 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/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * calculate the length of a string
+ *
+ * Parameters:
+ * x0 - const string pointer
+ * Returns:
+ * x0 - the return length of specific string
+ */
+
+/* Arguments and results. */
+srcin .req x0
+len .req x0
+
+/* Locals and temporaries. */
+src .req x1
+data1 .req x2
+data2 .req x3
+data2a .req x4
+has_nul1 .req x5
+has_nul2 .req x6
+tmp1 .req x7
+tmp2 .req x8
+tmp3 .req x9
+tmp4 .req x10
+zeroones .req x11
+pos .req x12
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+ENTRY(strlen)
+ mov zeroones, #REP8_01
+ bic src, srcin, #15
+ ands tmp1, srcin, #15
+ b.ne .Lmisaligned
+ /*
+ * NUL detection works on the principle that (X - 1) & (~X) & 0x80
+ * (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+ * can be done in parallel across the entire word.
+ */
+ /*
+ * The inner loop deals with two Dwords at a time. This has a
+ * slightly higher start-up cost, but we should win quite quickly,
+ * especially on cores with a high number of issue slots per
+ * cycle, as we get much better parallelism out of the operations.
+ */
+.Lloop:
+ ldp data1, data2, [src], #16
+.Lrealigned:
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ sub tmp3, data2, zeroones
+ orr tmp4, data2, #REP8_7f
+ bic has_nul1, tmp1, tmp2
+ bics has_nul2, tmp3, tmp4
+ ccmp has_nul1, #0, #0, eq /* NZCV = 0000 */
+ b.eq .Lloop
+
+ sub len, src, srcin
+ cbz has_nul1, .Lnul_in_data2
+CPU_BE( mov data2, data1 ) /*prepare data to re-calculate the syndrome*/
+ sub len, len, #8
+ mov has_nul2, has_nul1
+.Lnul_in_data2:
+ /*
+ * For big-endian, carry propagation (if the final byte in the
+ * string is 0x01) means we cannot use has_nul directly. The
+ * easiest way to get the correct byte is to byte-swap the data
+ * and calculate the syndrome a second time.
+ */
+CPU_BE( rev data2, data2 )
+CPU_BE( sub tmp1, data2, zeroones )
+CPU_BE( orr tmp2, data2, #REP8_7f )
+CPU_BE( bic has_nul2, tmp1, tmp2 )
+
+ sub len, len, #8
+ rev has_nul2, has_nul2
+ clz pos, has_nul2
+ add len, len, pos, lsr #3 /* Bits to bytes. */
+ ret
+
+.Lmisaligned:
+ cmp tmp1, #8
+ neg tmp1, tmp1
+ ldp data1, data2, [src], #16
+ lsl tmp1, tmp1, #3 /* Bytes beyond alignment -> bits. */
+ mov tmp2, #~0
+ /* Big-endian. Early bytes are at MSB. */
+CPU_BE( lsl tmp2, tmp2, tmp1 ) /* Shift (tmp1 & 63). */
+ /* Little-endian. Early bytes are at LSB. */
+CPU_LE( lsr tmp2, tmp2, tmp1 ) /* Shift (tmp1 & 63). */
+
+ orr data1, data1, tmp2
+ orr data2a, data2, tmp2
+ csinv data1, data1, xzr, le
+ csel data2, data2, data2a, le
+ b .Lrealigned
+ENDPROC(strlen)
diff --git a/arch/arm64/lib/strncmp.S b/arch/arm64/lib/strncmp.S
new file mode 100644
index 0000000..81c8441
--- /dev/null
+++ b/arch/arm64/lib/strncmp.S
@@ -0,0 +1,310 @@
+/*
+ * 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/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * compare two strings
+ *
+ * Parameters:
+ * x0 - const string 1 pointer
+ * x1 - const string 2 pointer
+ * x2 - the maximal length to be compared
+ * Returns:
+ * x0 - an integer less than, equal to, or greater than zero if s1 is found,
+ * respectively, to be less than, to match, or be greater than s2.
+ */
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+/* Parameters and result. */
+src1 .req x0
+src2 .req x1
+limit .req x2
+result .req x0
+
+/* Internal variables. */
+data1 .req x3
+data1w .req w3
+data2 .req x4
+data2w .req w4
+has_nul .req x5
+diff .req x6
+syndrome .req x7
+tmp1 .req x8
+tmp2 .req x9
+tmp3 .req x10
+zeroones .req x11
+pos .req x12
+limit_wd .req x13
+mask .req x14
+endloop .req x15
+
+ENTRY(strncmp)
+ cbz limit, .Lret0
+ eor tmp1, src1, src2
+ mov zeroones, #REP8_01
+ tst tmp1, #7
+ b.ne .Lmisaligned8
+ ands tmp1, src1, #7
+ b.ne .Lmutual_align
+ /* Calculate the number of full and partial words -1. */
+ /*
+ * when limit is mulitply of 8, if not sub 1,
+ * the judgement of last dword will wrong.
+ */
+ sub limit_wd, limit, #1 /* limit != 0, so no underflow. */
+ lsr limit_wd, limit_wd, #3 /* Convert to Dwords. */
+
+ /*
+ * NUL detection works on the principle that (X - 1) & (~X) & 0x80
+ * (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+ * can be done in parallel across the entire word.
+ */
+.Lloop_aligned:
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+.Lstart_realigned:
+ subs limit_wd, limit_wd, #1
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ csinv endloop, diff, xzr, pl /* Last Dword or differences.*/
+ bics has_nul, tmp1, tmp2 /* Non-zero if NUL terminator. */
+ ccmp endloop, #0, #0, eq
+ b.eq .Lloop_aligned
+
+ /*Not reached the limit, must have found the end or a diff. */
+ tbz limit_wd, #63, .Lnot_limit
+
+ /* Limit % 8 == 0 => all bytes significant. */
+ ands limit, limit, #7
+ b.eq .Lnot_limit
+
+ lsl limit, limit, #3 /* Bits -> bytes. */
+ mov mask, #~0
+CPU_BE( lsr mask, mask, limit )
+CPU_LE( lsl mask, mask, limit )
+ bic data1, data1, mask
+ bic data2, data2, mask
+
+ /* Make sure that the NUL byte is marked in the syndrome. */
+ orr has_nul, has_nul, mask
+
+.Lnot_limit:
+ orr syndrome, diff, has_nul
+ b .Lcal_cmpresult
+
+.Lmutual_align:
+ /*
+ * Sources are mutually aligned, but are not currently at an
+ * alignment boundary. Round down the addresses and then mask off
+ * the bytes that precede the start point.
+ * We also need to adjust the limit calculations, but without
+ * overflowing if the limit is near ULONG_MAX.
+ */
+ bic src1, src1, #7
+ bic src2, src2, #7
+ ldr data1, [src1], #8
+ neg tmp3, tmp1, lsl #3 /* 64 - bits(bytes beyond align). */
+ ldr data2, [src2], #8
+ mov tmp2, #~0
+ sub limit_wd, limit, #1 /* limit != 0, so no underflow. */
+ /* Big-endian. Early bytes are at MSB. */
+CPU_BE( lsl tmp2, tmp2, tmp3 ) /* Shift (tmp1 & 63). */
+ /* Little-endian. Early bytes are at LSB. */
+CPU_LE( lsr tmp2, tmp2, tmp3 ) /* Shift (tmp1 & 63). */
+
+ and tmp3, limit_wd, #7
+ lsr limit_wd, limit_wd, #3
+ /* Adjust the limit. Only low 3 bits used, so overflow irrelevant.*/
+ add limit, limit, tmp1
+ add tmp3, tmp3, tmp1
+ orr data1, data1, tmp2
+ orr data2, data2, tmp2
+ add limit_wd, limit_wd, tmp3, lsr #3
+ b .Lstart_realigned
+
+/*when src1 offset is not equal to src2 offset...*/
+.Lmisaligned8:
+ cmp limit, #8
+ b.lo .Ltiny8proc /*limit < 8... */
+ /*
+ * Get the align offset length to compare per byte first.
+ * After this process, one string's address will be aligned.*/
+ and tmp1, src1, #7
+ neg tmp1, tmp1
+ add tmp1, tmp1, #8
+ and tmp2, src2, #7
+ neg tmp2, tmp2
+ add tmp2, tmp2, #8
+ subs tmp3, tmp1, tmp2
+ csel pos, tmp1, tmp2, hi /*Choose the maximum. */
+ /*
+ * Here, limit is not less than 8, so directly run .Ltinycmp
+ * without checking the limit.*/
+ sub limit, limit, pos
+.Ltinycmp:
+ ldrb data1w, [src1], #1
+ ldrb data2w, [src2], #1
+ subs pos, pos, #1
+ ccmp data1w, #1, #0, ne /* NZCV = 0b0000. */
+ ccmp data1w, data2w, #0, cs /* NZCV = 0b0000. */
+ b.eq .Ltinycmp
+ cbnz pos, 1f /*find the null or unequal...*/
+ cmp data1w, #1
+ ccmp data1w, data2w, #0, cs
+ b.eq .Lstart_align /*the last bytes are equal....*/
+1:
+ sub result, data1, data2
+ ret
+
+.Lstart_align:
+ lsr limit_wd, limit, #3
+ cbz limit_wd, .Lremain8
+ /*process more leading bytes to make str1 aligned...*/
+ ands xzr, src1, #7
+ b.eq .Lrecal_offset
+ add src1, src1, tmp3 /*tmp3 is positive in this branch.*/
+ add src2, src2, tmp3
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+
+ sub limit, limit, tmp3
+ lsr limit_wd, limit, #3
+ subs limit_wd, limit_wd, #1
+
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ csinv endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+ bics has_nul, tmp1, tmp2
+ ccmp endloop, #0, #0, eq /*has_null is ZERO: no null byte*/
+ b.ne .Lunequal_proc
+ /*How far is the current str2 from the alignment boundary...*/
+ and tmp3, tmp3, #7
+.Lrecal_offset:
+ neg pos, tmp3
+.Lloopcmp_proc:
+ /*
+ * Divide the eight bytes into two parts. First,backwards the src2
+ * to an alignment boundary,load eight bytes from the SRC2 alignment
+ * boundary,then compare with the relative bytes from SRC1.
+ * If all 8 bytes are equal,then start the second part's comparison.
+ * Otherwise finish the comparison.
+ * This special handle can garantee all the accesses are in the
+ * thread/task space.
+ */
+ ldr data1, [src1,pos]
+ ldr data2, [src2,pos]
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ bics has_nul, tmp1, tmp2 /* Non-zero if NUL terminator. */
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ csinv endloop, diff, xzr, eq
+ cbnz endloop, .Lunequal_proc
+
+ /*The second part process*/
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
+ subs limit_wd, limit_wd, #1
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ eor diff, data1, data2 /* Non-zero if differences found. */
+ csinv endloop, diff, xzr, ne/*if limit_wd is 0,will finish the cmp*/
+ bics has_nul, tmp1, tmp2
+ ccmp endloop, #0, #0, eq /*has_null is ZERO: no null byte*/
+ b.eq .Lloopcmp_proc
+
+.Lunequal_proc:
+ orr syndrome, diff, has_nul
+ cbz syndrome, .Lremain8
+.Lcal_cmpresult:
+ /*
+ * reversed the byte-order as big-endian,then CLZ can find the most
+ * significant zero bits.
+ */
+CPU_LE( rev syndrome, syndrome )
+CPU_LE( rev data1, data1 )
+CPU_LE( rev data2, data2 )
+ /*
+ * For big-endian we cannot use the trick with the syndrome value
+ * as carry-propagation can corrupt the upper bits if the trailing
+ * bytes in the string contain 0x01.
+ * However, if there is no NUL byte in the dword, we can generate
+ * the result directly. We can't just subtract the bytes as the
+ * MSB might be significant.
+ */
+CPU_BE( cbnz has_nul, 1f )
+CPU_BE( cmp data1, data2 )
+CPU_BE( cset result, ne )
+CPU_BE( cneg result, result, lo )
+CPU_BE( ret )
+CPU_BE( 1: )
+ /* Re-compute the NUL-byte detection, using a byte-reversed value.*/
+CPU_BE( rev tmp3, data1 )
+CPU_BE( sub tmp1, tmp3, zeroones )
+CPU_BE( orr tmp2, tmp3, #REP8_7f )
+CPU_BE( bic has_nul, tmp1, tmp2 )
+CPU_BE( rev has_nul, has_nul )
+CPU_BE( orr syndrome, diff, has_nul )
+ /*
+ * The MS-non-zero bit of the syndrome marks either the first bit
+ * that is different, or the top bit of the first zero byte.
+ * Shifting left now will bring the critical information into the
+ * top bits.
+ */
+ clz pos, syndrome
+ lsl data1, data1, pos
+ lsl data2, data2, pos
+ /*
+ * But we need to zero-extend (char is unsigned) the value and then
+ * perform a signed 32-bit subtraction.
+ */
+ lsr data1, data1, #56
+ sub result, data1, data2, lsr #56
+ ret
+
+.Lremain8:
+ /* Limit % 8 == 0 => all bytes significant. */
+ ands limit, limit, #7
+ b.eq .Lret0
+.Ltiny8proc:
+ ldrb data1w, [src1], #1
+ ldrb data2w, [src2], #1
+ subs limit, limit, #1
+
+ ccmp data1w, #1, #0, ne /* NZCV = 0b0000. */
+ ccmp data1w, data2w, #0, cs /* NZCV = 0b0000. */
+ b.eq .Ltiny8proc
+ sub result, data1, data2
+ ret
+
+.Lret0:
+ mov result, #0
+ ret
+ENDPROC(strncmp)
diff --git a/arch/arm64/lib/strnlen.S b/arch/arm64/lib/strnlen.S
new file mode 100644
index 0000000..2ca6657
--- /dev/null
+++ b/arch/arm64/lib/strnlen.S
@@ -0,0 +1,171 @@
+/*
+ * 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/>.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+/*
+ * determine the length of a fixed-size string
+ *
+ * Parameters:
+ * x0 - const string pointer
+ * x1 - maximal string length
+ * Returns:
+ * x0 - the return length of specific string
+ */
+
+/* Arguments and results. */
+srcin .req x0
+len .req x0
+limit .req x1
+
+/* Locals and temporaries. */
+src .req x2
+data1 .req x3
+data2 .req x4
+data2a .req x5
+has_nul1 .req x6
+has_nul2 .req x7
+tmp1 .req x8
+tmp2 .req x9
+tmp3 .req x10
+tmp4 .req x11
+zeroones .req x12
+pos .req x13
+limit_wd .req x14
+
+#define REP8_01 0x0101010101010101
+#define REP8_7f 0x7f7f7f7f7f7f7f7f
+#define REP8_80 0x8080808080808080
+
+ENTRY(strnlen)
+ cbz limit, .Lhit_limit
+ mov zeroones, #REP8_01
+ bic src, srcin, #15
+ ands tmp1, srcin, #15
+ b.ne .Lmisaligned
+ /* Calculate the number of full and partial words -1. */
+ sub limit_wd, limit, #1 /* Limit != 0, so no underflow. */
+ lsr limit_wd, limit_wd, #4 /* Convert to Qwords. */
+
+ /*
+ * NUL detection works on the principle that (X - 1) & (~X) & 0x80
+ * (=> (X - 1) & ~(X | 0x7f)) is non-zero iff a byte is zero, and
+ * can be done in parallel across the entire word.
+ */
+ /*
+ * The inner loop deals with two Dwords at a time. This has a
+ * slightly higher start-up cost, but we should win quite quickly,
+ * especially on cores with a high number of issue slots per
+ * cycle, as we get much better parallelism out of the operations.
+ */
+.Lloop:
+ ldp data1, data2, [src], #16
+.Lrealigned:
+ sub tmp1, data1, zeroones
+ orr tmp2, data1, #REP8_7f
+ sub tmp3, data2, zeroones
+ orr tmp4, data2, #REP8_7f
+ bic has_nul1, tmp1, tmp2
+ bic has_nul2, tmp3, tmp4
+ subs limit_wd, limit_wd, #1
+ orr tmp1, has_nul1, has_nul2
+ ccmp tmp1, #0, #0, pl /* NZCV = 0000 */
+ b.eq .Lloop
+
+ cbz tmp1, .Lhit_limit /* No null in final Qword. */
+
+ /*
+ * We know there's a null in the final Qword. The easiest thing
+ * to do now is work out the length of the string and return
+ * MIN (len, limit).
+ */
+ sub len, src, srcin
+ cbz has_nul1, .Lnul_in_data2
+CPU_BE( mov data2, data1 ) /*perpare data to re-calculate the syndrome*/
+
+ sub len, len, #8
+ mov has_nul2, has_nul1
+.Lnul_in_data2:
+ /*
+ * For big-endian, carry propagation (if the final byte in the
+ * string is 0x01) means we cannot use has_nul directly. The
+ * easiest way to get the correct byte is to byte-swap the data
+ * and calculate the syndrome a second time.
+ */
+CPU_BE( rev data2, data2 )
+CPU_BE( sub tmp1, data2, zeroones )
+CPU_BE( orr tmp2, data2, #REP8_7f )
+CPU_BE( bic has_nul2, tmp1, tmp2 )
+
+ sub len, len, #8
+ rev has_nul2, has_nul2
+ clz pos, has_nul2
+ add len, len, pos, lsr #3 /* Bits to bytes. */
+ cmp len, limit
+ csel len, len, limit, ls /* Return the lower value. */
+ ret
+
+.Lmisaligned:
+ /*
+ * Deal with a partial first word.
+ * We're doing two things in parallel here;
+ * 1) Calculate the number of words (but avoiding overflow if
+ * limit is near ULONG_MAX) - to do this we need to work out
+ * limit + tmp1 - 1 as a 65-bit value before shifting it;
+ * 2) Load and mask the initial data words - we force the bytes
+ * before the ones we are interested in to 0xff - this ensures
+ * early bytes will not hit any zero detection.
+ */
+ ldp data1, data2, [src], #16
+
+ sub limit_wd, limit, #1
+ and tmp3, limit_wd, #15
+ lsr limit_wd, limit_wd, #4
+
+ add tmp3, tmp3, tmp1
+ add limit_wd, limit_wd, tmp3, lsr #4
+
+ neg tmp4, tmp1
+ lsl tmp4, tmp4, #3 /* Bytes beyond alignment -> bits. */
+
+ mov tmp2, #~0
+ /* Big-endian. Early bytes are at MSB. */
+CPU_BE( lsl tmp2, tmp2, tmp4 ) /* Shift (tmp1 & 63). */
+ /* Little-endian. Early bytes are at LSB. */
+CPU_LE( lsr tmp2, tmp2, tmp4 ) /* Shift (tmp1 & 63). */
+
+ cmp tmp1, #8
+
+ orr data1, data1, tmp2
+ orr data2a, data2, tmp2
+
+ csinv data1, data1, xzr, le
+ csel data2, data2, data2a, le
+ b .Lrealigned
+
+.Lhit_limit:
+ mov len, limit
+ ret
+ENDPROC(strnlen)
