Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-19 10:31:48 +00:00
Code Issues Packages Projects Releases Wiki Activity
d5b9216fd5
linux/arch/sh/lib/memcpy-sh4.S
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license 
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

801 lines
15 KiB
ArmAsm
Raw Blame History

/* SPDX-License-Identifier: GPL-2.0 */
/*
* "memcpy" implementation of SuperH
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (c) 2002 STMicroelectronics Ltd
* Modified from memcpy.S and micro-optimised for SH4
* Stuart Menefy (stuart.menefy@st.com)
*
*/
#include <linux/linkage.h>
/*
* void *memcpy(void *dst, const void *src, size_t n);
*
* It is assumed that there is no overlap between src and dst.
* If there is an overlap, then the results are undefined.
*/
!
! GHIJ KLMN OPQR --> ...G HIJK LMNO PQR.
!
! Size is 16 or greater, and may have trailing bytes
.balign 32
.Lcase1:
! Read a long word and write a long word at once
! At the start of each iteration, r7 contains last long load
add #-1,r5 ! 79 EX
mov r4,r2 ! 5 MT (0 cycles latency)
mov.l @(r0,r5),r7 ! 21 LS (2 cycles latency)
add #-4,r5 ! 50 EX
add #7,r2 ! 79 EX
!
#ifdef CONFIG_CPU_LITTLE_ENDIAN
! 6 cycles, 4 bytes per iteration
3: mov.l @(r0,r5),r1 ! 21 LS (latency=2) ! NMLK
mov r7, r3 ! 5 MT (latency=0) ! RQPO
cmp/hi r2,r0 ! 57 MT
shll16 r3 ! 103 EX
mov r1,r6 ! 5 MT (latency=0)
shll8 r3 ! 102 EX ! Oxxx
shlr8 r6 ! 106 EX ! xNML
mov r1, r7 ! 5 MT (latency=0)
or r6,r3 ! 82 EX ! ONML
bt/s 3b ! 109 BR
mov.l r3,@-r0 ! 30 LS
#else
3: mov.l @(r0,r5),r1 ! 21 LS (latency=2) ! KLMN
mov r7,r3 ! 5 MT (latency=0) ! OPQR
cmp/hi r2,r0 ! 57 MT
shlr16 r3 ! 107 EX
shlr8 r3 ! 106 EX ! xxxO
mov r1,r6 ! 5 MT (latency=0)
shll8 r6 ! 102 EX ! LMNx
mov r1,r7 ! 5 MT (latency=0)
or r6,r3 ! 82 EX ! LMNO
bt/s 3b ! 109 BR
mov.l r3,@-r0 ! 30 LS
#endif
! Finally, copy a byte at once, if necessary
add #4,r5 ! 50 EX
cmp/eq r4,r0 ! 54 MT
add #-6,r2 ! 50 EX
bt 9f ! 109 BR
8: cmp/hi r2,r0 ! 57 MT
mov.b @(r0,r5),r1 ! 20 LS (latency=2)
bt/s 8b ! 109 BR
mov.b r1,@-r0 ! 29 LS
9: rts
nop
!
! GHIJ KLMN OPQR --> .GHI JKLM NOPQ R...
!
! Size is 16 or greater, and may have trailing bytes
.balign 32
.Lcase3:
! Read a long word and write a long word at once
! At the start of each iteration, r7 contains last long load
add #-3,r5 ! 79 EX
mov r4,r2 ! 5 MT (0 cycles latency)
mov.l @(r0,r5),r7 ! 21 LS (2 cycles latency)
add #-4,r5 ! 50 EX
add #7,r2 ! 79 EX
!
#ifdef CONFIG_CPU_LITTLE_ENDIAN
! 6 cycles, 4 bytes per iteration
3: mov.l @(r0,r5),r1 ! 21 LS (latency=2) ! NMLK
mov r7, r3 ! 5 MT (latency=0) ! RQPO
cmp/hi r2,r0 ! 57 MT
shll8 r3 ! 102 EX ! QPOx
mov r1,r6 ! 5 MT (latency=0)
shlr16 r6 ! 107 EX
shlr8 r6 ! 106 EX ! xxxN
mov r1, r7 ! 5 MT (latency=0)
or r6,r3 ! 82 EX ! QPON
bt/s 3b ! 109 BR
mov.l r3,@-r0 ! 30 LS
#else
3: mov r7,r3 ! OPQR
shlr8 r3 ! xOPQ
mov.l @(r0,r5),r7 ! KLMN
mov r7,r6
shll16 r6
shll8 r6 ! Nxxx
or r6,r3 ! NOPQ
cmp/hi r2,r0
bt/s 3b
mov.l r3,@-r0
#endif
! Finally, copy a byte at once, if necessary
add #6,r5 ! 50 EX
cmp/eq r4,r0 ! 54 MT
add #-6,r2 ! 50 EX
bt 9f ! 109 BR
8: cmp/hi r2,r0 ! 57 MT
mov.b @(r0,r5),r1 ! 20 LS (latency=2)
bt/s 8b ! 109 BR
mov.b r1,@-r0 ! 29 LS
9: rts
nop
ENTRY(memcpy)
! Calculate the invariants which will be used in the remainder
! of the code:
!
! r4 --> [ ... ] DST [ ... ] SRC
! [ ... ] [ ... ]
! : :
! r0 --> [ ... ] r0+r5 --> [ ... ]
!
!
! Short circuit the common case of src, dst and len being 32 bit aligned
! and test for zero length move
mov r6, r0 ! 5 MT (0 cycle latency)
or r4, r0 ! 82 EX
or r5, r0 ! 82 EX
tst r6, r6 ! 86 MT
bt/s 99f ! 111 BR (zero len)
tst #3, r0 ! 87 MT
mov r4, r0 ! 5 MT (0 cycle latency)
add r6, r0 ! 49 EX
mov #16, r1 ! 6 EX
bt/s .Lcase00 ! 111 BR (aligned)
sub r4, r5 ! 75 EX
! Arguments are not nicely long word aligned or zero len.
! Check for small copies, and if so do a simple byte at a time copy.
!
! Deciding on an exact value of 'small' is not easy, as the point at which
! using the optimised routines become worthwhile varies (these are the
! cycle counts for differnet sizes using byte-at-a-time vs. optimised):
! size byte-at-time long word byte
! 16 42 39-40 46-50 50-55
! 24 58 43-44 54-58 62-67
! 36 82 49-50 66-70 80-85
! However the penalty for getting it 'wrong' is much higher for long word
! aligned data (and this is more common), so use a value of 16.
cmp/gt r6,r1 ! 56 MT
add #-1,r5 ! 50 EX
bf/s 6f ! 108 BR (not small)
mov r5, r3 ! 5 MT (latency=0)
shlr r6 ! 104 EX
mov.b @(r0,r5),r1 ! 20 LS (latency=2)
bf/s 4f ! 111 BR
add #-1,r3 ! 50 EX
tst r6, r6 ! 86 MT
bt/s 98f ! 110 BR
mov.b r1,@-r0 ! 29 LS
! 4 cycles, 2 bytes per iteration
3: mov.b @(r0,r5),r1 ! 20 LS (latency=2)
4: mov.b @(r0,r3),r2 ! 20 LS (latency=2)
dt r6 ! 67 EX
mov.b r1,@-r0 ! 29 LS
bf/s 3b ! 111 BR
mov.b r2,@-r0 ! 29 LS
98:
rts
nop
99: rts
mov r4, r0
! Size is not small, so its worthwhile looking for optimisations.
! First align destination to a long word boundary.
!
! r5 = normal value -1
6: tst #3, r0 ! 87 MT
mov #3, r3 ! 6 EX
bt/s 2f ! 111 BR
and r0,r3 ! 78 EX
! 3 cycles, 1 byte per iteration
1: dt r3 ! 67 EX
mov.b @(r0,r5),r1 ! 19 LS (latency=2)
add #-1, r6 ! 79 EX
bf/s 1b ! 109 BR
mov.b r1,@-r0 ! 28 LS
2: add #1, r5 ! 79 EX
! Now select the appropriate bulk transfer code based on relative
! alignment of src and dst.
mov r0, r3 ! 5 MT (latency=0)
mov r5, r0 ! 5 MT (latency=0)
tst #1, r0 ! 87 MT
bf/s 1f ! 111 BR
mov #64, r7 ! 6 EX
! bit 0 clear
cmp/ge r7, r6 ! 55 MT
bt/s 2f ! 111 BR
tst #2, r0 ! 87 MT
! small
bt/s .Lcase0
mov r3, r0
bra .Lcase2
nop
! big
2: bt/s .Lcase0b
mov r3, r0
bra .Lcase2b
nop
! bit 0 set
1: tst #2, r0 ! 87 MT
bt/s .Lcase1
mov r3, r0
bra .Lcase3
nop
!
! GHIJ KLMN OPQR --> GHIJ KLMN OPQR
!
! src, dst and size are all long word aligned
! size is non-zero
.balign 32
.Lcase00:
mov #64, r1 ! 6 EX
mov r5, r3 ! 5 MT (latency=0)
cmp/gt r6, r1 ! 56 MT
add #-4, r5 ! 50 EX
bf .Lcase00b ! 108 BR (big loop)
shlr2 r6 ! 105 EX
shlr r6 ! 104 EX
mov.l @(r0, r5), r1 ! 21 LS (latency=2)
bf/s 4f ! 111 BR
add #-8, r3 ! 50 EX
tst r6, r6 ! 86 MT
bt/s 5f ! 110 BR
mov.l r1,@-r0 ! 30 LS
! 4 cycles, 2 long words per iteration
3: mov.l @(r0, r5), r1 ! 21 LS (latency=2)
4: mov.l @(r0, r3), r2 ! 21 LS (latency=2)
dt r6 ! 67 EX
mov.l r1, @-r0 ! 30 LS
bf/s 3b ! 109 BR
mov.l r2, @-r0 ! 30 LS
5: rts
nop
! Size is 16 or greater and less than 64, but may have trailing bytes
.balign 32
.Lcase0:
add #-4, r5 ! 50 EX
mov r4, r7 ! 5 MT (latency=0)
mov.l @(r0, r5), r1 ! 21 LS (latency=2)
mov #4, r2 ! 6 EX
add #11, r7 ! 50 EX
tst r2, r6 ! 86 MT
mov r5, r3 ! 5 MT (latency=0)
bt/s 4f ! 111 BR
add #-4, r3 ! 50 EX
mov.l r1,@-r0 ! 30 LS
! 4 cycles, 2 long words per iteration
3: mov.l @(r0, r5), r1 ! 21 LS (latency=2)
4: mov.l @(r0, r3), r2 ! 21 LS (latency=2)
cmp/hi r7, r0
mov.l r1, @-r0 ! 30 LS
bt/s 3b ! 109 BR
mov.l r2, @-r0 ! 30 LS
! Copy the final 0-3 bytes
add #3,r5 ! 50 EX
cmp/eq r0, r4 ! 54 MT
add #-10, r7 ! 50 EX
bt 9f ! 110 BR
! 3 cycles, 1 byte per iteration
1: mov.b @(r0,r5),r1 ! 19 LS
cmp/hi r7,r0 ! 57 MT
bt/s 1b ! 111 BR
mov.b r1,@-r0 ! 28 LS
9: rts
nop
! Size is at least 64 bytes, so will be going round the big loop at least once.
!
! r2 = rounded up r4
! r3 = rounded down r0
.balign 32
.Lcase0b:
add #-4, r5 ! 50 EX
.Lcase00b:
mov r0, r3 ! 5 MT (latency=0)
mov #(~0x1f), r1 ! 6 EX
and r1, r3 ! 78 EX
mov r4, r2 ! 5 MT (latency=0)
cmp/eq r3, r0 ! 54 MT
add #0x1f, r2 ! 50 EX
bt/s 1f ! 110 BR
and r1, r2 ! 78 EX
! copy initial words until cache line aligned
mov.l @(r0, r5), r1 ! 21 LS (latency=2)
tst #4, r0 ! 87 MT
mov r5, r6 ! 5 MT (latency=0)
add #-4, r6 ! 50 EX
bt/s 4f ! 111 BR
add #8, r3 ! 50 EX
tst #0x18, r0 ! 87 MT
bt/s 1f ! 109 BR
mov.l r1,@-r0 ! 30 LS
! 4 cycles, 2 long words per iteration
3: mov.l @(r0, r5), r1 ! 21 LS (latency=2)
4: mov.l @(r0, r6), r7 ! 21 LS (latency=2)
cmp/eq r3, r0 ! 54 MT
mov.l r1, @-r0 ! 30 LS
bf/s 3b ! 109 BR
mov.l r7, @-r0 ! 30 LS
! Copy the cache line aligned blocks
!
! In use: r0, r2, r4, r5
! Scratch: r1, r3, r6, r7
!
! We could do this with the four scratch registers, but if src
! and dest hit the same cache line, this will thrash, so make
! use of additional registers.
!
! We also need r0 as a temporary (for movca), so 'undo' the invariant:
! r5: src (was r0+r5)
! r1: dest (was r0)
! this can be reversed at the end, so we don't need to save any extra
! state.
!
1: mov.l r8, @-r15 ! 30 LS
add r0, r5 ! 49 EX
mov.l r9, @-r15 ! 30 LS
mov r0, r1 ! 5 MT (latency=0)
mov.l r10, @-r15 ! 30 LS
add #-0x1c, r5 ! 50 EX
mov.l r11, @-r15 ! 30 LS
! 16 cycles, 32 bytes per iteration
2: mov.l @(0x00,r5),r0 ! 18 LS (latency=2)
add #-0x20, r1 ! 50 EX
mov.l @(0x04,r5),r3 ! 18 LS (latency=2)
mov.l @(0x08,r5),r6 ! 18 LS (latency=2)
mov.l @(0x0c,r5),r7 ! 18 LS (latency=2)
mov.l @(0x10,r5),r8 ! 18 LS (latency=2)
mov.l @(0x14,r5),r9 ! 18 LS (latency=2)
mov.l @(0x18,r5),r10 ! 18 LS (latency=2)
mov.l @(0x1c,r5),r11 ! 18 LS (latency=2)
movca.l r0,@r1 ! 40 LS (latency=3-7)
mov.l r3,@(0x04,r1) ! 33 LS
mov.l r6,@(0x08,r1) ! 33 LS
mov.l r7,@(0x0c,r1) ! 33 LS
mov.l r8,@(0x10,r1) ! 33 LS
add #-0x20, r5 ! 50 EX
mov.l r9,@(0x14,r1) ! 33 LS
cmp/eq r2,r1 ! 54 MT
mov.l r10,@(0x18,r1) ! 33 LS
bf/s 2b ! 109 BR
mov.l r11,@(0x1c,r1) ! 33 LS
mov r1, r0 ! 5 MT (latency=0)
mov.l @r15+, r11 ! 15 LS
sub r1, r5 ! 75 EX
mov.l @r15+, r10 ! 15 LS
cmp/eq r4, r0 ! 54 MT
bf/s 1f ! 109 BR
mov.l @r15+, r9 ! 15 LS
rts
1: mov.l @r15+, r8 ! 15 LS
sub r4, r1 ! 75 EX (len remaining)
! number of trailing bytes is non-zero
!
! invariants restored (r5 already decremented by 4)
! also r1=num bytes remaining
mov #4, r2 ! 6 EX
mov r4, r7 ! 5 MT (latency=0)
add #0x1c, r5 ! 50 EX (back to -4)
cmp/hs r2, r1 ! 58 MT
bf/s 5f ! 108 BR
add #11, r7 ! 50 EX
mov.l @(r0, r5), r6 ! 21 LS (latency=2)
tst r2, r1 ! 86 MT
mov r5, r3 ! 5 MT (latency=0)
bt/s 4f ! 111 BR
add #-4, r3 ! 50 EX
cmp/hs r2, r1 ! 58 MT
bt/s 5f ! 111 BR
mov.l r6,@-r0 ! 30 LS
! 4 cycles, 2 long words per iteration
3: mov.l @(r0, r5), r6 ! 21 LS (latency=2)
4: mov.l @(r0, r3), r2 ! 21 LS (latency=2)
cmp/hi r7, r0
mov.l r6, @-r0 ! 30 LS
bt/s 3b ! 109 BR
mov.l r2, @-r0 ! 30 LS
! Copy the final 0-3 bytes
5: cmp/eq r0, r4 ! 54 MT
add #-10, r7 ! 50 EX
bt 9f ! 110 BR
add #3,r5 ! 50 EX
! 3 cycles, 1 byte per iteration
1: mov.b @(r0,r5),r1 ! 19 LS
cmp/hi r7,r0 ! 57 MT
bt/s 1b ! 111 BR
mov.b r1,@-r0 ! 28 LS
9: rts
nop
!
! GHIJ KLMN OPQR --> ..GH IJKL MNOP QR..
!
.balign 32
.Lcase2:
! Size is 16 or greater and less then 64, but may have trailing bytes
2: mov r5, r6 ! 5 MT (latency=0)
add #-2,r5 ! 50 EX
mov r4,r2 ! 5 MT (latency=0)
add #-4,r6 ! 50 EX
add #7,r2 ! 50 EX
3: mov.w @(r0,r5),r1 ! 20 LS (latency=2)
mov.w @(r0,r6),r3 ! 20 LS (latency=2)
cmp/hi r2,r0 ! 57 MT
mov.w r1,@-r0 ! 29 LS
bt/s 3b ! 111 BR
mov.w r3,@-r0 ! 29 LS
bra 10f
nop
.balign 32
.Lcase2b:
! Size is at least 64 bytes, so will be going round the big loop at least once.
!
! r2 = rounded up r4
! r3 = rounded down r0
mov r0, r3 ! 5 MT (latency=0)
mov #(~0x1f), r1 ! 6 EX
and r1, r3 ! 78 EX
mov r4, r2 ! 5 MT (latency=0)
cmp/eq r3, r0 ! 54 MT
add #0x1f, r2 ! 50 EX
add #-2, r5 ! 50 EX
bt/s 1f ! 110 BR
and r1, r2 ! 78 EX
! Copy a short word one at a time until we are cache line aligned
! Normal values: r0, r2, r3, r4
! Unused: r1, r6, r7
! Mod: r5 (=r5-2)
!
add #2, r3 ! 50 EX
2: mov.w @(r0,r5),r1 ! 20 LS (latency=2)
cmp/eq r3,r0 ! 54 MT
bf/s 2b ! 111 BR
mov.w r1,@-r0 ! 29 LS
! Copy the cache line aligned blocks
!
! In use: r0, r2, r4, r5 (=r5-2)
! Scratch: r1, r3, r6, r7
!
! We could do this with the four scratch registers, but if src
! and dest hit the same cache line, this will thrash, so make
! use of additional registers.
!
! We also need r0 as a temporary (for movca), so 'undo' the invariant:
! r5: src (was r0+r5)
! r1: dest (was r0)
! this can be reversed at the end, so we don't need to save any extra
! state.
!
1: mov.l r8, @-r15 ! 30 LS
add r0, r5 ! 49 EX
mov.l r9, @-r15 ! 30 LS
mov r0, r1 ! 5 MT (latency=0)
mov.l r10, @-r15 ! 30 LS
add #-0x1e, r5 ! 50 EX
mov.l r11, @-r15 ! 30 LS
mov.l r12, @-r15 ! 30 LS
! 17 cycles, 32 bytes per iteration
#ifdef CONFIG_CPU_LITTLE_ENDIAN
2: mov.w @r5+, r0 ! 14 LS (latency=2) ..JI
add #-0x20, r1 ! 50 EX
mov.l @r5+, r3 ! 15 LS (latency=2) NMLK
mov.l @r5+, r6 ! 15 LS (latency=2) RQPO
shll16 r0 ! 103 EX JI..
mov.l @r5+, r7 ! 15 LS (latency=2)
xtrct r3, r0 ! 48 EX LKJI
mov.l @r5+, r8 ! 15 LS (latency=2)
xtrct r6, r3 ! 48 EX PONM
mov.l @r5+, r9 ! 15 LS (latency=2)
xtrct r7, r6 ! 48 EX
mov.l @r5+, r10 ! 15 LS (latency=2)
xtrct r8, r7 ! 48 EX
mov.l @r5+, r11 ! 15 LS (latency=2)
xtrct r9, r8 ! 48 EX
mov.w @r5+, r12 ! 15 LS (latency=2)
xtrct r10, r9 ! 48 EX
movca.l r0,@r1 ! 40 LS (latency=3-7)
xtrct r11, r10 ! 48 EX
mov.l r3, @(0x04,r1) ! 33 LS
xtrct r12, r11 ! 48 EX
mov.l r6, @(0x08,r1) ! 33 LS
mov.l r7, @(0x0c,r1) ! 33 LS
mov.l r8, @(0x10,r1) ! 33 LS
add #-0x40, r5 ! 50 EX
mov.l r9, @(0x14,r1) ! 33 LS
cmp/eq r2,r1 ! 54 MT
mov.l r10, @(0x18,r1) ! 33 LS
bf/s 2b ! 109 BR
mov.l r11, @(0x1c,r1) ! 33 LS
#else
2: mov.w @(0x1e,r5), r0 ! 17 LS (latency=2)
add #-2, r5 ! 50 EX
mov.l @(0x1c,r5), r3 ! 18 LS (latency=2)
add #-4, r1 ! 50 EX
mov.l @(0x18,r5), r6 ! 18 LS (latency=2)
shll16 r0 ! 103 EX
mov.l @(0x14,r5), r7 ! 18 LS (latency=2)
xtrct r3, r0 ! 48 EX
mov.l @(0x10,r5), r8 ! 18 LS (latency=2)
xtrct r6, r3 ! 48 EX
mov.l @(0x0c,r5), r9 ! 18 LS (latency=2)
xtrct r7, r6 ! 48 EX
mov.l @(0x08,r5), r10 ! 18 LS (latency=2)
xtrct r8, r7 ! 48 EX
mov.l @(0x04,r5), r11 ! 18 LS (latency=2)
xtrct r9, r8 ! 48 EX
mov.l @(0x00,r5), r12 ! 18 LS (latency=2)
xtrct r10, r9 ! 48 EX
movca.l r0,@r1 ! 40 LS (latency=3-7)
add #-0x1c, r1 ! 50 EX
mov.l r3, @(0x18,r1) ! 33 LS
xtrct r11, r10 ! 48 EX
mov.l r6, @(0x14,r1) ! 33 LS
xtrct r12, r11 ! 48 EX
mov.l r7, @(0x10,r1) ! 33 LS
mov.l r8, @(0x0c,r1) ! 33 LS
add #-0x1e, r5 ! 50 EX
mov.l r9, @(0x08,r1) ! 33 LS
cmp/eq r2,r1 ! 54 MT
mov.l r10, @(0x04,r1) ! 33 LS
bf/s 2b ! 109 BR
mov.l r11, @(0x00,r1) ! 33 LS
#endif
mov.l @r15+, r12
mov r1, r0 ! 5 MT (latency=0)
mov.l @r15+, r11 ! 15 LS
sub r1, r5 ! 75 EX
mov.l @r15+, r10 ! 15 LS
cmp/eq r4, r0 ! 54 MT
bf/s 1f ! 109 BR
mov.l @r15+, r9 ! 15 LS
rts
1: mov.l @r15+, r8 ! 15 LS
add #0x1e, r5 ! 50 EX
! Finish off a short word at a time
! r5 must be invariant - 2
10: mov r4,r2 ! 5 MT (latency=0)
add #1,r2 ! 50 EX
cmp/hi r2, r0 ! 57 MT
bf/s 1f ! 109 BR
add #2, r2 ! 50 EX
3: mov.w @(r0,r5),r1 ! 20 LS
cmp/hi r2,r0 ! 57 MT
bt/s 3b ! 109 BR
mov.w r1,@-r0 ! 29 LS
1:
!
! Finally, copy the last byte if necessary
cmp/eq r4,r0 ! 54 MT
bt/s 9b
add #1,r5
mov.b @(r0,r5),r1
rts
mov.b r1,@-r0
Reference in New Issue View Git Blame Copy Permalink