blob: 7d8504d9389c78769b26d7eb3f9426b559a10988 [file] [log] [blame]
Patrick Williams975a06f2022-10-21 14:42:47 -05001From 03d97c104f2d68cffd1bfc48cd62727e13a64712 Mon Sep 17 00:00:00 2001
2From: Rui Miguel Silva <rui.silva@linaro.org>
3Date: Fri, 14 Oct 2022 17:42:52 +0100
4Subject: [PATCH] newlib: memcpy: remove optimized version
5
6When creating messages packed to send over openamp we may need
7to do some copy in unaligned address, because of that we may
8not always use the assembler optimized version, which will
9trough a data-abort on aligned address exception.
10
11So, we may just use the version in string.h (the same used in
12optee-os) that will take care to check and use different
13optimization based on given source or destination address's.
14
15Upstream-Status: Pending
16Signed-off-by: Rui Miguel Silva <rui.silva@linaro.org>
17---
18 newlib/libc/machine/aarch64/memcpy-stub.c | 2 +-
19 newlib/libc/machine/aarch64/memcpy.S | 166 ----------------------
20 2 files changed, 1 insertion(+), 167 deletions(-)
21
22diff --git a/newlib/libc/machine/aarch64/memcpy-stub.c b/newlib/libc/machine/aarch64/memcpy-stub.c
23index cd6d72a8b8af..5f2b7968c7fc 100644
24--- a/newlib/libc/machine/aarch64/memcpy-stub.c
25+++ b/newlib/libc/machine/aarch64/memcpy-stub.c
26@@ -27,5 +27,5 @@
27 #if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
28 # include "../../string/memcpy.c"
29 #else
30-/* See memcpy.S */
31+# include "../../string/memcpy.c"
32 #endif
33diff --git a/newlib/libc/machine/aarch64/memcpy.S b/newlib/libc/machine/aarch64/memcpy.S
34index 463bad0a1816..2a1460546374 100644
35--- a/newlib/libc/machine/aarch64/memcpy.S
36+++ b/newlib/libc/machine/aarch64/memcpy.S
37@@ -61,170 +61,4 @@
38 #if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED))
39 /* See memcpy-stub.c */
40 #else
41-
42-#define dstin x0
43-#define src x1
44-#define count x2
45-#define dst x3
46-#define srcend x4
47-#define dstend x5
48-#define A_l x6
49-#define A_lw w6
50-#define A_h x7
51-#define A_hw w7
52-#define B_l x8
53-#define B_lw w8
54-#define B_h x9
55-#define C_l x10
56-#define C_h x11
57-#define D_l x12
58-#define D_h x13
59-#define E_l src
60-#define E_h count
61-#define F_l srcend
62-#define F_h dst
63-#define tmp1 x9
64-
65-#define L(l) .L ## l
66-
67- .macro def_fn f p2align=0
68- .text
69- .p2align \p2align
70- .global \f
71- .type \f, %function
72-\f:
73- .endm
74-
75-/* Copies are split into 3 main cases: small copies of up to 16 bytes,
76- medium copies of 17..96 bytes which are fully unrolled. Large copies
77- of more than 96 bytes align the destination and use an unrolled loop
78- processing 64 bytes per iteration.
79- Small and medium copies read all data before writing, allowing any
80- kind of overlap, and memmove tailcalls memcpy for these cases as
81- well as non-overlapping copies.
82-*/
83-
84-def_fn memcpy p2align=6
85- prfm PLDL1KEEP, [src]
86- add srcend, src, count
87- add dstend, dstin, count
88- cmp count, 16
89- b.ls L(copy16)
90- cmp count, 96
91- b.hi L(copy_long)
92-
93- /* Medium copies: 17..96 bytes. */
94- sub tmp1, count, 1
95- ldp A_l, A_h, [src]
96- tbnz tmp1, 6, L(copy96)
97- ldp D_l, D_h, [srcend, -16]
98- tbz tmp1, 5, 1f
99- ldp B_l, B_h, [src, 16]
100- ldp C_l, C_h, [srcend, -32]
101- stp B_l, B_h, [dstin, 16]
102- stp C_l, C_h, [dstend, -32]
103-1:
104- stp A_l, A_h, [dstin]
105- stp D_l, D_h, [dstend, -16]
106- ret
107-
108- .p2align 4
109- /* Small copies: 0..16 bytes. */
110-L(copy16):
111- cmp count, 8
112- b.lo 1f
113- ldr A_l, [src]
114- ldr A_h, [srcend, -8]
115- str A_l, [dstin]
116- str A_h, [dstend, -8]
117- ret
118- .p2align 4
119-1:
120- tbz count, 2, 1f
121- ldr A_lw, [src]
122- ldr A_hw, [srcend, -4]
123- str A_lw, [dstin]
124- str A_hw, [dstend, -4]
125- ret
126-
127- /* Copy 0..3 bytes. Use a branchless sequence that copies the same
128- byte 3 times if count==1, or the 2nd byte twice if count==2. */
129-1:
130- cbz count, 2f
131- lsr tmp1, count, 1
132- ldrb A_lw, [src]
133- ldrb A_hw, [srcend, -1]
134- ldrb B_lw, [src, tmp1]
135- strb A_lw, [dstin]
136- strb B_lw, [dstin, tmp1]
137- strb A_hw, [dstend, -1]
138-2: ret
139-
140- .p2align 4
141- /* Copy 64..96 bytes. Copy 64 bytes from the start and
142- 32 bytes from the end. */
143-L(copy96):
144- ldp B_l, B_h, [src, 16]
145- ldp C_l, C_h, [src, 32]
146- ldp D_l, D_h, [src, 48]
147- ldp E_l, E_h, [srcend, -32]
148- ldp F_l, F_h, [srcend, -16]
149- stp A_l, A_h, [dstin]
150- stp B_l, B_h, [dstin, 16]
151- stp C_l, C_h, [dstin, 32]
152- stp D_l, D_h, [dstin, 48]
153- stp E_l, E_h, [dstend, -32]
154- stp F_l, F_h, [dstend, -16]
155- ret
156-
157- /* Align DST to 16 byte alignment so that we don't cross cache line
158- boundaries on both loads and stores. There are at least 96 bytes
159- to copy, so copy 16 bytes unaligned and then align. The loop
160- copies 64 bytes per iteration and prefetches one iteration ahead. */
161-
162- .p2align 4
163-L(copy_long):
164- and tmp1, dstin, 15
165- bic dst, dstin, 15
166- ldp D_l, D_h, [src]
167- sub src, src, tmp1
168- add count, count, tmp1 /* Count is now 16 too large. */
169- ldp A_l, A_h, [src, 16]
170- stp D_l, D_h, [dstin]
171- ldp B_l, B_h, [src, 32]
172- ldp C_l, C_h, [src, 48]
173- ldp D_l, D_h, [src, 64]!
174- subs count, count, 128 + 16 /* Test and readjust count. */
175- b.ls 2f
176-1:
177- stp A_l, A_h, [dst, 16]
178- ldp A_l, A_h, [src, 16]
179- stp B_l, B_h, [dst, 32]
180- ldp B_l, B_h, [src, 32]
181- stp C_l, C_h, [dst, 48]
182- ldp C_l, C_h, [src, 48]
183- stp D_l, D_h, [dst, 64]!
184- ldp D_l, D_h, [src, 64]!
185- subs count, count, 64
186- b.hi 1b
187-
188- /* Write the last full set of 64 bytes. The remainder is at most 64
189- bytes, so it is safe to always copy 64 bytes from the end even if
190- there is just 1 byte left. */
191-2:
192- ldp E_l, E_h, [srcend, -64]
193- stp A_l, A_h, [dst, 16]
194- ldp A_l, A_h, [srcend, -48]
195- stp B_l, B_h, [dst, 32]
196- ldp B_l, B_h, [srcend, -32]
197- stp C_l, C_h, [dst, 48]
198- ldp C_l, C_h, [srcend, -16]
199- stp D_l, D_h, [dst, 64]
200- stp E_l, E_h, [dstend, -64]
201- stp A_l, A_h, [dstend, -48]
202- stp B_l, B_h, [dstend, -32]
203- stp C_l, C_h, [dstend, -16]
204- ret
205-
206- .size memcpy, . - memcpy
207 #endif
208--
2092.38.0
210