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-rw-r--r--sysdeps/aarch64/multiarch/Makefile3
-rw-r--r--sysdeps/aarch64/multiarch/ifunc-impl-list.c1
-rw-r--r--sysdeps/aarch64/multiarch/memset.c5
-rw-r--r--sysdeps/aarch64/multiarch/memset_base64.S178
-rw-r--r--sysdeps/aarch64/multiarch/memset_emag.S32
5 files changed, 217 insertions, 2 deletions
diff --git a/sysdeps/aarch64/multiarch/Makefile b/sysdeps/aarch64/multiarch/Makefile
index b1a5f59fcd..3c6c879997 100644
--- a/sysdeps/aarch64/multiarch/Makefile
+++ b/sysdeps/aarch64/multiarch/Makefile
@@ -1,5 +1,6 @@
ifeq ($(subdir),string)
sysdep_routines += memcpy_generic memcpy_thunderx memcpy_thunderx2 \
- memcpy_falkor memmove_falkor memset_generic memset_falkor \
+ memcpy_falkor memmove_falkor \
+ memset_generic memset_falkor memset_emag \
strlen_generic strlen_asimd
endif
diff --git a/sysdeps/aarch64/multiarch/ifunc-impl-list.c b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
index a00c329bca..d1f7df61d7 100644
--- a/sysdeps/aarch64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/aarch64/multiarch/ifunc-impl-list.c
@@ -51,6 +51,7 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Enable this on non-falkor processors too so that other cores
can do a comparative analysis with __memset_generic. */
IFUNC_IMPL_ADD (array, i, memset, (zva_size == 64), __memset_falkor)
+ IFUNC_IMPL_ADD (array, i, memset, (zva_size == 64), __memset_emag)
IFUNC_IMPL_ADD (array, i, memset, 1, __memset_generic))
IFUNC_IMPL (i, name, strlen,
diff --git a/sysdeps/aarch64/multiarch/memset.c b/sysdeps/aarch64/multiarch/memset.c
index 6ba8630a18..481758702f 100644
--- a/sysdeps/aarch64/multiarch/memset.c
+++ b/sysdeps/aarch64/multiarch/memset.c
@@ -29,12 +29,15 @@
extern __typeof (__redirect_memset) __libc_memset;
extern __typeof (__redirect_memset) __memset_falkor attribute_hidden;
+extern __typeof (__redirect_memset) __memset_emag attribute_hidden;
extern __typeof (__redirect_memset) __memset_generic attribute_hidden;
libc_ifunc (__libc_memset,
((IS_FALKOR (midr) || IS_PHECDA (midr)) && zva_size == 64
? __memset_falkor
- : __memset_generic));
+ : (IS_EMAG (midr) && zva_size == 64
+ ? __memset_emag
+ : __memset_generic)));
# undef memset
strong_alias (__libc_memset, memset);
diff --git a/sysdeps/aarch64/multiarch/memset_base64.S b/sysdeps/aarch64/multiarch/memset_base64.S
new file mode 100644
index 0000000000..9a623259b9
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memset_base64.S
@@ -0,0 +1,178 @@
+/* Copyright (C) 2018 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/>. */
+
+#include <sysdep.h>
+#include "memset-reg.h"
+
+#ifndef MEMSET
+# define MEMSET __memset_base64
+#endif
+
+#ifndef DC_ZVA_THRESHOLD
+# define DC_ZVA_THRESHOLD 512
+#endif
+
+/* Assumptions:
+ *
+ * ARMv8-a, AArch64, unaligned accesses
+ *
+ */
+
+ENTRY_ALIGN (MEMSET, 6)
+
+ DELOUSE (0)
+ DELOUSE (2)
+
+ bfi valw, valw, 8, 8
+ bfi valw, valw, 16, 16
+ bfi val, val, 32, 32
+
+ add dstend, dstin, count
+
+ cmp count, 96
+ b.hi L(set_long)
+ cmp count, 16
+ b.hs L(set_medium)
+
+ /* Set 0..15 bytes. */
+ tbz count, 3, 1f
+ str val, [dstin]
+ str val, [dstend, -8]
+ ret
+
+ .p2align 3
+1: tbz count, 2, 2f
+ str valw, [dstin]
+ str valw, [dstend, -4]
+ ret
+2: cbz count, 3f
+ strb valw, [dstin]
+ tbz count, 1, 3f
+ strh valw, [dstend, -2]
+3: ret
+
+ .p2align 3
+ /* Set 16..96 bytes. */
+L(set_medium):
+ stp val, val, [dstin]
+ tbnz count, 6, L(set96)
+ stp val, val, [dstend, -16]
+ tbz count, 5, 1f
+ stp val, val, [dstin, 16]
+ stp val, val, [dstend, -32]
+1: ret
+
+ .p2align 4
+ /* Set 64..96 bytes. Write 64 bytes from the start and
+ 32 bytes from the end. */
+L(set96):
+ stp val, val, [dstin, 16]
+ stp val, val, [dstin, 32]
+ stp val, val, [dstin, 48]
+ stp val, val, [dstend, -32]
+ stp val, val, [dstend, -16]
+ ret
+
+ .p2align 4
+L(set_long):
+ stp val, val, [dstin]
+ cmp count, DC_ZVA_THRESHOLD
+ ccmp val, 0, 0, cs
+ bic dst, dstin, 15
+ b.eq L(zva_64)
+
+ /* Small-size or non-zero memset does not use DC ZVA. */
+ sub count, dstend, dst
+
+ /*
+ * Adjust count and bias for loop. By substracting extra 1 from count,
+ * it is easy to use tbz instruction to check whether loop tailing
+ * count is less than 33 bytes, so as to bypass 2 unneccesary stps.
+ */
+ sub count, count, 64+16+1
+ nop
+
+1: stp val, val, [dst, 16]
+ stp val, val, [dst, 32]
+ stp val, val, [dst, 48]
+ stp val, val, [dst, 64]!
+ subs count, count, 64
+ b.hs 1b
+
+ tbz count, 5, 1f /* Remaining count is less than 33 bytes? */
+ stp val, val, [dst, 16]
+ stp val, val, [dst, 32]
+1: stp val, val, [dstend, -32]
+ stp val, val, [dstend, -16]
+ ret
+
+ .p2align 3
+L(zva_64):
+ stp val, val, [dst, 16]
+ stp val, val, [dst, 32]
+ stp val, val, [dst, 48]
+ bic dst, dst, 63
+
+ /*
+ * Previous memory writes might cross cache line boundary, and cause
+ * cache line partially dirty. Zeroing this kind of cache line using
+ * DC ZVA will incur extra cost, for it requires loading untouched
+ * part of the line from memory before zeoring.
+ *
+ * So, write the first 64 byte aligned block using stp to force
+ * fully dirty cache line.
+ */
+ stp val, val, [dst, 64]
+ stp val, val, [dst, 80]
+ stp val, val, [dst, 96]
+ stp val, val, [dst, 112]
+
+ sub count, dstend, dst
+ /*
+ * Adjust count and bias for loop. By substracting extra 1 from count,
+ * it is easy to use tbz instruction to check whether loop tailing
+ * count is less than 33 bytes, so as to bypass 2 unneccesary stps.
+ */
+ sub count, count, 128+64+64+1
+ add dst, dst, 128
+ nop
+
+ /* DC ZVA sets 64 bytes each time. */
+1: dc zva, dst
+ add dst, dst, 64
+ subs count, count, 64
+ b.hs 1b
+
+ /*
+ * Write the last 64 byte aligned block using stp to force fully
+ * dirty cache line.
+ */
+ stp val, val, [dst, 0]
+ stp val, val, [dst, 16]
+ stp val, val, [dst, 32]
+ stp val, val, [dst, 48]
+
+ tbz count, 5, 1f /* Remaining count is less than 33 bytes? */
+ stp val, val, [dst, 64]
+ stp val, val, [dst, 80]
+1: stp val, val, [dstend, -32]
+ stp val, val, [dstend, -16]
+ ret
+
+END (MEMSET)
+libc_hidden_builtin_def (MEMSET)
diff --git a/sysdeps/aarch64/multiarch/memset_emag.S b/sysdeps/aarch64/multiarch/memset_emag.S
new file mode 100644
index 0000000000..1c1fabc624
--- /dev/null
+++ b/sysdeps/aarch64/multiarch/memset_emag.S
@@ -0,0 +1,32 @@
+/* Optimized memset for AmpereComputing emag processor.
+ Copyright (C) 2018 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/>. */
+
+#if IS_IN (libc)
+# define MEMSET __memset_emag
+
+/*
+ * Using dc zva to zero memory does not produce better performance if
+ * memory size is not very large, especially when there are multiple
+ * processes/threads contending memory/cache. Here we use a somewhat
+ * large threshold to trigger usage of dc zva.
+*/
+# define DC_ZVA_THRESHOLD 1024
+
+# include "./memset_base64.S"
+#endif