aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--sysdeps/powerpc/powerpc64/le/power10/strlen.S221
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/Makefile3
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c2
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strlen-power10.S2
-rw-r--r--sysdeps/powerpc/powerpc64/multiarch/strlen.c3
5 files changed, 230 insertions, 1 deletions
diff --git a/sysdeps/powerpc/powerpc64/le/power10/strlen.S b/sysdeps/powerpc/powerpc64/le/power10/strlen.S
new file mode 100644
index 0000000..ca7e9eb
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/le/power10/strlen.S
@@ -0,0 +1,221 @@
+/* Optimized strlen implementation for POWER10 LE.
+ Copyright (C) 2021 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <sysdep.h>
+
+#ifndef STRLEN
+# define STRLEN __strlen
+# define DEFINE_STRLEN_HIDDEN_DEF 1
+#endif
+
+/* TODO: Replace macros by the actual instructions when minimum binutils becomes
+ >= 2.35. This is used to keep compatibility with older versions. */
+#define VEXTRACTBM(rt,vrb) \
+ .long(((4)<<(32-6)) \
+ | ((rt)<<(32-11)) \
+ | ((8)<<(32-16)) \
+ | ((vrb)<<(32-21)) \
+ | 1602)
+
+#define LXVP(xtp,dq,ra) \
+ .long(((6)<<(32-6)) \
+ | ((((xtp)-32)>>1)<<(32-10)) \
+ | ((1)<<(32-11)) \
+ | ((ra)<<(32-16)) \
+ | dq)
+
+#define CHECK16(vreg,offset,addr,label) \
+ lxv vreg+32,offset(addr); \
+ vcmpequb. vreg,vreg,v18; \
+ bne cr6,L(label);
+
+/* Load 4 quadwords, merge into one VR for speed and check for NULLs. r6 has #
+ of bytes already checked. */
+#define CHECK64(offset,addr,label) \
+ li r6,offset; \
+ LXVP(v4+32,offset,addr); \
+ LXVP(v6+32,offset+32,addr); \
+ vminub v14,v4,v5; \
+ vminub v15,v6,v7; \
+ vminub v16,v14,v15; \
+ vcmpequb. v0,v16,v18; \
+ bne cr6,L(label)
+
+#define TAIL(vreg,increment) \
+ vctzlsbb r4,vreg; \
+ subf r3,r3,r5; \
+ addi r4,r4,increment; \
+ add r3,r3,r4; \
+ blr
+
+/* Implements the function
+
+ int [r3] strlen (const void *s [r3])
+
+ The implementation can load bytes past a matching byte, but only
+ up to the next 64B boundary, so it never crosses a page. */
+
+.machine power9
+
+ENTRY_TOCLESS (STRLEN, 4)
+ CALL_MCOUNT 1
+
+ vspltisb v18,0
+ vspltisb v19,-1
+
+ /* Next 16B-aligned address. Prepare address for L(aligned). */
+ addi r5,r3,16
+ clrrdi r5,r5,4
+
+ /* Align data and fill bytes not loaded with non matching char. */
+ lvx v0,0,r3
+ lvsr v1,0,r3
+ vperm v0,v19,v0,v1
+
+ vcmpequb. v6,v0,v18
+ beq cr6,L(aligned)
+
+ vctzlsbb r3,v6
+ blr
+
+ /* Test next 176B, 16B at a time. The main loop is optimized for longer
+ strings, so checking the first bytes in 16B chunks benefits a lot
+ small strings. */
+ .p2align 5
+L(aligned):
+ /* Prepare address for the loop. */
+ addi r4,r3,192
+ clrrdi r4,r4,6
+
+ CHECK16(v0,0,r5,tail1)
+ CHECK16(v1,16,r5,tail2)
+ CHECK16(v2,32,r5,tail3)
+ CHECK16(v3,48,r5,tail4)
+ CHECK16(v4,64,r5,tail5)
+ CHECK16(v5,80,r5,tail6)
+ CHECK16(v6,96,r5,tail7)
+ CHECK16(v7,112,r5,tail8)
+ CHECK16(v8,128,r5,tail9)
+ CHECK16(v9,144,r5,tail10)
+ CHECK16(v10,160,r5,tail11)
+
+ addi r5,r4,128
+
+ /* Switch to a more aggressive approach checking 64B each time. Use 2
+ pointers 128B apart and unroll the loop once to make the pointer
+ updates and usages separated enough to avoid stalls waiting for
+ address calculation. */
+ .p2align 5
+L(loop):
+ CHECK64(0,r4,pre_tail_64b)
+ CHECK64(64,r4,pre_tail_64b)
+ addi r4,r4,256
+
+ CHECK64(0,r5,tail_64b)
+ CHECK64(64,r5,tail_64b)
+ addi r5,r5,256
+
+ b L(loop)
+
+ .p2align 5
+L(pre_tail_64b):
+ mr r5,r4
+L(tail_64b):
+ /* OK, we found a null byte. Let's look for it in the current 64-byte
+ block and mark it in its corresponding VR. lxvp vx,0(ry) puts the
+ low 16B bytes into vx+1, and the high into vx, so the order here is
+ v5, v4, v7, v6. */
+ vcmpequb v1,v5,v18
+ vcmpequb v2,v4,v18
+ vcmpequb v3,v7,v18
+ vcmpequb v4,v6,v18
+
+ /* Take into account the other 64B blocks we had already checked. */
+ add r5,r5,r6
+
+ /* Extract first bit of each byte. */
+ VEXTRACTBM(r7,v1)
+ VEXTRACTBM(r8,v2)
+ VEXTRACTBM(r9,v3)
+ VEXTRACTBM(r10,v4)
+
+ /* Shift each value into their corresponding position. */
+ sldi r8,r8,16
+ sldi r9,r9,32
+ sldi r10,r10,48
+
+ /* Merge the results. */
+ or r7,r7,r8
+ or r8,r9,r10
+ or r10,r8,r7
+
+ cnttzd r0,r10 /* Count trailing zeros before the match. */
+ subf r5,r3,r5
+ add r3,r5,r0 /* Compute final length. */
+ blr
+
+ .p2align 5
+L(tail1):
+ TAIL(v0,0)
+
+ .p2align 5
+L(tail2):
+ TAIL(v1,16)
+
+ .p2align 5
+L(tail3):
+ TAIL(v2,32)
+
+ .p2align 5
+L(tail4):
+ TAIL(v3,48)
+
+ .p2align 5
+L(tail5):
+ TAIL(v4,64)
+
+ .p2align 5
+L(tail6):
+ TAIL(v5,80)
+
+ .p2align 5
+L(tail7):
+ TAIL(v6,96)
+
+ .p2align 5
+L(tail8):
+ TAIL(v7,112)
+
+ .p2align 5
+L(tail9):
+ TAIL(v8,128)
+
+ .p2align 5
+L(tail10):
+ TAIL(v9,144)
+
+ .p2align 5
+L(tail11):
+ TAIL(v10,160)
+
+END (STRLEN)
+
+#ifdef DEFINE_STRLEN_HIDDEN_DEF
+weak_alias (__strlen, strlen)
+libc_hidden_builtin_def (strlen)
+#endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/Makefile b/sysdeps/powerpc/powerpc64/multiarch/Makefile
index f46bf50..8aa46a3 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/Makefile
+++ b/sysdeps/powerpc/powerpc64/multiarch/Makefile
@@ -33,7 +33,8 @@ sysdep_routines += memcpy-power8-cached memcpy-power7 memcpy-a2 memcpy-power6 \
ifneq (,$(filter %le,$(config-machine)))
sysdep_routines += strcmp-power9 strncmp-power9 strcpy-power9 stpcpy-power9 \
- rawmemchr-power9 strlen-power9 strncpy-power9 stpncpy-power9
+ rawmemchr-power9 strlen-power9 strncpy-power9 stpncpy-power9 \
+ strlen-power10
endif
CFLAGS-strncase-power7.c += -mcpu=power7 -funroll-loops
CFLAGS-strncase_l-power7.c += -mcpu=power7 -funroll-loops
diff --git a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
index 72f7f83..1a69936 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/ifunc-impl-list.c
@@ -112,6 +112,8 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
/* Support sysdeps/powerpc/powerpc64/multiarch/strlen.c. */
IFUNC_IMPL (i, name, strlen,
#ifdef __LITTLE_ENDIAN__
+ IFUNC_IMPL_ADD (array, i, strlen, hwcap2 & PPC_FEATURE2_ARCH_3_1,
+ __strlen_power10)
IFUNC_IMPL_ADD (array, i, strlen, hwcap2 & PPC_FEATURE2_ARCH_3_00,
__strlen_power9)
#endif
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strlen-power10.S b/sysdeps/powerpc/powerpc64/multiarch/strlen-power10.S
new file mode 100644
index 0000000..6a774fa
--- /dev/null
+++ b/sysdeps/powerpc/powerpc64/multiarch/strlen-power10.S
@@ -0,0 +1,2 @@
+#define STRLEN __strlen_power10
+#include <sysdeps/powerpc/powerpc64/le/power10/strlen.S>
diff --git a/sysdeps/powerpc/powerpc64/multiarch/strlen.c b/sysdeps/powerpc/powerpc64/multiarch/strlen.c
index c3bbc78..109c8a9 100644
--- a/sysdeps/powerpc/powerpc64/multiarch/strlen.c
+++ b/sysdeps/powerpc/powerpc64/multiarch/strlen.c
@@ -31,9 +31,12 @@ extern __typeof (__redirect_strlen) __strlen_ppc attribute_hidden;
extern __typeof (__redirect_strlen) __strlen_power7 attribute_hidden;
extern __typeof (__redirect_strlen) __strlen_power8 attribute_hidden;
extern __typeof (__redirect_strlen) __strlen_power9 attribute_hidden;
+extern __typeof (__redirect_strlen) __strlen_power10 attribute_hidden;
libc_ifunc (__libc_strlen,
# ifdef __LITTLE_ENDIAN__
+ (hwcap2 & PPC_FEATURE2_ARCH_3_1)
+ ? __strlen_power10 :
(hwcap2 & PPC_FEATURE2_ARCH_3_00)
? __strlen_power9 :
# endif