From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org,
Richard Henderson <richard.henderson@linaro.org>,
Noah Goldstein <goldstein.w.n@gmail.com>
Subject: [PATCH v9 12/22] hppa: Add string-fzb.h and string-fzi.h
Date: Tue, 17 Jan 2023 17:00:04 -0300 [thread overview]
Message-ID: <20230117200014.1299923-13-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20230117200014.1299923-1-adhemerval.zanella@linaro.org>
From: Richard Henderson <richard.henderson@linaro.org>
Use UXOR,SBZ to test for a zero byte within a word. While we can
get semi-decent code out of asm-goto, we would do slightly better
with a compiler builtin.
For index_zero et al, sequential testing of bytes is less expensive than
any tricks that involve a count-leading-zeros insn that we don't have.
Checked on hppa-linux-gnu.
---
sysdeps/hppa/string-fzb.h | 70 +++++++++++++++++++++
sysdeps/hppa/string-fzc.h | 124 ++++++++++++++++++++++++++++++++++++++
sysdeps/hppa/string-fzi.h | 63 +++++++++++++++++++
3 files changed, 257 insertions(+)
create mode 100644 sysdeps/hppa/string-fzb.h
create mode 100644 sysdeps/hppa/string-fzc.h
create mode 100644 sysdeps/hppa/string-fzi.h
diff --git a/sysdeps/hppa/string-fzb.h b/sysdeps/hppa/string-fzb.h
new file mode 100644
index 0000000000..865e548492
--- /dev/null
+++ b/sysdeps/hppa/string-fzb.h
@@ -0,0 +1,70 @@
+/* Zero byte detection, boolean. HPPA version.
+ Copyright (C) 2023 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/>. */
+
+#ifndef _STRING_FZB_H
+#define _STRING_FZB_H 1
+
+#include <sys/cdefs.h>
+#include <string-optype.h>
+
+/* Determine if any byte within X is zero. This is a pure boolean test. */
+
+static __always_inline _Bool
+has_zero (op_t x)
+{
+ _Static_assert (sizeof (op_t) == 4, "64-bit not supported");
+
+ /* It's more useful to expose a control transfer to the compiler
+ than to expose a proper boolean result. */
+ asm goto ("uxor,sbz %%r0,%0,%%r0\n\t"
+ "b,n %l1" : : "r"(x) : : nbz);
+ return 1;
+ nbz:
+ return 0;
+}
+
+/* Likewise, but for byte equality between X1 and X2. */
+
+static __always_inline _Bool
+has_eq (op_t x1, op_t x2)
+{
+ _Static_assert (sizeof (op_t) == 4, "64-bit not supported");
+
+ asm goto ("uxor,sbz %0,%1,%%r0\n\t"
+ "b,n %l2" : : "r"(x1), "r"(x2) : : nbz);
+ return 1;
+ nbz:
+ return 0;
+}
+
+/* Likewise, but for zeros in X1 and equal bytes between X1 and X2. */
+
+static __always_inline _Bool
+has_zero_eq (op_t x1, op_t x2)
+{
+ _Static_assert (sizeof (op_t) == 4, "64-bit not supported");
+
+ asm goto ("uxor,sbz %%r0,%0,%%r0\n\t"
+ "uxor,nbz %0,%1,%%r0\n\t"
+ "b,n %l2" : : "r"(x1), "r"(x2) : : sbz);
+ return 0;
+ sbz:
+ return 1;
+}
+
+#endif /* _STRING_FZB_H */
diff --git a/sysdeps/hppa/string-fzc.h b/sysdeps/hppa/string-fzc.h
new file mode 100644
index 0000000000..8ff3416b41
--- /dev/null
+++ b/sysdeps/hppa/string-fzc.h
@@ -0,0 +1,124 @@
+/* string-fzc.h -- zero byte detection with indexes. HPPA version.
+ Copyright (C) 2022 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/>. */
+
+#ifndef _STRING_FZC_H
+#define _STRING_FZC_H 1
+
+#include <string-optype.h>
+
+_Static_assert (sizeof (op_t) == 4, "64-bit not supported");
+
+/* Given a word X that is known to contain a zero byte, return the
+ index of the first such within the long in memory order. */
+static __always_inline unsigned int
+index_first_zero (op_t x)
+{
+ unsigned int ret;
+
+ /* Since we have no clz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,<> %1,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,<> %1,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,<> %1,7,8,%%r0\n\t"
+ "ldi 0,%0"
+ : "=r"(ret) : "r"(x), "0"(3));
+
+ return ret;
+}
+
+/* Similarly, but perform the search for byte equality between X1 and X2. */
+static __always_inline unsigned int
+index_first_eq (op_t x1, op_t x2)
+{
+ return index_first_zero (x1 ^ x2);
+}
+
+/* Similarly, but perform the search for zero within X1 or
+ equality between X1 and X2. */
+static __always_inline unsigned int
+index_first_zero_eq (op_t x1, op_t x2)
+{
+ unsigned int ret;
+
+ /* Since we have no clz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,= %1,23,8,%%r0\n\t"
+ "extrw,u,<> %2,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,= %1,15,8,%%r0\n\t"
+ "extrw,u,<> %2,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,= %1,7,8,%%r0\n\t"
+ "extrw,u,<> %2,7,8,%%r0\n\t"
+ "ldi 0,%0"
+ : "=r"(ret) : "r"(x1), "r"(x1 ^ x2), "0"(3));
+
+ return ret;
+}
+
+/* Similarly, but perform the search for zero within X1 or
+ inequality between X1 and X2. */
+static __always_inline unsigned int
+index_first_zero_ne (op_t x1, op_t x2)
+{
+ unsigned int ret;
+
+ /* Since we have no clz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,<> %2,23,8,%%r0\n\t"
+ "extrw,u,<> %1,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,<> %2,15,8,%%r0\n\t"
+ "extrw,u,<> %1,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,<> %2,7,8,%%r0\n\t"
+ "extrw,u,<> %1,7,8,%%r0\n\t"
+ "ldi 0,%0"
+ : "=r"(ret) : "r"(x1), "r"(x1 ^ x2), "0"(3));
+
+ return ret;
+}
+
+/* Similarly, but search for the last zero within X. */
+static __always_inline unsigned int
+index_last_zero (op_t x)
+{
+ unsigned int ret;
+
+ /* Since we have no ctz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,<> %1,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,<> %1,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,<> %1,31,8,%%r0\n\t"
+ "ldi 3,%0"
+ : "=r"(ret) : "r"(x), "0"(0));
+
+ return ret;
+}
+
+static __always_inline unsigned int
+index_last_eq (op_t x1, op_t x2)
+{
+ return index_last_zero (x1 ^ x2);
+}
+
+#endif /* _STRING_FZC_H */
diff --git a/sysdeps/hppa/string-fzi.h b/sysdeps/hppa/string-fzi.h
new file mode 100644
index 0000000000..b560fa1a89
--- /dev/null
+++ b/sysdeps/hppa/string-fzi.h
@@ -0,0 +1,63 @@
+/* string-fzi.h -- zero byte indexes. HPPA version.
+ Copyright (C) 2022 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/>. */
+
+#ifndef _STRING_FZI_H
+#define _STRING_FZI_H 1
+
+#include <string-optype.h>
+#include <string-fza.h>
+
+_Static_assert (sizeof (op_t) == 4, "64-bit not supported");
+
+static __always_inline unsigned int
+index_first (find_t c)
+{
+ unsigned int ret;
+
+ /* Since we have no clz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,= %1,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,= %1,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,= %1,7,8,%%r0\n\t"
+ "ldi 0,%0"
+ : "=r"(ret) : "r"(c), "0"(3));
+
+ return ret;
+}
+
+static __always_inline unsigned int
+index_last (find_t c)
+{
+ unsigned int ret;
+
+ /* Since we have no ctz insn, direct tests of the bytes is faster
+ than loading up the constants to do the masking. */
+ asm ("extrw,u,= %1,15,8,%%r0\n\t"
+ "ldi 1,%0\n\t"
+ "extrw,u,= %1,23,8,%%r0\n\t"
+ "ldi 2,%0\n\t"
+ "extrw,u,= %1,31,8,%%r0\n\t"
+ "ldi 3,%0"
+ : "=r"(ret) : "r"(c), "0"(0));
+
+ return ret;
+}
+
+#endif /* _STRING_FZI_H */
--
2.34.1
next prev parent reply other threads:[~2023-01-17 20:00 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-17 19:59 [PATCH v9 00/22] Improve generic string routines Adhemerval Zanella
2023-01-17 19:59 ` [PATCH v9 01/22] Parameterize op_t from memcopy.h Adhemerval Zanella
2023-01-17 19:59 ` [PATCH v9 02/22] Parameterize OP_T_THRES " Adhemerval Zanella
2023-01-17 19:59 ` [PATCH v9 03/22] Add string vectorized find and detection functions Adhemerval Zanella
2023-01-18 1:35 ` Richard Henderson
2023-01-18 1:54 ` Richard Henderson
2023-01-18 12:42 ` Adhemerval Zanella Netto
2023-01-18 19:24 ` Richard Henderson
2023-01-18 19:38 ` Adhemerval Zanella Netto
2023-01-17 19:59 ` [PATCH v9 04/22] string: Improve generic strlen Adhemerval Zanella
2023-01-17 19:59 ` [PATCH v9 05/22] string: Improve generic strnlen Adhemerval Zanella
2023-01-17 19:59 ` [PATCH v9 06/22] string: Improve generic strchr Adhemerval Zanella
2023-01-18 1:42 ` Richard Henderson
2023-01-17 19:59 ` [PATCH v9 07/22] string: Improve generic strchrnul Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 08/22] string: Improve generic strcmp Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 09/22] string: Improve generic memchr Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 10/22] string: Improve generic memrchr Adhemerval Zanella
2023-01-18 2:10 ` Richard Henderson
2023-01-17 20:00 ` [PATCH v9 11/22] hppa: Add memcopy.h Adhemerval Zanella
2023-01-17 20:00 ` Adhemerval Zanella [this message]
2023-01-17 20:00 ` [PATCH v9 13/22] alpha: Add string-fzb.h and string-fzi.h Adhemerval Zanella
2023-01-18 1:58 ` Richard Henderson
2023-01-17 20:00 ` [PATCH v9 14/22] arm: Add string-fza.h Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 15/22] powerpc: " Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 16/22] sh: Add string-fzb.h Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 17/22] string: Hook up the default implementation on test-strlen Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 18/22] string: Hook up the default implementation on test-strnlen Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 19/22] string: Hook up the default implementation on test-strchr Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 20/22] string: Hook up the default implementation on test-strcmp Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 21/22] string: Hook up the default implementation on test-memchr Adhemerval Zanella
2023-01-17 20:00 ` [PATCH v9 22/22] string: Hook up the default implementation on test-memrchr Adhemerval Zanella
2023-01-18 18:51 ` Carlos O'Donell
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230117200014.1299923-13-adhemerval.zanella@linaro.org \
--to=adhemerval.zanella@linaro.org \
--cc=goldstein.w.n@gmail.com \
--cc=libc-alpha@sourceware.org \
--cc=richard.henderson@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).