From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org,
Richard Henderson <richard.henderson@linaro.org>,
Jeff Law <jeffreyalaw@gmail.com>, Xi Ruoyao <xry111@xry111.site>,
Noah Goldstein <goldstein.w.n@gmail.com>
Subject: [PATCH v12 17/31] alpha: Add string-fza, string-fzb.h, string-fzi.h, and string-shift.h
Date: Thu, 2 Feb 2023 15:11:35 -0300 [thread overview]
Message-ID: <20230202181149.2181553-18-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20230202181149.2181553-1-adhemerval.zanella@linaro.org>
From: Richard Henderson <richard.henderson@linaro.org>
While alpha has the more important string functions in assembly,
there are still a few for find the generic routines are used.
Use the CMPBGE insn, via the builtin, for testing of zeros. Use a
simplified expansion of __builtin_ctz when the insn isn't available.
Checked on alpha-linux-gnu.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
sysdeps/alpha/string-fza.h | 61 +++++++++++++++++++++++++++++++++++
sysdeps/alpha/string-fzb.h | 52 ++++++++++++++++++++++++++++++
sysdeps/alpha/string-fzi.h | 62 ++++++++++++++++++++++++++++++++++++
sysdeps/alpha/string-shift.h | 44 +++++++++++++++++++++++++
4 files changed, 219 insertions(+)
create mode 100644 sysdeps/alpha/string-fza.h
create mode 100644 sysdeps/alpha/string-fzb.h
create mode 100644 sysdeps/alpha/string-fzi.h
create mode 100644 sysdeps/alpha/string-shift.h
diff --git a/sysdeps/alpha/string-fza.h b/sysdeps/alpha/string-fza.h
new file mode 100644
index 0000000000..b4a7080c44
--- /dev/null
+++ b/sysdeps/alpha/string-fza.h
@@ -0,0 +1,61 @@
+/* Basic zero byte detection. Generic C 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_FZA_H
+#define _STRING_FZA_H 1
+
+#include <string-misc.h>
+#include <string-optype.h>
+
+/* The CMPBGE instruction creates a bit mask rather than a byte mask.
+ However, if we narrow find_t to either 'int' or 'uint8_t', we get
+ unnecessary truncation instructions from the 'unsigned long' type
+ returned by __builtin_alpha_cmpbge. */
+typedef op_t find_t;
+
+static __always_inline find_t
+find_zero_all (op_t x)
+{
+ return __builtin_alpha_cmpbge (0, x);
+}
+
+static __always_inline find_t
+find_eq_all (op_t x1, op_t x2)
+{
+ return find_zero_all (x1 ^ x2);
+}
+
+static __always_inline find_t
+find_zero_eq_all (op_t x1, op_t x2)
+{
+ return find_zero_all (x1) | find_zero_all (x1 ^ x2);
+}
+
+static __always_inline find_t
+find_zero_ne_all (op_t x1, op_t x2)
+{
+ return find_zero_all (x1) | (find_zero_all (x1 ^ x2) ^ 0xff);
+}
+
+/* Define the "inexact" versions in terms of the exact versions. */
+#define find_zero_low find_zero_all
+#define find_eq_low find_eq_all
+#define find_zero_eq_low find_zero_eq_all
+#define find_zero_ne_low find_zero_ne_all
+
+#endif /* _STRING_FZA_H */
diff --git a/sysdeps/alpha/string-fzb.h b/sysdeps/alpha/string-fzb.h
new file mode 100644
index 0000000000..e3934ba413
--- /dev/null
+++ b/sysdeps/alpha/string-fzb.h
@@ -0,0 +1,52 @@
+/* Zero byte detection; boolean. Alpha 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>
+
+/* Note that since CMPBGE creates a bit mask rather than a byte mask,
+ we cannot simply provide a target-specific string-fza.h. */
+
+/* Determine if any byte within X is zero. This is a pure boolean test. */
+
+static __always_inline _Bool
+has_zero (op_t x)
+{
+ return __builtin_alpha_cmpbge (0, x) != 0;
+}
+
+/* Likewise, but for byte equality between X1 and X2. */
+
+static __always_inline _Bool
+has_eq (op_t x1, op_t x2)
+{
+ return has_zero (x1 ^ x2);
+}
+
+/* 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)
+{
+ return has_zero (x1) | has_eq (x1, x2);
+}
+
+#endif /* _STRING_FZB_H */
diff --git a/sysdeps/alpha/string-fzi.h b/sysdeps/alpha/string-fzi.h
new file mode 100644
index 0000000000..aba7ca4f3d
--- /dev/null
+++ b/sysdeps/alpha/string-fzi.h
@@ -0,0 +1,62 @@
+/* string-fzi.h -- zero byte detection; indices. Alpha 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_FZI_H
+#define _STRING_FZI_H
+
+#include <stdint.h>
+#include <string-optype.h>
+#include <string-fza.h>
+
+/* Note that since CMPBGE creates a bit mask rather than a byte mask,
+ we cannot simply provide a target-specific string-fza.h. */
+
+/* A subroutine for the index_zero functions. Given a bitmask C,
+ return the index of the first bit set in memory order. */
+static __always_inline unsigned int
+index_first (find_t c)
+{
+#ifdef __alpha_cix__
+ return __builtin_ctzl (c);
+#else
+ c = c & -c;
+ return (c & 0xf0 ? 4 : 0) + (c & 0xcc ? 2 : 0) + (c & 0xaa ? 1 : 0);
+#endif
+}
+
+/* Similarly, but return the (memory order) index of the last bit
+ that is non-zero. Note that only the least 8 bits may be nonzero. */
+
+static __always_inline unsigned int
+index_last (find_t x)
+{
+#ifdef __alpha_cix__
+ return __builtin_clzl (x) ^ 63;
+#else
+ unsigned r = 0;
+ if (x & 0xf0)
+ r += 4;
+ if (x & (0xc << r))
+ r += 2;
+ if (x & (0x2 << r))
+ r += 1;
+ return r;
+#endif
+}
+
+#endif /* _STRING_FZI_H */
diff --git a/sysdeps/alpha/string-shift.h b/sysdeps/alpha/string-shift.h
new file mode 100644
index 0000000000..4e2cb2fea1
--- /dev/null
+++ b/sysdeps/alpha/string-shift.h
@@ -0,0 +1,44 @@
+/* Shift unaligned word read. Alpha 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_SHIFT_H
+#define _STRING_SHIFT_H 1
+
+#include <limits.h>
+#include <stdint.h>
+#include <string-fza.h>
+
+/* Return the mask WORD shifted based on S_INT address value, to ignore
+ values not presented in the aligned word read. */
+static __always_inline find_t
+shift_find (find_t word, uintptr_t s)
+{
+ return word >> (s % sizeof (op_t));
+}
+
+/* Mask off the bits defined the the S alignment value. */
+static __always_inline find_t
+shift_find_last (find_t word, uintptr_t s)
+{
+ s = s % sizeof (op_t);
+ if (s == 0)
+ return word;
+ return word & ~((op_t)-1 << s);
+}
+
+#endif /* _STRING_SHIFT_H */
--
2.34.1
next prev parent reply other threads:[~2023-02-02 18:12 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-02 18:11 [PATCH v12 00/31] Improve generic string routines Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 01/31] Parameterize op_t from memcopy.h Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 02/31] Parameterize OP_T_THRES " Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 03/31] Add string vectorized find and detection functions Adhemerval Zanella
2023-02-03 0:24 ` Richard Henderson
2023-02-03 12:39 ` Adhemerval Zanella Netto
2023-02-03 13:40 ` Adhemerval Zanella Netto
2023-02-04 2:54 ` Richard Henderson
2023-02-02 18:11 ` [PATCH v12 04/31] string: Improve generic strlen Adhemerval Zanella
2023-02-03 23:23 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 05/31] string: Improve generic strchrnul Adhemerval Zanella
2023-02-03 23:23 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 06/31] string: Improve generic strchr Adhemerval Zanella
2023-02-03 23:24 ` Noah Goldstein
2023-02-04 2:58 ` Richard Henderson
2023-02-06 13:07 ` Adhemerval Zanella Netto
2023-02-02 18:11 ` [PATCH v12 07/31] string: Improve generic strcmp Adhemerval Zanella
2023-02-03 23:25 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 08/31] string: Improve generic strncmp Adhemerval Zanella
2023-02-03 0:34 ` Richard Henderson
2023-02-21 9:28 ` Szabolcs Nagy
2023-02-21 12:24 ` Adhemerval Zanella Netto
2023-02-02 18:11 ` [PATCH v12 09/31] string: Improve generic stpcpy Adhemerval Zanella
2023-02-03 23:26 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 10/31] string: Improve generic strcpy Adhemerval Zanella
2023-02-03 23:26 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 11/31] string: Improve generic memchr Adhemerval Zanella
2023-02-03 23:26 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 12/31] string: Improve generic strnlen with memchr Adhemerval Zanella
2023-02-03 23:27 ` Noah Goldstein
2023-02-02 18:11 ` [PATCH v12 13/31] string: Improve generic memrchr Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 14/31] string: Improve generic strrchr with memrchr and strlen Adhemerval Zanella
2023-02-04 3:06 ` Richard Henderson
2023-02-06 14:01 ` Adhemerval Zanella Netto
2023-02-02 18:11 ` [PATCH v12 15/31] hppa: Add memcopy.h Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 16/31] hppa: Add string-fza.h, string-fzc.h, and string-fzi.h Adhemerval Zanella
2023-02-02 18:11 ` Adhemerval Zanella [this message]
2023-02-02 18:11 ` [PATCH v12 18/31] arm: Add string-fza.h Adhemerval Zanella
2023-02-20 13:24 ` Szabolcs Nagy
2023-02-20 13:45 ` Szabolcs Nagy
2023-02-20 14:01 ` Adhemerval Zanella Netto
2023-02-20 16:12 ` Szabolcs Nagy
2023-02-02 18:11 ` [PATCH v12 19/31] powerpc: " Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 20/31] sh: Add string-fzb.h Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 21/31] riscv: Add string-fza.h and string-fzi.h Adhemerval Zanella
2023-02-03 19:47 ` Noah Goldstein
2023-02-06 16:14 ` Adhemerval Zanella Netto
2023-02-02 18:11 ` [PATCH v12 22/31] string: Hook up the default implementation on test-strlen Adhemerval Zanella
2023-02-03 23:30 ` Noah Goldstein
2023-02-06 17:36 ` Adhemerval Zanella Netto
2023-02-02 18:11 ` [PATCH v12 23/31] string: Hook up the default implementation on test-strnlen Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 24/31] string: Hook up the default implementation on test-strchr Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 25/31] string: Hook up the default implementation on test-strcmp Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 26/31] string: Hook up the default implementation on test-strncmp Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 27/31] string: Hook up the default implementation on test-stpcpy Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 28/31] string: Hook up the default implementation on test-strcpy Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 29/31] string: Hook up the default implementation on test-memchr Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 30/31] string: Hook up the default implementation on test-memrchr Adhemerval Zanella
2023-02-02 18:11 ` [PATCH v12 31/31] string: Hook up the default implementation on test-strrchr Adhemerval Zanella
2023-02-03 1:55 ` Richard Henderson
2023-02-02 18:17 ` [PATCH v12 00/31] Improve generic string routines Adhemerval Zanella Netto
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