[v3,17/18] powerpc: Add string-fza.h
Commit Message
From: Richard Henderson <rth@twiddle.net>
While ppc has the more important string functions in assembly,
there are still a few generic routines used.
Use the Power 6 CMPB insn for testing of zeros.
Checked on powerpc64le-linux-gnu.
Richard Henderson <rth@twiddle.net>
* sysdeps/powerpc/power6/string-fza.h: New file.
* sysdeps/powerpc/powerpc32/power6/string-fza.h: Likewise.
* sysdeps/powerpc/powerpc64/power6/string-fza.h: Likewise.
---
sysdeps/powerpc/power6/string-fza.h | 65 +++++++++++++++++++++++++++
sysdeps/powerpc/powerpc32/power6/string-fza.h | 1 +
sysdeps/powerpc/powerpc64/power6/string-fza.h | 1 +
3 files changed, 67 insertions(+)
create mode 100644 sysdeps/powerpc/power6/string-fza.h
create mode 100644 sysdeps/powerpc/powerpc32/power6/string-fza.h
create mode 100644 sysdeps/powerpc/powerpc64/power6/string-fza.h
Comments
Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:
> From: Richard Henderson <rth@twiddle.net>
>
> While ppc has the more important string functions in assembly,
> there are still a few generic routines used.
>
> Use the Power 6 CMPB insn for testing of zeros.
>
> Checked on powerpc64le-linux-gnu.
>
> Richard Henderson <rth@twiddle.net>
>
> * sysdeps/powerpc/power6/string-fza.h: New file.
> * sysdeps/powerpc/powerpc32/power6/string-fza.h: Likewise.
> * sysdeps/powerpc/powerpc64/power6/string-fza.h: Likewise.
From my reply in Dec. 2016: ;-)
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Thanks!
new file mode 100644
@@ -0,0 +1,65 @@
+/* Zero byte detection; basics. Power6/ISA 2.03 version.
+ 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/>. */
+
+#ifndef STRING_FZA_H
+#define STRING_FZA_H 1
+
+#include <string-optype.h>
+
+/* This function returns 0xff for each byte that is
+ equal between X1 and X2. */
+
+static inline op_t
+find_eq_all (op_t x1, op_t x2)
+{
+ op_t ret;
+ asm ("cmpb %0,%1,%2" : "=r"(ret) : "r"(x1), "r"(x2));
+ return ret;
+}
+
+/* This function returns 0xff for each byte that is zero in X. */
+
+static inline op_t
+find_zero_all (op_t x)
+{
+ return find_eq_all (x, 0);
+}
+
+/* Identify zero bytes in X1 or equality between X1 and X2. */
+
+static inline op_t
+find_zero_eq_all (op_t x1, op_t x2)
+{
+ return find_zero_all (x1) | find_eq_all (x1, x2);
+}
+
+/* Identify zero bytes in X1 or inequality between X1 and X2. */
+
+static inline op_t
+find_zero_ne_all (op_t x1, op_t x2)
+{
+ return find_zero_all (x1) | ~find_eq_all (x1, x2);
+}
+
+/* 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 */
new file mode 100644
@@ -0,0 +1 @@
+#include <sysdeps/powerpc/power6/string-fza.h>
new file mode 100644
@@ -0,0 +1 @@
+#include <sysdeps/powerpc/power6/string-fza.h>