Add libc optimizations to bionic for MIPS
Test: Used bionic tests available under bionic/tests folder.
Tested for mips32r1/mips32r2/mips64r6 on emulators.
Change-Id: I589415ddc496df3f6067ae34cb33ca58b3a1f276
Signed-off-by: Prashant Patil <prashant.patil@imgtec.com>
diff --git a/libc/arch-mips/string/strlen.c b/libc/arch-mips/string/strlen.c
index 488e3c8..491efae 100644
--- a/libc/arch-mips/string/strlen.c
+++ b/libc/arch-mips/string/strlen.c
@@ -1,43 +1,115 @@
-/* $OpenBSD: strlen.c,v 1.8 2014/06/10 04:17:37 deraadt Exp $ */
-
-/*-
- * Copyright (c) 1990, 1993
- * The Regents of the University of California. All rights reserved.
+/*
+ * Copyright (c) 2017 Imagination Technologies.
+ *
+ * All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
*
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with
+ * the distribution.
+ * * Neither the name of Imagination Technologies nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <string.h>
-size_t
-strlen(const char *str) __overloadable
-{
- const char *s;
+#define op_t unsigned long int
+#define op_size sizeof (op_t)
- for (s = str; *s; ++s)
- ;
- return (s - str);
+#if __mips64 || __mips_isa_rev >= 2
+static inline size_t __attribute__ ((always_inline))
+do_bytes (const char *base, const char *p, op_t inval)
+{
+ op_t outval = 0;
+#if __mips64
+ __asm__ volatile (
+ "dsbh %1, %0 \n\t"
+ "dshd %0, %1 \n\t"
+ "dclz %1, %0 \n\t"
+ : "+r" (inval), "+r" (outval)
+ );
+#else
+ __asm__ volatile (
+ "wsbh %1, %0 \n\t"
+ "rotr %0, %1, 16 \n\t"
+ "clz %1, %0 \n\t"
+ : "+r" (inval), "+r" (outval)
+ );
+#endif
+ p += (outval >> 3);
+ return (size_t) (p - base);
}
+#define DO_WORD(w, cnt) { \
+ op_t val = ((w[cnt] - mask_1) & ~w[cnt]) & mask_128; \
+ if (val) \
+ return do_bytes(str, (const char *)(w + cnt), val); \
+}
+#else
+static inline size_t __attribute__ ((always_inline))
+do_bytes (const char *base, const char *p)
+{
+ for (; *p; ++p);
+ return (size_t) (p - base);
+}
+
+#define DO_WORD(w, cnt) { \
+ if (((w[cnt] - mask_1) & ~w[cnt]) & mask_128) \
+ return do_bytes(str, (const char *)(w + cnt)); \
+}
+#endif
+
+size_t
+strlen (const char *str) __overloadable
+{
+ if (*str) {
+ const char *p = (const char *) str;
+ const op_t *w;
+ op_t mask_1, mask_128;
+
+ while ((size_t) p % sizeof (op_t)) {
+ if (!(*p))
+ return (p - str);
+ p++;
+ }
+
+ __asm__ volatile (
+ "li %0, 0x01010101 \n\t"
+ : "=r" (mask_1)
+ );
+#if __mips64
+ mask_1 |= mask_1 << 32;
+#endif
+ mask_128 = mask_1 << 7;
+
+ w = (const op_t *) p;
+
+ while (1) {
+ DO_WORD(w, 0);
+ DO_WORD(w, 1);
+ DO_WORD(w, 2);
+ DO_WORD(w, 3);
+ w += 4;
+ }
+ }
+ return 0;
+}