3 files changed, 151 insertions, 1 deletions

diff --git a/tools/testing/selftests/powerpc/stringloops/Makefile b/tools/testing/selftests/powerpc/stringloops/Makefile
index b682be18dc66..31499587b483 100644
--- a/tools/testing/selftests/powerpc/stringloops/Makefile
+++ b/tools/testing/selftests/powerpc/stringloops/Makefile
@@ -6,7 +6,7 @@ EXTRA_SOURCES := ../harness.c
 
 build_32bit = $(shell if ($(CC) $(CFLAGS) -m32 -o /dev/null memcmp.c >/dev/null 2>&1) then echo "1"; fi)
 
-TEST_GEN_PROGS := memcmp_64
+TEST_GEN_PROGS := memcmp_64 strlen
 
 $(OUTPUT)/memcmp_64: memcmp.c
 $(OUTPUT)/memcmp_64: CFLAGS += -m64 -maltivec
@@ -18,6 +18,8 @@ $(OUTPUT)/memcmp_32: CFLAGS += -m32
 TEST_GEN_PROGS += memcmp_32
 endif
 
+$(OUTPUT)/strlen: strlen.c string.c
+
 ASFLAGS = $(CFLAGS)
 
 include ../../lib.mk
diff --git a/tools/testing/selftests/powerpc/stringloops/string.c b/tools/testing/selftests/powerpc/stringloops/string.c
new file mode 100644
index 000000000000..45e7775415c7
--- /dev/null
+++ b/tools/testing/selftests/powerpc/stringloops/string.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copied from linux/lib/string.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ */
+
+#include <stddef.h>
+
+/**
+ * strlen - Find the length of a string
+ * @s: The string to be sized
+ */
+size_t test_strlen(const char *s)
+{
+        const char *sc;
+
+        for (sc = s; *sc != '\0'; ++sc)
+                /* nothing */;
+        return sc - s;
+}
diff --git a/tools/testing/selftests/powerpc/stringloops/strlen.c b/tools/testing/selftests/powerpc/stringloops/strlen.c
new file mode 100644
index 000000000000..9055ebc484d0
--- /dev/null
+++ b/tools/testing/selftests/powerpc/stringloops/strlen.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <malloc.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "utils.h"
+
+#define SIZE 256
+#define ITERATIONS 1000
+#define ITERATIONS_BENCH 100000
+
+int test_strlen(const void *s);
+
+/* test all offsets and lengths */
+static void test_one(char *s)
+{
+        unsigned long offset;
+
+        for (offset = 0; offset < SIZE; offset++) {
+                int x, y;
+                unsigned long i;
+
+                y = strlen(s + offset);
+                x = test_strlen(s + offset);
+
+                if (x != y) {
+                        printf("strlen() returned %d, should have returned %d (%p offset %ld)\n", x, y, s, offset);
+
+                        for (i = offset; i < SIZE; i++)
+                                printf("%02x ", s[i]);
+                        printf("\n");
+                }
+        }
+}
+
+static void bench_test(char *s)
+{
+        struct timespec ts_start, ts_end;
+        int i;
+
+        clock_gettime(CLOCK_MONOTONIC, &ts_start);
+
+        for (i = 0; i < ITERATIONS_BENCH; i++)
+                test_strlen(s);
+
+        clock_gettime(CLOCK_MONOTONIC, &ts_end);
+
+        printf("len %3.3d : time = %.6f\n", test_strlen(s), ts_end.tv_sec - ts_start.tv_sec + (ts_end.tv_nsec - ts_start.tv_nsec) / 1e9);
+}
+
+static int testcase(void)
+{
+        char *s;
+        unsigned long i;
+
+        s = memalign(128, SIZE);
+        if (!s) {
+                perror("memalign");
+                exit(1);
+        }
+
+        srandom(1);
+
+        memset(s, 0, SIZE);
+        for (i = 0; i < SIZE; i++) {
+                char c;
+
+                do {
+                        c = random() & 0x7f;
+                } while (!c);
+                s[i] = c;
+                test_one(s);
+        }
+
+        for (i = 0; i < ITERATIONS; i++) {
+                unsigned long j;
+
+                for (j = 0; j < SIZE; j++) {
+                        char c;
+
+                        do {
+                                c = random() & 0x7f;
+                        } while (!c);
+                        s[j] = c;
+                }
+                for (j = 0; j < sizeof(long); j++) {
+                        s[SIZE - 1 - j] = 0;
+                        test_one(s);
+                }
+        }
+
+        for (i = 0; i < SIZE; i++) {
+                char c;
+
+                do {
+                        c = random() & 0x7f;
+                } while (!c);
+                s[i] = c;
+        }
+
+        bench_test(s);
+
+        s[16] = 0;
+        bench_test(s);
+
+        s[8] = 0;
+        bench_test(s);
+
+        s[4] = 0;
+        bench_test(s);
+
+        s[3] = 0;
+        bench_test(s);
+
+        s[2] = 0;
+        bench_test(s);
+
+        s[1] = 0;
+        bench_test(s);
+
+        return 0;
+}
+
+int main(void)
+{
+        return test_harness(testcase, "strlen");
+}