1 files changed, 169 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/stringloops/memcmp.c b/tools/testing/selftests/powerpc/stringloops/memcmp.c
new file mode 100644
index 000000000..cb2f18855
--- /dev/null
+++ b/tools/testing/selftests/powerpc/stringloops/memcmp.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <malloc.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <time.h>
+
+#include "utils.h"
+
+#define SIZE 256
+#define ITERATIONS 10000
+
+#define LARGE_SIZE (5 * 1024)
+#define LARGE_ITERATIONS 1000
+#define LARGE_MAX_OFFSET 32
+#define LARGE_SIZE_START 4096
+
+/* This is big enough to fit LARGE_SIZE and works on 4K & 64K kernels */
+#define MAP_SIZE (64 * 1024)
+
+#define MAX_OFFSET_DIFF_S1_S2 48
+
+int vmx_count;
+int enter_vmx_ops(void)
+{
+	vmx_count++;
+	return 1;
+}
+
+void exit_vmx_ops(void)
+{
+	vmx_count--;
+}
+int test_memcmp(const void *s1, const void *s2, size_t n);
+
+/* test all offsets and lengths */
+static void test_one(char *s1, char *s2, unsigned long max_offset,
+		unsigned long size_start, unsigned long max_size)
+{
+	unsigned long offset, size;
+
+	for (offset = 0; offset < max_offset; offset++) {
+		for (size = size_start; size < (max_size - offset); size++) {
+			int x, y;
+			unsigned long i;
+
+			y = memcmp(s1+offset, s2+offset, size);
+			x = test_memcmp(s1+offset, s2+offset, size);
+
+			if (((x ^ y) < 0) &&	/* Trick to compare sign */
+				((x | y) != 0)) { /* check for zero */
+				printf("memcmp returned %d, should have returned %d (offset %ld size %ld)\n", x, y, offset, size);
+
+				for (i = offset; i < offset+size; i++)
+					printf("%02x ", s1[i]);
+				printf("\n");
+
+				for (i = offset; i < offset+size; i++)
+					printf("%02x ", s2[i]);
+				printf("\n");
+				abort();
+			}
+
+			if (vmx_count != 0) {
+				printf("vmx enter/exit not paired.(offset:%ld size:%ld s1:%p s2:%p vc:%d\n",
+					offset, size, s1, s2, vmx_count);
+				printf("\n");
+				abort();
+			}
+		}
+	}
+}
+
+static int testcase(bool islarge)
+{
+	unsigned long i, comp_size, alloc_size;
+	char *p, *s1, *s2;
+	int iterations;
+
+	comp_size = (islarge ? LARGE_SIZE : SIZE);
+	alloc_size = comp_size + MAX_OFFSET_DIFF_S1_S2;
+	iterations = islarge ? LARGE_ITERATIONS : ITERATIONS;
+
+	p = mmap(NULL, 4 * MAP_SIZE, PROT_READ | PROT_WRITE,
+		 MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	FAIL_IF(p == MAP_FAILED);
+
+	/* Put s1/s2 at the end of a page */
+	s1 = p + MAP_SIZE - alloc_size;
+	s2 = p + 3 * MAP_SIZE - alloc_size;
+
+	/* And unmap the subsequent page to force a fault if we overread */
+	munmap(p + MAP_SIZE, MAP_SIZE);
+	munmap(p + 3 * MAP_SIZE, MAP_SIZE);
+
+	srandom(time(0));
+
+	for (i = 0; i < iterations; i++) {
+		unsigned long j;
+		unsigned long change;
+		char *rand_s1 = s1;
+		char *rand_s2 = s2;
+
+		for (j = 0; j < alloc_size; j++)
+			s1[j] = random();
+
+		rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2;
+		rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2;
+		memcpy(rand_s2, rand_s1, comp_size);
+
+		/* change one byte */
+		change = random() % comp_size;
+		rand_s2[change] = random() & 0xff;
+
+		if (islarge)
+			test_one(rand_s1, rand_s2, LARGE_MAX_OFFSET,
+					LARGE_SIZE_START, comp_size);
+		else
+			test_one(rand_s1, rand_s2, SIZE, 0, comp_size);
+	}
+
+	srandom(time(0));
+
+	for (i = 0; i < iterations; i++) {
+		unsigned long j;
+		unsigned long change;
+		char *rand_s1 = s1;
+		char *rand_s2 = s2;
+
+		for (j = 0; j < alloc_size; j++)
+			s1[j] = random();
+
+		rand_s1 += random() % MAX_OFFSET_DIFF_S1_S2;
+		rand_s2 += random() % MAX_OFFSET_DIFF_S1_S2;
+		memcpy(rand_s2, rand_s1, comp_size);
+
+		/* change multiple bytes, 1/8 of total */
+		for (j = 0; j < comp_size / 8; j++) {
+			change = random() % comp_size;
+			s2[change] = random() & 0xff;
+		}
+
+		if (islarge)
+			test_one(rand_s1, rand_s2, LARGE_MAX_OFFSET,
+					LARGE_SIZE_START, comp_size);
+		else
+			test_one(rand_s1, rand_s2, SIZE, 0, comp_size);
+	}
+
+	return 0;
+}
+
+static int testcases(void)
+{
+#ifdef __powerpc64__
+	// vcmpequd used in memcmp_64.S is v2.07
+	SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_2_07));
+#endif
+
+	testcase(0);
+	testcase(1);
+	return 0;
+}
+
+int main(void)
+{
+	test_harness_set_timeout(300);
+	return test_harness(testcases, "memcmp");
+}