tests/tcg/s390x: Test VSTRS

Add a small test to prevent regressions.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230804233748.218935-4-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/tcg/s390x/Makefile.target

@@ -75,6 +75,7 @@ ifneq ($(CROSS_CC_HAS_Z15),)
 Z15_TESTS=vxeh2_vs
 Z15_TESTS+=vxeh2_vcvt
 Z15_TESTS+=vxeh2_vlstr
+Z15_TESTS+=vxeh2_vstrs
 $(Z15_TESTS): CFLAGS+=-march=z15 -O2
 TESTS+=$(Z15_TESTS)
 endif

tests/tcg/s390x/vxeh2_vstrs.c

@@ -0,0 +1,88 @@
+/*
+ * Test the VSTRS instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "vx.h"
+
+static inline __attribute__((__always_inline__)) int
+vstrs(S390Vector *v1, const S390Vector *v2, const S390Vector *v3,
+      const S390Vector *v4, const uint8_t m5, const uint8_t m6)
+{
+    int cc;
+
+    asm("vstrs %[v1],%[v2],%[v3],%[v4],%[m5],%[m6]\n"
+        "ipm %[cc]"
+        : [v1] "=v" (v1->v)
+        , [cc] "=r" (cc)
+        : [v2] "v" (v2->v)
+        , [v3] "v" (v3->v)
+        , [v4] "v" (v4->v)
+        , [m5] "i" (m5)
+        , [m6]  "i" (m6)
+        : "cc");
+
+    return (cc >> 28) & 3;
+}
+
+static void test_ignored_match(void)
+{
+    S390Vector v1;
+    S390Vector v2 = {.d[0] = 0x222000205e410000ULL, .d[1] = 0};
+    S390Vector v3 = {.d[0] = 0x205e410000000000ULL, .d[1] = 0};
+    S390Vector v4 = {.d[0] = 3, .d[1] = 0};
+
+    assert(vstrs(&v1, &v2, &v3, &v4, 0, 2) == 1);
+    assert(v1.d[0] == 16);
+    assert(v1.d[1] == 0);
+}
+
+static void test_empty_needle(void)
+{
+    S390Vector v1;
+    S390Vector v2 = {.d[0] = 0x5300000000000000ULL, .d[1] = 0};
+    S390Vector v3 = {.d[0] = 0, .d[1] = 0};
+    S390Vector v4 = {.d[0] = 0, .d[1] = 0};
+
+    assert(vstrs(&v1, &v2, &v3, &v4, 0, 0) == 2);
+    assert(v1.d[0] == 0);
+    assert(v1.d[1] == 0);
+}
+
+static void test_max_length(void)
+{
+    S390Vector v1;
+    S390Vector v2 = {.d[0] = 0x1122334455667700ULL, .d[1] = 0};
+    S390Vector v3 = {.d[0] = 0, .d[1] = 0};
+    S390Vector v4 = {.d[0] = 16, .d[1] = 0};
+
+    assert(vstrs(&v1, &v2, &v3, &v4, 0, 0) == 3);
+    assert(v1.d[0] == 7);
+    assert(v1.d[1] == 0);
+}
+
+static void test_no_match(void)
+{
+    S390Vector v1;
+    S390Vector v2 = {.d[0] = 0xffffff000fffff00ULL, .d[1] = 0x82b};
+    S390Vector v3 = {.d[0] = 0xfffffffeffffffffULL,
+                     .d[1] = 0xffffffff00000000ULL};
+    S390Vector v4 = {.d[0] = 11, .d[1] = 0};
+
+    assert(vstrs(&v1, &v2, &v3, &v4, 0, 2) == 1);
+    assert(v1.d[0] == 16);
+    assert(v1.d[1] == 0);
+}
+
+int main(void)
+{
+    test_ignored_match();
+    test_empty_needle();
+    test_max_length();
+    test_no_match();
+    return EXIT_SUCCESS;
+}