tests/tcg/s390x: Test LCBB

Add a test to prevent regressions.

Cc: qemu-stable@nongnu.org
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230526181240.1425579-3-iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
(cherry picked from commit 05d000f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

tests/tcg/s390x/Makefile.target

@@ -26,6 +26,7 @@ TESTS+=branch-relative-long
 TESTS+=noexec
 
 Z13_TESTS=vistr
+Z13_TESTS+=lcbb
 $(Z13_TESTS): CFLAGS+=-march=z13 -O2
 TESTS+=$(Z13_TESTS)
 

tests/tcg/s390x/lcbb.c

@@ -0,0 +1,51 @@
+/*
+ * Test the LCBB instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdlib.h>
+
+static inline __attribute__((__always_inline__)) void
+lcbb(long *r1, void *dxb2, int m3, int *cc)
+{
+    asm("lcbb %[r1],%[dxb2],%[m3]\n"
+        "ipm %[cc]"
+        : [r1] "+r" (*r1), [cc] "=r" (*cc)
+        : [dxb2] "R" (*(char *)dxb2), [m3] "i" (m3)
+        : "cc");
+    *cc = (*cc >> 28) & 3;
+}
+
+static char buf[0x1000] __attribute__((aligned(0x1000)));
+
+static inline __attribute__((__always_inline__)) void
+test_lcbb(void *p, int m3, int exp_r1, int exp_cc)
+{
+    long r1 = 0xfedcba9876543210;
+    int cc;
+
+    lcbb(&r1, p, m3, &cc);
+    assert(r1 == (0xfedcba9800000000 | exp_r1));
+    assert(cc == exp_cc);
+}
+
+int main(void)
+{
+    test_lcbb(&buf[0],    0, 16, 0);
+    test_lcbb(&buf[63],   0,  1, 3);
+    test_lcbb(&buf[0],    1, 16, 0);
+    test_lcbb(&buf[127],  1,  1, 3);
+    test_lcbb(&buf[0],    2, 16, 0);
+    test_lcbb(&buf[255],  2,  1, 3);
+    test_lcbb(&buf[0],    3, 16, 0);
+    test_lcbb(&buf[511],  3,  1, 3);
+    test_lcbb(&buf[0],    4, 16, 0);
+    test_lcbb(&buf[1023], 4,  1, 3);
+    test_lcbb(&buf[0],    5, 16, 0);
+    test_lcbb(&buf[2047], 5,  1, 3);
+    test_lcbb(&buf[0],    6, 16, 0);
+    test_lcbb(&buf[4095], 6,  1, 3);
+
+    return EXIT_SUCCESS;
+}