tests/tcg/s390x: Test LAALG with negative cc_src

Add a small test to prevent regressions.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231106093605.1349201-5-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
(cherry picked from commit ebc1410)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
(Mjt: context fix in tests/tcg/s390x/Makefile.target)

tests/tcg/s390x/Makefile.target

@@ -24,6 +24,7 @@ TESTS+=trap
 TESTS+=signals-s390x
 TESTS+=branch-relative-long
 TESTS+=noexec
+TESTS+=laalg
 
 Z13_TESTS=vistr
 Z13_TESTS+=lcbb

tests/tcg/s390x/laalg.c

@@ -0,0 +1,27 @@
+/*
+ * Test the LAALG instruction.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdlib.h>
+
+int main(void)
+{
+    unsigned long cc = 0, op1, op2 = 40, op3 = 2;
+
+    asm("slgfi %[cc],1\n"  /* Set cc_src = -1. */
+        "laalg %[op1],%[op3],%[op2]\n"
+        "ipm %[cc]"
+        : [cc] "+r" (cc)
+        , [op1] "=r" (op1)
+        , [op2] "+T" (op2)
+        : [op3] "r" (op3)
+        : "cc");
+
+    assert(cc == 0xffffffff10ffffff);
+    assert(op1 == 40);
+    assert(op2 == 42);
+
+    return EXIT_SUCCESS;
+}