[PATCH 3/3] tests/tcg/s390x: Add a test for the vistr instruction

[Thomas Huth <thuth@redhat.com>]

This test can be used to verify that the change in the previous
commit is indeed fixing the problem with the M3 vs. M4 field
mixup.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tests/tcg/s390x/vistr.c         | 45 +++++++++++++++++++++++++++++++++
 tests/tcg/s390x/Makefile.target |  4 +++
 2 files changed, 49 insertions(+)
 create mode 100644 tests/tcg/s390x/vistr.c

diff --git a/tests/tcg/s390x/vistr.c b/tests/tcg/s390x/vistr.c
new file mode 100644
index 0000000000..8e3e987d71
--- /dev/null
+++ b/tests/tcg/s390x/vistr.c
@@ -0,0 +1,45 @@
+/*
+ * Test the VECTOR ISOLATE STRING (vistr) instruction
+ */
+#include <stdint.h>
+#include <stdio.h>
+#include "vx.h"
+
+static inline void vistr(S390Vector *v1, S390Vector *v2,
+                         const uint8_t m3, const uint8_t m5)
+{
+    asm volatile("vistr %[v1], %[v2], %[m3], %[m5]\n"
+                 : [v1] "=v" (v1->v)
+                 : [v2]  "v" (v2->v)
+                 , [m3]  "i" (m3)
+                 , [m5]  "i" (m5)
+                 : "cc");
+}
+
+int main(int argc, char *argv[])
+{
+    S390Vector vd = {};
+    S390Vector vs16 = {
+        .h[0] = 0x1234, .h[1] = 0x0056, .h[2] = 0x7800, .h[3] = 0x0000,
+        .h[4] = 0x0078, .h[5] = 0x0000, .h[6] = 0x6543, .h[7] = 0x2100
+    };
+    S390Vector vs32 = {
+        .w[0] = 0x12340000, .w[1] = 0x78654300,
+        .w[2] = 0x0, .w[3] = 0x12,
+    };
+
+    vistr(&vd, &vs16, 1, 0);
+    if (vd.h[0] != 0x1234 || vd.h[1] != 0x0056 || vd.h[2] != 0x7800 ||
+        vd.h[3] || vd.h[4] || vd.h[5] || vd.h[6] || vd.h[7]) {
+        puts("ERROR: vitrh failed!");
+        return 1;
+    }
+
+    vistr(&vd, &vs32, 2, 0);
+    if (vd.w[0] != 0x12340000 || vd.w[1] != 0x78654300 || vd.w[2] || vd.w[3]) {
+        puts("ERROR: vitrf failed!");
+        return 1;
+    }
+
+    return 0;
+}
diff --git a/tests/tcg/s390x/Makefile.target b/tests/tcg/s390x/Makefile.target
index 29c8af8207..07fcc6d0ce 100644
--- a/tests/tcg/s390x/Makefile.target
+++ b/tests/tcg/s390x/Makefile.target
@@ -25,6 +25,10 @@ TESTS+=signals-s390x
 TESTS+=branch-relative-long
 TESTS+=noexec
 
+Z13_TESTS=vistr
+$(Z13_TESTS): CFLAGS+=-march=z13 -O2
+TESTS+=$(Z13_TESTS)
+
 ifneq ($(CROSS_CC_HAS_Z14),)
 Z14_TESTS=vfminmax
 vfminmax: LDFLAGS+=-lm
-- 
2.31.1