tests/tcg/s390x: Fix EXRL tests

The current EXRL tests crash on real machines: we must not use r0 as a base
register for trt/trtr, otherwise the content gets ignored. Also, we must
not use r0 for exrl, otherwise it gets ignored.

Let's use the "a" constraint so we get a general purpose register != r0.
For op2, we can simply specify a memory operand directly via "Q" (Memory
reference without index register and with short displacement).

Fixes: ad8c851d2e ("target/s390x: add EX support for TRT and TRTR")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210111163845.18148-5-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

tests/tcg/s390x/exrl-trt.c

@@ -19,7 +19,7 @@ int main(void)
     }
     asm volatile(
         "    j 2f\n"
-        "1:  trt 0(1,%[op1]),0(%[op2])\n"
+        "1:  trt 0(1,%[op1]),%[op2]\n"
         "2:  exrl %[op1_len],1b\n"
         "    lgr %[r1],%%r1\n"
         "    lgr %[r2],%%r2\n"
@@ -27,9 +27,9 @@ int main(void)
         : [r1] "+r" (r1),
           [r2] "+r" (r2),
           [cc] "=r" (cc)
-        : [op1] "r" (&op1),
-          [op1_len] "r" (5),
-          [op2] "r" (&op2)
+        : [op1] "a" (&op1),
+          [op1_len] "a" (5),
+          [op2] "Q" (op2)
         : "r1", "r2", "cc");
     cc = (cc >> 28) & 3;
     if (cc != 2) {

tests/tcg/s390x/exrl-trtr.c

@@ -19,7 +19,7 @@ int main(void)
     }
     asm volatile(
         "    j 2f\n"
-        "1:  trtr 3(1,%[op1]),0(%[op2])\n"
+        "1:  trtr 3(1,%[op1]),%[op2]\n"
         "2:  exrl %[op1_len],1b\n"
         "    lgr %[r1],%%r1\n"
         "    lgr %[r2],%%r2\n"
@@ -27,9 +27,9 @@ int main(void)
         : [r1] "+r" (r1),
           [r2] "+r" (r2),
           [cc] "=r" (cc)
-        : [op1] "r" (&op1),
-          [op1_len] "r" (3),
-          [op2] "r" (&op2)
+        : [op1] "a" (&op1),
+          [op1_len] "a" (3),
+          [op2] "Q" (op2)
         : "r1", "r2", "cc");
     cc = (cc >> 28) & 3;
     if (cc != 1) {