Generalize gdb.reverse/aarch64.exp

I said we can generialize gdb.reverse/aarch64.exp for other
architectures https://sourceware.org/ml/gdb-patches/2015-05/msg00482.html
and here is the patch to change aarch64.exp so that it can be used to
test for other architectures as well.

gdb/testsuite:

2016-02-26  Yao Qi  <yao.qi@linaro.org>

	* gdb.reverse/aarch64.c: [__aarch64__] Include arm_neon.h.
	(testcase_ftype): New.
	(testcases): New array.
	(n_testcases): New.
	(main): Call each element in testcases.
	* gdb.reverse/aarch64.exp: Remove is_aarch64_target check.
	(read_testcase): New.
	Do the tests in a loop.

gdb/testsuite/ChangeLog

@@ -1,3 +1,14 @@
+2016-02-26  Yao Qi  <yao.qi@linaro.org>
+
+	* gdb.reverse/aarch64.c: [__aarch64__] Include arm_neon.h.
+	(testcase_ftype): New.
+	(testcases): New array.
+	(n_testcases): New.
+	(main): Call each element in testcases.
+	* gdb.reverse/aarch64.exp: Remove is_aarch64_target check.
+	(read_testcase): New.
+	Do the tests in a loop.
+
 2016-02-25  Yao Qi  <yao.qi@linaro.org>
 
 	* gdb.base/branches.c: Remove.

gdb/testsuite/gdb.reverse/aarch64.c

@@ -15,8 +15,11 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+#if (defined __aarch64__)
 #include <arm_neon.h>
+#endif
 
+#if (defined __aarch64__)
 static void
 load (void)
 {
@@ -85,15 +88,34 @@ adv_simd_vect_shift (void)
 {
   asm ("fcvtzs s0, s0, #1");
 }
+#endif
+
+typedef void (*testcase_ftype) (void);
+
+/* Functions testing instruction decodings.  GDB will read n_testcases
+   to know how many functions to test.  */
+
+static testcase_ftype testcases[] =
+{
+#if (defined __aarch64__)
+  load,
+  move,
+  adv_simd_mod_imm,
+  adv_simd_scalar_index,
+  adv_simd_smlal,
+  adv_simd_vect_shift,
+#endif
+};
+
+static int n_testcases = (sizeof (testcases) / sizeof (testcase_ftype));
 
 int
 main ()
 {
-  load ();
+  int i = 0;
-  move ();
+
-  adv_simd_mod_imm ();
+  for (i = 0; i < n_testcases; i++)
-  adv_simd_scalar_index ();
+    testcases[i] ();
-  adv_simd_smlal ();
+
-  adv_simd_vect_shift ();
   return 0;
 }

gdb/testsuite/gdb.reverse/aarch64.exp

@@ -17,13 +17,6 @@ if ![supports_reverse] {
     return
 }
 
-# Test aarch64 instruction recording.
-
-if {![is_aarch64_target]} then {
-    verbose "Skipping aarch64 instruction recording tests."
-    return
-}
-
 standard_testfile
 
 if {[prepare_for_testing $testfile.exp $testfile $srcfile \
@@ -36,6 +29,22 @@ if { ![runto main] } then {
     return
 }
 
+# Read function name from testcases[N].
+
+proc read_testcase { n } {
+    global gdb_prompt
+
+    set result -1
+    gdb_test_multiple "print testcases\[${n}\]" "read name of test case ${n}" {
+	-re "\[$\].*= .*<(.*)>.*$gdb_prompt $" {
+	    set result $expect_out(1,string)
+	}
+	-re "$gdb_prompt $" { }
+    }
+
+    return $result
+}
+
 # In each function FUNC, GDB turns on process record, and single step
 # until program goes to the end of the function.  Then, single step
 # backward.  In each of forward single step and backward single step,
@@ -107,9 +116,15 @@ proc test { func } {
     }
 }
 
-test "load"
+set n_testcases [get_integer_valueof "n_testcases" 0]
-test "move"
+
-test "adv_simd_mod_imm"
+if { ${n_testcases} == 0 } {
-test "adv_simd_scalar_index"
+    untested "No test"
-test "adv_simd_smlal"
+    return 1
-test "adv_simd_vect_shift"
+}
+
+for { set i 0 } { ${i} < ${n_testcases} } { incr i } {
+    set testcase [read_testcase $i]
+
+    test $testcase
+}