Move step_until procedure

Procedure step_until from test gdb.reverse/step-indirect-call-thunk.exp
is moved to lib/gdb.exp and renamed repeat_cmd_until.  The existing procedure
gdb_step_until in lib/gdb.exp is simpler variant of the new repeat_cmd_until
procedure.  The existing procedure gdb_step_until is changed to just call
the new repeat_cmd_until procedure with the command set to "step" and an
optional CURRENT string.  The default CURRENT string is set to "\}" to work
with the existing uses of procedure gdb_step_until.

gdb/testsuite/gdb.reverse/step-indirect-call-thunk.exp

@@ -38,39 +38,6 @@ if { ![runto_main] } {
     return -1
 }
 
-# Do repeated stepping COMMANDs in order to reach TARGET from CURRENT
-#
-#  COMMAND is a stepping command
-#  CURRENT is a string matching the current location
-#  TARGET  is a string matching the target location
-#  TEST    is the test name
-#
-# The function issues repeated COMMANDs as long as the location matches
-# CURRENT up to a maximum of 100 steps.
-#
-# TEST passes if the resulting location matches TARGET and fails
-# otherwise.
-#
-proc step_until { command current target test } {
-    global gdb_prompt
-
-    set count 0
-    gdb_test_multiple "$command" "$test" {
-        -re "$current.*$gdb_prompt $" {
-            incr count
-            if { $count < 100 } {
-                send_gdb "$command\n"
-                exp_continue
-            } else {
-                fail "$test"
-            }
-        }
-        -re "$target.*$gdb_prompt $" {
-            pass "$test"
-        }
-    }
-}
-
 gdb_test_no_output "record"
 gdb_test "next" ".*" "record trace"
 
@@ -90,20 +57,20 @@ gdb_test "reverse-next" "apply\.2.*" \
     "reverse-step through thunks and over inc"
 
 # We can use instruction stepping to step into thunks.
-step_until "stepi" "apply\.2" "indirect_thunk" "stepi into call thunk"
-step_until "stepi" "indirect_thunk" "inc" \
+repeat_cmd_until "stepi" "apply\.2" "indirect_thunk" "stepi into call thunk"
+repeat_cmd_until "stepi" "indirect_thunk" "inc" \
     "stepi out of call thunk into inc"
 set alphanum_re "\[a-zA-Z0-9\]"
 set pic_thunk_re  "__$alphanum_re*\\.get_pc_thunk\\.$alphanum_re* \\(\\)"
-step_until "stepi" "(inc|$pic_thunk_re)" "return_thunk" "stepi into return thunk"
-step_until "stepi" "return_thunk" "apply" \
+repeat_cmd_until "stepi" "(inc|$pic_thunk_re)" "return_thunk" "stepi into return thunk"
+repeat_cmd_until "stepi" "return_thunk" "apply" \
     "stepi out of return thunk back into apply"
 
-step_until "reverse-stepi" "apply" "return_thunk" \
+repeat_cmd_until "reverse-stepi" "apply" "return_thunk" \
     "reverse-stepi into return thunk"
-step_until "reverse-stepi" "return_thunk" "inc" \
+repeat_cmd_until "reverse-stepi" "return_thunk" "inc" \
     "reverse-stepi out of return thunk into inc"
-step_until "reverse-stepi" "(inc|$pic_thunk_re)" "indirect_thunk" \
+repeat_cmd_until "reverse-stepi" "(inc|$pic_thunk_re)" "indirect_thunk" \
     "reverse-stepi into call thunk"
-step_until "reverse-stepi" "indirect_thunk" "apply" \
+repeat_cmd_until "reverse-stepi" "indirect_thunk" "apply" \
     "reverse-stepi out of call thunk into apply"

gdb/testsuite/lib/gdb.exp

@@ -9347,31 +9347,50 @@ gdb_caching_proc arm_cc_for_target {} {
 
 # Step until the pattern REGEXP is found.  Step at most
 # MAX_STEPS times, but stop stepping once REGEXP is found.
-#
+# CURRENT matches current location
 # If REGEXP is found then a single pass is emitted, otherwise, after
 # MAX_STEPS steps, a single fail is emitted.
 #
 # TEST_NAME is the name used in the pass/fail calls.
 
-proc gdb_step_until { regexp {test_name ""} {max_steps 10} } {
-    if { $test_name == "" } {
-	set test_name "stepping until regexp"
-    }
+proc gdb_step_until { regexp {test_name "stepping until regexp"} \
+			  {current "\}"} { max_steps 10 } } {
+    repeat_cmd_until "step" $current  $regexp  $test_name "10"
+}
+
+# Do repeated stepping COMMANDs in order to reach TARGET from CURRENT
+#
+#  COMMAND   is a stepping command
+#  CURRENT   is a string matching the current location
+#  TARGET    is a string matching the target location
+#  TEST_NAME is the test name
+#  MAX_STEPS is number of steps attempted before fail is emitted
+#
+# The function issues repeated COMMANDs as long as the location matches
+# CURRENT up to a maximum of MAX_STEPS.
+#
+# TEST_NAME passes if the resulting location matches TARGET and fails
+# otherwise.
+
+proc repeat_cmd_until { command current target \
+			    {test_name "stepping until regexp"} \
+			    {max_steps 100} } {
+    global gdb_prompt
 
     set count 0
-    gdb_test_multiple "step" "$test_name" {
-	-re "$regexp\r\n$::gdb_prompt $" {
-	    pass $test_name
-	}
-	-re ".*$::gdb_prompt $" {
-	    if {$count < $max_steps} {
-		incr count
-		send_gdb "step\n"
+    gdb_test_multiple "$command" "$test_name" {
+	-re "$current.*$gdb_prompt $" {
+	    incr count
+	    if { $count < $max_steps } {
+		send_gdb "$command\n"
 		exp_continue
 	    } else {
-		fail $test_name
+		fail "$test_name"
 	    }
 	}
+	-re "$target.*$gdb_prompt $" {
+	    pass "$test_name"
+	}
     }
 }