Add options to skip unavailable locals

This is the patch to add new option '--skip-unavailable' to MI
commands '-stack-list-{locals, arguments, variables}'.  This patch
extends list_args_or_locals to add a new parameter 'skip_unavailable',
and don't list locals or arguments if values are unavailable and
'skip_unavailable' is true.

This is inspecting a trace frame (tfind mode), where only a few
locals have been collected.

-stack-list-locals, no switch vs new switch:

 -stack-list-locals --simple-values
 ^done,locals=[{name="array",type="unsigned char [2]"},{name="i",type="int",value="<unavailable>"}]
 -stack-list-locals --skip-unavailable --simple-values
 ^done,locals=[{name="array",type="unsigned char [2]"}]

-stack-list-arguments, no switch vs new switch:

 -stack-list-arguments --simple-values
 ^done,stack-args=[frame={level="0",args=[{name="j",type="int",value="4"},{name="s",type="char *",value="<unavailable>"}]},frame={level="1",args=[]}]
 -stack-list-arguments --skip-unavailable --simple-values
 ^done,stack-args=[frame={level="0",args=[{name="j",type="int",value="4"}]},frame={level="1",args=[]}]

-stack-list-variables, no switch vs new switch:

 -stack-list-variables --simple-values
 ^done,variables=[{name="j",arg="1",type="int",value="4"},{name="s",arg="1",type="char *",value="<unavailable>"},{name="array",type="unsigned char [2]"},{name="i",type="int",value="<unavailable>"}]
 -stack-list-variables --skip-unavailable --simple-values
 ^done,variables=[{name="j",arg="1",type="int",value="4"},{name="array",type="unsigned char [2]"}]

tests are added to test these new options.

gdb:

2013-08-27  Pedro Alves  <pedro@codesourcery.com>
	    Yao Qi  <yao@codesourcery.com>

	* mi/mi-cmd-stack.c (list_args_or_locals): Adjust prototype.
	(parse_no_frames_option): Remove.
	(mi_cmd_stack_list_locals): Handle --skip-unavailable.
	(mi_cmd_stack_list_args): Adjust.
	(mi_cmd_stack_list_variables): Handle --skip-unavailable.
	(list_arg_or_local): Add new parameter 'skip_unavailable'.  Return
	early if SKIP_UNAVAILABLE is true and ARG->val is unavailable.
	Caller update.
	(list_args_or_locals): New parameter 'skip_unavailable'.
	Handle it.
	* valprint.c (scalar_type_p): Rename to ...
	(val_print_scalar_type_p): ... this.  Make extern.
	(val_print, value_check_printable): Adjust.
	* valprint.h (val_print_scalar_type_p): Declare.
	* value.c (value_entirely_unavailable): New function.
	* value.h (value_entirely_unavailable): Declare.

	* NEWS: Mention the new option "--skip-unavailable" to MI
	commands '-stack-list-locals', '-stack-list-arguments' and
	'-stack-list-variables'.

gdb/doc:

2013-08-27  Pedro Alves  <pedro@codesourcery.com>
	    Yao Qi  <yao@codesourcery.com>

	* gdb.texinfo (GDB/MI Stack Manipulation) <-stack-list-locals>:
	Document new --skip-unavailable option.
	<-stack-list-variables>: Document new --skip-unavailable option.

gdb/testsuite:

2013-08-27  Yao Qi  <yao@codesourcery.com>

	* gdb.trace/entry-values.exp: Test unavailable entry value is
	not shown when option '--skip-unavailable' is specified.
	* gdb.trace/mi-trace-unavailable.exp (test_trace_unavailable):
	Add tests for new option '--skip-unavailable'.

3 files changed, 21 insertions, 0 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index cbc4e6f..7467bb9 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,12 @@
 2013-08-27  Yao Qi  <yao@codesourcery.com>
 
+	* gdb.trace/entry-values.exp: Test unavailable entry value is
+	not shown when option '--skip-unavailable' is specified.
+	* gdb.trace/mi-trace-unavailable.exp (test_trace_unavailable):
+	Add tests for new option '--skip-unavailable'.
+
+2013-08-27  Yao Qi  <yao@codesourcery.com>
+
 	* lib/gdb.exp (gdb_remote_download): Don't pass $tofile to
 	remote_download if it is empty.
 
diff --git a/gdb/testsuite/gdb.trace/entry-values.exp b/gdb/testsuite/gdb.trace/entry-values.exp
index bb62e5d..85306ad 100644
--- a/gdb/testsuite/gdb.trace/entry-values.exp
+++ b/gdb/testsuite/gdb.trace/entry-values.exp
@@ -276,4 +276,9 @@ gdb_test "tfind" "Found trace frame 0, .*" "tfind start"
 # Since 'global2' is not collected, j@entry is expected to be 'unavailable'.
 gdb_test "bt 1" "#0 .* foo \\(i=\[-\]?$decimal, i@entry=2, j=\[-\]?$decimal, j@entry=<unavailable>\\).*"
 
+# Test that unavailable "j@entry" is not shown when command option
+# --skip-unavailable is used.
+gdb_test "interpreter-exec mi \"-stack-list-arguments --skip-unavailable --simple-values\"" \
+    "\r\n\\^done,stack-args=\\\[frame={level=\"0\",args=\\\[{name=\"i\",type=\"int\",value=\".*\"},{name=\"i@entry\",type=\"int\",value=\"2\"},{name=\"j\",type=\"int\",value=\".*\"}\\\]},frame=.*\\\].*"
+
 gdb_test "tfind" "Target failed to find requested trace frame\..*"
diff --git a/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp b/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
index d96ec8b..c69891b 100644
--- a/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
+++ b/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
@@ -106,16 +106,25 @@ proc test_trace_unavailable { data_source } {
 	mi_gdb_test "-stack-list-locals --simple-values" \
 	    ".*\\^done,locals=\\\[\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\},\{name=\"i\",type=\"int\",value=\"<unavailable>\"\}\\\]" \
 	    "-stack-list-locals --simple-values"
+	mi_gdb_test "-stack-list-locals --skip-unavailable --simple-values" \
+	    ".*\\^done,locals=\\\[\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\}\\\]" \
+	    "-stack-list-locals --skip-unavailable --simple-values"
 
 	# Test MI command '-stack-list-arguments'.
 	mi_gdb_test "-stack-list-arguments --simple-values" \
 	    ".*\\^done,stack-args=\\\[frame=\{level=\"0\",args=\\\[\{name=\"j\",type=\"int\",value=\"4\"\},\{name=\"s\",type=\"char \\\*\",value=\"<unavailable>\"\}\\\]\},.*\}.*" \
 	    "-stack-list-arguments --simple-values"
+	mi_gdb_test "-stack-list-arguments --skip-unavailable --simple-values" \
+	    ".*\\^done,stack-args=\\\[frame=\{level=\"0\",args=\\\[\{name=\"j\",type=\"int\",value=\"4\"\}\\\]\},.*\}.*" \
+	    "-stack-list-arguments --skip-unavailable --simple-values"
 
 	# Test MI command '-stack-list-variables'.
 	mi_gdb_test "-stack-list-variables --simple-values" \
 	    ".*\\^done,variables=\\\[\{name=\"j\",arg=\"1\",type=\"int\",value=\"4\"\},\{name=\"s\",arg=\"1\",type=\"char \\\*\",value=\"<unavailable>\"\},\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\},\{name=\"i\",type=\"int\",value=\"<unavailable>\"\}\\\]" \
 	    "-stack-list-variables --simple-values"
+	mi_gdb_test "-stack-list-variables --skip-unavailable --simple-values" \
+	    ".*\\^done,variables=\\\[\{name=\"j\",arg=\"1\",type=\"int\",value=\"4\"\},\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\}\\\]" \
+	    "-stack-list-variables --skip-unavailable --simple-values"
 
 	mi_gdb_test "-trace-find frame-number 1" \
 	    ".*\\^done,found=\"1\",tracepoint=\"${decimal}\",traceframe=\"1\",frame=\{.*" \