[PATCH v2] Fix raw-frame-arguments in combination with frame-filters

[Hannes Domani <ssbssa@yahoo.de>]

Currently, if frame-filters are active, raw-values is used instead of
raw-frame-arguments to decide if a pretty-printer should be invoked for
frame arguments in a backtrace.

In this example, "super struct" is the output of the pretty-printer:

    (gdb) disable frame-filter global BasicFrameFilter
    (gdb) bt
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57

If no frame-filter is active, then the raw-values print option does not
affect the backtrace output:

    (gdb) set print raw-values on
    (gdb) bt
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57
    (gdb) set print raw-values off

Instead, the raw-frame-arguments option disables the pretty-printer in the
backtrace:

    (gdb) bt -raw-frame-arguments on
    #0  foo (x=42, ss=...) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57

But if a frame-filter is active, the same rules don't apply.
The option raw-frame-arguments is ignored, but raw-values decides if the
pretty-printer is used:

    (gdb) enable frame-filter global BasicFrameFilter
    (gdb) bt
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57
    (gdb) set print raw-values on
    (gdb) bt
    #0  foo (x=42, ss=...) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57
    (gdb) set print raw-values off
    (gdb) bt -raw-frame-arguments on
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57

So this adds the PRINT_RAW_FRAME_ARGUMENTS flag to frame_filter_flag, which
is then used in the frame-filter to override the raw flag in enumerate_args.

Then the output is the same if a frame-filter is active, the pretty-printer
for backtraces is only disabled with the raw-frame-arguments option:

    (gdb) enable frame-filter global BasicFrameFilter
    (gdb) bt
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57
    (gdb) set print raw-values on
    (gdb) bt
    #0  foo (x=42, ss=super struct = {...}) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57
    (gdb) set print raw-values off
    (gdb) bt -raw-frame-arguments on
    #0  foo (x=42, ss=...) at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:47
    #1  0x004016aa in main () at C:/src/repos/gdb-testsuite/gdb/testsuite/gdb.python/py-frame-args.c:57

gdb/ChangeLog:

2021-01-31  Hannes Domani  <ssbssa@yahoo.de>

	* extension.h (enum frame_filter_flag): Add
	PRINT_RAW_FRAME_ARGUMENTS.
	* python/py-framefilter.c (enumerate_args): Override raw flag.
	raw_frame_args argument.
	(py_mi_print_variables): Forward raw flag.
	(py_print_args): Forward raw_frame_args flag.
	(py_print_frame): Handle PRINT_RAW_FRAME_ARGUMENTS.
	* stack.c (backtrace_command_1): Set PRINT_RAW_FRAME_ARGUMENTS.

gdb/testsuite/ChangeLog:

2021-01-31  Hannes Domani  <ssbssa@yahoo.de>

	* gdb.python/py-frame-args.exp: Add bt raw-frame-arguments tests.
	* gdb.python/py-frame-args.py: Add basic frame-filter.
---
v2:
- More detailed commit message describing the problem.
---
 gdb/extension.h                            |  4 ++++
 gdb/python/py-framefilter.c                | 14 ++++++++++----
 gdb/stack.c                                |  2 ++
 gdb/testsuite/gdb.python/py-frame-args.exp | 20 ++++++++++++++++++++
 gdb/testsuite/gdb.python/py-frame-args.py  | 13 +++++++++++++
 5 files changed, 49 insertions(+), 4 deletions(-)

diff --git a/gdb/extension.h b/gdb/extension.h
index a505c68d25e..7067e232cd3 100644
--- a/gdb/extension.h
+++ b/gdb/extension.h
@@ -103,6 +103,10 @@ enum frame_filter_flag
 
     /* Set this flag if elided frames should not be printed.  */
     PRINT_HIDE = 1 << 5,
+
+    /* Set this flag if pretty printers for frame arguments should not
+       be invoked.  */
+    PRINT_RAW_FRAME_ARGUMENTS = 1 << 6,
   };
 
 DEF_ENUM_FLAGS_TYPE (enum frame_filter_flag, frame_filter_flags);
diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c
index 6dd741ab704..e53e3409235 100644
--- a/gdb/python/py-framefilter.c
+++ b/gdb/python/py-framefilter.c
@@ -422,12 +422,14 @@ static enum ext_lang_bt_status
 enumerate_args (PyObject *iter,
 		struct ui_out *out,
 		enum ext_lang_frame_args args_type,
+		bool raw_frame_args,
 		int print_args_field,
 		struct frame_info *frame)
 {
   struct value_print_options opts;
 
   get_user_print_options (&opts);
+  opts.raw = raw_frame_args;
 
   if (args_type == CLI_SCALAR_VALUES)
     {
@@ -655,8 +657,8 @@ py_mi_print_variables (PyObject *filter, struct ui_out *out,
   ui_out_emit_list list_emitter (out, "variables");
 
   if (args_iter != Py_None
-      && (enumerate_args (args_iter.get (), out, args_type, 1, frame)
-	  == EXT_LANG_BT_ERROR))
+      && (enumerate_args (args_iter.get (), out, args_type, opts->raw, 1,
+			  frame) == EXT_LANG_BT_ERROR))
     return EXT_LANG_BT_ERROR;
 
   if (locals_iter != Py_None
@@ -701,6 +703,7 @@ static enum ext_lang_bt_status
 py_print_args (PyObject *filter,
 	       struct ui_out *out,
 	       enum ext_lang_frame_args args_type,
+	       bool raw_frame_args,
 	       struct frame_info *frame)
 {
   gdbpy_ref<> args_iter (get_py_iter_from_func (filter, "frame_args"));
@@ -726,7 +729,8 @@ py_print_args (PyObject *filter,
 	}
     }
   else if (args_iter != Py_None
-	   && (enumerate_args (args_iter.get (), out, args_type, 0, frame)
+	   && (enumerate_args (args_iter.get (), out, args_type,
+			       raw_frame_args, 0, frame)
 	       == EXT_LANG_BT_ERROR))
     return EXT_LANG_BT_ERROR;
 
@@ -957,7 +961,9 @@ py_print_frame (PyObject *filter, frame_filter_flags flags,
      wrong.  */
   if (print_args && (location_print || out->is_mi_like_p ()))
     {
-      if (py_print_args (filter, out, args_type, frame) == EXT_LANG_BT_ERROR)
+      bool raw_frame_args = (flags & PRINT_RAW_FRAME_ARGUMENTS) != 0;
+      if (py_print_args (filter, out, args_type, raw_frame_args, frame)
+	  == EXT_LANG_BT_ERROR)
 	return EXT_LANG_BT_ERROR;
     }
 
diff --git a/gdb/stack.c b/gdb/stack.c
index bce6a2f42f8..dbca5ade1c2 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -2028,6 +2028,8 @@ backtrace_command_1 (const frame_print_options &fp_opts,
     flags |= PRINT_LOCALS;
   if (bt_opts.hide)
     flags |= PRINT_HIDE;
+  if (fp_opts.print_raw_frame_arguments)
+    flags |= PRINT_RAW_FRAME_ARGUMENTS;
 
   if (!bt_opts.no_filters)
     {
diff --git a/gdb/testsuite/gdb.python/py-frame-args.exp b/gdb/testsuite/gdb.python/py-frame-args.exp
index 5d35323c0e6..dae0c0ac29e 100644
--- a/gdb/testsuite/gdb.python/py-frame-args.exp
+++ b/gdb/testsuite/gdb.python/py-frame-args.exp
@@ -34,6 +34,26 @@ gdb_test_no_output "source ${remote_python_file}" "load python file"
 gdb_breakpoint [gdb_get_line_number "break-here"]
 gdb_continue_to_breakpoint "break-here" ".* break-here .*"
 
+# Test raw-frame-arguments on backtrace with and without frame-filter
+foreach_with_prefix filtered {enable disable} {
+    gdb_test_no_output "$filtered frame-filter global BasicFrameFilter"
+
+    gdb_test "bt 1" \
+	".*foo \\(x=42, ss=super struct = {\[.\]{3}}\\).*" \
+	"bt pretty"
+
+    gdb_test "bt -raw-frame-arguments on 1" \
+	".*foo \\(x=42, ss=\[.\]{3}\\).*" \
+	"bt raw"
+
+    # "set print raw-values" should not affect frame arguments
+    gdb_test_no_output "set print raw-values on"
+    gdb_test "bt 1" \
+	".*foo \\(x=42, ss=super struct = {\[.\]{3}}\\).*" \
+	"bt pretty,raw-values"
+    gdb_test_no_output "set print raw-values off"
+}
+
 # Test all combinations with raw off.
 
 gdb_test_no_output "set print raw-frame-arguments off"
diff --git a/gdb/testsuite/gdb.python/py-frame-args.py b/gdb/testsuite/gdb.python/py-frame-args.py
index d80d761b995..3b65eed0dad 100644
--- a/gdb/testsuite/gdb.python/py-frame-args.py
+++ b/gdb/testsuite/gdb.python/py-frame-args.py
@@ -73,3 +73,16 @@ pretty_printers_dict = {}
 
 register_pretty_printers ()
 gdb.pretty_printers.append (lookup_function)
+
+
+class BasicFrameFilter (object):
+    def __init__ (self):
+        self.name = "BasicFrameFilter"
+        self.priority = 100
+        self.enabled = True
+        gdb.frame_filters[self.name] = self
+
+    def filter (self, frame_iter):
+        return frame_iter
+
+BasicFrameFilter ()
-- 
2.30.0