libdwfl: Add new function dwfl_frame_regusers/dichen/try-dwfl-frame-reg

Dwfl has most of the infrastructure to keep the full unwind state,
including the state of unwound registers per frame using
Dwfl_Thread_Callbacks. But there is no public API to access the state,
except for the PC (dwfl_frame_pc).

This commit adds a new function dwfl_frame_reg to get the value of the
DWARF register number in the given frame.

https://sourceware.org/bugzilla/show_bug.cgi?id=28579

Signed-off-by: Di Chen <dichen@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/libdw/libdw.map b/libdw/libdw.map
index 6da25561..8f393438 100644
--- a/libdw/libdw.map
+++ b/libdw/libdw.map
@@ -370,4 +370,5 @@ ELFUTILS_0.186 {
 ELFUTILS_0.188 {
   global:
     dwfl_get_debuginfod_client;
+    dwfl_frame_reg;
 } ELFUTILS_0.186;