Mesa (master): gallium/util: tweak backtrace format with libunwind

[Rob Clark]

Module: Mesa
Branch: master
Commit: 3b32ec3ba65deefedfe74e594872e675d34a310a
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=3b32ec3ba65deefedfe74e594872e675d34a310a

Author: Rob Clark <robdclark at gmail.com>
Date:   Tue Apr  4 13:01:56 2017 -0400

gallium/util: tweak backtrace format with libunwind

To work with addr2line.sh we also need the relative offset within the
DSO.  And addr2line.sh gets confused by the leading stackframe number.

Signed-off-by: Rob Clark <robdclark at gmail.com>

---

 src/gallium/auxiliary/util/u_debug_stack.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/src/gallium/auxiliary/util/u_debug_stack.c b/src/gallium/auxiliary/util/u_debug_stack.c
index a5829316e4..7013807b6b 100644
--- a/src/gallium/auxiliary/util/u_debug_stack.c
+++ b/src/gallium/auxiliary/util/u_debug_stack.c
@@ -143,15 +143,19 @@ frame_ip(const struct debug_stack_frame *frame)
 }
 
 static const char *
-frame_filename(const struct debug_stack_frame *frame)
+frame_info(const struct debug_stack_frame *frame, unsigned *offset)
 {
    Dl_info dlinfo;
+   const void *addr = frame_ip(frame);
 
 
-   if (dladdr(frame_ip(frame), &dlinfo) && dlinfo.dli_fname &&
-           *dlinfo.dli_fname)
-       return dlinfo.dli_fname;
+   if (dladdr(addr, &dlinfo) && dlinfo.dli_fname &&
+           *dlinfo.dli_fname) {
+      *offset = (unsigned)((uintptr_t)addr - (uintptr_t)dlinfo.dli_fbase);
+      return dlinfo.dli_fname;
+   }
 
+   *offset = 0;
    return "?";
 }
 
@@ -159,13 +163,14 @@ void
 debug_backtrace_dump(const struct debug_stack_frame *backtrace,
                      unsigned nr_frames)
 {
-   unsigned i;
+   unsigned i, offset;
+   const char *filename;
 
    for (i = 0; i < nr_frames; ++i) {
       if (!backtrace[i].start_ip)
          break;
-      debug_printf("\t%u: %s (%s+0x%x) [%p]\n", i,
-            frame_filename(&backtrace[i]),
+      filename = frame_info(&backtrace[i], &offset);
+      debug_printf("\t%s(+0x%x) (%s+0x%x) [%p]\n", filename, offset,
             backtrace[i].procname, backtrace[i].off,
             frame_ip(&backtrace[i]));
    }
@@ -176,13 +181,14 @@ debug_backtrace_print(FILE *f,
                       const struct debug_stack_frame *backtrace,
                       unsigned nr_frames)
 {
-   unsigned i;
+   unsigned i, offset;
+   const char *filename;
 
    for (i = 0; i < nr_frames; ++i) {
       if (!backtrace[i].start_ip)
          break;
-      fprintf(f, "\t%u: %s (%s+0x%x) [%p]\n", i,
-            frame_filename(&backtrace[i]),
+      filename = frame_info(&backtrace[i], &offset);
+      fprintf(f, "\t%s(+0x%x) (%s+0x%x) [%p]\n", filename, offset,
             backtrace[i].procname, backtrace[i].off,
             frame_ip(&backtrace[i]));
    }