diff mbox

Tweak gdb.trace/tfile.c for thumb mode

Message ID 53BDEBD8.5030201@codesourcery.com
State Committed
Headers

Commit Message

Yao Qi July 10, 2014, 1:26 a.m. UTC 
  On 07/09/2014 10:52 PM, Pedro Alves wrote:
> #if defined(__thumb__) || defined(__thumb2__)
>   /* Although Thumb functions are two-byte aligned, function
>      pointers have the Thumb bit set.  Clear it.  */
>   func_addr &= ~1;
> #endif
> 
> (This bit is widely known as the "Thumb bit", so call it that,
> and remove a few "the"'s that sound odd to me, and say
> "two-byte aligned".)

I often associate "Thumb bit" with the bit in CPSR.  Look into
arm-tdep.c and arm-linux-tdep.c, "Thumb bit" is used for both cases
(LSB of function address and the bit in CPSR).  It shouldn't cause any
confusion.

Patch is updated as you suggested and pushed in.
diff mbox

Patch

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 19e6232..2278496 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@ 
+2014-07-10  Yao Qi  <yao@codesourcery.com>
+
+	* gdb.trace/tfile.c (write_basic_trace_file)
+	[__thumb__||__thumb2__]: Clear the Thumb bit of the function
+	address written to trace file.
+
 2014-07-09  Pedro Alves  <palves@redhat.com>
 
 	* gdb.base/attach-wait-input.exp: New file.
diff --git a/gdb/testsuite/gdb.trace/tfile.c b/gdb/testsuite/gdb.trace/tfile.c
index ac65901..bc25b80 100644
--- a/gdb/testsuite/gdb.trace/tfile.c
+++ b/gdb/testsuite/gdb.trace/tfile.c
@@ -91,6 +91,7 @@  write_basic_trace_file (void)
 {
   int fd, int_x;
   short short_x;
+  long func_addr;
 
   fd = start_trace_file (TFILE_DIR "tfile-basic.tf");
 
@@ -109,8 +110,14 @@  write_basic_trace_file (void)
   /* Dump tracepoint definitions, in syntax similar to that used
      for reconnection uploads.  */
   /* FIXME need a portable way to print function address in hex */
-  snprintf (spbuf, sizeof spbuf, "tp T1:%lx:E:0:0\n",
-	    (long) &write_basic_trace_file);
+  func_addr = (long) &write_basic_trace_file;
+#if defined(__thumb__) || defined(__thumb2__)
+  /* Although Thumb functions are two-byte aligned, function
+     pointers have the Thumb bit set.  Clear it.  */
+  func_addr &= ~1;
+#endif
+
+  snprintf (spbuf, sizeof spbuf, "tp T1:%lx:E:0:0\n", func_addr);
   write (fd, spbuf, strlen (spbuf));
   /* (Note that we would only need actions defined if we wanted to
      test tdump.) */