diff options
Diffstat (limited to 'gdb/doc/gdb.texinfo')
| -rw-r--r-- | gdb/doc/gdb.texinfo | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 7f8c785..8e42913 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -18721,9 +18721,25 @@ implement in hardware simple hardware watchpoint conditions of the form: if @var{ADDRESS|VARIABLE} == @var{CONSTANT EXPRESSION} @end smallexample -The DVC register will be automatically used whenever @value{GDBN} detects -such pattern in a condition expression. This feature is available in native -@value{GDBN} running on a Linux kernel version 2.6.34 or newer. +The DVC register will be automatically used when @value{GDBN} detects +such pattern in a condition expression, and the created watchpoint uses one +debug register (either the @code{exact-watchpoints} option is on and the +variable is scalar, or the variable has a length of one byte). This feature +is available in native @value{GDBN} running on a Linux kernel version 2.6.34 +or newer. + +When running on PowerPC embedded processors, @value{GDBN} automatically uses +ranged hardware watchpoints, unless the @code{exact-watchpoints} option is on, +in which case watchpoints using only one debug register are created when +watching variables of scalar types. + +You can create an artificial array to watch an arbitrary memory +region using one of the following commands (@pxref{Expressions}): + +@smallexample +(@value{GDBP}) watch *((char *) @var{address})@@@var{length} +(@value{GDBP}) watch @{char[@var{length}]@} @var{address} +@end smallexample @value{GDBN} provides the following PowerPC-specific commands: @@ -18744,6 +18760,12 @@ arguments and return values. The valid options are @samp{auto}; registers. By default, @value{GDBN} selects the calling convention based on the selected architecture and the provided executable file. +@item set powerpc exact-watchpoints +@itemx show powerpc exact-watchpoints +Allow @value{GDBN} to use only one debug register when watching a variable +of scalar type, thus assuming that the variable is accessed through the +address of its first byte. + @kindex target dink32 @item target dink32 @var{dev} DINK32 ROM monitor. |