[doc] Mention accelerated watchpoint conditions in the gdb manual

[doc] Mention accelerated watchpoint conditions in the gdb manual

[Thiago Jung Bauermann]

Hi,

I mentioned this feature in the NEWS file but I just realized that it
would be useful to mention in the manual too. Ok to apply? For the
branch too?
-- 
[]'s
Thiago Jung Bauermann
IBM Linux Technology Center


2010-08-17  Thiago Jung Bauermann  <bauerman@br.ibm.com>

	* gdb.texinfo (PowerPC Embedded): Mention support for the DVC register.

Index: gdb.git/gdb/doc/gdb.texinfo
===================================================================
--- gdb.git.orig/gdb/doc/gdb.texinfo	2010-08-17 12:22:56.000000000 -0300
+++ gdb.git/gdb/doc/gdb.texinfo	2010-08-17 12:30:34.000000000 -0300
@@ -18472,6 +18472,17 @@ Set suspend trace mode.
 @node PowerPC Embedded
 @subsection PowerPC Embedded
 
+@value{GDBN} supports using the DVC (Data Value Compare) register to
+implement in hardware simple hardware watchpoint conditions of the form:
+
+@smallexample
+(@value{GDBP}) watch @var{ADDRESS|VARIABLE} 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.
+
 @value{GDBN} provides the following PowerPC-specific commands:
 
 @table @code

Re: [doc] Mention accelerated watchpoint conditions in the gdb manual

[Eli Zaretskii]

> From: Thiago Jung Bauermann <bauerman@br.ibm.com>
> Date: Tue, 17 Aug 2010 16:40:39 -0300
> 
> I mentioned this feature in the NEWS file but I just realized that it
> would be useful to mention in the manual too. Ok to apply? For the
> branch too?

Yes and yes.  Thanks.

> +@smallexample
> +(@value{GDBP}) watch @var{ADDRESS|VARIABLE} if  @var{ADDRESS|VARIABLE} == @var{CONSTANT EXPRESSION}
> +@end smallexample

Please break the long line in two: it's too long and will overflow the
page boundary in the printed manual.

Also, please add a "@cindex DVC register" entry here.

Re: [doc] Mention accelerated watchpoint conditions in the gdb manual

[Thiago Jung Bauermann]

On Tue, 2010-08-17 at 22:55 +0300, Eli Zaretskii wrote:
> > From: Thiago Jung Bauermann <bauerman@br.ibm.com>
> > Date: Tue, 17 Aug 2010 16:40:39 -0300
> > 
> > I mentioned this feature in the NEWS file but I just realized that it
> > would be useful to mention in the manual too. Ok to apply? For the
> > branch too?
> 
> Yes and yes.  Thanks.

Thanks!

> > +@smallexample
> > +(@value{GDBP}) watch @var{ADDRESS|VARIABLE} if  @var{ADDRESS|VARIABLE} == @var{CONSTANT EXPRESSION}
> > +@end smallexample
> 
> Please break the long line in two: it's too long and will overflow the
> page boundary in the printed manual.

I had tested this on gdb.pdf and the generated line is shorter than the
surrounding paragraphs. Though I just checked gdb.info and the line ends
at column 77, which is larger than the surrounding paragraphs...

> Also, please add a "@cindex DVC register" entry here.

Done.

What about this version? The broken line shows up nicely in both gdb.pdf
and gdb.info.
-- 
[]'s
Thiago Jung Bauermann
IBM Linux Technology Center


2010-08-17  Thiago Jung Bauermann  <bauerman@br.ibm.com>

	* gdb.texinfo (PowerPC Embedded): Mention support for the DVC register.

Index: gdb.git/gdb/doc/gdb.texinfo
===================================================================
--- gdb.git.orig/gdb/doc/gdb.texinfo	2010-08-17 17:05:08.000000000 -0300
+++ gdb.git/gdb/doc/gdb.texinfo	2010-08-17 17:09:50.000000000 -0300
@@ -18472,6 +18472,19 @@ Set suspend trace mode.
 @node PowerPC Embedded
 @subsection PowerPC Embedded
 
+@cindex DVC register
+@value{GDBN} supports using the DVC (Data Value Compare) register to
+implement in hardware simple hardware watchpoint conditions of the form:
+
+@smallexample
+(@value{GDBP}) watch @var{ADDRESS|VARIABLE} \
+  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.
+
 @value{GDBN} provides the following PowerPC-specific commands:
 
 @table @code

Re: [doc] Mention accelerated watchpoint conditions in the gdb manual

[Eli Zaretskii]

> From: Thiago Jung Bauermann <bauerman@br.ibm.com>
> Cc: gdb-patches@sourceware.org
> Date: Tue, 17 Aug 2010 17:19:43 -0300
> 
> > > +@smallexample
> > > +(@value{GDBP}) watch @var{ADDRESS|VARIABLE} if  @var{ADDRESS|VARIABLE} == @var{CONSTANT EXPRESSION}
> > > +@end smallexample
> > 
> > Please break the long line in two: it's too long and will overflow the
> > page boundary in the printed manual.
> 
> I had tested this on gdb.pdf and the generated line is shorter than the
> surrounding paragraphs.

It depends on the fonts used by TeX.  In general, any line in
@smallexample that is longer than 72 characters is unsafe.

> What about this version?

It's fine, thanks.

Re: [doc] Mention accelerated watchpoint conditions in the gdb manual

[Thiago Jung Bauermann]

On Tue, 2010-08-17 at 23:32 +0300, Eli Zaretskii wrote:
> > From: Thiago Jung Bauermann <bauerman@br.ibm.com>
> > Cc: gdb-patches@sourceware.org
> > Date: Tue, 17 Aug 2010 17:19:43 -0300
> > What about this version?
> 
> It's fine, thanks.

Thanks, committed to both HEAD and the branch.
-- 
[]'s
Thiago Jung Bauermann
IBM Linux Technology Center