Re: [PATCH 5/5] range stepping: tests

Pedro Alves
2013-05-23T18:03:29Z

On 05/22/2013 03:02 PM, Yao Qi wrote:> On 05/21/2013 02:28 AM, Pedro Alves wrote:
>> I see. Thanks, that's much more detailed info than just saying "it's unsafe".
>>
>> I'm guessing the huge number of RSP packets comes from that big loop in the
>> test:
>>
>> /* Generate a range that includes a loop, which is time consuming.
>> Variable C is used to terminate the loop earlier when GDB
>> wants. */
>> for (c = 1, a = 0; a < 65535 && c; a++) {for (b = 0; b < 65535 && c; b++) { d1 = d2 * a / b; d2 = d1 *
>>
>> We could skip most of the range stepping tests if e.g., the
>> test that steps the short line FAILs:
>>
>> /* A line of source will be generated to a number of
>> instructions by compiler. */
>> a = b + c + d * e - a; /* location 1 */
>>
>> WDYT?
>
> Pedro,
> That is a good idea. It works for my internal stub! I'll post a delta patch on top of yours.

...

> The patch below is to skip the rest of range stepping tests if the
> first one fails, to avoid the issue of huge number of rsp packets in
> gdb.log. It is on top of your series. It works well with my stub.

Thanks!

> 2013-05-22 Yao Qi <yao@codesourcery.com>
>
> * gdb.base/range-stepping.exp: Skip the rest of tests if test
> fails.
> ---
> gdb/testsuite/gdb.base/range-stepping.exp | 8 ++++++++
> 1 files changed, 8 insertions(+), 0 deletions(-)
>
> diff --git a/gdb/testsuite/gdb.base/range-stepping.exp b/gdb/testsuite/gdb.base/range-stepping.exp
> index def25ce..aa5d34f 100644
> --- a/gdb/testsuite/gdb.base/range-stepping.exp
> +++ b/gdb/testsuite/gdb.base/range-stepping.exp
> @@ -85,6 +85,14 @@ with_test_prefix "multi insns" {
> set pc_after_stepping $expect_out(1,string)
> pass $msg
> }
> + -re ".*" {

This should not leave the prompt in the buffer, as it may
confuse the next test.

But I'm not understanding how this is catching the issue. Why
would "print/x \$pc" fail if the stub degenerates to
implementing vCont;r as a single instruction step?

> + fail $msg
> + # It is the first test on range-stepping, and the simplest
> + # one. If it fails, probably the rest of the tests fail
> + # and huge number of rsp packets will blow up the gdb.log
> + # file. Skip the rest of the tests.

Suggest minor editing:

# This is the first range-stepping test, and the simplest
# one. If it fails, probably the rest of the tests would
# fail too, and the huge number of rsp packets in the test with
# the time-consuming loop would blow up the gdb.log file.
# Skip the rest of the tests.

> + return
> + }
> }
>
> # There should be at least two instructions between

--
Pedro Alves