Issue in StackwalkerAMD64::GetCallerByFramePointerRecovery.

Issue in StackwalkerAMD64::GetCallerByFramePointerRecovery.

There is an issue in StackwalkerAMD64::GetCallerByFramePointerRecovery.
Occasionally it produces invalid frames (instruction pointer == 0) which
prevents the AMD64 stack walker from proceeding to do stack scanning and
instead leads to premature termination of the stack walking process.

For more details: http://crbug/537444

BUG=
R=mark@chromium.org

Committed: https://chromium.googlesource.com/breakpad/breakpad/+/4da1cfbad248e846b6e0b4429b4eb639bb2d1970

[ivanpe, 2015-10-16 01:45:17]

ivanpe@chromium.org changed reviewers:
+ mark@chromium.org, rsesek@chromium.org, ted.mielczarek@gmail.com

[Mark Mentovai, 2015-10-16 02:44:18]

https://codereview.chromium.org/1408973002/diff/1/src/processor/stackwalker_a...
File src/processor/stackwalker_amd64.cc (right):

https://codereview.chromium.org/1408973002/diff/1/src/processor/stackwalker_a...
src/processor/stackwalker_amd64.cc:195: if (caller_rbp < last_rbp || caller_rsp
< last_rsp)
This caller_rsp < last_rsp check is duplicated in IsEndOfStack().

Perhaps you should remove it from here and combine these into

  if (IsEndOfStack(caller_rip, caller_rsp, last_rsp) || caller_rbp < last_rbp) {

[ivanpe, 2015-10-16 03:35:42]

https://codereview.chromium.org/1408973002/diff/1/src/processor/stackwalker_a...
File src/processor/stackwalker_amd64.cc (right):

https://codereview.chromium.org/1408973002/diff/1/src/processor/stackwalker_a...
src/processor/stackwalker_amd64.cc:195: if (caller_rbp < last_rbp || caller_rsp
< last_rsp)
On 2015/10/16 02:44:18, Mark Mentovai wrote:
> This caller_rsp < last_rsp check is duplicated in IsEndOfStack().
> 
> Perhaps you should remove it from here and combine these into
> 
>   if (IsEndOfStack(caller_rip, caller_rsp, last_rsp) || caller_rbp < last_rbp)
{

Done.

[Mark Mentovai, 2015-10-16 03:38:40]

LGTM

[ivanpe, 2015-10-16 03:47:21]

Committed patchset #2 (id:20001) manually as
4da1cfbad248e846b6e0b4429b4eb639bb2d1970 (presubmit successful).