- Remove the printf0 special handling as we treat it as printf anyway.
- Perform basic checks (non-literal, empty) for all formats and not only printf/scanf.
llvm-svn: 149236
frames might go away (the object itself, not the actual logical frame) when
we are single stepping due to the way we currently sometimes end up flushing
frames when stepping in/out/over. They later will come back to life
represented by another object yet they have the same StackID. Now when you get
a lldb::SBFrame object, it will track the frame it is initialized with until
the thread goes away or the StackID no longer exists in the stack for the
thread it was created on. It uses a weak_ptr to both the frame and thread and
also stores the StackID. These three items allow us to determine when the
stack frame object has gone away (the weak_ptr will be NULL) and allows us to
find the correct frame again. In our test suite we had such cases where we
were just getting lucky when something like this happened:
1 - stop at breakpoint
2 - get first frame in thread where we stopped
3 - run an expression that causes the program to JIT and run code
4 - run more expressions on the frame from step 2 which was very very luckily
still around inside a shared pointer, yet, not part of the current
thread (a new stack frame object had appeared with the same stack ID and
depth).
We now avoid all such issues and properly keep up to date, or we start
returning errors when the frame doesn't exist and always responds with
invalid answers.
Also fixed the UserSettingsController (not going to rewrite this just yet)
so that it doesn't crash on shutdown. Using weak_ptr's came in real handy to
track when the master controller has already gone away and this allowed me to
pull out the previous NotifyOwnerIsShuttingDown() patch as it is no longer
needed.
llvm-svn: 149231
each of the targets. Use this for module requirements, so that we can
pin the availability of certain modules to certain target features,
e.g., provide a module for xmmintrin.h only when SSE support is
available.
Use these feature names to provide a nearly-complete module map for
Clang's built-in headers. Only mm_alloc.h and unwind.h are missing,
and those two are fairly specialized at the moment. Finishes
<rdar://problem/10710060>.
llvm-svn: 149227
all RTTI types, and since we don't use RTTI anymore since clang and llvm don't
we don't really need this header file. All shared pointer definitions have
been moved into "lldb-forward.h".
Defined std::tr1::weak_ptr definitions for all of the types that inherit from
enable_shared_from_this() in "lldb-forward.h" in preparation for thread
hardening our public API.
The first in the thread hardening check-ins. First we start with SBThread.
We have issues in our lldb::SB API right now where if you have one object
that is being used by two threads we have a race condition. Consider the
following code:
1 int
2 SBThread::SomeFunction()
3 {
4 int result = -1;
5 if (m_opaque_sp)
6 {
7 result = m_opaque_sp->DoSomething();
8 }
9 return result;
10 }
And now this happens:
Thread 1 enters any SBThread function and checks its m_opaque_sp and is about
to execute the code on line 7 but hasn't yet
Thread 2 gets to run and class sb_thread.Clear() which calls m_opaque_sp.clear()
and clears the contents of the shared pointer member
Thread 1 now crashes when it resumes.
The solution is to use std::tr1::weak_ptr. Now the SBThread class contains a
lldb::ThreadWP (weak pointer to our lldb_private::Thread class) and this
function would look like:
1 int
2 SBThread::SomeFunction()
3 {
4 int result = -1;
5 ThreadSP thread_sp(m_opaque_wp.lock());
6 if (thread_sp)
7 {
8 result = m_opaque_sp->DoSomething();
9 }
10 return result;
11 }
Now we have a solid thread safe API where we get a local copy of our thread
shared pointer from our weak_ptr and then we are guaranteed it can't go away
during our function.
So lldb::SBThread has been thread hardened, more checkins to follow shortly.
llvm-svn: 149218
due to RTTI worries since llvm and clang don't use RTTI, but I was able to
switch back with no issues as far as I can tell. Once the RTTI issue wasn't
an issue, we were looking for a way to properly track weak pointers to objects
to solve some of the threading issues we have been running into which naturally
led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared
pointer from just a pointer, which is also easily solved using the
std::tr1::enable_shared_from_this class.
The main reason for this move back is so we can start properly having weak
references to objects. Currently a lldb_private::Thread class has a refrence
to its parent lldb_private::Process. This doesn't work well when we now hand
out a SBThread object that contains a shared pointer to a lldb_private::Thread
as this SBThread can be held onto by external clients and if they end up
using one of these objects we can easily crash.
So the next task is to start adopting std::tr1::weak_ptr where ever it makes
sense which we can do with lldb_private::Debugger, lldb_private::Target,
lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and
many more objects now that they are no longer using intrusive ref counted
pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive
pointers).
llvm-svn: 149207
headers. The remaining headers require more sophisticated
requirements; they'll be handled separately. Part of
<rdar://problem/10710060>.
llvm-svn: 149206
for getting the name of the module file, unifying the code for
searching for a module with a given name (into lookupModule()) and
separating out the mapping to a module file (into
getModuleFileName()). No functionality change.
llvm-svn: 149197
- Don't call malloc+free in the very hot forward().
- Don't call isTiedToDefOperand().
- Don't create BitVector temporaries.
- Merge DeadRegs into KillRegs.
- Eliminate the early clobber checks, they were irrelevant to scavenging.
- Remove unnecessary code from -Asserts builds.
This speeds up ARM PEI by 3.4x and overall llc -O0 codegen time by 11%.
llvm-svn: 149189
Craig Topper