Add new debug kind LocTrackingOnly.

Summary:
This new debug emission kind supports emitting line location
information in all instructions, but stops code generation
from emitting debug info to the final output.

This mode is useful when the backend wants to track source
locations during code generation, but it does not want to
produce debug info. This is currently used by optimization
remarks (-pass-remarks, -pass-remarks-missed and
-pass-remarks-analysis).

To prevent debug info emission, DIBuilder never inserts the
annotation 'llvm.dbg.cu' when LocTrackingOnly is enabled.

Reviewers: echristo, dblaikie

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D4234
Add new debug kind LocTrackingOnly.

Summary:
This new debug emission kind supports emitting line location
information in all instructions, but stops code generation
from emitting debug info to the final output.

This mode is useful when the backend wants to track source
locations during code generation, but it does not want to
produce debug info. This is currently used by optimization
remarks (-Rpass, -Rpass-missed and -Rpass-analysis).

When one of the -Rpass flags is used, the front end will enable
location tracking, only if no other debug option is enabled.

To prevent debug information from being generated, a new debug
info kind LocTrackingOnly causes DIBuilder::createCompileUnit() to
not emit the llvm.dbg.cu annotation. This blocks final code generation
from generating debug info in the back end.

Depends on D4234.

Reviewers: echristo, dblaikie

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D4235
Objective-C. When we use @selector(save:), etc. there may be more
than one method with mismatched type of same selector name.
clang issues a warning to point this out since it may cause
undefined behavior. There are cases though that some APIs
don't care about user methods and such warnings are perceived as
noise. This patch allows users to add paren delimiters around
selector name to turn off such warnings. So, @selector((save:)) will
turn off the warning. It also provides 'fixit' so user knows
what to do. // rdar://16458579
[Refactor] Create nicer test cases from C/C++

Insert a header into the new testcase containing a sample RUN line a FIXME and
an XFAIL. Then insert the formated C code and finally the LLVM-IR without
attributes, the module ID or the target triple.