Re-apply r175688, with the changes suggested by Jakob in PR15320.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175809 91177308-0d34-0410-b5e6-96231b3b80d8
Allow GlobalValues to vectorize with AliasAnalysis

Storing the load/store instructions with the values
and inspect them using Alias Analysis to make sure
they don't alias, since the GEP pointer operand doesn't
take the offset into account.

Trying hard to not add any extra cost to loads and stores
that don't overlap on global values, AA is *only* calculated
if all of the previous attempts failed.

Using biggest vector register size as the stride for the
vectorization access, as we're being conservative and
the cost model (which calculates the real vectorization
factor) is only run after the legalization phase.

We might re-think this relationship in the future, but
for now, I'd rather be safe than sorry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175818 91177308-0d34-0410-b5e6-96231b3b80d8
Limit cast machinery to preserve const and not accept temporaries

After cleaning up the following type hierarchies:
  * TypeLoc: r175462
  * SVal: r175594
  * CFGElement: r175462
  * ProgramPoint: r175812
that all invoked undefined behavior by causing a derived copy construction of a
base object through an invalid cast (thus supporting code that relied on
casting temporaries that were direct base objects) Clang/LLVM is now clean of
casts of temporaries. So here's some fun SFINAE machinery (courtesy of Eli
Friedman, with some porting back from C++11 to LLVM's traits by me) to cause
compile-time failures if llvm::cast & friends are ever passed an rvalue.

This should avoid a repeat of anything even remotely like PR14321/r168124.

Thanks to Jordan Rose for the help with the various Static Analyzer related
hierarchies that needed cleaning up, Eli for the SFINAE, Richard Smith, John
McCall, Ted Kremenek, and Anna Zaks for their input/reviews/patience along the
way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175819 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, parsing capability of the .debug_frame section was added
to lib/DebugInfo, with dumping in llvm-dwarfdump. This patch adds
initial ability to parse and dump CFA instructions contained in
entries.

To keep it manageable, the patch omits some more advanced capabilities
(accounted in TODOs):

* Parsing of instructions with BLOCK arguments (expression lists)
* Dumping of actual instruction arguments (currently only names are
dumped). This is quite tricky since the dumper has to effectively
"interpret" the instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175820 91177308-0d34-0410-b5e6-96231b3b80d8
Stop relying on physical register kill flags in isKilled() in the two-address
pass. One of the callers of isKilled() can cope with overapproximation of kills
and the other can't, so I added a flag to indicate this.

In theory this could pessimize code slightly, but in practice most physical
register uses are kills, and most important kills of physical registers are the
only uses of that register prior to register allocation, so we can recognize
them as kills even without kill flags.

This is relevant because LiveIntervals gets rid of all kill flags.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175821 91177308-0d34-0410-b5e6-96231b3b80d8