LoopUnrollRuntime: Check for overflow in the trip count calculation.

Fixes PR19823.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211436 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, introduced total ordering among top-level comparison
methods.
    
Patch changes return type of FunctionComparator::compare() and
FunctionComparator::compare(const BasicBlock*, const BasicBlock*)
methods from bool (equal or not) to {-1, 0, 1} (less, equal, great).
    
This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211437 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, introduced sanity check, that checks order relation,
introduced among functions set.
    
This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211442 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions, doSanityCheck: fixed body comments.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211443 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, removed unused methods from old implementation.
    
Patch removed next old FunctionComparator methods:
    * enumerate
    * isEquivalentOperation
    * isEquivalentGEP
    * isEquivalentType 
    
This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211444 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, FnSet has been replaced with FnTree.

Patch activates new implementation.
So from now, merging process should take time O(N*log(N)).
Where N size of module (we are free to measure it in
functions or in instructions). Internally FnTree represents
binary tree. So every lookup operation takes O(log(N)) time.

It is still not the last patch in series, we also have to
clean-up pass from old code, and update pass comments.

This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211445 91177308-0d34-0410-b5e6-96231b3b80d8
Report error for non-zero data in .bss

User may initialize a var with non-zero value and specify .bss section.
E.g. : int a __attribute__((section(".bss"))) = 2;

This patch converts an assertion to error report for better user
experience.

Differential Revision: http://reviews.llvm.org/D4199


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211455 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, updated header comments.

Added short description for new comparison algorithm, that introduces
total ordering among functions set.

This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211456 91177308-0d34-0410-b5e6-96231b3b80d8
MergeFunctions Pass, removed DenseMap helpers.

Patch removes rest part of code related to old implementation.

This patch belongs to patch series that improves MergeFunctions
performance time from O(N*N) to O(N*log(N)).

This one was the final patch.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211457 91177308-0d34-0410-b5e6-96231b3b80d8
LoopVectorizer: Fix a dominance issue

The induction variables start value needs to be defined before we branch
(overflow check) to the scalar preheader where we used it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211460 91177308-0d34-0410-b5e6-96231b3b80d8
Add a description to the test from r211433 explaining why it's written that way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211465 91177308-0d34-0410-b5e6-96231b3b80d8
Introduce a Lit feature "debug_frame" and apply it to llvm/test/MC/ELF/cfi-version.ll.

.debug_frame is not emitted for targeting Windows x64.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211466 91177308-0d34-0410-b5e6-96231b3b80d8
Fix PR20087 by using the source index when changing the vector load

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211472 91177308-0d34-0410-b5e6-96231b3b80d8