[Transforms] Change std::sort to llvm::sort in response to r327219

Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: kcc, pcc, danielcdh, jmolloy, sanjoy, dberlin, ruiu

Reviewed By: ruiu

Subscribers: ruiu, llvm-commits

Differential Revision: https://reviews.llvm.org/D45142

llvm-svn: 330059
diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index e3d2c17..bbe17ed 100644
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -1128,11 +1128,12 @@
   // matter as we're just trying to build up the map from inside-out; we use
   // the map in a more stably ordered way below.
   auto OrderedClonedExitsInLoops = ClonedExitsInLoops;
-  std::sort(OrderedClonedExitsInLoops.begin(), OrderedClonedExitsInLoops.end(),
-            [&](BasicBlock *LHS, BasicBlock *RHS) {
-              return ExitLoopMap.lookup(LHS)->getLoopDepth() <
-                     ExitLoopMap.lookup(RHS)->getLoopDepth();
-            });
+  llvm::sort(OrderedClonedExitsInLoops.begin(),
+             OrderedClonedExitsInLoops.end(),
+             [&](BasicBlock *LHS, BasicBlock *RHS) {
+               return ExitLoopMap.lookup(LHS)->getLoopDepth() <
+                      ExitLoopMap.lookup(RHS)->getLoopDepth();
+             });
 
   // Populate the existing ExitLoopMap with everything reachable from each
   // exit, starting from the inner most exit.