[OPENMP] Codegen for 'firstprivate' clause.
This patch generates some helper variables that used as private copies of the corresponding original variables inside an OpenMP 'parallel' directive. These generated variables are initialized by copy using values of the original variables (with the copy constructor, if any). For arrays, initializator is generated for single element and in the codegen procedure this initial value is automatically propagated between all elements of the private copy.
In outlined function, references to original variables are replaced by the references to these private helper variables. At the end of the initialization of the private variables an implicit barier is generated by calling __kmpc_barrier(...) runtime function to be sure that all threads were initialized using original values of the variables.
Differential Revision: http://reviews.llvm.org/D5140


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219306 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "Remove threshold on object size for inserting lifetime begin / end"

Revert this patch while I investigate some sanitizer failures off-line.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219307 91177308-0d34-0410-b5e6-96231b3b80d8
Fix test OpenMP/parallel_firstprivate_codegen.cpp
Fixed compatibility issues with MSVC mode and ARM target.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@219309 91177308-0d34-0410-b5e6-96231b3b80d8