This reverts commit 783cddc4.

Remove globbing of header and source files in core.

this helper is in the ROOT::Internal namespace. The hash used is sha256
through the ROOT::Internal::RSha256Hash class.
Even if this is technically a container, it's not in core/cont because of
dependency issues: we do not want core to depend thread and viceversa.

This refactors the CMake build files to no longer manually call
the CMake functions for generating and linking the dicionairies.
One reason is to reduce boilerplate, the other is that it is now
no longer possible to have naming mismatches between the dictionary
generation arguments and linking function arguments which was causing
the race conditions we had in our build system.

This also now follows more strictly the separation between dependencies
like Math, Tree and Core and pure linking flags to external libraries.

ROOT_GENERATE_DICTIONARY allows to specify dependencies, but we currently
don't actually specify those. As we need this for getting the module
dependencies right (as we can't build missing modules on demand), we should
add those dependencies here. Then those dependencies propagate to the
rootcling invocation which will in the future also generate the C++ module
for the selected dictionary.

and allows to manage implicit multithreading.

TScheduler -> TPoolManager. Renames and changes completely its
implementation.

Tested that won't interfere with previous instantiations of tbb, for
example other frameworks with an instance of the tbb scheduler already
running when loading ROOT.

Solves conflicting behaviours between classes depending on tbb.

See more here: https://indico.cern.ch/event/607814/contributions/2466931/attachments/1409778/2155811/TScheduler.pdf

This patch realizes the reorganizational changes outlined in ROOT-8513.
In details:
   - Move TExecutor into core/base
   - The multi-thread Tree processor TTreeProcessor is renamed TTreeProcessorMT
   - The TTree porcessing part of TProcessExecutor is moved to a new
     class TTreeProcessorMP situated under tree/treeplayer (the interface
     is under ROOT) as TTreeProcessorMT. The methods are renamed 'Process' instead
     of ProcTree for symmetry.
   - The internal classes depending on libTree and libRIO (TPoolPlayer, TPoolProcessor)
     are also moved to tree/treeplayer and reorganized in such a way to remove code
     duplication. Their names are also changed to reflect their task.
     The new code is the new files TMPWorkerTree{.h,.cxx}.
   - The internal clas TPoolWorker is renamed TMPWorkerExecutor to reflect its task.

Replaces if(builtin_foo) statements with explicit support in the
various ROOT macros.

This removes ROOT_ADD_BUILTIN_DEPENDENCIES and adds BUILD_BYPRODUCTS
for the external projects.  This way, the build system can explicitly
depend on the output file of the external project instead of introducing
a hidden dependency..

This commit provides an implementation of a new implicit multi-threading
(IMT) use case, incarnated in method TTreeProcessor::Process.

TTProcessor::Process allows to process the entries of a TTree in parallel.
The user provides a function that receives one parameter, a TTreeReader,
that can be used to iterate over a subrange of entries. Each subrange
corresponds to a cluster in the TTree and is processed by a task, which
can potentially be run in parallel with other tasks.

In order to enable this new IMT use case, other changes are introduced:
- Global flag to enable this IMT use case (enabled implicitly inside
TTProcessor::Process).
- Spin lock implementation of a Read-Write lock.
- RW lock protection in TFile, activated only when calling
TTProcessor::Process.

o Properly put in the ROOT directory the TThreadedObject header
o Remove the ThreadIndex header as not necessary anymore
o Refactor and extensively document the TThreadedObject class
  - Better handling of size of slot array
  - Correct handling of pointers
  - Add the Get and GetAtSlotUnchecked methods
  - Move the assigning of slot index from an external helper to the class itself
o Update the tutorial and its documentation

o CMakeLists modify to take into account the new files
o Factorise the finding of the thread index and the TThreadedObject class
  - TBB will be easily pluggable if required
o Tutorial which shows how to fill histograms in parallel from multiple threads
  - "Symmetric" to mp201 where the TMultiProc class is used

Removed option 'tbb'. Enable TBB when using the option 'imt'. Inverted the logic to unable 'builtin_tbb' if TBB is not found in the system.

This commit provides a task-based parallelisation of
TTree::GetEntry. The approach is based on creating a task per
top-level branch in order to do the reading, unzipping and
deserialisation in parallel.

This commit introduces functions to enable, disable and check (at a
global level) the implicit multi-threaded parallelisation in ROOT.

Ensure that rootcling is built from object files (object libraries) instead of shared libraries to avoid core dumps. It should fix issue ROOT-6276.

now the library names in the rootmaps are sane.
In addition, the creation of the tmva and genvector dicts was
simplified.

mechanism which does not involve rlibmap anymore but
rootcling instead.
Basically all the calls to the macro calling rlibmap have been
removed.

Signed-off-by: Danilo Piparo <danilo.piparo@cern.ch>
Signed-off-by: Fons Rademakers <Fons.Rademakers@cern.ch>

thread_local and pthread specific.


git-svn-id: http://root.cern.ch/svn/root/trunk@43153 27541ba8-7e3a-0410-8455-c3a389f83636

Attached is a number of changes to polish the dependencies between libraries
when using CMake to build on top of ROOT.


git-svn-id: http://root.cern.ch/svn/root/trunk@42575 27541ba8-7e3a-0410-8455-c3a389f83636

cleanup some undesired library dependencies.


git-svn-id: http://root.cern.ch/svn/root/trunk@42549 27541ba8-7e3a-0410-8455-c3a389f83636