[OpenMP]Update to clang 3.8 ReleaseNotes.rst

[• fraggamuffin]

Summary

This updates the clang 3.8 release notes with OpenMP support statement.

[• fraggamuffin]

Fix spelling in dependencies

[ABataev]

Michael, we have some updates also:

Several new features are supported by Clang:

- Array sections [2.4, Array Sections].

- Directive name modifiers for ``if`` clause [2.12, if Clause].

- ``linear`` clause can be used in loop-based directives [2.7.2, loop Construct].

- ``simdlen`` clause [2.8, SIMD Construct].

- ``hint`` clause [2.13.2, critical Construct].

- Parsing/semantic analysis of all non-offloading directives introduced in OpenMP 4.5.

The codegen for OpenMP constructs was significantly improved allowing to produce much more stable and fast code.

Could you add it to your patch?

[kkwli0]

OpenMP spec uses the term "device constructs". How about using "non-device directives" instead of "non-offloading directives"?

[andreybokhanko]

Along with Alexey's addition, this looks good.

(Don't treat my approval as "LGTM", though -- as I don't have authority for this.)

Yours,
Andrey

[guansong]

Should we mention that the runtime can be built "in-tree" as well? This simplifies users experience to access OpenMP support.

I did a test. I found the library is built as expected. Without installation process, it can not be used directly. People can then set environment vars to use the header file and the library.

I am not sure how each Linux distribution handle this. For example, when you do apt-get install clang, will the OpenMP runtime be part of it?

[• fraggamuffin]

Ok, just adding that the runtime can be built in-tree. I will upstream tonight at 7 pm ET.

[hans]

In D17323#358115, @fraggamuffin wrote:

Ok, just adding that the runtime can be built in-tree. I will upstream tonight at 7 pm ET.

Looks like this was committed in r261526. Thanks!

docs/ReleaseNotes.rst

- A set of floating point arithmetic relaxation flags: ``-cl-no-signed-zeros``,
   ``-cl-fast-relaxed-math``.
 
 - Added ``^^`` to the list of reserved operations.
 
 - Improved vector support and diagnostics.
 
 - Improved diagnostics for function pointers.
 
+OpenMP Support in Clang
+---------------------
+
+OpenMP 3.1 is fully supported and is enabled by default with -fopenmp 
+which now uses the clang OpenMP library instead of the GCC OpenMP library.
+The runtime can be built in-tree.  
+
+In addition to OpenMP 3.1, several important elements of the OpenMP 4.0/4.5 
+are supported as well. We continue to aim to complete OpenMP 4.5
+
+- ``map`` clause
+- task dependencies
+- ``num_teams`` clause
+- ``thread_limit`` clause
+- ``target`` and ``target data`` directive
+- ``target`` directive with implicit data mapping
+- ``target enter data`` and ``target exit data`` directive
+- Array sections [2.4, Array Sections].
+- Directive name modifiers for ``if`` clause [2.12, if Clause].
+- ``linear`` clause can be used in loop-based directives [2.7.2, loop Construct].
+- ``simdlen`` clause [2.8, SIMD Construct].
+- ``hint`` clause [2.13.2, critical Construct].
+- Parsing/semantic analysis of all non-device directives introduced in OpenMP 4.5.
+
+The codegen for OpenMP constructs was significantly improved allowing us to produce much more stable and fast code.
+Full test cases of IR are also implemented.
+
 CUDA Support in Clang
 ---------------------
 Clang has experimental support for end-to-end CUDA compilation now:
 
 - The driver now detects CUDA installation, creates host and device compilation
   pipelines, links device-side code with appropriate CUDA bitcode and produces
   single object file with host and GPU code.