[llvm-branch-commits] [cfe-branch] r230294 - Add release notes about the unroll pragmas.

Mark Heffernan meheff at google.com
Mon Feb 23 17:14:35 PST 2015


Author: meheff
Date: Mon Feb 23 19:14:35 2015
New Revision: 230294

URL: http://llvm.org/viewvc/llvm-project?rev=230294&view=rev
Log:
Add release notes about the unroll pragmas.


Modified:
    cfe/branches/release_36/docs/ReleaseNotes.rst

Modified: cfe/branches/release_36/docs/ReleaseNotes.rst
URL: http://llvm.org/viewvc/llvm-project/cfe/branches/release_36/docs/ReleaseNotes.rst?rev=230294&r1=230293&r2=230294&view=diff
==============================================================================
--- cfe/branches/release_36/docs/ReleaseNotes.rst (original)
+++ cfe/branches/release_36/docs/ReleaseNotes.rst Mon Feb 23 19:14:35 2015
@@ -84,7 +84,17 @@ To reliably test if C++ exceptions are e
 New Pragmas in Clang
 -----------------------
 
-Clang now supports the ...
+Clang now supports the `#pragma unroll` and `#pragma nounroll` directives to
+specify loop unrolling optimization hints.  Placed just prior to the desired
+loop, `#pragma unroll` directs the loop unroller to attempt to fully unroll the
+loop.  The pragma may also be specified with a positive integer parameter
+indicating the desired unroll count: `#pragma unroll _value_`.  The unroll count
+parameter can be optionally enclosed in parentheses. The directive `#pragma
+nounroll` indicates that the loop should not be unrolled.  These unrolling hints
+may also be expressed using the `#pragma clang loop` directive.  See the Clang
+`language extensions
+<http://clang.llvm.org/docs/LanguageExtensions.html#extensions-for-loop-hint-optimizations>`_
+for details.
 
 Windows Support
 ---------------





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