[Boost-commit] svn:boost r78189 - trunk/libs/context/doc

Subject: [Boost-commit] svn:boost r78189 - trunk/libs/context/doc
From: oliver.kowalke_at_[hidden]
Date: 2012-04-25 01:51:25

Author: olli
Date: 2012-04-25 01:51:24 EDT (Wed, 25 Apr 2012)
New Revision: 78189
URL: http://svn.boost.org/trac/boost/changeset/78189

Log:
context: documentation regarding to fpu preserving

Text files modified: 
   trunk/libs/context/doc/fcontext.qbk |    11 +++++++++++                             
   1 files changed, 11 insertions(+), 0 deletions(-)

Modified: trunk/libs/context/doc/fcontext.qbk
==============================================================================
--- trunk/libs/context/doc/fcontext.qbk	(original)
+++ trunk/libs/context/doc/fcontext.qbk	2012-04-25 01:51:24 EDT (Wed, 25 Apr 2012)
@@ -178,6 +178,17 @@
 If the __context_fn__ emits an exception, the application will terminate.
 
 
+[heading Preserving floating point registers]
+
+Preserving the floating point registers increases the cycle count for a context
+switch (see performance tests).
+The foruth argument of __jump_fcontext__ controls if fpu registers should be 
+preserved by the context jump.
+
+[important The use of the fpu controling argument of __jump_fcontext__ must
+be consistent in the application. Otherwise the behaviour is undefined.]
+
+
 [heading Stack unwinding]
 
 Sometimes it is necessary to unwind the stack of an unfinished context to