[llvm] r191219 - Add a paragraph on prefix data layout.

[Peter Collingbourne]

Author: pcc
Date: Mon Sep 23 15:14:21 2013
New Revision: 191219

URL: http://llvm.org/viewvc/llvm-project?rev=191219&view=rev
Log:
Add a paragraph on prefix data layout.

Modified:
    llvm/trunk/docs/LangRef.rst

Modified: llvm/trunk/docs/LangRef.rst
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/LangRef.rst?rev=191219&r1=191218&r2=191219&view=diff
==============================================================================
--- llvm/trunk/docs/LangRef.rst (original)
+++ llvm/trunk/docs/LangRef.rst Mon Sep 23 15:14:21 2013
@@ -780,6 +780,11 @@ the inliner and other passes to reason a
 definition without needing to reason about the prefix data.  Obviously this
 makes the format of the prefix data highly target dependent.
 
+Prefix data is laid out as if it were an initializer for a global variable
+of the prefix data's type.  No padding is automatically placed between the
+prefix data and the function body.  If padding is required, it must be part
+of the prefix data.
+
 A trivial example of valid prefix data for the x86 architecture is ``i8 144``,
 which encodes the ``nop`` instruction: