[llvm] r364328 - [FPEnv] A missing crucial step was undocumented.

[Kevin P. Neal via llvm-commits]

Author: kpn
Date: Tue Jun 25 09:09:39 2019
New Revision: 364328

URL: http://llvm.org/viewvc/llvm-project?rev=364328&view=rev
Log:
[FPEnv] A missing crucial step was undocumented.


Modified:
    llvm/trunk/docs/AddingConstrainedIntrinsics.rst

Modified: llvm/trunk/docs/AddingConstrainedIntrinsics.rst
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/AddingConstrainedIntrinsics.rst?rev=364328&r1=364327&r2=364328&view=diff
==============================================================================
--- llvm/trunk/docs/AddingConstrainedIntrinsics.rst (original)
+++ llvm/trunk/docs/AddingConstrainedIntrinsics.rst Tue Jun 25 09:09:39 2019
@@ -81,6 +81,14 @@ be properly handled.::
 
   lib/CodeGen/SelectionDAG/SelectionDAG.cpp
 
+However, the mutation may not happen if the new node has not been registered
+in TargetLoweringBase::initActions(). If the corresponding non-STRICT node
+is Legal but a target does not know about STRICT nodes then the STRICT
+node will default to Legal and mutation will be bypassed with a "Cannot
+select" error. Register the new STRICT node as Expand to avoid this bug.::
+
+  lib/CodeGen/TargetLoweringBase.cpp
+
 To make debug logs readable it is helpful to update the SelectionDAG's
 debug logger:::