[llvm] r292933 - Improve comment for ISD::EXTRACT_VECTOR_ELT

[Jonas Paulsson via llvm-commits]

Author: jonpa
Date: Tue Jan 24 08:21:29 2017
New Revision: 292933

URL: http://llvm.org/viewvc/llvm-project?rev=292933&view=rev
Log:
Improve comment for ISD::EXTRACT_VECTOR_ELT

The comment in ISDOpcodes.h for EXTRACT_VECTOR_ELT now explains that the high
bits are undefined if the result is extended.

Review: Hal Finkel

Modified:
    llvm/trunk/include/llvm/CodeGen/ISDOpcodes.h

Modified: llvm/trunk/include/llvm/CodeGen/ISDOpcodes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/ISDOpcodes.h?rev=292933&r1=292932&r2=292933&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/ISDOpcodes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/ISDOpcodes.h Tue Jan 24 08:21:29 2017
@@ -281,7 +281,8 @@ namespace ISD {
     /// EXTRACT_VECTOR_ELT(VECTOR, IDX) - Returns a single element from VECTOR
     /// identified by the (potentially variable) element number IDX.  If the
     /// return type is an integer type larger than the element type of the
-    /// vector, the result is extended to the width of the return type.
+    /// vector, the result is extended to the width of the return type. In
+    /// that case, the high bits are undefined.
     EXTRACT_VECTOR_ELT,
 
     /// CONCAT_VECTORS(VECTOR0, VECTOR1, ...) - Given a number of values of