[llvm] r293900 - [SystemZ] Add comment for ISD::FP_TO_UINT expansion.

[Jonas Paulsson via llvm-commits]

Author: jonpa
Date: Thu Feb  2 09:42:14 2017
New Revision: 293900

URL: http://llvm.org/viewvc/llvm-project?rev=293900&view=rev
Log:
[SystemZ] Add comment for ISD::FP_TO_UINT expansion.

(Copied from the fp-conv-10.ll test to SystemZISelLowering.cpp)

Review: Ulrich Weigand

Modified:
    llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp

Modified: llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp?rev=293900&r1=293899&r2=293900&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZISelLowering.cpp Thu Feb  2 09:42:14 2017
@@ -194,6 +194,9 @@ SystemZTargetLowering::SystemZTargetLowe
       setOperationAction(ISD::UMUL_LOHI, VT, Custom);
 
       // Only z196 and above have native support for conversions to unsigned.
+      // On z10, promoting to i64 doesn't generate an inexact condition for
+      // values that are outside the i32 range but in the i64 range, so use
+      // the default expansion.
       if (!Subtarget.hasFPExtension())
         setOperationAction(ISD::FP_TO_UINT, VT, Expand);
     }