[llvm] r350684 - Remove check for single use in ShrinkDemandedConstant

[Stanislav Mekhanoshin via llvm-commits]

Author: rampitec
Date: Tue Jan  8 18:24:22 2019
New Revision: 350684

URL: http://llvm.org/viewvc/llvm-project?rev=350684&view=rev
Log:
Remove check for single use in ShrinkDemandedConstant

This removes check for single use from general ShrinkDemandedConstant
to the BE because of the AArch64 regression after D56289/rL350475.

After several hours of experiments I did not come up with a testcase
failing on any other targets if check is not performed.

Moreover, direct call to ShrinkDemandedConstant is not really needed
and superceed by SimplifyDemandedBits.

Differential Revision: https://reviews.llvm.org/D56406

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp
    llvm/trunk/lib/Target/AMDGPU/SIISelLowering.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp?rev=350684&r1=350683&r2=350684&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/TargetLowering.cpp Tue Jan  8 18:24:22 2019
@@ -350,9 +350,6 @@ bool TargetLowering::ShrinkDemandedConst
   SDLoc DL(Op);
   unsigned Opcode = Op.getOpcode();
 
-  if (!Op.hasOneUse())
-    return false;
-
   // Do target-specific constant optimization.
   if (targetShrinkDemandedConstant(Op, Demanded, TLO))
     return TLO.New.getNode();

Modified: llvm/trunk/lib/Target/AMDGPU/SIISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/SIISelLowering.cpp?rev=350684&r1=350683&r2=350684&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/SIISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/SIISelLowering.cpp Tue Jan  8 18:24:22 2019
@@ -8586,8 +8586,7 @@ SDValue SITargetLowering::performCvtF32U
   TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
                                         !DCI.isBeforeLegalizeOps());
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
-  if (TLI.ShrinkDemandedConstant(Src, Demanded, TLO) ||
-      TLI.SimplifyDemandedBits(Src, Demanded, Known, TLO)) {
+  if (TLI.SimplifyDemandedBits(Src, Demanded, Known, TLO)) {
     DCI.CommitTargetLoweringOpt(TLO);
   }