[llvm] b68eeff - [X86] Cleanup a comment around bitcasting X86ISD::VBROADCAST_LOAD and add an assert to make sure memory VT size doesn't change.

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2020-02-28T15:07:49-08:00
New Revision: b68eeff05ca0e95f8b244edfcf21ad950896091b

URL: https://github.com/llvm/llvm-project/commit/b68eeff05ca0e95f8b244edfcf21ad950896091b
DIFF: https://github.com/llvm/llvm-project/commit/b68eeff05ca0e95f8b244edfcf21ad950896091b.diff

LOG: [X86] Cleanup a comment around bitcasting X86ISD::VBROADCAST_LOAD and add an assert to make sure memory VT size doesn't change.

Added: 
    

Modified: 
    llvm/lib/Target/X86/X86ISelLowering.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 94216c09038c..d528e4921978 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -37138,10 +37138,12 @@ static SDValue combineBitcast(SDNode *N, SelectionDAG &DAG,
                        DAG.getBitcast(MVT::i16, N0.getOperand(0)));
 
   // Combine (bitcast (vbroadcast_load)) -> (vbroadcast_load). The memory VT
-  // determines // the number of bits loaded. Remaining bits are zero.
+  // determines the number of bits loaded.
   if (N0.getOpcode() == X86ISD::VBROADCAST_LOAD && N0.hasOneUse() &&
       VT.getScalarSizeInBits() == SrcVT.getScalarSizeInBits()) {
     auto *BCast = cast<MemIntrinsicSDNode>(N0);
+    assert(VT.getScalarSizeInBits() == BCast->getMemoryVT().getSizeInBits() &&
+           "Unexpected load size!");
     SDVTList Tys = DAG.getVTList(VT, MVT::Other);
     SDValue Ops[] = { BCast->getChain(), BCast->getBasePtr() };
     SDValue ResNode =