[llvm] 931e66b - [X86] Remove extract_subvector(subv_broadcast_load()) fold.

[Simon Pilgrim via llvm-commits]

Author: Simon Pilgrim
Date: 2020-12-17T11:02:49Z
New Revision: 931e66bd899cbc10822fd80e7447eb3df0db1176

URL: https://github.com/llvm/llvm-project/commit/931e66bd899cbc10822fd80e7447eb3df0db1176
DIFF: https://github.com/llvm/llvm-project/commit/931e66bd899cbc10822fd80e7447eb3df0db1176.diff

LOG: [X86] Remove extract_subvector(subv_broadcast_load()) fold.

This was needed in an earlier version of D92645, but isn't now - and I've just noticed that it was potentially flawed depending on the relevant widths of the broadcasted and extracted subvectors.

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 5264014f2b8f..20a75cb64fa8 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -49390,8 +49390,7 @@ static SDValue combineExtractSubvector(SDNode *N, SelectionDAG &DAG,
   // extract the lowest subvector instead which should allow
   // SimplifyDemandedVectorElts do more simplifications.
   if (IdxVal != 0 && (InVec.getOpcode() == X86ISD::VBROADCAST ||
-                      InVec.getOpcode() == X86ISD::VBROADCAST_LOAD ||
-                      InVec.getOpcode() == X86ISD::SUBV_BROADCAST_LOAD))
+                      InVec.getOpcode() == X86ISD::VBROADCAST_LOAD))
     return extractSubVector(InVec, 0, DAG, SDLoc(N), SizeInBits);
 
   // If we're extracting a broadcasted subvector, just use the source.