[llvm] [DAG] shouldReduceLoadWidth - add optional<unsigned> byte offset argument (PR #136723)

[Simon Pilgrim via llvm-commits]

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@@ -1346,6 +1346,9 @@ namespace llvm {
         Op = Op.getOperand(Op.getOpcode() == ISD::INSERT_SUBVECTOR ? 1 : 0);
 
       return Op.getOpcode() == X86ISD::VBROADCAST_LOAD ||
+             Op.getOpcode() == X86ISD::SUBV_BROADCAST_LOAD ||
+             (Op.getOpcode() == ISD::LOAD &&
+              getTargetConstantFromLoad(cast<LoadSDNode>(Op))) ||
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RKSimon wrote:

I've screwed up the merge somewhere (hence the test failures) - working on cleanup

https://github.com/llvm/llvm-project/pull/136723