[llvm] [X86] combineINSERT_SUBVECTOR - use getBROADCAST_LOAD helper in insert_subvector(undef, broadcast(p), hi) -> broadcast(p) fold (PR #128900)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-x86

Author: Simon Pilgrim (RKSimon)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/128900.diff


1 Files Affected:

- (modified) llvm/lib/Target/X86/X86ISelLowering.cpp (+2-8) 


``````````diff
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 9a259fef719f5..0dc73bbf8e3f9 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -58555,14 +58555,8 @@ static SDValue combineINSERT_SUBVECTOR(SDNode *N, SelectionDAG &DAG,
   if (Vec.isUndef() && IdxVal != 0 && SubVec.hasOneUse() &&
       SubVec.getOpcode() == X86ISD::VBROADCAST_LOAD) {
     auto *MemIntr = cast<MemIntrinsicSDNode>(SubVec);
-    SDVTList Tys = DAG.getVTList(OpVT, MVT::Other);
-    SDValue Ops[] = { MemIntr->getChain(), MemIntr->getBasePtr() };
-    SDValue BcastLd =
-        DAG.getMemIntrinsicNode(X86ISD::VBROADCAST_LOAD, dl, Tys, Ops,
-                                MemIntr->getMemoryVT(),
-                                MemIntr->getMemOperand());
-    DAG.ReplaceAllUsesOfValueWith(SDValue(MemIntr, 1), BcastLd.getValue(1));
-    return BcastLd;
+    return getBROADCAST_LOAD(X86ISD::VBROADCAST_LOAD, dl, OpVT,
+                             MemIntr->getMemoryVT(), MemIntr, 0, DAG);
   }
 
   // If we're splatting the lower half subvector of a full vector load into the

``````````

</details>


https://github.com/llvm/llvm-project/pull/128900