[llvm] [X86] combineConcatVectorOps - add concatenation handling for BITCAST + AssertSext/AssertZext nodes (PR #133913)

[Simon Pilgrim via llvm-commits]

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@@ -58134,6 +58135,40 @@ static SDValue combineConcatVectorOps(const SDLoc &DL, MVT VT,
 
     unsigned Opcode = Op0.getOpcode();
     switch (Opcode) {
+    case ISD::AssertSext:
+    case ISD::AssertZext: {
+      if (!IsSplat && llvm::all_of(Ops, [Op0](SDValue Op) {
+            return Op0.getOperand(1) == Op.getOperand(1);
+          }))
+        if (SDValue ConcatSrc =
+                combineConcatVectorOps(DL, VT, Ops, DAG, Subtarget, Depth + 1))
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RKSimon wrote:

Looks like this was dead code - I'm going to remove it.

https://github.com/llvm/llvm-project/pull/133913