[llvm] [DAG] shouldReduceLoadWidth - hasOneUse should check just the loaded value - not the chain (PR #128167)

[Simon Pilgrim via llvm-commits]

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@@ -1817,7 +1817,7 @@ class TargetLoweringBase {
                                      EVT NewVT) const {
     // By default, assume that it is cheaper to extract a subvector from a wide
     // vector load rather than creating multiple narrow vector loads.
-    if (NewVT.isVector() && !Load->hasOneUse())
+    if (NewVT.isVector() && !Load->hasNUsesOfValue(1, 0))
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RKSimon wrote:

Yeah, we can do that (its what SDValue::hasOneUse calls anyway) - doesn't fix the dependency failure though.

Also - why does shouldReduceLoadWidth take a SDNode and not the SDValue?

https://github.com/llvm/llvm-project/pull/128167