[llvm] [IR] Add getDataLayout() helpers to Function and GlobalValue (PR #96919)

[Yingwei Zheng via llvm-commits]

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@@ -1815,7 +1815,7 @@ bool MemCpyOptPass::processMemMove(MemMoveInst *M) {
 
 /// This is called on every byval argument in call sites.
 bool MemCpyOptPass::processByValArgument(CallBase &CB, unsigned ArgNo) {
-  const DataLayout &DL = CB.getCaller()->getParent()->getDataLayout();
+  const DataLayout &DL = CB.getCaller()->getDataLayout();
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dtcxzyw wrote:

```suggestion
  const DataLayout &DL = CB.getDataLayout();
```

https://github.com/llvm/llvm-project/pull/96919