[llvm] [MacroFusion] Restricts pairs to have SDep::Data dependency only (PR #203793)

[Nathan Corbyn via llvm-commits]

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@@ -0,0 +1,37 @@
+# REQUIRES: asserts
+
+## Check that we dont fuse non-RAW dependent pairs.
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cofibrant wrote:

```suggestion
## Check that we don't fuse non-RAW dependent pairs.
```

https://github.com/llvm/llvm-project/pull/203793