[clang] [CIR] Fold load from constant alloca slots (PR #212284)

[Sirui Mu via cfe-commits]

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@@ -32,6 +33,68 @@ namespace mlir {
 
 namespace {
 
+/// Find the `cir.store` operation that stores to the given alloca and dominates
+/// the given load operation. Dominance calculation is done through the given
+/// DominanceInfo object.
+///
+/// Return nullptr if no such store operation exists. If multiple store
+/// operations satisfy the criteria, any of them may be returned.
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Lancern wrote:

Yeah, I just realized that it's OK to return any of them if multiple stores are present, as long as the returned one dominates the load.

https://github.com/llvm/llvm-project/pull/212284