Hash function change in swift

[bkolb]

New versions of swift seem to use a different hashing strategy. It is incompatible with

index-import/index-import.cpp

Line 129 in 40dea41

llvm::hash_code pathHashVal = llvm::hash_value(absPath);

Here is the change: swiftlang/swift#77116

[bkolb]

The relevant change seems to be
https://github.com/swiftlang/llvm-project/pull/9140/files#diff-dcdee0465a74e090b01bd5bd0d214f65f430f25a56b837ab627966318de1ff27R289

-  llvm::hash_code PathHashVal = llvm::hash_value(RemappedPath);
-  llvm::APInt(64, PathHashVal).toString(Str, 36, /*Signed=*/false);
+  auto PathHashVal = llvm::xxh3_64bits(RemappedPath);
+  llvm::APInt(64, PathHashVal).toStringUnsigned(Str, /*Radix*/ 36);

[bkolb]

I am not the expert on this, but maybe it would be better to use this somehow instead:
https://github.com/swiftlang/indexstore-db/blob/main/Sources/IndexStoreDB_Index/include/IndexStoreDB_Index/indexstore_functions.h