Force the DJB hash seed to 0 for compatibility with HashString. #14890
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The obsolete llvm::HashString() was equivalent to llvm::djbHash(seed=0) and was removed from llvm. This patch replaces all occurences of llvm::HashString() with llvm::djbHash(seed=0), no functional change. The default seed of llvm::djbHash() is supposed to yield a higher quality result that using seed=0, but changing it looks like it affects the ordering of SIL serialization.
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LGTM. I did the same thing in LLVM where the seed affected the tests. |
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What about the apinotes code in swift-clang's upstream-with-swift branch? Should those also use seed=0? Did you file a JIRA bug report to track the FIXME's here? |
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The obsolete llvm::HashString() was equivalent to
llvm::djbHash(seed=0) and was removed from llvm. This patch replaces
all occurences of llvm::HashString() with llvm::djbHash(seed=0), no
functional change.
The default seed of llvm::djbHash() is supposed to yield a higher
quality result that using seed=0, but changing it looks like it
affects the ordering of SIL serialization.