[llvm] Move a lot of symbol code to use the symbol string pool (PR #115796)

[Lang Hames via llvm-commits]

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@@ -59,6 +59,8 @@ autoconf/autom4te.cache
 # VS2017 and VSCode config files.
 .vscode
 .vs
+#zed config files
+.zed
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lhames wrote:

Leftover change? (If this is useful we should commit it separately)

https://github.com/llvm/llvm-project/pull/115796