[llvm] [DFAJumpThreading] Enable the pass by default (PR #83033)

[Nikita Popov via llvm-commits]

nikic wrote:

New compile-time: https://llvm-compile-time-tracker.com/compare.php?from=29b92d07746fac26cd64c914bc9c5c3833974f6d&to=bcc333192cfadbe63154294b8606fba53247c7fd&stat=instructions:u

The results on CTMark look reasonable. Clang has two big regressions:
```
lib/DebugInfo/PDB/CMakeFiles/LLVMDebugInfoPDB.dir/Native/NativeInlineSiteSymbol.cpp.o 	5979M 	7853M (+31.34%)
tools/clang/lib/AST/CMakeFiles/obj.clangAST.dir/ByteCode/Interp.cpp.o 	39908M 	43794M (+9.74%)
```



https://github.com/llvm/llvm-project/pull/83033