[compiler-rt] [compiler-rt] Make sure __clzdi2 doesn't call itself recursively on sparc64 (PR #136737)

[Sergei Barannikov via llvm-commits]

s-barannikov wrote:

Note that `__ctzdi2` has a similar workaround. Currently, it doesn't call itself recursively, but it will start doing so in the future, once we teach DAG legalizer to promote 32-bit `CTTZ_ZERO_UNDEF`.


https://github.com/llvm/llvm-project/pull/136737