[llvm] [ConstantFold] Fold `logb` and `logbf` when the input parameter is a constant value. (PR #111232)

[via llvm-commits]

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@@ -1676,9 +1676,9 @@ bool llvm::canConstantFoldCallTo(const CallBase *Call, const Function *F) {
            Name == "floor" || Name == "floorf" ||
            Name == "fmod" || Name == "fmodf";
   case 'l':
-    return Name == "log" || Name == "logf" || Name == "log2" ||
-           Name == "log2f" || Name == "log10" || Name == "log10f" ||
-           Name == "logl";
+    return Name == "log" || Name == "logf" || Name == "logl" ||
+           Name == "log2" || Name == "log2f" || Name == "log10" ||
+           Name == "log10f" || Name == "logb" || Name == "logbf";
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c8ef wrote:

I plan to postpone `logl` in later patches because the handling of the long double parameter differs from these two functions. Additionally, even though the `logl` function is included here, we are still unable to perform constant folding on it at this time: https://godbolt.org/z/3GcnzMexd.

https://github.com/llvm/llvm-project/pull/111232