scalbln(x, n), scalbn(x, n), ldexp(x, n) are not folded at the compilation time when (x, n) is constant

[k-arrows]

Consider the following example. https://godbolt.org/z/54xsG8WTr

#include <cmath>

double f1() {
  return std::scalbln(3.0, 4);
}

double f2() {
  return std::scalbn(3.0, 4);
}

double f3() {
  return std::ldexp(3.0, 4);
}

[llvmbot]

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

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3. Fix the issue locally.
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If you have any further questions about this issue, don't hesitate to ask via a comment in the thread below.

[llvmbot]

@llvm/issue-subscribers-good-first-issue

Author: None (k-arrows)

Consider the following example. https://godbolt.org/z/54xsG8WTr ```cpp #include <cmath> double f1() { return std::scalbln(3.0, 4); } double f2() { return std::scalbn(3.0, 4); } double f3() { return std::ldexp(3.0, 4); } ```

[dtcxzyw]

Should first add TLI support for scalbln/scalbn.

[arsenm]

llvm.ldexp will be constant folded. Surprisingly these are not resulting in llvm.ldexp, and are using the libcalls

[fawdlstty]

I am interested in this issue, please assign it to me. Thank you