basic properties of floor and ceiling function

[k-arrows]

There are other formulas that hold, but I'll list the basic ones.
https://alive2.llvm.org/ce/z/dQgZ84

If I understand correctly, these transformations require nnan flag.

Original functions:

#include <cmath>

bool src1(float x)
{
  return std::floor(x) <= x;
}

bool src2(float x)
{
  return x <= std::ceil(x);
}

bool src3(float x)
{
  return std::ceil(x) == -std::floor(-x);
}

bool src4(float x)
{
  return std::floor(x) == -std::ceil(-x);
}

[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:

1. In the comments of the issue, request for it to be assigned to you.
2. Fix the issue locally.
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4. Create a Git commit.
5. Run git clang-format HEAD~1 to format your changes.
6. Open a pull request to the upstream repository on GitHub. Detailed instructions can be found in GitHub's documentation.

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)

There are other formulas that hold, but I'll list the basic ones. https://alive2.llvm.org/ce/z/dQgZ84

If I understand correctly, these transformations require nnan flag.

Original functions:

#include <cmath>

bool src1(float x)
{
  return std::floor(x) <= x;
}

bool src2(float x)
{
  return x <= std::ceil(x);
}

bool src3(float x)
{
  return std::ceil(x) == -std::floor(-x);
}

bool src4(float x)
{
  return std::floor(x) == -std::ceil(-x);
}

[kevinmingtarja]

Hi, I'd like to contribute to this.

Do you have any pointers on where to start reading the code?

[dtcxzyw]

Hi, I'd like to contribute to this.

Do you have any pointers on where to start reading the code?

You should implement this in simplifyFCmpInst.

[kevinmingtarja]

Thanks for the pointer. I'll get started soon.

[Atousa]

@kevinmingtarja , I would like to work on this issue if you are not working on it?

[kevinmingtarja]

Hi @Atousa! I'm still in progress on this but just havent finished yet.

[c8ef]

Hi @kevinmingtarja, would you like me to work on this issue if you are not already working on it?