[PATCH] D62731: Add support for options -frounding-math, -ftrapping-math, -ffp-model=, and -ffp-exception-behavior=, : Specify floating point behavior

[Eric Christopher via cfe-commits]

You can sign up for an account by emailing the admin account.

On Thu, Dec 26, 2019, 5:04 PM Anton Yudintsev via Phabricator <
reviews at reviews.llvm.org> wrote:

> AntonYudintsev added a comment.
>
> I have found bug in clang-cl (win32 clang), related to recent inroduction
> of ffp-exception-behavior.
> Unfortunately, I don't have a working patch yet, and since LLVM bugtracker
> registration is closed, I can not even submit a bug.
>
> So, if it is not a trouble for you, I will email the bug description here.
>
> Please let me know if it isn't appropriate. Bug description:
> ============================================================
>
> Windows: clang-cl is generating call to non-existing lib function for
> win32 with /fp:except option.
> With recent ffp-exception-behavior=maytrap/strict, fp:except in clang-cl
> became generate FPE aware code.
>
> But in case of floorf and ceilf it generates call to non-existing library
> function.
>
> clang-cl.exe -m32 /Ox /fp:except testFloor.cpp /FA
> testFloor.cpp:
>
>   #include <math.h>
>   float ret(float v) {  return floorf(v); }
>
> resulting assember:
>
>   push    eax
>   movss    xmm0, dword ptr [esp + 8]
>   movss    dword ptr [esp], xmm0
>   call    _floorf #no such function!!!
>   pop    eax
>   ret
>
> Expected behaviour:
>
> there is no floorf lib function. Like with cosf and other math functions,
> floorf in MSVC is implemented as inline function.
>
> So, it should be call to _floor (with apropriate conversion first).
>
>
> Repository:
>   rG LLVM Github Monorepo
>
> CHANGES SINCE LAST ACTION
>   https://reviews.llvm.org/D62731/new/
>
> https://reviews.llvm.org/D62731
>
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20191226/6d2e7ad7/attachment.html>