[cfe-commits] r72718 - /cfe/trunk/include/clang/AST/Builtins.def

[Chris Lattner]

On Jun 2, 2009, at 10:45 AM, Eli Friedman wrote:
>>> URL: http://llvm.org/viewvc/llvm-project?rev=72718&view=rev
>>> Log:
>>> Add builtin declarations for the variants of sin and cos.
>>
>> Nice.  I don't think sin/cos set errno though, unlike sqrt.  Aren't  
>> they
>> const functions?
>
> I don't think glibc sets it, but I don't know about other
> implementations; see
> http://opengroup.org/onlinepubs/007908775/xsh/sin.html .

Getting sin/cos set to be readnone at the codegen level is really  
important for performance.  How should we handle this on targets where  
it is safe?  On MacOS, none of the libm functions set errno, but with  
glibc things are more complex.

-Chris