Here we have implemented the following missing trigonometric optimizations.
1. tan(x)*cos(x)=sin(x)
2. sin(x)*cos(x) = sin(2*x)/2
3. sin(x)/tan(x)=cos(x);
4. tan(x)/sin(x)=1/cos(x);
Here is the reference to the missing optimization reported on bugzilla.
https://bugs.llvm.org/show_bug.cgi?id=35602