How to detect New Instruction support in the Haswell/Broadwell generation Intel® Core™ processor family

Dear Support,

I have used this piece of code in the following link for a while to detect the support of new instructions across the board with different compilers (Intel, GCC, PGI). What I am looking for is a feedback and may be an updated piece of code to detect the support for the new ISA in the haswell/broadwell processors for example "Intel(R) Xeon(R) CPU E7-8891 v3 @ 2.80GHz". 

https://software.intel.com/en-us/articles/how-to-detect-new-instruction-support-in-the-4th-generation-intel-core-processor-family

Also could you please comment on how much does Intel compilers rely on GNU assemblers to provide various support to the hardware feature sets. Or is it just Intel makes it binary compatible to work with GNU, and rely's on its own assembler to produce its object codes?

Any help is greatly appreciated.

thank you,
Amit