[PATCH] [PATCH][X86] Slightly refactor default features for AMD bdver* cpus. Also improve checks for target features in test Preprocessor/predefined-arch-macros.c.

[Andrea Di Biagio]

>>! In D6134#4, @craig.topper wrote:
> Why have avx, fma4, and sse4a been added to CK_BDVER1? xop implies all of
> those. Can we use comments instead?

Sure, I will remove the redundant calls to setFeatureEnabledImpl that set avx,fma4,sse4a.
I originally added those features mainly for clarity reason (to make more explicit that the target has avx). I agree that adding a comment is much better.
I will add a comment on top of the call that sets feature 'xop' for bdver1 that simply says "xop implies avx, fma4 and sse4a".

http://reviews.llvm.org/D6134