[PATCH] STLExtras: Provide less/equal functors with templated function call operators, plus a deref'ing functor template utility

[Duncan P. N. Exon Smith]

> On 2015 Feb 1, at 16:02, David Blaikie <dblaikie at gmail.com> wrote:
> 
> Formatting and comments
> 
> 
> http://reviews.llvm.org/D7324
> 
> Files:
>  include/llvm/ADT/STLExtras.h
>  utils/TableGen/CodeGenRegisters.cpp
>  utils/TableGen/CodeGenRegisters.h
>  utils/TableGen/RegisterInfoEmitter.cpp
> 
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> <D7324.19120.patch>

It's a slight shame to lose the `assert()`s in `Less` and `Equal`, but
given that we have the ASan bots they were probably low value anyway.

LGTM.