[PATCH] D23384: Use a byte array as an internal buffer of BitVector.

[bryant via llvm-commits]

bryant added inline comments.

================
Comment at: include/llvm/ADT/BitVector.h:480
@@ +479,3 @@
+    return sys::getSwappedBytes(W);
+#endif
+    return W;
----------------
ruiu wrote:
> bryant wrote:
> > ruiu wrote:
> > > ruiu wrote:
> > > > I used getSwappedBytes instead.
> > > How does it work? What is `WW`?
> > typo. i meant `W`. as for how it works:
> > 
> > ```
> >   explicit packed_endian_specific_integral(value_type val) { *this = val; }
> > 
> >   operator value_type() const {
> >     return endian::read<value_type, endian, alignment>(
> >       (const void*)Value.buffer);
> >   }
> > ```
> Is it different from
> 
>   return *(WordLE *)((void *)&W)
> 
> ?
unfortunately, that would also be ub.


https://reviews.llvm.org/D23384