[PATCH] D53177: [builtins] Implement __aeabi_uread4/8 and __aeabi_uwrite4/8.

[Eli Friedman via Phabricator via llvm-commits]

efriedma added a comment.

The packed/may_alias struct pattern is the same pattern we use in the x86 immintrin.h for unaligned loads; should do the right thing in general.

> Does packed always means alignment of 1?

Yes.

> And is the mayalias needed if the thing we are aliasing with is a char*?

Well, if we're not doing LTO with compiler-rt (which isn't really something we support anyway), the may_alias does nothing because there aren't any other memory accesses.  The type of the pointer isn't really relevant.

----

> Write functions return the value written

Oh, oops, will fix.


Repository:
  rCRT Compiler Runtime

https://reviews.llvm.org/D53177