r254251 - ARM v8.1a adds Advanced SIMD instructions for Rounding Double Multiply

[Renato Golin via cfe-commits]

On 1 December 2015 at 17:23, James Molloy via cfe-commits
<cfe-commits at lists.llvm.org> wrote:
> This isn't just a NEON intrinsics thing, and this isn't just an ARM/AArch64
> thing. There needs to be some way to test the compiler from start to finish.
> Not being able to do so leaves serious coverage holes.

Just for the sake of completeness, a hole that the test-suite doesn't cover.


> CodeGen/aarch64-fix-cortex-a53-835769.c, where we absolutely 100% must
> ensure that the -mfix-cortex-a53-835769 flag gets properly respected in the
> compiler output.

SIMD intrinsics (including NEON, SSE), Errata fixes, Procedure call
tests, ELF section placement, FP contracts, Debug info, Inline
assembly, Unicode support, object creation, library symbol clashes,
back-end diagnostics are some of the examples that need to go all the
way to asm or object code.


> If you can describe a way to get the same strength of testing without
> running the backend during clang tests, I'm all ears!

I'm particularly interested in how do we keep the IR printed in the
Clang tests in sync with the IR sent to the LLVM tests if/when they
change, to guarantee that Clang changes don't generate silent codegen
faults down the line in LLVM and vice-versa.

cheers,
--renato