[PATCH] D27492: [DWARF] Suppress .loc directives coming from CFI instructions

[Adrian Prantl via llvm-commits]

> On Dec 9, 2016, at 12:48 PM, Paul Robinson via Phabricator <reviews at reviews.llvm.org> wrote:
> 
> probinson added inline comments.
> 
> 
> ================
> Comment at: test/DebugInfo/Generic/no-cfi-loc.ll:2
> +; RUN: %llc_dwarf -filetype=asm -use-unknown-locations < %s | FileCheck %s
> +; CHECK-NOT: .loc 1 0 0
> +
> ----------------
> aprantl wrote:
>> probinson wrote:
>>> aprantl wrote:
>>>> Short comment on what is being checked here?
>>>> And is there anything positive that could be checked for, too? Tests that only CHECK-NOT love to break without anybody noticing :-)
>>> It ends up emitting a CFI instruction with no debug location. The test is verifying that this does not result in a line-0 record (that we skip the CFI instruction).
>>> 
>>> Although, I now realize the fact that there is a CFI instruction at all is not obvious!  Maybe I should turn this into an MIR test instead.
>> My main point was that a test like this would work even if you symlink llc to /usr/bin/true. I would suggest to at least check for the function label and one other .loc directive that is expected to be in the output.
> Sorry, didn't see this before I committed.  The new test does look for the .cfi directive, and verifies  that no line-0 directive appears before that.
> I could add more positive checks if you think that would be more robust.
> 

I think that should work.

-- adrian
> 
> 
> Repository:
>  rL LLVM
> 
> https://reviews.llvm.org/D27492
> 
> 
>