[llvm] r368339 - [MBP] Disable aggressive loop rotate in plain mode

[Carrot Wei via llvm-commits]

Jeremy,
thank you for the fixing. I tried the latest LiveDebugValue.cpp with
this MBP patch, the compiler doesn't crash now.
I have another question for this file. There are following code in
function LiveDebugValues::transferSpillOrRestoreInst,

 854     } else if (TKind == TransferKind::TransferRestore &&
 855                VarLocIDs[ID].Loc.SpillLocation == *Loc) {
 856       LLVM_DEBUG(dbgs() << "Restoring Register " << printReg(Reg,
TRI) << '('
 857                         << VarLocIDs[ID].Var.getVar()->getName() << ")\n");

There is no checking of VarLocIDs[ID].Kind before the usage of
VarLocIDs[ID].Loc.SpillLocation, is this another bug?

Hans,
Although lld-linke doesn't crash, it gave many error messages like the following

lld-link: error: Cannot use debug info for
'libcmt.lib(new_scalar.obj)' [LNK4099]
>>> failed to load reference 'd:\agent\_work\3\s\binaries\x86ret\lib\i386\libcmt.i386.pdb': No such file or directory

Is it expected?

thanks

On Mon, Aug 19, 2019 at 1:47 AM Jeremy Morse
<jeremy.morse.llvm at gmail.com> wrote:
>
> Ooof, this is PR42773 [0], a patch for which landed on Thursday
> (r369026), pull-up to LLVM-9 in [1]. I've good confidence this should
> now work, the diagnosis in the thread above matches the situation in
> [0].
>
> It was most definitely a debug-info / LiveDebugValues bug; sorry I
> didn't pick up this thread earlier, I've been out-of-office and my
> llvm-commits filter-fu is poor.
>
> [0] https://bugs.llvm.org/show_bug.cgi?id=42773
> [1] https://bugs.llvm.org/show_bug.cgi?id=43018
>
> --
> Thanks,
> Jeremy