Move over some more checks from `DIDescriptor::Verify()`, and change
`LLParser` to require non-null `file:` fields in compile units.
I've ignored the comment in test/Assembler/metadata-null-operands.ll
since I disagree with it. At the time that test was written (r229960),
the debug info verifier wasn't on by default, so my comment there is in
the context of not expecting the verifier to be useful. It is now, and
besides that, since r233394 we can check when parsing textual IR whether
an operand is null that shouldn't be.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233654 91177308-0d34-0410-b5e6-96231b3b80d8
When writing the bitcode serialization for the new debug info hierarchy,
I assumed two fields would never be null.
Drop that assumption, since it's brittle (and crashes the
`BitcodeWriter` if wrong), and is a check better left for the verifier
anyway. (No need for a bitcode upgrade here, since the new hierarchy is
still not in place.)
The fields in question are `MDCompileUnit::getFile()` and
`MDDerivedType::getBaseType()`, the latter of which isn't null in
test/Transforms/Mem2Reg/ConvertDebugInfo2.ll (see !14, a pointer to
nothing). While the testcase might have bitrotted, there's no reason
for the bitcode format to rely on non-null for metadata operands.
This also fixes a bug in `AsmWriter` where if the `file:` is null it
isn't emitted (caught by the double-round trip in the testcase I'm
adding) -- this is a required field in `LLParser`.
I'll circle back to ConvertDebugInfo2. Once the specialized nodes are
in place, I'll be trying to turn the debug info verifier back on by
default (in the newer module pass form committed r206300) and throwing
more logic in there. If the testcase has bitrotted (as opposed to me
not understanding the schema correctly) I'll fix it then.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229960 91177308-0d34-0410-b5e6-96231b3b80d8
