This patch makes the final major change of the RemoveDIs project, changing the
default IR output from debug intrinsics to debug records. This is expected to
break a large number of tests: every single one that tests for uses or
declarations of debug intrinsics and does not explicitly disable writing
records. 

If this patch has broken your downstream tests (or upstream tests on a
configuration I wasn't able to run):
1. If you need to immediately unblock a build, pass
`--write-experimental-debuginfo=false` to LLVM's option processing for all
failing tests (remember to use `-mllvm` for clang/flang to forward arguments to
LLVM).
2. For most test failures, the changes are trivial and mechanical, enough that
they can be done by script; see the migration guide for a guide on how to do
this: https://llvm.org/docs/RemoveDIsDebugInfo.html#test-updates
3. If any tests fail for reasons other than FileCheck check lines that need
updating, such as assertion failures, that is most likely a real bug with this
patch and should be reported as such.

For more information, see the recent PSA:
https://discourse.llvm.org/t/psa-ir-output-changing-from-debug-intrinsics-to-debug-records/79578

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.
After fixing problems in LiveDebugVariables.
After fixing NULL symbol problems in AddressPool when enabling
split-dwarf-file.
After fixing PR39094.
After landing D54199 and D54465 to fix Chromium build failed.

Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 352025

This broke the Chromium build. See
https://bugs.chromium.org/p/chromium/issues/detail?id=898152#c1 for the
reproducer.

> Generate DILabel metadata and call llvm.dbg.label after label
> statement to associate the metadata with the label.
>
> After fixing PR37395.
> After fixing problems in LiveDebugVariables.
> After fixing NULL symbol problems in AddressPool when enabling
> split-dwarf-file.
> After fixing PR39094.
>
> Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 345026

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.
After fixing problems in LiveDebugVariables.
After fixing NULL symbol problems in AddressPool when enabling
split-dwarf-file.
After fixing PR39094.

Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 345009

This reverts commit r343148.

It crashes on sanitizer-x86_64-linux-autoconf.

llvm-svn: 343183

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.
After fixing problems in LiveDebugVariables.
After fixing NULL symbol problems in AddressPool when enabling
split-dwarf-file.

Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 343148

This reverts commit r341519, which generates debug info that causes
backend crashes. (with -split-dwarf-file)

Details in https://reviews.llvm.org/D50495

llvm-svn: 341549

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.
After fixing problems in LiveDebugVariables.

Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 341519

Build failed in
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/27258

In lib/CodeGen/LiveDebugVariables.cpp:589, it uses std::prev(MBBI) to
get DebugValue's SlotIndex. however, the previous instruction may be
also a debug instruction.

llvm-svn: 338992

Generate DILabel metadata and call llvm.dbg.label after label
statement to associate the metadata with the label.

After fixing PR37395.

Differential Revision: https://reviews.llvm.org/D45045

llvm-svn: 338989