Commit Graph

14 Commits

Author SHA1 Message Date
Paul Robinson adcdc1bd0a [DebugInfo] IR/Bitcode changes for DISubprogram flags.
Packing the flags into one bitcode word will save effort in
adding new flags in the future.

Differential Revision: https://reviews.llvm.org/D54755

llvm-svn: 347806
2018-11-28 21:14:32 +00:00
Vedant Kumar 2e6c5f96dc [Debugify] Don't treat missing dbg.values as an error (PR37942)
When checking the debug info in a module, don't treat a missing
dbg.value as an error. The dbg.value may simply have been DCE'd, in
which case the debugger has enough information to display the variable
as <optimized out>.

llvm-svn: 335647
2018-06-26 18:54:10 +00:00
Vedant Kumar 77f4d4d8aa [Debugify] Skip dbg.value placement for EH pads, musttail
Placing meta-instructions into EH pads breaks certain IR invariants, as
does placing instructions after a musttail call.

llvm-svn: 333856
2018-06-03 22:50:22 +00:00
Vedant Kumar 4872535eb9 [Debugify] Set a DI version module flag for llc compatibility
Setting the "Debug Info Version" module flag makes it possible to pipe
synthetic debug info into llc, which is useful for testing backends.

llvm-svn: 333237
2018-05-24 23:00:23 +00:00
Vedant Kumar b70e35686b [Debugify] Avoid printing unnecessary square braces, NFC
llvm-svn: 333236
2018-05-24 23:00:22 +00:00
Anastasis Grammenos d6c6678766 [Debugify] Print the output to stderr
Currently debugify prints it's output to stdout,
with this patch all the output generated goes to stderr.

This change lets us use debugify without taking away
the ability to pipe the output to other llvm tools.

llvm-svn: 332642
2018-05-17 18:19:58 +00:00
Anastasis Grammenos b4344c66aa [Debugfiy] Print the pass name next to the result
CheckDebugify now prints the pass name right next to the result of the check.

Differential Revision: https://reviews.llvm.org/D46908

llvm-svn: 332416
2018-05-15 23:38:05 +00:00
Vedant Kumar 595ba1d548 [Debugify] Add -debugify-each for testing each pass in a pipeline
This adds a -debugify-each mode to opt which, when enabled, wraps each
{Module,Function}Pass in a pipeline with logic to add, check, and strip
synthetic debug info for testing purposes.

This mode can be used to test complex pipelines for debug info bugs, or
to collect statistics about the number of debug values & locations lost
throughout various stages of a pipeline.

Patch by Son Tuan Vu!

Differential Revision: https://reviews.llvm.org/D46525

llvm-svn: 332312
2018-05-15 00:29:27 +00:00
Shiva Chen 2c864551df [DebugInfo] Add DILabel metadata and intrinsic llvm.dbg.label.
In order to set breakpoints on labels and list source code around
labels, we need collect debug information for labels, i.e., label
name, the function label belong, line number in the file, and the
address label located. In order to keep these information in LLVM
IR and to allow backend to generate debug information correctly.
We create a new kind of metadata for labels, DILabel. The format
of DILabel is

!DILabel(scope: !1, name: "foo", file: !2, line: 3)

We hope to keep debug information as much as possible even the
code is optimized. So, we create a new kind of intrinsic for label
metadata to avoid the metadata is eliminated with basic block.
The intrinsic will keep existing if we keep it from optimized out.
The format of the intrinsic is

llvm.dbg.label(metadata !1)

It has only one argument, that is the DILabel metadata. The
intrinsic will follow the label immediately. Backend could get the
label metadata through the intrinsic's parameter.

We also create DIBuilder API for labels to be used by Frontend.
Frontend could use createLabel() to allocate DILabel objects, and use
insertLabel() to insert llvm.dbg.label intrinsic in LLVM IR.

Differential Revision: https://reviews.llvm.org/D45024

Patch by Hsiangkai Wang.

llvm-svn: 331841
2018-05-09 02:40:45 +00:00
Vedant Kumar 17d8bbac45 [Debugify] Don't check functions which were skipped
If no debug info was applied to a function, its debug info shouldn't be
checked (it doesn't have any :).

llvm-svn: 325297
2018-02-15 21:28:38 +00:00
Vedant Kumar 775c7af4f9 [opt] Port the debugify passes to the new pass manager
llvm-svn: 325294
2018-02-15 21:14:36 +00:00
Vedant Kumar 1627632c48 [Debugify] Avoid verifier failure on non-definition subprograms
If a function doesn't have an exact definition, don't apply debugify
metadata as it triggers a DIVerifier failure.

The issue is that it's invalid to have DILocations inside a DISubprogram
which isn't a definition ("scope points into the type hierarchy!").

llvm-svn: 325036
2018-02-13 18:15:27 +00:00
Vedant Kumar 92f7a6200c [Debugify] Add a mode to opt to enable faster testing
Opt's "-enable-debugify" mode adds an instance of Debugify at the
beginning of the pass pipeline, and an instance of CheckDebugify at the
end.

You can enable this mode with lit using: -Dopt="opt -enable-debugify".
Note that running test suites in this mode will result in many failures
due to strict FileCheck commands, etc.

It can be more useful to look for assertion failures which arise only
when Debugify is enabled, e.g to prove that we have (or do not have)
test coverage for some code path with debug info present.

Differential Revision: https://reviews.llvm.org/D41793

llvm-svn: 323256
2018-01-23 20:43:50 +00:00
Vedant Kumar 195dfd10a6 [Debugify] Add a pass to test debug info preservation
The Debugify pass synthesizes debug info for IR. It's paired with a
CheckDebugify pass which determines how much of the original debug info
is preserved. These passes make it easier to create targeted tests for
debug info preservation.

Here is the Debugify algorithm:

  NextLine = 1
  for (Instruction &I : M)
    attach DebugLoc(NextLine++) to I

  NextVar = 1
  for (Instruction &I : M)
    if (canAttachDebugValue(I))
      attach dbg.value(NextVar++) to I

The CheckDebugify pass expects contiguous ranges of DILocations and
DILocalVariables. If it fails to find all of the expected debug info, it
prints a specific error to stderr which can be FileChecked.

This was discussed on llvm-dev in the thread:
"Passes to add/validate synthetic debug info"

Differential Revision: https://reviews.llvm.org/D40512

llvm-svn: 320202
2017-12-08 21:57:28 +00:00