SuccessChanges

Summary

  1. [lldb] Improve test failure reporting for expect() (details)
  2. [PassManager] Move load/store motion pass after DSE in LTO pipeline. (details)
Commit 9f18f3c858d5ff8154701a50c2be6f7b19667a1d by david.spickett
[lldb] Improve test failure reporting for expect()

This updates the errors reported by expect()
to something like:

```
Ran command:
"help"

Got output:
Debugger commands:
<...>

Expecting start string: "Debugger commands:" (was found)
Expecting end string: "foo" (was not found)
```
(see added tests for more examples)

This shows the user exactly what was run,
what checks passed and which failed. Along with
whether that check was supposed to pass.
(including what regex patterns matched)

These lines are also output to the test
trace file, whether the test passes or not.

Note that expect() will still fail at the first failed
check, in line with previous behaviour.

Also I have flipped the wording of the assert
message functions (.*_MSG) to describe failures
not successes. This makes more sense as they are
only shown on assert failures.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D86792
The file was addedlldb/test/API/assert_messages_test/TestAssertMessages.py
The file was modifiedlldb/packages/Python/lldbsuite/test/lldbtest.py (diff)
Commit 6de51189b07bbae853cc7c053dfb5f383c308c76 by flo
[PassManager] Move load/store motion pass after DSE in LTO pipeline.

As far as I am aware, the placement of MergedLoadStoreMotion in the
pipeline is not heavily tuned currently. It seems to not matter much if
we do it after DSE in the LTO pipeline (no binary changes for -O3 -flto
on MultiSource/SPEC2000/SPEC2006). Moving it after DSE however has a
major benefit: MemorySSA is constructed by LICM and is consumed by DSE,
so if MergedLoadStoreMotion happens after DSE, we do not need to
preserve MemorySSA in it.

If there are any concerns with this move, I can also update
MergedLoadStoreMotion to preserve MemorySSA.

This patch together with D86651 (preserve MemSSA in MemCpyOpt) and
D86534 (preserve MemSSA in GVN) are the remaining patches to bring down
compile-time for DSE + MemorySSA to the levels outlined in
http://lists.llvm.org/pipermail/llvm-dev/2020-August/144417.html

Once they land, we should be able to start with flipping the switch on
enabling DSE + MmeorySSA.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86967
The file was modifiedllvm/lib/Transforms/IPO/PassManagerBuilder.cpp (diff)