Attempt Github CI

[CSI] Slightly better front-end data when debug symbols cannot be found for a particular instruction or function.

[CilkSanitizer] Fixed bug causing CilkSanitizer to fail to instrument function entry/exit and free calls in some cases.

[TapirRaceDetect] Handle realloc as a special case, since it can free memory as well as allocate it.

[llvm-mode] Support syntax coloring of dso_local.

[CilkSanitizer,CSI] Fixed bug with inserting loop instrumentation and splitting detach-continuation blocks.

[TaskSimplify] Avoid removing sync regions for syncs that's don't appear distinguishing themselves but are distinguished against by other syncs.

[CilkSanitizer] Pass sync-region information to Cilksan.

[CilkSanitizer] Fixed bug where Cilksan failed to instrument loads and stores whose underlying object was a noalias function argument.

[CilkSanitizer] Avoiding unnecessary loads of suppression flags.

[CilkSanitizer] Adding Cilksan-specific attributes on CSI hooks that Ciksan uses.

[TapirRaceDetect] Improved analysis of potential races between function arguments and instructions.

[TapirRaceDetect] Bug fix to identify loops to check based on loops in common between the two accesses and their underlying objects.

[LoopStripMine] Fixed creation and updating of PHI nodes when nesting a stripmined parallel loop within a task, specifically, when spawning the epilog.

[CilkSanitizer] Add loop instrumentation.