Overhaul the TargetMachine and LLVMTargetMachine Classes (#111234)

Following discussions in #110443, and the following earlier discussions
in https://lists.llvm.org/pipermail/llvm-dev/2017-October/

Overhaul the TargetMachine and LLVMTargetMachine Classes (#111234)

Following discussions in #110443, and the following earlier discussions
in https://lists.llvm.org/pipermail/llvm-dev/2017-October/117907.html,
https://reviews.llvm.org/D38482, https://reviews.llvm.org/D38489, this
PR attempts to overhaul the `TargetMachine` and `LLVMTargetMachine`
interface classes. More specifically:
1. Makes `TargetMachine` the only class implemented under
`TargetMachine.h` in the `Target` library.
2. `TargetMachine` contains target-specific interface functions that
relate to IR/CodeGen/MC constructs, whereas before (at least on paper)
it was supposed to have only IR/MC constructs. Any Target that doesn't
want to use the independent code generator simply does not implement
them, and returns either `false` or `nullptr`.
3. Renames `LLVMTargetMachine` to `CodeGenCommonTMImpl`. This renaming
aims to make the purpose of `LLVMTargetMachine` clearer. Its interface
was moved under the CodeGen library, to further emphasis its usage in
Targets that use CodeGen directly.
4. Makes `TargetMachine` the only interface used across LLVM and its
projects. With these changes, `CodeGenCommonTMImpl` is simply a set of
shared function implementations of `TargetMachine`, and CodeGen users
don't need to static cast to `LLVMTargetMachine` every time they need a
CodeGen-specific feature of the `TargetMachine`.
5. More importantly, does not change any requirements regarding library
linking.

cc @arsenm @aeubanks

show more ...

[NFC] Remove unused argument (FuncName) for parseMIR (#106144)

While working on a MIR unittest, I noticed that parseMIR includes an
unused argument that sets a function name. This is not only redun

[NFC] Remove unused argument (FuncName) for parseMIR (#106144)

While working on a MIR unittest, I noticed that parseMIR includes an
unused argument that sets a function name. This is not only redundant
but also irrelevant, as parseMIR is designed to parse entire module, not
specific functions, even though most unittests contain a single function
per module. To streamline the API, I have removed this unnecessary
argument from parseMIR. However, if this argument was originally
included to enhance readability or for any other purpose, please let me
know.

show more ...

[IRBuilder] Don't include Module.h (NFC) (#97159)

This used to be necessary to fetch the DataLayout, but isn't anymore.

[DomTreeUpdater] Fix use after free in unittests (#97133)

In #96851, the unit test contains use after free, which triggers
sanitizer error.
Fix https://lab.llvm.org/buildbot/#/builders/169/builds/

[DomTreeUpdater] Fix use after free in unittests (#97133)

In #96851, the unit test contains use after free, which triggers
sanitizer error.
Fix https://lab.llvm.org/buildbot/#/builders/169/builds/490

show more ...

Reapply "[CodeGen] Introduce `MachineDomTreeUpdater`" (#96846) (#96851)

This reverts commit 0f8849349ae3d3f2f537ad6ab233a586fb39d375.
Resolve conflict in `MachinePostDominators.h` There is a confli

Reapply "[CodeGen] Introduce `MachineDomTreeUpdater`" (#96846) (#96851)

This reverts commit 0f8849349ae3d3f2f537ad6ab233a586fb39d375.
Resolve conflict in `MachinePostDominators.h` There is a conflict after
merging #96378, resolved in #96852. Both PRs modified
`MachinePostDominators.h` and triggered build failure.

show more ...

[CodeGen] Introduce `MachineDomTreeUpdater` (#95369)

This commit converts most of `DomTreeUpdater` into
`GenericDomTreeUpdater` class template, so IR and MIR can reuse some
codes.
There are some

[CodeGen] Introduce `MachineDomTreeUpdater` (#95369)

This commit converts most of `DomTreeUpdater` into
`GenericDomTreeUpdater` class template, so IR and MIR can reuse some
codes.
There are some differences between interfaces of `BasicBlock` and
`MachineBasicBlock`, so subclasses still need to implement some
functions, like `forceFlushDeletedBB`.

show more ...