Commit Graph

6 Commits

Author SHA1 Message Date
Matt Davis 679083e3d8 [llvm-mca] Make Dispatch a subclass of Stage.
Summary:
The logic of dispatch remains the same, but now DispatchUnit is a Stage (DispatchStage).

This change has the benefit of simplifying the backend runCycle() code.
The same logic applies, but it belongs to different components now.  This is just a start,
eventually we will need to remove the call to the DispatchStage in Scheduler.cpp, but
that will be a separate patch.  This change is mostly a renaming and moving of existing logic.

This change also encouraged me to remove the Subtarget (STI) member from the
Backend class.  That member was used to initialize the other members of Backend
and to eventually call DispatchUnit::dispatch().  Now that we have Stages, we
can eliminate this by instantiating the DispatchStage with everything it needs
at the time of construction (e.g., Subtarget).  That change allows us to call
DispatchStage::execute(IR) as we expect to call execute() for all other stages.

Once we add the Stage list (D46907) we can more cleanly call preExecute() on
all of the stages, DispatchStage, will probably wrap cycleEvent() in that
case.

Made some formatting and minor cleanups to README.txt.  Some of the text
was re-flowed to stay within 80 cols.


Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb, courbet

Subscribers: mgorny, javed.absar, tschuett, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D46983

llvm-svn: 332652
2018-05-17 19:22:29 +00:00
Andrea Di Biagio 904684cf5c [llvm-mca] Remove unused include header files. NFC
Also, run clang-format on RetireControlUnit.cpp.

llvm-svn: 332337
2018-05-15 10:30:39 +00:00
Andrea Di Biagio e2492c860a [llvm-mca] Add file header to RetireControlUnit.cpp.
Strictly speaking, this is not necessary for .cpp files. However, other .cpp
files from this same tool have it. This also matches what we do in other tools.

llvm-svn: 332334
2018-05-15 09:31:32 +00:00
David Blaikie 1ca61f6e1d llvm-mca: Add missing includes
Move the header include in the primary source file to the top to
validate that it doesn't depend on any other inclusions.

llvm-svn: 331897
2018-05-09 17:28:10 +00:00
Matt Davis 21a8d32307 [llvm-mca] Avoid exposing index values in the MCA interfaces.
Summary:
This patch eliminates many places where we originally needed to  pass index
values to represent an instruction.  The index is still used as a key, in various parts of 
MCA.  I'm  not comfortable eliminating the index just yet.    By burying the index in
the instruction, we can avoid exposing that value in many places.

Eventually, we should consider removing the Instructions list in the Backend 
all together,   it's only used to hold and reclaim the memory for the allocated 
Instruction instances.  Instead we could pass around a smart pointer.  But that's
a separate discussion/patch.

Reviewers: andreadb, courbet, RKSimon

Reviewed By: andreadb

Subscribers: javed.absar, tschuett, gbedwell, llvm-commits

Differential Revision: https://reviews.llvm.org/D46367

llvm-svn: 331660
2018-05-07 18:29:15 +00:00
Matt Davis 6aa5dcdcb2 [llvm-mca] Lift the logic of the RetireControlUnit from the Dispatch translation unit into its own translation unit. NFC
The logic remains the same.  Eventually, I see the RCU acting as its own separate stage in the instruction pipeline.

Differential Revision: https://reviews.llvm.org/D46331

llvm-svn: 331316
2018-05-01 23:04:01 +00:00