Commit Graph

5 Commits

Author SHA1 Message Date
Matt Davis
3e43e69679 [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
Adrian Prantl
076a6683eb Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Andrea Di Biagio
2b25cb95ef [llvm-mca] run clang-format on all files.
This also addresses Simon's review comment in D44839.

llvm-svn: 328428
2018-03-24 16:05:36 +00:00
Andrea Di Biagio
739c509f1d [llvm-mca] Minor refactoring. NFCI
Also, removed a couple of unused methods from class Instruction.

llvm-svn: 328198
2018-03-22 14:14:49 +00:00
Andrea Di Biagio
45f0e5261e [llvm-mca] LLVM Machine Code Analyzer.
llvm-mca is an LLVM based performance analysis tool that can be used to
statically measure the performance of code, and to help triage potential
problems with target scheduling models.

llvm-mca uses information which is already available in LLVM (e.g. scheduling
models) to statically measure the performance of machine code in a specific cpu.
Performance is measured in terms of throughput as well as processor resource
consumption. The tool currently works for processors with an out-of-order
backend, for which there is a scheduling model available in LLVM.

The main goal of this tool is not just to predict the performance of the code
when run on the target, but also help with diagnosing potential performance
issues.

Given an assembly code sequence, llvm-mca estimates the IPC (instructions per
cycle), as well as hardware resources pressure. The analysis and reporting style
were mostly inspired by the IACA tool from Intel.

This patch is related to the RFC on llvm-dev visible at this link:
http://lists.llvm.org/pipermail/llvm-dev/2018-March/121490.html

Differential Revision: https://reviews.llvm.org/D43951

llvm-svn: 326998
2018-03-08 13:05:02 +00:00